acterize this cilioablative procedure in an animal model, examine its

TRANSVITREAL ENDOCYCLOPHOTOCOAGULATION

BY Julia A. Haller, MD

"Diseases desperate grownBy desperate appliance are reliev'd,Or not at all."

Hamlet, IV, iii, 9

ABSTRACT

Purpose: Transvitreal endophotocoagulation of the ciliary processes is a lit-tle-used option for eyes with refractory glaucoma. No histopathologicstudies of animals or humans have described its effects. We sought to char-acterize this cilioablative procedure in an animal model, examine itseffects in human eyes histopathologically, and evaluate its clinical safetyand efficacy in a large series of patients with long-term follow-up.

Methods: Animal Model: Rabbit eyes were treated with lensectomy, vit-rectomy, and transvitreal photocoagulation of the ciliary processes. Eyeswere enucleated immediately after surgery and at weekly intervals up to 1month. Light and electron microscopic evaluation of histopathologicchanges was performed. Human Eyes: The pathology laboratory files weresearched for cases with a history of endocyclophotocoagulation prior toenucleation, and three eyes were identified. Histopathologic sections wereretrieved and examined. Clinical Series: A retrospective clinical reviewwas performed of a single surgeon's experience with endolaser to the cil-iary processes, including all cases with adequate data on ocular history,preoperative and postoperative visual acuity, intraocular pressure (IOP),and glaucoma medications, and details of surgery. Only eyes with at least6 months' follow-up were included.

Results: Animnl Model: Histopathologic examination of rabbit eyes treatedwith endocyclophotocoagulation demonstrated acute changes of ciliaryprocess destruction, proteinaceous exudate, stromal edema, nuclearpyknosis, and pigment dispersion. Vascular congestion was seen with somehemorrhage. Later, replacement by fibrous or fibrovascular scar devel-oped with loss of the pigmented and nonpigmented ciliary epithelia,absence of ciliary architectural elements, and pigment rounding andclumping. Human Eyes: Histopathologic examination of enucleated

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human eyes revealed total ablation of the ciliary processes with fibrosisand pigment clumping in areas of treatment. Abrupt transitions betweentreated and untreated regions could be identified. In some areas fibrocel-lular membrane proliferation was found extending over the scars thatreplaced the ciliary processes. Clinical series: Seventy-three patients wereidentified ranging in age from 2 to 85 years (mean, 57.7), with follow-upof 6 to 130 months (mean, 28.6). Mean number of previous operations was3.5; mean number of previous glaucoma operations was 1.3. Preoperativemean IOP was 38 mmHg (range, 19 to 75), postoperative mean IOP was16 mmHg (range, 1 to 50). At 6 months, 58 of 72 eyes (81%) with availableIOP data had IOP greater than 5 mmHg and less than 22. At 12 months48 of 55 (87.3%) were successfully controlled by these criteria, and at lastfollow-up 50 of 73 (68%). Fifty-six of 73 eyes (77%) were considered clin-ically stable at the last foliow-up in terms of visual acuity, anatomic integri-ty, and IOP <23 off all glaucoma medications. Visual acuity was stable orimproved in 53 of 73 eyes (73%). Complications developed in 9 eyes(12%), including IOP <6 mmHg in 6 eyes (8.2%), peripheral choroidaleffusion in 4 (5.5%), fibrinous anterior chamber reaction in 3 (4.1%),phthisis in 2 (2.7%), and choroidal hemorrhage in 1. Thirty-five eyes hadpenetrating keratoplasty performed before or at the same time asendolaser (an average of 2.14 grafts each). Graft rejection occurred in 4eyes (11%), and long-term failure of grafts occurred in 11 of 35 (31%). In31 eyes, additional surgical procedures were performed at the time ofendocyclophotocoagulation.

Conclusions: Endocyclophotocoagulation successfully ablates the ciliaryprocesses, which are replaced with fibrous scar. Surgical results comparefavorably with other methods of glaucoma therapy in complicated eyes interms of IOP control, visual preservation, and complication rate.Endolaser to the ciliary body was especially successful in glaucomatouseyes after keratoplasty, although comeal graft prognosis is limited in thesecases. The technique has particular value in eyes that require other surgi-cal intervention at the time of glaucoma treatment.

INTRODUCTION

To lower intraocular pressure (IOP), there are only two options: increaseoutflow of aqueous fluid from the eye or decrease its inflow. The formerapproach can be applied medically, using drugs such as miotics thatenhance filtering by the trabecular meshwork, or surgically by creatingnew drainage channels in the eye. The surgical options include most

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notably laser trabeculoplasty, filtering surgery, iridectomies, goniotomy,and trabeculotomy. Newer approaches to filtering surgery include the useof pharmacologic agents such as 5-fluorouracil and mitomycin-C to retardhealing and keep patent the filter site, and the use of drainage tubesplaced into the eye as permanent diverting channels for aqueous flow.

Decreasing inflow can also be approached medically, with pharmaco-logic agents such as beta blockers and carbonic anhydrase inhibitors, andsurgically, by destroying the ciliary processes, the tissue that produces theaqueous humor. Ciliodestructive procedures are used in situations whereother forms of therapy, medical and surgical, have failed or have minimalchance of success. The major drawback to cilioablation is that there is alimit to the amount of decrease in aqueous production that can safely beachieved without causing hypotony. It is generally assumed that the mech-anism by which ciliodestructive procedures achieve pressure lowering isby reduction of aqueous humor secretion. Other mechanisms, however,may also play a role, including increased uveoscleral outflow, reducedaqueous production from choroidal detachment, and reduced aqueousproduction from chronic inflammation.'`4

Numerous investigations into new modes of transscleral cilioablationand into alternative surgical procedures for uncontrolled IOP after failureof conventional filtering surgery have been reported over the last decade,but the technique of transvitreal ciliary ablation by endophotocoagulationhas been little studied. No investigations into the histopathologic effects ofthe procedure have been reported, either in animal models or in humans,and only two case series have been published, one a group of 18 eyes witha mean of 6 months' follow-up,5'6 the other a cohort of 42 eyes that includ-ed the previously reported cases.6 We sought to characterize this proce-dure further, first by examining its histopathologic effect in an animalmodel and in human eyes, and second by evaluating its clinical safety andefficacy in a large series of patients with long-term follow-up.

HISTORICAL REVIEW

Cilioablative ProceduresThe concept of intervening at the level of the ciliary body to reduce aque-ous output and consequently to lower the intraocular pressure is far fromnew. Hancock reported his results with cyclotomy in 1861,7 as did Abadie8in 1910. Sclerocyclotomy with thermocautery was described by Fiore in1929,9 and Verhoeff advocated limited cyclectomy.Y' Alternative clinicalinterventions designed to reduce IOP by external cauterization of the peri-corneal and/or ciliary region were performed by Hamburger (silver nitratecauterization), Weekers, Puscariu and Cerkez, Favalaro (following the

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technique of Schoeler), Preziosi, and Curran.7""' According to Bietti,these pioneering steps in cilioablation had "only a restricted number of fol-lowers because of fear that excessive damage to the ciliary body mightoccur.

The advent ofdiathermy brought a new weapon to the field, and in theearly 1930s Weve and Amsler independently performed ciliary bodydiathermy, both superficial and penetrating.7'4

In 1936 Vogt-"'8 developed the ciliodestructive technique that wassubsequently widely adopted in Europe and America. He used electro-diathermy to create ciliary atrophy by making multiple perforations of thesclera over the ciliary body with a thin, short needle (0.2 mm thick and 3mm long). Cyclodiathermy became widely used, in most cases employingpenetrating diathermy electrodes, used either transconjunctivally orbeneath a conjunctival flap. Numerous reports followed this innovation,notably 142 cases reported by Meyer'9 in America and 336 cases describedby Thiel20 in Germany. According to Thiel's data, the treatment served asan "ultima ratio" for difficult cases that were otherwise not operable, witha success rate of about 55%.20 Other investigators reported similar rates ofsuccess, but with serious complications including scleral necrosis, phthisisbulbi, and cyclitis as well as reported cases of endophthalmitis and sympa-thetic ophthalmia.7'23

Variations on penetrating diathermy included the technique describedby Walton and Grant, wherein diathermy was applied so as to "produceexternal filtration from the vitreous cavity through the pars plana at sever-al points," so that the diathermy created a pars plana filtering procedurerather than being used for cyclodestruction. Unfortunately, the procedurewas estimated as being successful only 5% of the time with an equalchance of phthisis.24

Stocker's 1945 report on the response of chronic simple glaucoma tocyclodiathermy puncture detailed 16 successful cases, including refracto-ry cases in black patients, without significant complications.25

A variation of this technique was "cycloanemization" proposed byKettesy,26 in which both long posterior ciliary arteries were obstructed withdiathermy just behind the insertions of the horizontal recti at the level ofthe pars plana. This technique was reported to produce a moderate IOPdecrease with few complications.

Schreck described ciliary damage by reduction of blood supplythrough the process of "cilioanolysis," wherein the long posterior ciliaryarteries were coagulated with anodic electrolysis by passing an electrodesimilar to a dialysis spatula under the sclera in the suprachoroidal spaceand coagulating the arteries gradually.7 Other investigators developed fur-

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ther creative variations on this principle.27Bietti's report of his success with cyclocryotherapy in glaucoma estab-

lished the utility of this technique in 1950.7 Bietti had used solid carbondioxide previously to treat retinal detachments, as had Deutschmann.7"8He found that its effects were milder than those of diathermy, and thusreasoned that it might be as useful, and produce fewer side effects, whenused to treat the ciliary body. Bietti used a thermoelectric couple to mea-sure the temperature of eye structures during the freezing application andperformed experimental treatment on rabbits that documented the local-ized damage caused by the cryotherapy. His 1950 paper reported successin lowering IOP in all 21 patients with complicated glaucoma after treat-ment, 12 of whom had good final IOP control. Two patients developedlong-term hypotony.

Cyclocryotherapy was widely popularized by de Roetth29 in 1968, withnumerous publications following.`?4" Bellows and Grant3 discussed theircyclocryotherapy series in 1978 and found favorable results in eyes withaphakic open-angle glaucoma. Their patients with penetrating keratoplas-ty were the subset with the most successful IOP control, although with ahigh rate of corneal rejection. Similarly, West and associates3' and Binderand colleagues346 reported good results with cyclocryotherapy after pene-trating keratoplasty in terms ofpressure reduction, with the common priceof graft failure. Series reporting success rates with cyclocryotherapy inneovascular glaucoma described mixed results. Feibel and Bigger-'l (1972)found that cyclocryotherapy was quite successful in their patients. In con-tradistinction, Faulborn and Birnbaum,4" Krupin and coworkers,4' Shihaband associates,44 and Boniuk34 found that visual results were almost uni-formly poor in this serious disease, although pressure control was goodwith relief of pain. In 1986 Brindley and Shields37 reviewed their consecu-tive series of 114 eyes treated with cyclocryotherapy for intractable glau-coma. Intraocular pressure reduction sufficient to avoid further surgicalintervention was achieved in two thirds of the cases. However, postopera-tive vision was worse than preoperative vision in 60%, and 12% of eyesdeveloped phthisis. As in other series, the treatment was least successfulin eyes with neovascular glaucoma and most successful in aphakic eyes.These investigators made the additional original observation that youngpatients required the most extensive cryotherapy to achieve adequate IOPcontrol. They therefore advocated that young patients (under 45 years)have initial treatment of2700 of ciliary body circumference rather than thestandard initial treatment of 1800. About one fourth of cases requiredadditional cryoprocedures to achieve a satisfactory pressure level.

In 1961 Weekers and coworkers45 described cyclodestruction with

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light energy, employing transscleral xenon arc photocoagulation. Theinvestigators studied the effect of transscleral xenon arc photocoagulationon the ciliary body of rabbits. Days after treatment, thrombosis of the cil-iary processes was seen with disruption or loss of the epithelial cell layers.Two months later, the principal damage was in the ciliary epithelium withpigment clumping and vacuolization. Subsequent investigators employedruby, neodymium, argon, krypton, and neodymium-YAG (Nd:YAG) lasersto produce destruction of the ciliary processes via a transscleralapproach.3,323346-80 Beckman and colleagues46,4776 investigated the lasertransscleral approach to cyclodestruction with both ruby and neodymiumlasers and described their experience over a decade with 241 eyes treatedby transscleral ruby cyclophotocoagulation. The overall rate ofIOP controlwith the ruby laser was 86% in eyes with aphakic glaucoma and 53% ineyes with neovascular glaucoma. Chronic hypotony occurred in 41 eyes inthis series and phthisis in 17 cases. Most eyes retained preoperative visualacuity levels.

Beckman and Waeltermann" studied the transscleral ruby laser'shistopathologic effect on the ciliary body of rabbits. They noted acutechanges ofhyperemia and hemorrhage with edema of the ciliary body withpatchy epithelial degeneration and necrosis. This was followed morechronically by fibrosis and atrophy of the ciliary processes and body.Collateral damage was seen in the peripheral retina with inflammation andsubsequent atrophy and degeneration of the posterior lens capsule andfibers with focal hyperplasia of lens epithelium adjacent to treated ciliaryprocesses.

Peyman and coworkers4l reported a series of transscleral laser proce-dures performed on rabbit eyes with argon and krypton laser and on mon-keys with argon laser. No identifiable histopathologic damage was seen inthe ciliary body of the rabbit eyes. The monkey eyes showed vasodilation,exudates, and coagulative necrosis of the ciliary body acutely. One monthafter treatment, migration and proliferation of the pigment epithelium wasseen with clumping.

Kivela and coworkers49 performed histopathologic and immunohisto-chemical studies on an autopsy eye treated 10 months prior to death withkrpton laser cyclophotocoagulation. The ciliary processes were destroyed,with intact sclera and zonules. Little chronic inflammation and no signs ofsympathetic ophthalmia were present. The ciliary muscle was found to beatrophied, suggesting that loss of accommodative capacity might compli-cate this procedure in young patients.

Numerous reports on the use of the transscleral Nd:YAG laser for cil-ioablation have been published.3'32334681 Early results appeared promising,

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with few complications and success rates of 49% to 71%. Hampton andcoworkers69 reported 100 eyes in a 1990 pilot study. With a mean follow-up of 11 months (range 1 to 21 months), IOP between 7 and 21 mm Hgwas achieved with one treatment in 51%. With additional treatments, suc-cess rates rose to 65%. However, 45% developed visual loss, and othercomplications included transient IOP rise in 23 eyes, severe pain in 12,and severe inflammation in 29.

Both Trope and Murphy'1 and later Hampton and colleagues69 went onto report a significant incidence of hypotony, phthisis, and visual loss aftertransscleral Nd:YAG in eyes followed longer than 6 months.' In the seriesfrom Trope and Murphy,68 10.7% of eyes became phthisical and 30% ofeyes lost vision postoperatively despite good IOP control.

In 1991 Balazsi65 reported a series from Montreal in which he used alower level of energy when performing the cyclophotocoagulation thanmost other investigators. His 35 eyes achieved "successful control" of IOP(defined as 5 to 21 mmHg in eyes with count fingers or better acuity, 5 to25 in eyes with hand motions to light perception vision, and control of painin eyes with no light perception), in 71% to 75% of cases. Vision decreasedin 5 eyes. Significant postoperative pain and inflammation developed in alleyes treated. Other complications included hypopypon, vitreous hemor-rhage, IOP spikes, graft failure, severe chemosis, and phthisis bulbi.

In 1992 Schuman and coworkers51 detailed their results in a series of116 eyes followed for a minimum of 1 year after contact transscleralNd:YAG cyclophotocoagulation. Postoperative IOP levels of 3 to 25mmHg were achieved in 72% of eyes, 3 to 22 mmHg in 65%, and 3 to 19mmHg in 56%. Retreatment was required in 27%, and IOP less than 3mmHg developed in 9 eyes. Nineteen eyes progressed to no light percep-tion vision and 17 of 36 (47%) of eyes with vision 20/200 or better lost 2 ormore lines of Snellen acuity.

Other investigators described additional complications of Nd:YAGcyclophotocoagulation including inadvertent sclerostomy, malignant glau-coma, choroidal detachment, flat anterior chamber and hypotony, andsympathetic ophthalmia.71-7478 A small number of patients were found todevelop immediate postoperative pressure spikes, which imperiled opticnerve heads with significant pre-existing compromise.'

The subset of eyes treated with Nd:YAG transscleral photocoagulationfor uncontrolled IOP postkeratoplasty was studied by Threlkeld andShields54 as well as by Cohen and coworkers.55 The latter series of 28 eyeswas reported in 1989, with follow-up of 6 to 28 months (median 18months). Multiple treatments were necessary in 46% of eyes. Intraocularpressure fell to 22 mmHg or less in 20 (74%) at 6 months and 16 of 24

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(67%) at 1 year. Five eyes failed all cyclophotocoagulation treatments andunderwent cyclocryotherapy or aqueous shunting procedures. Six (43%) ofthe grafts which were clear before surgery failed postoperatively. The 1995series reported by Threlkeld and Shields included 39 patients with follow-up from 3 to 63 months (mean 27 months). At final follow-up 31 patients(77%) maintained an IOP between 7 and 21 mmHg. Twenty two patients(56%) had a deterioration in visual acuity, and 44% of the preoperativelyclear grafts failed. Other complications included uveitis, sustainedhypotony in 12%, loss of light perception in 9%, severe pain,hyphema/hypopyon, and phthisis.

In 1964 Purnell82 and coworkers proposed destroying the ciliary bodywith their new ultrasonic device as a means of treating high IOP. The useof focused ultrasound for cilioablation was further investigated in the late1970s and 1980s.83-m After several small studies showed promising results,a multicenter clinical trial was initiated, with results published in 1991.86This series included 880 eyes treated at 20 centers in the United Statesand was limited to patients with glaucoma refractory to conventional med-ical and surgical therapy. The single-treatment success rate (IOP between6 and 22 mmHg) was 48.7% at 6 months after treatment. The 1-year sin-gle-treatment success rate was 38.1%. Some of the failures were thenretreated, and of the 559 eyes so treated, 83.9% had IOPs in the accept-able range at 6 months, 79.3% at 1 year. Treatment was most effective ineyes with open-angle glaucoma and least successful in eyes with congeni-tal glaucoma and neovascular glaucoma. The best rates overall werereported by study centers treating the most patients, suggesting that expe-rience impacted positively on results. The highest initial success rate wasat Cornell (90%), but was accompanied by the highest study center rate ofphthisis. Ten of the 12 eyes in the overall study with phthisis were treatedat Cornell. Decrease in visual acuity developed in 173 of 863 of patients(20%). Complications unique to this form of treatment occurred in someeyes: 106 eyes developed corneoscleral lesions and 16 had eyelid burns.Mild iritis developed in 210 eyes, moderate iritis in 70, and severe iritis in4 (total with iritis 284 or 33%). Other complications present in small num-bers were corneal edema and keratopathy (3.4%), phthisis (1.4%), cataract(1%), and conjunctivitis, keratitis, scleral thinning, staphyloma, scleral per-foration, flat anterior chamber, hyphema, pupillary block, ciliary bodyhemorrhage, iris rubeosis, vitreous hemorrhage, cystoid macular edema,macular membrane, retinal detachment, and choroidal effusion or detach-ment (all < 1%).7,86 Because of the technical requirements of focusedultrasound, this technique has not been widely adopted by glaucoma sur-geons to date, although a large number of patients have been treated at

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referral centers in the United States and Europe.The diode semiconductor laser has also been used for transscleral

cyclophotocoagulation. In 1992 Hennis and Stewart87 reported a series of14 patients with refractory glaucoma who were judged to be poor candi-dates for filtering surgery. At 6 months, IOP between 7 and 21 wasachieved in 8. Complications included mild uveitis and conjunctival burnsin all patients. No patient developed hypotony or phthisis.

In 1993 Hawkins and StewartTm reported their results in 27 patientstreated with transscleral diode cyclophotocoagulation and followed for 1year. Eight patients (27%) required other procedures to control IOP, and11 of 27 (41%) maintained IOPs of 21 mmHg or below or achieved painrelief (6, 22%). Seven (26%) sustained visual loss of two lines or more.

A number of investigators have described the histologic effects oftransscleral diode laser on the ciliary body and retina of monkeys and rab-bits. Mild scleral damage occasionally occurs, with marked destruction ofthe ciliary body and production of a chorioretinal scar.53

Lee and PomerantzeffP9 reported transpupillary laser treatment of theciliary processes in normal rabbits and rabbits with hereditary buphthal-mos in 1971. Histopathologic evaluation of treated eyes showed destruc-tion of the pigmented and nonpigmented ciliary epithelium with inflam-matory infiltration acutely. One year later, eyes showed atrophy of the cap-illaries, pigment clumping, and damage to the epithelial cells, greater tothe nonpigmented than pigmented cells. Bartl and coworkers90 furthercharacterized the histopathology of this therapy by examining human eyestreated prior to enucleation with transpupillary argon laser.

In 1979 Lee9' reported the clinical efficacy of this technique in a smallpersonal series. His 14 patients included 12 with previously failed glauco-ma surgery. Using a gonioscopic lens to deliver the argon laser, he treatedbetween 8 and 27 processes, totaling one tenth to two fifths of the entirecircumference of the corona ciliaris. Treatment parameters were 1,000mW, 0.1 to 0.2 seconds, and 50 to 100-pm spot size, with an endpoint of abrown burn, often with a gas bubble. Lee pointed out that whitening alonemight not indicate damage to the process but only whitening of adjacentvitreous or residual lens material. Ten eyes (71%) had successful loweringof IOP after this procedure. Tonography demonstrated that the outflowfacility in the treated eyes was not significantly affected. The impact oftreatment appeared to be solely on aqueous humor production.Complications included transient corneal epitheliopathy, mild iridocyclitis,and hemorrhage in one eye. Treatment effects lasted 3 months to 3 yearsor more, with re-treatment needed in 7 eyes and 4 treatments needed in1 eye. Lee ascribed the gradual postoperative increase in IOP that he

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found in part to regeneration of the secretory mechanisms of the ciliaryprocesses and in part to "worsening of the glaucoma." He characterizedtranspupillary treatment of the ciliary processes as "a more refined proce-dure" than transscleral argon laser or cyclocryotherapy, with less variableresults and less severe posttreatment complications. Other reports of theclinical value of this technique in small case series found it to be occa-sionally, but not uniformly, effective.294 Bernard and colleagues92 pointedout that its use was mainly limited to eyes with large iridectomies, neovas-cular glaucoma with iris retraction, aniridia (natural or traumatic), certaineyes with subluxed lenses and vitreous retracting the iris, and occasionaleyes widely dilatable pharmacologically. The limiting factor was the num-ber of ciliary processes that could be visualized and treated.

Shields4O reported his results with transpupillary argon photocoagula-tion of the ciliary processes in 1986. In the 16 eyes included in this series,glaucoma mechanisms included aphakia, neovascular glaucoma, trauma,and open-angle glaucoma with multiple failed filtering procedures. Thenumber of gonioscopically visible and treated processes ranged from 7 toall 3600 of the ciliary body with an average of 26 processes. Of the 16 eyestreated, adequate IOP control was achieved in only 4. Shields speculatedthat failure of this technique might be attributed to the low number of vis-ible and thus treatable ciliary processes. Against this theory was the factthat in the successfully treated group in his series, the number of treatedprocesses ranged from 8 to all processes, essentially the same as in theunsuccessful group. Another possible contributor to the high failure ratewas inadequate burn power. The white burn typically achieved may nothave produced sufficient ciliary damage. Shields found it necessary toincrease laser energy to achieve a concave brown burn, often with pigmentdispersion and/or production of a gas bubble. Finally, he postulated thatinadequate extent of treatment even of the apparently well-visualized andlasered ciliary processes may also have contributed to inadequate pressureresponse. He found that in a primate model, the gonioscopically visualizedciliary process could often only be seen to the tip of its anterior ridge, evenwith scleral indentation. Histologic evaluation of the treated tissuerevealed retention of normal morphology in the posterior portion of theprocesses when examined 1 to 8 months after surgery.4095

Charles96 described a single case of transvitreal photocoagulation ofthe ciliary processes in a 1981 report on 169 eyes that received intraoper-ative laser endophotocoagulation during vitreoretinal surgery. A xenon arccoagulator was used with a modified fiberoptic tip. One patient with neo-vascular glaucoma and recurrent vitreous hemorrhage after vitrectomyunderwent vitreous washout with panretinal endophotocoagulation and

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endophotocoagulation to about one half of the ciliary processes. The IOPremained in a normal range until the patient's death 7 months postopera-tively.

Shields and coworkers4097 described the histologic effects of endo-scopic argon photocoagulation on primate eyes. Pars plana lensectomy andvitrectomy were performed, and an endoscopic photocoagulator was intro-duced through the pars plana incision. The investigators found that treat-ment levels as high as 700 to 1,000 mW were necessary to achieve thedesired tissue effect. This level of treatment was often accompanied byslow oozing of blood from the treated process that stopped spontaneouslyand did not obscure visualization of adjacent processes. Problems wereincurred when incomplete removal of lens cortex partially obscured visu-alization of the ciliary processes in 4 eyes. A moderate choroidal detach-ment developed in 1 eye but did not interfere with laser treatment.Histopathologic evaluation revealed varying levels of acute tissue damagewith cellular disruption, hemorrhage, and vacuolization. Eyes examined 1to 8 months after treatment revealed a flattening of the ciliary processeswith overlying fibrosis or a partial disruption of the epithelial layers. Someprocesses were replaced by a flattened fibrotic mass. Blood vessels werescant or absent in the sections studied. Damage was very focal, and con-tiguous structures were preserved. Adjacent ciliary processes and theunderlying ciliary muscle were spared.

In 1986 Patel and associates5 reported a series of 18 eyes with severeglaucoma followed for an average of 6 months after transvitreal endocy-clophotocoagulation. In 1988 Zarbin and coworkers6 expanded this pre-liminary series to 42 patients, including the previously described 18 eyes.The earlier report found reduction of IOP to 20 mmHg or less in 14 of 18eyes with severe glaucoma refractory to maximum-tolerated medical ther-apy and glaucoma filtering surgery. Nine of 14 successfully treated eyesrequired postoperative medical therapy. Systemic carbonic anhydraseinhibitors were discontinued in 13 of 17 patients. Surgical techniqueemphasized treatment of the entire anteroposterior length of the ciliaryprocesses, with whitening and shrinkage. The ciliary body was treatedthroughout a circumference of 2400 in most cases, using power settings of500 to 700 mW and durations of 0.5 to 1.0 seconds.

The second clinical report tabulated results on 42 glaucomatous eyesin the following categories: secondary angle-closure glaucoma (14 eyes, 11with prior penetrating keratoplasty and 3 with numerous anterior segmentsurgical procedures), neovascular glaucoma (8 eyes), angle damage fromblunt trauma (6 eyes), open-angle glaucoma (5 eyes), aniridia (2 eyes),congenital glaucoma (2 eyes), epithelial downgrowth (2 eyes), and uveitis

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(3 eyes). Multiple previous surgical procedures had failed, including argonlaser trabeculoplasty (2 eyes), goniotomy (3 eyes), iridencleisis (2 eyes),trabeculectomy (20 eyes), cyclocryotherapy (10 eyes), focused ultrasound(1 eye), and cyclodialysis (1 eye), with a mean of 1.5 previous glaucomaprocedures. Follow-up ranged from 6 months to 36 months (mean, 13months). Vision improved by greater than two lines in 9 eyes (21%), didnot change in 20 (48%), and worsened by more than two lines in 12 (29%).The postoperative IOP ranged from 1 to 44 mmHg (mean, 17 mmHg).The absolute change in IOP ranged from +4 mmHg to -59 mmHg (mean,20 mmHg decrease). The procedure was least successful in eyes with con-genital and uveitic glaucoma. Twenty-three of 32 patients (72%) takingsystemic carbonic anhydrase inhibitors preoperatively were able to dis-continue them. Complications occurred in 12 (28%) of the eyes studied.Intraocular pressure less than 10 mmHg occurred in 4 eyes. No phthisisbulbi developed in any eye. Two eyes had a retinal dialysis, and 2 eyes hadpostoperative vitreous hemorrhage, 1 requiring vitreous lavage.Ciliochoroidal detachment associated with hypotony developed in 2patients, 1 requiring surgical drainage. One eye developed a retinaldetachment with proliferative vitreoretinopathy.

Uram98 described the technique of diode laser cyclophotocoagulationthrough an endoscopic system in 1992, reporting a series of 10 patientswith neovascular glaucoma. Patients underwent pars plana lensectomy andvitrectomy (unless already aphakic) and then had an ophthalmic lasermicroendoscope introduced through a pars plana incision. The instrumentwas 20-gauge, with the triple functions of illumination, laser energy deliv-ery, and endoscopic viewing. Diode laser energy was delivered, with pow-ers of 200 to 300 mW, applied for 1 to 2 seconds. The eyes were treatedfor 900 to 1800 of ciliary body circumference. Follow-up ranged from 6 to11 months. Average preoperative IOP of 43.6 mmHg decreased to anaverage postoperative level of 15.3 mmHg. Nine of the 10 eyes had a pres-sure less than 21 mmHg. In 6 of 9 cases, carbonic anhydrase inhibitorscould be stopped. Two eyes at last follow-up had hypotony (IOP, <10mmHg), but no eyes developed phthisis. The report emphasized theadvantage of an endoscopic approach to transvitreal laser cycloablation: itavoids the necessity of a clear cornea or widely dilated pupil. Tissue effectswere achieved at substantially lower power levels than with the argon laser,Uram postulated, because of the 810-nm wavelength of the diode laser.

Alternatives to Cilioablative Procedures in Eyes with UncontrolledGlaucomaFiltering procedures are successful in lowering IOP to less than 21 mmHg

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in 75% to 95% of eyes when performed as a primary surgical procedurefor uncomplicated open-angle glaucoma or chronic closed-angle glauco-ma.'," The adjunctive use of pharmacologic agents such as 5-fluorouracilor mitomycin-C to retard fibrosis improves the success rate of filtration ineyes with complicated secondary glaucomas (eg, uveitic or neovascular)and in eyes that have undergone cataract removal or failed previous stan-dard glaucoma surgery.'00'02 Surgical failures still occur despite antimetabo-lite therapy owing to scarring at the sclerostomy site, the conjunctiva,Tenon's capsule, and/or scleral tissues. For this reason, tube implants thatshunt aqueous from the eye to the orbit have been developed and put intoclinical practice.'01"1l3l4

The first seton was described in 1912 by Zorab,"'5 who termed his pro-cedure an "aqueoplasty," implanting a strip of silk or linen across the lim-bal wound to create a fistulous tract. Later, investigators were creative intheir search for more efficacious setons. Materials as varied as horse hair,gold foil, silk thread, tantalum wire, glass, platinum, polymethylmethacry-late, polyethylene, gelatin, autologous cartilage, autologous lacrimalcanaliculus, and gel film were inserted into the anterior chamber beneatha scleral or conjunctival flap.27'105-114 The bae noire of these procedures waspostoperative fibrosis, with a high rate of fistula closure, despite the pres-ence of the foreign body.

Later, investigators developed tubes to shunt aqueous from the ante-rior chamber to the subconjuctival space, but the procedures wereplagued by the tendency of the conjunctiva to seal down to the scleraaround the distal end of the shunt, preventing aqueous diffusion.01"15"16

Tubes to shunt aqueous from the anterior chamber to an artificiallycreated subconjuctival reservoir were pioneered by Molteno and coinves-tigators.117-123 A scleral plate was connected to the seton, so that aqueoushumor was shunted from the anterior chamber 10 to 12 mm posteriorly toa reservoir formed by fibrous encapsulation around the implanted plate.The IOP was controlled by the passive, pressure-dependent flow of fluidacross the capsular wall.04 The magnitude of pressure reduction depend-ed on the capsular wall resistance to aqueous humor flow: thus the thinnerthe capsule, the better the flow, and the lower the IOP. The total surfacearea of the capsule also appeared to be important: the larger the surfacearea of the explant, the more extensive the area of encapsulation aroundit, the faster the flow, and the lower the IOP. Studies evaluating thedynamics of anterior chamber shunt devices have shown that little resis-tance is offered by the tube and that there is relatively free flow back andforth from the interior of the eye to the encapsulated reservoir through thetube at equilibrium. Thus to achieve the lowest postoperative IOP, the size

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and permeability of the capsular wall should be maximized. The mecha-nism of aqueous permeation through the capsular cavity is still unclear. Inthe case of the Schocket encircling implant, horseradish peroxidase inject-ed into the anterior chamber was found not only in the space between theencircling implant and Tenon's capsule but also inside Tenon's capsule andorbital vessels.'104

The size of the fibrous capsule is determined at least in part by the sizeof the reservoir explant to which the tube is shunted. A study was per-formed in which 132 patients with intraocular aphakic or pseudophakicglaucoma were randomly assigned to single or double Molteno plates.'24After 1 year and 2 years, the success rates (defined as IOP .6 and < 21mmHg without additional glaucoma surgery or devastating complication)were 55% and 46% with the single plate and 86% and 71% with the dou-ble plate. Double plates were, however, associated with greater risk ofchoroidal effusion and/or hemorrhage, corneal decompensation, flat ante-rior chamber, and phthisis bulbi.

The Molteno tube was designed to connect without a valve to a singleor double plate sutured to the posterior sclera. Schocket and coworkersused a scleral buckling element to produce a posterior reservoir for aque-ous drainage, originally encircling the eye and then later modifying thebuckle to varying circumferential dimensions (180 degrees, 90degrees).104"'8"25The Baerveldt drainage device was similarly nonvalvedand connected to a scleral plate available in several sizes (200, 350, and500 mm2) 126,127

Complications with too-rapid egress of aqueous occurred with shunt-ing systems, including hypotony and associated choroidal effusions,choroidal hemorrhages, and flat anterior chambers in the early postopera-tive period. In response, the design on the Krupin and Joseph tubes incor-porated a valve to reduce early outflow to more physiologic levels.128 129Later modifications of the implantation procedures for the nonvalved sys-tems included tying a releasable suture around the tube to slow postoper-ative flow initially, thus blurring the difference between the valveless andvalved systems 130,31

The different implants currently in use vary also according to numberof quadrants of dissection required for installation, material, and shapeand dimensions of the scleral explant. The Krupin system is placed within1 ocular quadrant. The double-plate Molteno requires 2 quadrants, theSchocket 1 to 4 quadrants, and the Baervelt 1 quadrant. With the excep-tion of the Molteno explant, which is made of polypropylene (formerlymade of an acrylic substance), all the others are made of silicone material,which may be less reactive and may inhibit the attachment and prolifera-

602


tion of fibroblasts, thus interfering with connective tissue ingrowth.Ultimately, the important issue is which characteristics of the explant

provide the ideal aqueous reservoir. This is then factored in with clinicalconsiderations such as ease of insertion, success rate, and complicationrate to determine a glaucoma surgeon's preferred drainage system.

Results with Molteno implants describe adequate pressure control in47% to 100% of cases." 3 '32'5' In black patients, Freedman and Rubinl'4found that 72% maintained pressures lower than 21 mmHg with a meanfollow-up of 30 months. In infantile glaucoma, Munoz and coworkers"l4reported a 68% rate of success (IOP, <21 mmHg) with a mean of 18months' follow-up. Fourteen of 53 eyes (26%) required further glaucomasurgery. Six (11 %) of the late failures were attributed to bleb encapsula-tion, a particularly difficult problem in young patients. Hill and cowork-ers'37 also studied the success of Molteno implants in young patients andfound that IOP between 5 and 22 mmHg was obtained in 62% of theirpatients followed between 6 and 59 months. Only 22 eyes (34%) of the 65in this series were controlled after one procedure, however, and 54 (83%)underwent further surgery of some sort.

In neovascular glaucoma cases, Molteno and associates"17 reported in1977 that 6 of 12 eyes had postoperative pressures between 12 and 20mmHg and an additional 5 eyes had IOPs between 20 and 30 mmHg withfollow-up of 6 to 38 months. Mermoud and associates'4' reported a 62%success rate with neovascular glaucoma at 1 year, 53% at 2 years, and 43%at 3 years. A full 48% lost light perception, and 18% developed phthisis.Age older than 55, a diagnosis of central retinal vein occlusion, and visualacuity worse than 6/60 were risk factors for poor outcome.

Airaksinen and coworkers'32 reported that 73% of their series of com-plicated eyes with a variety of glaucoma etiologies had successful pressurecontrol after Molteno implantation with an average of 18.3 months follow-up. Melamed and coworkers"4 reported that 78% of patients with Moltenodevices had pressure control at 16 months' average follow-up. Mincklerand colleagues'44 described 79 patients who underwent Molteno place-ment, with successful lowering of IOP .21 mmHg in 63% of aphakic andpseudophakic patients older than 12 years with nonneovascular glaucoma,70% of older patients with phakic eyes who had failed filtering surgery,47% of eyes with neovascular glaucoma, and 54% of eyes with juvenileglaucoma. Hill and associates'37 reported a 79% success rate in patientswith uveitis-associated glaucoma after Molteno implantation.

After penetrating keratoplasty, McDonnell and associates'39 reportedthat 12 of 17 eyes (71%) achieved IOP of less than 21 mmHg after 1Molteno operation and 14 of 17 (82%) after 2 operations. Corneal rejec-

603

Haller

tion occurred in 7 of 17 eyes (41%), and 2 of these episodes were reversedwith use of corticosteroids. Three of 5 graft failures were regrafted, and 2remained clear, so that ultimately 13 of 17 eyes had clear grafts and con-trolled IOP. Kirkness,"'5 Sherwood and colleagues,'48 and Beebe andcoworkers"54 also reviewed their experiences with Molteno or Schocketprocedures after penetrating keratoplasty with similar results, includingrelatively high levels of both IOP control and graft failure. Beebe andcoworkers"54 found 86% of 35 eyes were ultimately successful from a glau-coma standpoint, and 25 of 35 grafts were eventually clear, although 10required regrafting. Sherwood and colleagues'48 found that 96% of theirpatients had IOP of less than 18 mm Hg at last follow-up and 70% hadpreserved visual acuity at the preoperative level. Graft failure occurred in42%, although 6 of 8 eyes were successfully regrafted."48 One postulatedmechanism for the high comeal transplant rejection rate after implanta-tion of a drainage device is that the implant serves as a foreign body orconduit for inflammatory cells into the anterior chamber."l5

In 1982 Schocket and associates'03 described 18 of 19 patients withneovascular glaucoma who were treated with a tube shunt to an encirclingband with IOP <20 mm Hg after 5 to 26 months of follow-up.

Hitchings and associates's5 published their results with a modifiedform of the Schocket tube and found that 70% of patients had a postoper-ative IOP of <21 mmHg at 6 to 24 months. Significantly, of the 35 patientswith greater than 12 months' follow-up, only 16 did not require reopera-tion. Omi and coworkers"6 reported 55 eyes in 1991 with a variety of glau-coma diagnoses treated with the Schocket procedure. In 45%, the shuntprocedure was the first glaucoma operation performed. Final IOP of <21mmHg was achieved in 50 of 55 (90.9%). Complications occurred in23.6%.

These 2 shunting devices were compared in a randomized prospectivestudy by Smith and colleagues in 1992,150 with 21 eyes in the Schocketgroup and 19 in the Molteno group. Postoperative lOPs averaged 14.4 inthe Molteno group and 15.1 in the Schocket group. Complications requir-ing further surgery were encountered in 47% of the Molteno eyes and57% of the Schocket eyes.

Fellenbaum and coworkersl' reported their series of Krupin shuntedeyes in 1994. At 6 months, 84% had IOP between 6 and 21 mmHg, and at1 year, 66%. In 1994 the Krupin Study Group9 reported that 80% of 50eyes with varied glaucoma diagnoses achieved IOP of less than 19 mmHgafter Krupin implants with more than 2 years' follow-up. Krupin andcoworkers'28 reported their success with the Krupin valved shunt in thesubset of patients with neovascular glaucoma: 53 of 79 eyes had final IOP

604


of < 24 mmHg. Ten of these 53 required bleb revision. In a later series,Krupin and associates'57 reported that they achieved IOP of <21 mmHgwith the Krupin valve in 77% of patients with neovascular glaucoma and82% of patients with a variety of nonneovascular disease.

The initial 13 eyes followed in the preliminary studies of the Baerveldtshunt and reported by Lloyd and associates in 1993 had a 62% success ratedefined as IOP between 6 and 21 mmHg. A later series reported by Lloydand colleagues'26 in 1994 compared the medium (350 mm2) and larger (500mm2) explants in 73 patients with nonneovascular glaucoma. The investi-gators found 93% of eyes in the medium group and 88% in the large groupwith postoperative IOPs between 6 and 21 mmHg.

Hodkin and coworkers"25 reported a 72% success rate with theBaerveldt shunt, reducing IOP to less than 21 mmHg in 36 of 50 eyes witha variety of glaucoma diagnoses. The results with Baerveldt shunts in eyeswith neovascular glaucoma were described in a 1995 report by Siegner andcoworkers."8 Of the 103 eyes reviewed, 72.6% had IOP between 5 and 22mmHg at 6 months, and 60.3% at 24 months. Complications occurred in71.8%, although in 45% these were transient and self-limited.

A 1995 study comparing the Baerveldt shunt to the Molteno doubleplate found that 16 of 18 eyes with the former and 17 of 19 with the latterwere successfully controlled with IOPs between 7 and 19 mmHg."4" Only8 of the 34 eyes had undergone previous trabeculectomy.

The intraoperative and postoperative complications associated withaqueous shunting procedures are similar with all types of devices current-ly in use.'27'9157 Complications have been reported in up to 100% of casesstudied.140'141 Intraoperatively, perforation and exposure of uveal tissue mayoccur as the implant is fixated to the sclera or as the scleral flap is dissect-ed. Use of banked sclera to cover the tube has decreased this problem.This is particularly true in eyes that have been operated on multiple timeswhere the tissues may be thinned and friable. Erosion of the implantsthrough sclera or conjunctiva is reported in 3% to 7% of cases.' 41""4

Insertion of the tube into the eye may be accompanied by complica-tions. Too posterior an entry into the anterior chamber may result in cil-iary body bleeding and vitreous loss. Kinking of the tube may result fromplacement out of the parallel with respect to the iris plane, with later tubecontact with the cornea, iris, or lens.

The most frequent serious postoperative complications are prolongedhypotony, flattening of the anterior chamber, and tube-corneal contact.Flat anterior chamber and hypotony were present in the early postopera-tive period in 23% to 100% of single-plate one-stage Molteno implantswhen first introduced.140-142 These complications were subsequently

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Haller

reduced by modifications such as changing drainage device design toinclude a valve, staging the operation, temporarily ligating the tube post-operatively, and using a scleral patch graft, but still occurred in 6% to 20%of cases.'41'142

Contact between the cornea's endothelial surface and the anteriorchamber tube is reported in 3% to 8% of cases.'40"41 This is usually not aserious problem for the short term, as any opacity created is off the visualaxis at least initially. However, long-term progressive endothelial insuffi-ciency may result in corneal decompensation, edema, and opacity. Cornealdecompensation is reported in 11% to 18% of cases and is particularlyproblematic in patients who have undergone penetrating keratoplasty. 31"141,148,153,154

Prolonged hypotony may eventuate in tube migration further into theanterior chamber, sometimes crossing into the pupillary space. Iris tissuemay occlude the tube and cause early failure of the procedure. Laser treat-ment (Nd:YAG or argon) may help to restore tube patency and clear irisfrom the tube mouth. Contact between the tube and lens may causecataract formation, while tube-IOL contact can dislocate the lensimplant.'40"4' Contact between the tube and vitreous gel may block egressof aqueous. Other sources of tube obstruction include fibrin, blood clot,and synechiae. Overall, tube blockage is a problem in about 6% to 12% ofcases. Postoperative hyphema is reported as occurring in 14% to 21% ofeyes but usually resolves within a few days. Hyphema may also occur,especially in patients with neovascular glaucoma, as rubeotic iris vesselsmay bleed extensively.'41

Choroidal effusions, whether limited and peripheral or extensive,occur in 16% to 34% of eyes undergoing aqueous shunting procedures,and choroidal hemorrhage occurs in 6% to 8%. 2799-06125l52-l57l59 Pupillaryblock glaucoma, malignant glaucoma, and endophthalmitis are rare,reported in less than 5% of cases. The risk of retinal detachment has beenestimated at 5% after aqueous shunting procedure, but these detachmentstend to be complicated, with proliferative vitreoretinopathy reported aspresent in 41%; in one series,'5' 44% of eyes with such detachments wenton to phthisis or enucleation. Vitreous hemorrhage occurs in 2% to 5% ofcases, more often in some series with neovascular glaucoma.141 Phthisisbulbi results in 2% to 6% of cases.Y4'

The Baerveldt valve was reported in 1993 by Smith159 to be associatedwith significant extraocular motility restriction and heterotropia. In thisearly series, 77% of patients were left with a heterotropia and 65% werediplopic. Only an estimated 6% of patients with Molteno valves had expe-rienced similar problems. After subsequent modifications to the Baerveldt

606


valve and its insertion technique, including fenestrating the reservoir tominimize the fibrosis restricting muscle movement, reported extraocularmotility problems decreased to about 6%, approximately the same rate aswith other available explants.149'158

Excessive conjunctival scarring is the most common cause of late fail-ure of aqueous shunting procedures, as fibrosis of the encapsulated blebproduces greater and greater resistance to aqueous and the flow of fluidposteriorly ceases. Revision is required in 6% to 7% of cases. 114'

MATERIALS AND METHODS

ANIMAL MODEL

Histopathologic studies of eyes after laser treatment to the ciliary process-es include a rabbit and primate series treated with transpupillary argonlaser, human eyes treated with transpupillary argon laser prior to enucle-ation, and a series ofprimate eyes treated endoscopically with laser.40'9568997No investigators have reported a series of eyes treated with pars plana vit-rectomy and transvitreal cyclophotocoagulation using standard operatingmicroscope visualization.

Accordingly, a protocol was developed for evaluating the histopatho-logic effects of endocyclophotocoagulation in a rabbit model. The propos-al was approved by the institutional committee evaluating all animalresearch protocols, and conformed to the standards set by the Associationfor Research in Vision and Ophthalmology.

Ten pigmented rabbits were sedated and anesthetized with intramus-cular ketamine and xylazine. One eye was proptosed, prepped withantibacterial solution, and draped. Conjunctival pocket incisions weremade nasally and temporally. Pars plana sclerotomies were performednasally and temporally, and an irrigating 23-gauge butterfly needle wasintroduced through the nasal site and a fragmatome (Storz Ophthalmics,St Louis) through the temporal site (Fig 1). The lens was phacoemulsifiedand extracted and an anterior vitrectomy performed with use of a vitrec-tor (Storz Ophthalmics, St Louis) introduced temporally. The instrumentswere withdrawn, the temporal incision was sutured, and a laser probe (IrisMedical Instruments, Mountain View, Calif) was inserted nasally. With useof coaxial illumination through the operating microscope, temporal ciliaryprocesses were treated with the laser, with careful indentation of the globeto permit their visualization (Fig 2). The remaining sclerotomy was thensutured shut and the eye was re-formed with balanced salt solution anddressed with combination antibiotic-steroid ointment.

Two animals were euthanized and the eyes enucleated at each of 5time points: immediately after surgery, and at 1 week, 2 weeks, 3 weeks,

607

Haller

FIGURE 1

Experimental animal protocol. With a 23-gauge butterfly needle introduced through parsplana for infusion, the lens was ultrasonically fragmented and removed and anterior vitrec-tomy was performed.

FIGURE 2Experimental animal protocol. After suturing the right-hand sclerotomy, endolaser probewas introduced through the left-hand sclerotomy. Opposite ciliary processes were broughtinto view by carefully indenting the sclera with cotton-tipped applicator, and then laseredunder direct visualization.

608


and 1 month postoperatively. After enucleation, a small incision was madein the eyes posteriorly to allow for globe perfusion with preservative solu-tion, and they were placed in a glutaraldehyde-formaldehyde mixture .

Eyes were opened by removing the superior cap. They were examinedunder the dissecting microscope, and the posterior pole was removed.They were then processed in standard fashion for light and electron micro-scopic evaluation.

HUMAN EYES

There is no report in the literature of the histopathologic findings inhuman eyes after transvitreal endophotocoagulation of the ciliary process.Files from the pathology laboratory of the Wilmer Institute were reviewedfor cases with a history of endocyclophotocoagulation, and 3 eyes wereidentified, all enucleated for pain. Case histories were obtained, and slideswere pulled for review.

CLINICAL SERIES

Office records of a single surgeon were reviewed to identify patients withtransvitreal laser to the ciliary body. In some of these complicated eyesfrom a wide referral range, adequate postoperative follow-up was notavailable, although referring doctors were contacted. Only patients withfollow-up of 6 months or more were retained in the cohort for analysis. Allpatients had uncontrolled IOP on maximum tolerated medical therapy,had failed previous glaucoma surgery, were not considered good candi-dates for filtering procedures, and/or needed additional surgery that couldreadily be combined with ciliary body endophotocoagulation.

The following parameters were recorded for all patients: age, sex,race, type of glaucoma, number and type of previous operations, numberand type of previous glaucoma procedures, date and details of transvitrealcyclophotocoagulation procedure(s), preoperative and postoperative visu-al acuity, ocular medications, and IOP and postoperative complicationsand further surgery.

Surgical TechniqueSurgery was performed with subjects under sedation and retrobulbaranesthesia, with a 50:50 mixture of 2% lidocaine (Xylocaine) and 0.75%bupivacaine (Marcaine) with hyaluronidase (Wydase) in adults and gener-al endotracheal anesthesia in children. In 5 eyes with opaque corneasscheduled for penetrating keratoplasty at the same time as vitreoretinalsurgery, a corneal button was first removed and an Eckhardt temporarykeratoprosthesis (Dutch Ophthalmics, Kingston, NH) sutured in place.

609

610 Hailer

Conjunctival incisions were made to expose the anterior sclera nasally andtemporally, and sclerotomy sites were prepared 3 mm posterior to the lim-bus in standard three-port vitrectomy fashion. A pars plana lensectomywas performed by ultrasonic emulsification in 7 cases with significant pre-operative lens opacities. In other cases residual cataract remnants presentin the pupillary space, vitreous cavity, and/or overlying the ciliary process-es were removed with the vitrectomy probe. In some early cases pupillo-plasty or sphincterotomies were performed if necessary to widen a smallpupil; in later cases flexible iris retractors (Grieshaber, Switzerland) wereused.

A vitrectomy was then performed. A posterior vitreous detachmentwas present in nearly all cases, and some eyes had been previously vitrec-tomized at least partially. In some cases additional maneuvers such asremoval of vitreous incarcerated in the cataract wound, epiretinal mem-brane peeling, retinal detachment repair, and/or panretinal endophotoco-agulation were carried out, as outlined in Table I. One sclerotomy wasthen closed with a plug, the infusion bottle was lowered to decrease thepressure within the eye, and an endophotocoagulation probe was insertedthrough the other superior sclerotomy. The ciliary processes opposite thelaser probe were visualized in the pupillary space by indentation of thesclera with a cotton-tipped applicator. This was generally best accom-plished by indenting posteriorly until the peripheral retina came into viewand then rolling the applicator anteriorly until the ciliary processes wereseen (Figs 3 and 4). Coaxial illumination from the microscope light wasusually sufficient to allow identification of the ciliary body, but visualiza-tion was better with use of the two-function illuminated laser probe(Infinitech, Chesterfield, Mo) (Figs 3 and 4).

Laser application to the entire anterior-posterior extent of the ciliaryprocesses was applied under direct visualization. In many cases, previoustreatment effects could be observed where prior cryotherapy, transsclerallaser, or transvitreal laser had been performed. Power settings rangedfrom 200 to 700 mW Treatment power and duration were adjusted tocause a color change (whitening followed by -browning) and shrinkage ofthe tissue while minimizing the number of audible pops. The extent oftreatment depended on the past ocular histor including previous surgeryand preoperative IOP. At least 2400 of circumference of the corona ciliariswas included in the initial treatment, typically from the 2-o'clock positionclockwise to 10 o'clock. With re-treatment, it was often necessary to makean additional inferior sclerotomy in order to visualize and treat the superi-or ciliary processes.

Postoperatively, eyes were treated with topical combination steroid

610


TABLE I: CHARACTERISTICS OF EYESWITH ENDOCYCLOPHOTOCOAGULATION

CASE/DX AGE/RACE HISTORY TOTAL #/SEX PREVIOUS

OPS

1 trauma 59 w f trauma, 1cataract opw/vit loss,ABK

2 com- 75wm COAG, 3bined ECCE/IOL/mech filter, repos-

ition IOL,repeat repos-ition, vit heme

3 epith 67w f epithehal 2ingrowth ingrowth

4trauma 48b m pen tx, aph 35 second- 80 w f glaucoma, 2ary angle aphakic,closure expulsive(sac) chor heme6 sac 74 w f cat/AC IOL, 4

PK(PBK)7 trauma 35w m tx, angle 4

recession,pseudophak

8 cnag 85wf NAG, aph, 4PK (ABK)

9 nvg 77w f CRVO, 0NVG

10 trauma 68 w m trauma, 1aphakia,ABK,steriod

responder11 sac 73 w m cat, AC 2

IOL, PBK12trauma 31wm BB taxas 10

child, laterrupturedglobe

13 juvenile 22 w m micro- 3 (Molt &cornea, revision,

cong cat & 1 CC)glau, aphakia

# GLAUCOMA ? PK OPS W/OPS (BEFORE/W ENDO-

ENDOLASER) LASER

0 no removal ofvitreousincarc inwound

1 no removal ofvitreousheme, vitfromwound

0 no removal ofepth dgth,

cryo1 (mit-C) no 0

0 no removal ofresiduallens

material1 (CC) PK before 0

(PBK)1 no 0

1 PK before, 0clear

0 no lensectomy,PRP

0 PK at op TKP, PK,sutureIOL

0 PK before, #2 scrapedfailed band k

2 no lensex (pcrupture),repair irisdialysis

3 no #1 removedMolteno

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Haller

TABLE I: (CONTINUED)

CASE/DX AGE/RACE HISTORY # OPS/SEX

14 epith 80w f epith ingr, 2ingrowth cat w/lost

nucleus, ACIOL

15 uvetic 15 b m JRA, uveitis 8aphakia

16 juvenile 22 w m aniridia 1cong glauco,

cataract17 nvg 84 w m ocular 2

ischemicsyndrome,NVG, catand IOL

18sac 41wf PKx4 (KC), 6cat

19 comb 77 w f COAG, 3mechanism aphakic, PK

(ABK)

20sac 64wm PKx3 7(KC), cat

21 juvenile 45 w m cong glauc, 2cat/IOL,retinal

detachmentw/ PVR

22 sac 68w m PKx3 (infec- 3tious kerati-tis, ulcer x2),

aphakia23 comb 68b f COAG, 4mechanism aphakia, PK

(ABK)24 sac 68wf aphakia, PK 3

(ABK)25 comb 34wf ROP, myo- 2mechanism pia, COAG,

NVI, cat-aract, inf RD

# GLAUC ? PK OPS W/OPS WHEN ENDOLAS

0 no removal ofepith ingr,

cryo

6 (3 CC, 1YAG cyclo)

1

no excision ofpup memb

no lensectomy

0 no resuturedIOL, PRP

2 (1 CC) Pkx4 before 0

1 PK before, TKP, PKfailed, repeatPK at timeof endolaser

5 Pkx3 0(1 w/ 5FU) before

1 no vitrectomy,(1 w/ 5FU) scleral

buckle,epi- andretro-retinal

membraneremoval,C3F8, laser

0 PK x3 before 0

2 (1 CC) PK before 0

2 (1 CC) PK before 0(ABK)

1 no lensectomy,repair ofinf RD

612



CASEIDX AGE/RACE HISTORY # OPS # GLAUC ? PK ops W//SEX OPS WHEN ENDOLAS

26 sac 74wm cat/IOL, 4recurrent

endophthalmitisx3, s/p

vitrectomyx2 w/ intravitantibiotics

27 trauma 63 b m trauma, PK 2(corneal

blood staining)28 juvenile 7 w f cong cat, 2

aphakic29 sac 34w m Reiger's 2

cong breaksin Descemetmemb, PK,cataract

30sac 66wf cat, PK 2(ABK)

31 nvg 73w m NVG, PDR, 1aphakic

32 uveitic 74 w f uveitis, 6exudative RD

(?Coats'),cat/IOL

33 sac 71wm cat surg, 3PK x2 (ABK)

34 sac 77w f cat endoph- 4thalmitis, PKx2(PBK)

35 cnag 69w f NAG, apha- 3kic (ABK)

36sac 75bf ACIOL, 2PK (PBK)

37 sac 62wf PKx5(KC), 10aphakia

38 sac 62 w f PK x2(KC), 4aphakia

39 sac 78w f aph, glauc, 5radiation forptesygium

0 no remove IOL,vitreous bx,intravitrealantibiotics

1 (CC) PK before

1

0

no 0

1 Pkxl before, cat extr,(w/5FU) repeat PK IOL, repeat

w/endolas PK

0 PK before 0(ABK)

0 no removal ofviteous

heme, PRP2 no 0

(1 w/ mito-C1 Baerveldt)

0 PKx2 0before (ABK)

0 Pk x2 before 0

3 PK (ABK) PKw/ endolaser

0 PK (PBK) TKP, IOLw/endolaser XC, PK

4(3YAG. PKx5 01 mit-C) before1 (CC) PK x2

before3

0

no 0

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Haller


CASE/DX AGE/RACE HISTORY # OPS # GLAUC ? PK ops w//SEX OPS WHEN ENDOLAS

40 comb 77 b f COAG, PAS, 3mechanism aphakia41 comb 77b f COAG, 4mechanism PAS, aphakia42 sac 79wf cat/IOL, 3

PK x2 (PBK)43 sac 79 w f cat/IOL, 4

PK x244 cnag 65wf angle 4

closure,cat/IOL,PBK

45 epith 53 w m penetrating 1ingrowth trauma,

radiation,epithelialingrowth,subluxedcataract

46 comb 77w f pigment 2mechanism dispersion

synd, PASaphakia

47 comb 77w f pigment 2mechanism dispersion

synd, PASaphakia

48 sac 75wf cat/IOL, PK 2(PBK)

49cnag 70b m CNAG, cat/ 3IOL, PK

50 trauma 27 h m trauma, 1cat/IOL,ulcer(?HSV)

51 trauma 48 w m trauma, PK 9x6 (corneallac), aphalda

52 trauma 49 w m trauma, PK 3(corneal

scar), ulcer,aphakia

2 no 0

3(1CC) no 0

1 Pk x 2 before 0

0 Pk x2 before 0

3 PK (PBK) TKP, PKw/endolaser

0

1

1

no lensectomyremoval ofepithelialingrowth,fluid-gasexchange,cryotherapy

no 0

no 0

0 PK before(PBK)

3 PK before

1

0

0

no 0

2 (CC) Pk x6 before 0

1 (CC) Pkx2 before,PK

w/endolaser

PK

614



CASE/DX AGE/RACE HISTORY # OPS # GLAUC ? PK oPs W//SEX OPS WHEN ENDOLAS

53 sac 55wm aphakia, 2secondaryACIOL

infect keratitis,PBK

54 sac 58wm cat, PK x2 6(ABK)

55 trauma 73 w f trauma, 1aphakia

56 juvenile 9 w m cong cat, 6glaucoma

57 juvenile 9w m cong cat, 4glaucoma,?PHPV

58sac 44wm PKx4(HSV 7keratitis), ul-cer, aphakia,endophth

59 uveitic 39 w f ankylosing 2spondylitis,

uveitis,aphakic

60 sac 71 wf cat/1OL, ?2endoph,PBK

61 juvenile 2wm cong glauc, 5aphakia, PK

(ABK)62 trauma 68w f cat/IOL, 4

traumaw/loss ofIOL

63 comb 53 w f Reiger's 3mechanism syndrome,

mature cat-aract, PAS

64 sac 71 b m familial 6Chandler'ssyndrome,cat/IOL, PK

x465 sac 73 b f aphakia, PK 3

(ABK)66 nvg 64 b f CRVO, 0

NVG

0 PK w/ PK, IOLendolaser XC, sut IOL

(PBK)

3 (CC) PK x2before

0 no

2 no

2 no

2 Pkx4 before

2 (CCx2)

0

0

0

0

0

no pupillo-plasty

?0 PK (PBK) PKw/endolaser

3 (2 CC) PK before

1 Molteno nofailed

between 2endolasers3(1CC) no

0

0

ICCE (lensblack)

2 Pkx4 #2 TKP,before, 1 ERM peel,

w/endolaser IOL XC, PK#2

1 PKbefore 0

0 no lensectomy,PRP

615

Haller


CASE/DX AGE/RACE HISTORY # OPS # GLAUC ? PK oPs W//SEX OPS WHEN ENDOLAS

67 sac 31 w m PK x3(KC),ulcer perf,cat/IOL

68 nvg 67wf PDR, NVG69sac 35wf PKx5(KC),

aphakia70nvg 71wf PDR, PC

IOL, vit x3(VH, NVI),NVG

71 juvenile 23 w f congenitalrubella,deafness,mental

retardation,congenitalcataract,aphakia

72 juvenile 23 w f cong rubella,deafness,mental

retardation,congenitalcataract,aphakia

73 coag 78 b f COAG,trab/ECCEw/lost lensfragments,vit incarc inwound

6 2 (CC) PK x3 PK, removalbefore, of IOL

failed, #4w/encolaser

0 0 no lensex, PRP8 2 (CC) PK x5 before 0

4 0 no removal ofvitreous

hemorrhage,IOL

6 3

3

no

0 no

1 no removal oflens materialand vitreousfrom wound,secondary

IOL

1

and antibiotic drops and atropine sulfate. After initial experience withpostoperative corneal rejection in 2 eyes with prior penetrating kerato-plasty, eyes with corneal grafts in place received hourly topical steroidsimmediately after surgery. Medications were tapered and discontinuedover several weeks as postoperative inflammation subsided. Glaucomamedications were restarted if the IOP was over 21 mmHg. If the IOPremained markedly elevated despite maximally tolerated medical therapy,re-treatment was recommended. The previously lasered areas were exam-ined and in general re-treated, with extension of treatment superiorly to

616


FIGURE 3Technique of transvitreal endocyclophotocoagulation: After vitrectomy, illuminated laserprobe is used to apply photocoagulation as sclera is indented with cotton-tipped applicator toexpose ciliary processes in pupillary plane.

FIGURE 4

Cross-sectional view of surgical procedure. Scleral indentation permits transpupillary visu-alization and treatment of ciliary processes. This is facilitated by two-function probe thatcombines endoillumination with laser capability.

617

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': 14 J&

411"'_a u

Haller

previously untreated processes.

RESULTS

ANIMAL MODEL

Acute Histopathologic FindingsGross inspection of rabbit eyes enucleated immediately after surgeryshowed ciliary body color change in treated areas with whitening in areasreceiving less intense treatment and light brown coloration with tissueshrinkage in more intensely treated areas (Fig 5). Some residual peripher-al lens fragments remained. In 1 eye, a punctate central defect was pre-sent in the ciliary body, where high focal energy delivery had created a full-thickness loss of tissue.

Light microscopic examination of eyes enucleated immediately after

r-'uUU.K o

Gross appearance of rabbit eye enucleated immediately after laser treatment, looking towardpupil through removed posterior portion of eye. Intense confluent ciliary body destructionis seen at right side of lasered area (arrows), with light brown and white coloration and tissueshrinkage. Less intense white treatment is seen to right, with untreated area of normal cil-iary processes (arrowheads) between treated anterior and posterior porfions.

endocyclophotocoagulation revealed normal untreated ciliary processes(Fig 6) adjacent to treated areas. In treated areas, tissue destruction ofvarying intensity was seen, with some areas of total wipeout of architec-tural features and other portions of recognizable, albeit damaged ciliary

618


FIGURE 6Area of untreated rabbit ciliary body demonstrates normal ciliary process with architecturalfeatures including uninterrupted layers of pigmented and nonpigmented epithelium (smallarrows), normal vascularity, and undamaged stroma (large arrow) (periodic acid-Schiff,x457).

tissue (Figs 7 through 15). Tissue destruction was characterized by loss ofpigmented and nonpigmented epithelium with pale staining of the cells,pigment rounding, and nuclear pyknosis in the moderate-intensity bums,and by necrosis and cystlike deterioration in the higher-intensity lesions.Marked proteinaceous exudate was present with prominent stromaledema. There was vascular congestion and hemorrhage. The edematousstroma featured pigment rounding and clumping with nuclear pyknosis.

Electron microscopic study of the cystlike areas of high-intensity lasershowed total loss of ciliary cellular detail, with pigment dispersion (Fig16). Ultrastructural study demonstrated cellular disruption with loss of cellmembranes, occasional remnants of basement membrane, and ghostlikeprofiles of decaying cellular organelles (Fig 17).

Intermediate Histopathologic FindingsGross examination of eyes enucleated within the first 3 weeks after laser photo-coagulation of the ciliary processes showed inflammatory and healing changes,including fibrous ingrowth at the sclerotomy sites. The ciliary body appearedatrophic in treated areas, and some remnants ofhemorrhage were present.

By light microscopy, treated areas of the ciliary body had no recogniz-

619

Haller

FIGURE 7In contrast to normal rabbit ciliary body in Fig 6, an acute laser lesion is seen here. Extensiveproteinaceous exudate is present, with loss of pigmented and nonpigmented ciliary epithelia,vascular congestion, stromal edema, and nuclear pyknosis in stroma (white arrow) (periodicacid-Schiff x457).

~~~~~~~~ ~ ~ ~ ~~~~~~~~~~~~~ .. ......>,:

* . ... ,,, -1Z5,>.2.:tAi, '.. r- **p

.:' S':::zt' ,,','" -:: *, $

FIGURE 8Acute laser lesion in rabbit demonstrates loss of ciliary processes in more intensely treatedareas. Some remnants with identifiable details persist (arrowheads), albeit with pale stainingof cytoplasm and nuclei, loss of nuclei, separation of nonpigmented ciliary epithelium, andmarked stromal edema with pyknosis (periodic acid-Schifff, x183).

620


C. 9

FIGURE 9Laser lesion (between arrows) in rabbit eye immediately after treatment with stromal edema,proteinaceous exudate, disruption of normal architectural features, and loss of ciliary processdetail and cellularity. Remnants of lens (arrowhead) are present (periodic acid-Schiff,x18I3)

~~~~~~~~~~~~~~~~~~~~~~~~~~~.,1, ... ... ...: .: .3.

FIGURE 10Peripheral margin of acute laser lesion. Near-total ablation ofinner aspects of ciliary process-es is present. A portion of spared ciliary process (arrows) features thickening, smudging ofdetail, and pale staining indicative of cellular damage. Lens remnants are present inferiorly(arrowhead) (periodic acid-Schiff, x183).

621

Haller

FIGURE 11Acute lesion demonstrates loss of epithelia, vascular congestion, hemorrhage (white arrow),exudate (large black arrowheads), stromal edema, and nuclear pyknosis (black arrow) (lenscapsule, small arrowheads) (periodic acid-Schifff, x457).

FIGURE 12Immediately after treatment, rabbit ciliary body shows focal necrosis of tips of ciliary process-es, proteinaceous exudate and hemorrhage (arrowheads), edema and nuclear pyknosis(arrow) (periodic acid-Schiff, x457).

622


.F' ..-FdO_ :s. SF' .. '':.

FIGURE 13Acute high-intensity laser lesion demonstrates total ablation of ciliary processes with tissueloss to level of stroma where there is loss of cellular detail and pyknosis (between arrows)(periodic acid-Schiff, x457).

I

FIGURE 14High-power detail of ciliary process with moderate-intensity treatment immediately aftersurgery shows loss of nonpigmented epithelium, vascular engorgement, congestion, andhemorrhage. Residual pigment (arrows) is present (periodic acid-Schiff, x731).

623

Haller

FIGURE 15Acute severe-intensity burn with wipeout of ciliary processes. Cystic spaces are seen, withproteinaceous exudate, and architectural loss within stroma including edema, rounding up ofmelanocytes, pigment clumping (arrow), pyknosis, and separation from stroma of remainingpigmented layer (periodic acid-Schiff, x183).

FIGURE 16Electron microscopic appearance of high-intensity acute lesion like that seen in Fig 15, show-ing cysticlike remnants where ablation and degeneration of ciliary process has taken place,with loss of cellular detail (x102,512).

624


FIGURE 17Electron microscopic appearance of high-intensity acute lesion shows loss of plasmalemmaand cytoplasmic organelles. Basement membrane (arrowheads) remains. Ghostlike profilesof pale-staining nuclei (arrows) are present (x102,512).

able features but demonstrated total ablation. Pigment dispersion wasprominent. Residual proteinaceous material was found between the treat-ed processes, with destruction of the processes themselves and roundingof pigment. In some areas early fibrous metaplasia could be seen (Figs 18through 20).

Chronic Histopathologic FindingsAt 1 month after surgery, gross inspection of enucleated eyes revealedatrophy of the ciliary processes, with loss of pigmentation and some appar-ent fibrosis.

Light microscopic examination demonstrated total loss of the ciliaryprocesses in some areas of high-intensity treatment, with more moderateeffects at the margins. At the edges of the laser lesions, separation of thepigmented and nonpigmented ciliary epithelium was seen, with pale stain-ing and loss of nuclei. Increased pigment was a prominent feature, freeand in macrophages. Pigment was rounded and clumped. In some areasno processes could be found at all, with loss of all tissue to the level of thestroma, which was markedly swollen with pyknotic nuclei. Fibrocellular

625

Haller

FIGURE 18Lesion 1 week after endocyclophotocoagulation shows focal obliteration of ciliary processeswith formation of large aggregate of pigment and scarring which has gathered iris in pleats.No identifiable ciliary processes are seen. Lens remnants are present (periodic acid-Schiff,x187).

FIGURE 19High-power view of laser lesion at 1 week with destruction of ciliary processes, rounding andaggregation of pigment. Some residual proteinaceous exudate (arrowhead) remains. Thin cel-lular tissue (between arrows) covers portion of inner surface of lesion (periodic acid-Schiff,x457).

626


FIGURE 20

Inner aspect of experimental laser lesion at 1 week. Where ciliary processes are destroyed,pigment clumping is seen. Fibrocellular membrane (between arrows) and lens capsule(arrowheads) line inner surface (periodic acid-Schiff, x731).

membranes were identified, extending over the areas of degenerated cil-iary processes (Figs 21 through 26).

HUMAN EYESCase 1

History. A 71-year-old woman with proliferative diabetic retinopathydeveloped neovascular glaucoma. She had previously undergone panreti-nal scatter photocoagulation and 3 vitreous procedures, the first a vitrec-tomy for nonclearing hemorrhage and the second and third vitreouswashouts with supplemental laser for continued recurrent vitreous hem-orrhaging. Florid neovascularization with angle closure and pressure of 44with loss of all but light perception developed. She underwent vitrectomywith further washout ofvitreous blood and endolaser to the ciliary process-es. The IOP dropped to 5, the eye continued to have severe bleeding, andall light perception was lost. Pain developed and the eye was enucleated 6months after endocyclophotocoagulation (This is patient No. 70 in theclinical series).

Histopathologic Findings. Hemorrhage was present in the vitreouscavity and subretinal space, with marked ciliochoroidal effusion. The reti-na was totally detached. The corneal stroma was quite vascularized, andDescemet's membrane was detached by serosanguinous fluid. The angle

627

r Ankii F -JV

N.''..i k&.

Haller

FIGURE 21One month after treatment, fibrocellular membrane (arrow) gathers partially degeneratedciliary processes into folds (periodic acid-Schiff, x457).

_ . t.~~',' ''. ' s .FIGURE 22

Rabbit lesion at 1 month with destruction of inner portion of ciliary processes (betweenarrows), with accumulation of much free pigment and pigmented macrophages. Outer por-tions of ciliary processes (arrowheads) are more intact, although devoid of nonpigmentedepithelium (periodic acid-Schifff, x457).

628


FIGURE 23High-power view of laser lesion at 1 month shows destruction of ciliary detail with aggrega-tion of melanin pigment (periodic acid-Schiff, x731).

FIGURE 24One month after laser treatment, margin of lesion is present with abrupt transition (arrows)between preserved two layers of epithelium (nonpigmented and pigmented) to right anddestroyed tissue to left on which fibrocellular membrane (arrowheads) is present (periodicacid-Schiff, x457).

629

Haller

FIGURE 25Rabbit laser lesion at 1 month with destruction of inner portions of ciliary processes andaccumulation of pigment (between arrows) and relative preservation of outer portion areas.Thin fibrocellular tissue (arrowheads) covers internal surface of lesion (periodic acid-Schiff,x457).

FIGURE 26Higher-power view of Fig 25 shows fibrocellular membrane (arrow) and adjacent area ofdestruction of ciliary processes with accumulation of pigment (periodic acid-Schiff, x731).

630


was totally closed by peripheral anterior synechiae. The iris showedmarked entropion superiorly, and fibrovascular tissue covered its anteriorsurface. Extensive hemorrhage with variable fibrovascular organizationoccupied most of the vitreous cavity, with membranes extending anterior-ly onto the ciliary body. Treated and untreated areas of ciliary body couldbe identified despite the severe intraocular pathology. In the area of endo-cyclophotocoagulation, the ciliary processes were absent, replaced byatrophic fibrous tissue with minimal vascularity and pigment clumping.Some hemorrhage was present. On the opposite side of the eye, untreat-ed ciliary processes remained intact, with superimposed fibrovascularmembranes (Figs 27 and 28).

Case 2History. A 28-year-old male with congenitally dislocated lens devel-

oped a syndrome of unknown etiology characterized by retinal pigmentepithelial (RPE) scars, RPE hypertrophy, iris neovascularization and neo-vascular glaucoma. He underwent lensectomy, vitrectomy and endopho-tocoagulation of the ciliary processes. The eye became painful, and enu-cleation was performed 11 months postoperatively.

Histopathologic Finding.: Gross examination of the globe disclosed ahazy cornea, shallow anterior chamber, and fibrous tissue over the iris and

t s* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~--za-- --- -- .-s- ---s--- -=--......................... --

......."

FIGURE 27Case 1. Area of cihary body without laser treatment in enucleated eye of 71-year-old womanwith diabetic neovascular glaucoma. Pigmented and nonpigmented cihary epithelia areintact (periodic acid Schiff, x183).

631

Haller

*' '.b. [.r...A_ _ ~~~~~~~~~~~~~~~~~-- . S.... .iS.

FIGURE 28Case 1. Area of ciliary body treatment with destruction of cihary processes, hemorrhage, anddispersion and clumping of pigment (periodic acid Schiff, x183).

ciliary body. Vitreous hemorrhage was present and multiple fronds ofpinkish filamentous material were seen on the equatorial and peripheralretina.

Microscopically a retrocorneal vascularized membrane was seenperipherally. Inferiorly the iris leaflet was encased in this membrane,which extended posteriorly over the ciliary body. Vessels from the scleraextended into this membrane. The angle was completely closed. The reti-na showed extensive degeneration and gliosis, with a shallow posteriorretinal detachment nasally and extensive retinal pigment epithelial degen-eration and drusen scattered throughout. A cellular epiretinal membranewas present, with fronds extending into the vitreous, and vascular tissueextended from the optic nerve head. The ciliary body showed extensiveatrophy and replacement by fibrous tissue with pigment clumping andsome vascularity in treated areas and preserved ciliary processes inuntreated regions (Figs 29 through 32).

Case 3History. A 41-year-old man sustained a ruptured globe at age 11, pri-

marily repaired with a residual corneal scar and cataract. He subsequent-ly underwent cataract extraction and penetrating keratoplasty with IOLinsertion at age 39. This was complicated by IOL displacement and eleva-

632


FIGURE 29Case 2. Enucleated eye of 28-year-old man with glaucoma demonstrates relatively intact cil-iary processes in untreated area (periodic acid-Schiff, x46).

FIGURE 30Case 2. Treated area, with destruction of ciliary processes, scarring and pigment clumping(hematoxylin-eosin, x183).

633

Haller

Arr

7:-$6:*iXv

FIGURE 31

Case 2. Posterior margin of laser lesion (arrow) with abrupt transition to intact pigmentedand nonpigmented epithelia (to right). Near-total ciliary body ablation is seen in upper leftside of picture. Large blood vessel (arrowheads) traverses area. Fibrovascular membrane(M) covers inner aspect of ciliary body (periodic acid-Schiff, x183).

*"'4 ::: e7-- ... ... .. ..

FIGURE 32Case 2. Higher-power view of pars plicata area with destruction of ciliary processes, scarring,and residual pigment in clumps (periodic acid-Schiff, x457).

634


tion of IOP. He then underwent endocyclophotocoagulation, repeatedafter 2 years. The last operation was complicated by retinal detachment,and 2 months later the patient opted for enucleation of the blind, painfuleye.

Histopathologic Findings. On gross examination, the corneal graft washazy. The IOL was in the ciliary sulcus and subluxated. Multiple areas ofciliary body atrophy and hypopigmentation were seen, with pigmentarypeppering . An inferonasal retinal detachment was present, with a slitlikeretinal hole 1.5 mm inferotemporal to the optic nerve head.

Microscopically, corneal stromal edema was seen, with a thick retro-corneal membrane covering recipient cornea and extending over the tra-becular meshwork and into the angle. Cataractous lens remnants werepresent. The ciliary body was largely destroyed with loss of the ciliaryepithelia and fibrosis of both the pars plicata and pars plana nasally andtemporally. In some areas an extensive fibrocellular membrane coveredmuch of the degenerated ciliary body. The space occupied by the hapticwas present in the ciliary body at the ciliary sulcus, surrounded by thinfibrous capsule with multinucleated giant cells (Figs 33 through 38).

CLINICAL SERIESThe 73 patients studied ranged in age from 2 to 85 years (mean, 57.7 years±22) (Table I). Sixty (82%) were white and 42 (57.5%) female. The num-

FIGURE 33Case 3. Area with discrete laser lesion in pars plana (between arrows). Here epithelial lay-ers are destroyed and replaced by scar tissue (arrowhead) (periodic acid-Schiff, x46).

635

MA

636 Haller

:.',.............

N~ ~ ~ ~ ~ N

_~~~~~~~~~~~~~~~~~~~1.~T R I|* 7_I * | I | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~...........* : y I - | I | I ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~............I1...,','s,_l l l | l ................ -:i3111i .x~~~~~~~~~~~~........*.:.: .. ''' -'-''-i . $.S l - l l | l l ......~~~~~~~~~~~~~~~~................. .... i,,'

FIGURE 34Case 3. Area of treatment with destruction of ciliary processes and scamrng (betwee~narrows). A 0.7-mm area of preservation of cihary epitheha is present in anterior aspect ofpars plana (between small arrowheads). Posteor to this pars plana epitheha (large arrowhead) are destroyed (hematoxylin-eosin, x46).

FIGURE 35Case 3. High-power view of area of destruction of ciliary processes and inner portion of cil-iary muscles with replacement by fibrovascular scar. Segment of thickened basement mem-brane ofpigmented ciliary epithelium (arrow) is present in scar (periodic acid-Schiff, x457).


FIGURE 36Case 3. Untreated area of ciliary body with intact ciliary processes (periodic acid-Schiff,x46).

FIGURE 37Case 3. Area of treatment with loss of ciliary processes (between arrows). Posterior extent oflaser treatment is present in posterior aspect of pars plana (arrowhead) (periodic acid-Schiff,x46).

637

O""IN

r.4k

Haller

h.. *

-,

FIGURE 38

Case 3. High-power view of pars plicata shows destruction of ciliary processes.Fibrovascular tissue and some proteinaceous material (between arrows) covers internalaspect of lesion. There is loss of inner portion of ciliary muscles. Vascular layer (betweenarrowheads) is present. Vitreous is adherent in area of lesion (V) (periodic acid-Schiff,x457).

ber of previous operations ranged from 0 to 10 (mean, 3.5 operations±2.2), and the number of previous glaucoma operations ranged from 0 to6 (mean, 1.3 operations ±1.3). Comparison of the groups with Student's t-test showed no significant difference in number of operations (P=0.1720)or glaucoma procedures (P=0.2734) between men and women. Blacks hadundergone a mean of 3.25 previous operations compared with 3.53 oper-ations for whites (P=0.69), and a mean of 1.83 glaucoma operations com-pared with 1.18 for whites (P=0.12). All eyes were complicated.

Table II outlines the major diagnostic categories and subdivides thegroups with respect to whether or not cataract surgery and/or penetratingkeratoplasty had been performed. Patients were divided into the followingdiagnostic categories in terms of their glaucoma: secondary angle closure(27 eyes, 23 with prior penetrating keratoplasty [PK], 15 aphakic, and 11pseudophakic), angle damage from trauma (11 eyes, 7 aphakic, 3pseudophakic, and 3 after PK), combined mechanism (9 eyes with chron-ic open-angle glaucoma and a superimposed component of secondaryangle closure, 6 aphakic, 1 pseudophakic, and 2 after PK), juvenile glau-coma (9 eyes, 8 aphakic and 1 pseudophakic), neovascular glaucoma (6

638


TABLE II: CATEGORIES OF PATIENTS UNDERGOING

ENDOCYCLOPHOTOCOAGULATION

GLAUCOMA NUMBER OF # PHAKIC # APHAKIC # PSEUDO- # PREVIOUS

DIAGNOSIS EYES PHAKIC PK

Secondary 27 1 15 11 23angle closure

Trauma 11 1 7 3 3

Combined 9 2 6 1 2mechanism

Juvenile 9 0 8 1 0

Neovascular 6 3 1 2 0

Chonic 4 0 2 2 1narrow angle

Uveitic 3 0 2 1 0

Epithelial 3 1 0 2 0ingrowth

Chronic open 1 0 1 0 0angle

eyes, 1 aphakic and 2 pseudophakic), chronic narrow-angle glaucoma (4eyes, 2 aphakic and 2 pseudophakic), uveitic glaucoma (3 eyes, 2 aphakicand 1 pseudophakic; 1 patient had ankylosing spondylitis, and 1 juvenilerheumatoid arthritis), glaucoma associated with angle damage fromepithelial ingrowth (3 eyes, 2 pseudophakic), and chronic open-angle glau-coma (1 aphakic eye)(Table II).

Table III outlines follow-up data, IOP results, and visual acuity results.Follow-up ranged from 6 to 130 months (mean, 28.6 mo ±29).Preoperative intraocular pressure ranged from 19 to 75 mmHg (mean, 38mmHg). Postoperative IOP at 6 months ranged from 3 to 42 mmHg(mean, 15.4 mmHg); at 12 months the range was 2 to 40 mmHg (mean,15.5 mmHg). At final follow-up, IOP ranged from 1 to 50 mmHg (mean,16.0 mmHg), including all eyes whose last glaucoma operation was endo-cyclophotocoagulation (thus excluding 8 eyes that subsequently under-went other pressure-reducing proceduresi.

Patients preoperatively took a mean of 2.48 (±1.06) glaucoma med-

639

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TABLE III: RESULTS OF ENDOCYCLOPHOTOCOAGULATION

NAME VA VA IOP IOP 6 iop 12 IOP # MEDS # MEDS F/U,PREOP POST PREOP MO MO LAST PREOP POST COMP-

F/U LICS

1 LP NLP 45 lost to lost to 50 1f/u f/u

2 20/200 20/160 26 17 na

3 20/150 HM 63 5 na

4 20/300 20/300 48 18 na

5 LP 1/200 43 17 17

6 20/50 20/40 35 12 15

7 20/200 20/400 31 14 21

8 5/200 5/200 33 7 7

9 HM HM 30 11 20

10 CF 2/200 24 1911 HM LP 52 12 10

12 HM 20/400 49 15 na

13 20/300 1/200 30 20 21

14 20/150 LP 25 24 8

15 LP 20/400 32 17 21

16 5/200 20/100 32 10 18

17 4/200 20/50 38 10 12

18 20/50 20/200 45 13 11

43m176m 256m 2

186m 117 248m15 414m21 322m22 316m20 012m196m 18 24m 2

157m 310* 299m°Mol-teno21 225m21 213m13* 1130 m°Kru-pinvalve18 216m12 325m

0 lost tof/u

10 recur-

rence ofepithingrwth

10

1 PK clr

0

0 PK clr

0

0 PK0 x2, PK

failed21 x3(#1

failed@82m)*Molt

2

1

0° x3(#1/2failed @81m,#3@14m)*Krupn

0

0 x2,PKrej@3mclearedthenfailed@2y

640

Transvitreal Endocyclophotocoagulation6

TABLE III: (CONTINUED)

CASE VA VA IOP IOP 6PRE POST PRE MO

iop 12 lOP # MEDS # MEDS F/U,MO LAST PRE POST COMP-

F/U LICS

19 CF HM 35 2320 5/200 HM 58 25

21 1/200 20/80 22 1022 HM HM 47 14

23 20/400 CF 42 12

24 20/400 20/200 42 2025 5/200 20/400 45 11

26 LP NLP 45 34

27 LP HM 38 15

28 20/60 20/40 40 20

29 CF 20/250 32 7

30 20/60 6/200 43 10

31 HM 20/400 46 16

32 HM HM 34 5

33 HM HM 37 834 6/200 HM 30 1135 HM HM 64 8

36 HM 3/200 40 18

37 20/40 20/50 41 8

na 209m 340° 42t 3*cyclo- 14mcryo xl tcyclo

cryo x210 6 15m 217 17 2

15m

14 10 325m

10 108m 312 10 3

45mna 4° 8m 1

°trabecw/5FU

15 13 424m

16 18 228m

na 76m 2

na 10 3lrm

15 13 218m

na 5 36mo

7 427m 3na 119m 317 17 1

12m19 19 1

12mok 19 3

33m

1 PK clr2 cyclo-

cryo x2failedPK

01 rej5m

postopcleared,PKfailed@13m

1 @12mPKfailed

0 PK clr1

0 SFUtrabw/chorhem,rd@7m

2 PK clr

0

0 PK rej@2mo

2 PK rej

0 x2

0 fibrinafter allops,periphchor

0 PK clr0 PK clr0 PK

0 PK

1 PK

641

Haller

TABLE III: (CONlINUED)

CASE VA VA IOP IOP 6 ioP 12 IOP # MEDS # MEDS F/U,

PRE POST PRE MO MO LAST PRE POST COMP-

F/U LICS

38 HM HM 33 9

39 20/100 20/80 40 14

40 20/60 20/50 35 22

41 5/200 20/70 25 2442 CF HM 39 14

43 HM HM 46 12

44 HM HM 19 30

45 HM 20/200 35 19

46 20/200 20/50 35 32

47 20/100 HM 28 19

48 20/300 20/400 32 12

49 8/200 20/100 26 10

50 20/250 20/100 29 1851 5/200 6/200 24 952 HM 20/25 35 12

53 1/200 20/100 23 2154 20/300 20/60 42 10

55 20/300 20/100*32 12

56 20/100 20/100 40 21

57 CF CF 38 14

ok 19 3 0 PK32m

16 16 212m

na 20 9m 4

na 24 6m 318 14 3

81m

13 13 313m

na 28 7m 2

19 19 225m

16* 10* 414m'trabecw/mitC

2 34 414m

14 12 420m

25 17* 330m

na 18 3m 210 8 31m 310 10 3

12mna 21 7m 217 16 2

37m14 13 4

17m

17 13* 396m°Krupn

16 17 396m

2 periphchor

20 rerx

@75m,PKfailed

1 PK

2 PKfailed

1

1 x2trab/mitC@9m

2 x2

1 PK clr

0 *cc@lyPK cl

00 PK clr3 PK clr

2 PK clr0 PK clr

1 *20/60,thenmacularhole

3 x2,2@43m,then Kr@36m

4

642


TABLE III: (CONTINtUED)

CASE VA VA lOP IoP 6 IoP l2 IOP #MEDS #MEDS FAU,PRE POST PRE MO MO LAST PRE POST COMP-

F/U LlCS

58 4/200 HM 50 20

59 HM HM 25 6

60 LP HM 75 6

21 22* 426m*0meds

16 1° 346m*+/-w/uveitis

7 9 13m 0

61 CF CF 35 14 18 16 340m

62 HM HM 38 38 32° 14f 3°fafled 33mMol- fendo-teno laser #2

63 LP NLP 30 3 2 1 49m 2

64 20/400 HM 40 8 8 6 85m 2

65 20/300 HM 32 20 21 23 419m

66 HM HM 58 12 15 22 427m

67 HM HM 34 10 na 106m 0

68 HM 20/50 55 15 16 16 214m

69 HM HM 40 21 21 24 3

70 LP NLP 44 5 na**enuc

for pain

31m5 26 mo

0 conjflap,failedPK

0 stableeyeNA,IOP+/-w/uveitis

0 @lOm:PK, epi-ciliarymemberremoval,PKfailed

1 failedPK

3 #1 failedthen Mfailed,then #2success

0 chorhem,phthisis

0 x2,PKx2

0 rerx,periphchor,PK clr

0 fibrin

0 periphchor,PK clr

0 fibrin

1 PKfailed

0 enuc forpain

6143

Haller

TABLE III: (CONTINUED)

CASE VA VA IOP IOP 6 ioP 12 IOP # MEDS # MEDS F/U,PRE POST PRE MO MO LAST PRE POST COMP-

F/U UCS

71 20/200 20/200 37 22 18 21 4 4 x2, #2117m @

69m72 20/200 CF 35 21 23 74

121m x3,#2@'Krpn, 70m,#3postop @llm,chor kr@heme 17m w/

chorheme,GRT

73 20/400 20/60+ 25 14 16 15 0 028m

ications (range, 0 to 4), postoperatively decreasing to a mean of 0.78(±1.09) medications (range, 0 to 4). Thirty-six patients were able to stop allmedications, including oral carbonic anhydrase inhibitors.

Results were analyzed in terms of a successful outcome, defined asIOP greater than 5 mmHg and less than 22 mmHg. For this analysis, anyeye that underwent further glaucoma surgery other than re-treatment withendolaser was immediately classified as a failure.

At 6 months, 58 of the 72 eyes with available data were successful bythese criteria (81%). At 12 months, 48 of the 55 eyes with available datawere considered successful from the IOP standpoint (87.3%).

At last follow-up visit, data on all 73 eyes were analyzed for success ofIOP control. Fifty eyes maintained IOP greater than 5 mmHg and lessthan 22 mmHg (68%), with a mean of 28.6 months' follow-up. Four eyeshad IOPs that were chronically in the successful range, but at the lastrecorded pressure check were charted as IOP 22 to 23 (3 with IOP 22, 1with IOP 23), were on no pressure medications, and considered stable.Two eyes with uveitis had fluctuations of pressure into the hyptonousrange with inflammatory bouts and at last measurement had IOP of 1 and5, but with stable vision and anatomy. If the definition of "success" isexpanded to include these 6 eyes, 56 of 73, or 77%, of eyes treated withendocyclophotocoagulation would be considered clinically stable at lastfollow-up.

Visual acuity data was analyzed to determine whether patients

644


improved, stayed the same, or worsened when last follow-up was com-pared with preoperative vision. Loss of vision was defined as doubling ofthe visual angle (as from 20/40 to 20/80, or from 20/200 to 20/400), andimprovement of vision was defined as halving of the visual angle. Changesless than this were considered no change. Visions recorded as "count fin-gers" were considered equivalent to 5/200 (or 20/800). A drop in visionfrom count fingers to hand motions was considered a doubling of the visu-al angle; acuity loss from hand motions to light perception and from lightperception to no light perception was similarly classified.

At last follow-up, visual acuity was the same as preoperatively in 30 of73 eyes (41%), better in 23 (32%) and worse in 20 (27%).

The 20 eyes with visual loss are further detailed in Table IV. In 8 cases,visual loss was primarily from corneal clouding, despite adequate pressurecontrol (1 eye failed endolaser but was controlled with a Molteno implant).In 4 cases visual loss was from progression of underlying disease process-es: recurrent epithelial ingrowth, chronic cystoid macular edema (whichresolved when the eye stabilized after successful laser to the ciliary body),epimacular membrane with visual loss that did not recover despite suc-cessful removal, and uncontrollable progressive proliferative diabeticretinopathy leading to a blind, painful eye and enucleation. Four patientslost vision primarily owing to failure to control IOP: one who did notreturn for follow-up until 43 months postoperatively, at which time all lightperception had been lost; 1 with successfully treated epithelial ingrowthwho refused further glaucoma surgery; one who gave up on the eye after9 failed glaucoma operations, including 2 cyclocryotherapies afterendolaser to the ciliary body; and 1 with aphakia and pigment dispersionsyndrome who elected not to have further surgery when vision dropped tohand motions. The final cause of visual loss was surgical complications in4 eyes, 1 of which sustained a choroidal hemorrhage at the time of intra-capsular cataract extraction performed before beginning endolaser to theciliary body. The hemorrhage cleared, no retinal detachment developed,and the IOP was controlled, but the eye never recovered. The 3 remain-ing eyes had visual loss from a conjunctival flap (IOP controlled), fromchoroidal hemorrhage and retinal detachment developing after subse-quent trabeculectomy with adjunctive 5-fluorouracil treatment, and fromchoroidal hemorrhage (successfully drained) after subsequent Krupinvalve placement.

ComplicationsComplications of endocyclophotocoagulation are analyzed in Table V.Nine eyes (12%) developed complications. Hypotony (defined as IOP<6

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TABLE IV: VISUAL LOSS AFTERENDOCYCLOPHOTOCOAGULATION

CASE# AGE SURG HX VA PRE/ IOP PRE/ REASON FOR

(YR) POST POST LOST VA

1 1 59 trauma, cat op LPw/vitreous loss, NLPABK

2 3 67 cataract 20/15surgery, then HMepithelial in-growth aftersecondary ACIOL withwound leak

45 corneal edema,50 (43 mo) glaucoma

0 635 (6mo)

recurrent epithingrowthw/cryo, cornealdecomp, lowIOP

3 7 35 BB trauma, 20/200 31 chronic CMEangle reces- 20/400 21 (22mo) resolvedsion, cataract leavingop, secondary macularIOL, IOL ex- pigmentarychange, trabec- changesulectomy, RD

4 11 73 cataract w/ AC HM 52 graft failedIOL, PBK, PK LP 8 (24mo) before endo-w/IOL XC, laser, but VAfailed graft, dropped furtherneeded endo- as PK becamelaser x2 more cloudy

w/bandkeratopathy

5 13 22 congenital cat 20/300 30 IOP good afterand glaucoma, 1/200 10* (99mo) endolaser #1microcornea, 'after Molteno for 6 yr 10 mo,(fellow eye tube #2, placed but then repeatenucleated for 9 mo after last treatment didglaucoma) s/p endolaser not adequately3 glaucoma ops control IOP,(Molteno #1 and Moltenoplaced, revised, #2 placed. VAthen removed; loss from cor-cyclocryo) neal decomp,before endo- IOPlaser, thenendolaser x3

646A


TABLE IV: (CONTINUED)

CASE# AGE SURG HX VA PRE/ IOP PRE/ REASON FOR

(YR) POST POST LOST VA

6 14 80 s/p cataract 20/150 25 IOP, cornealsurgery 20/400 48 (11 mo) decompcomplicated bylost nucleus, ACIOL, epithehalingrowth

7 18 41 s/p PK x3 for 20/50 45 graft rejectionkeratoconus, 20/200 12 (25 mo) treated withcataract op, steroids, butcyclocryo residual corneal

edema8 20 64 PK for kerato- 5/200 58 graft failed, IOE

conus, ALT x2, HM 42 (14 mo) uncontrolledPK#2, ECCE, (despitetrabec, orbit bx cyclocryo x2lymphoid postop (total 9hyperplasia), PK failed glaucoma#3 w/IOL and ops)trabec, en-dolaser x2

9 23 68 aphakic 20/400 42 graft edema 12glaucoma, s/p CF 10 (25 mo) mo afterPK for ABK, 3 endolaserfailed glaucomaops (1 cyclocryo)

10 26 74 postcataract LP 45 choroidalendophthalm NLP °4 (8 mo) hemorrhage anc(cultured yeast, 'after trabec w/ RD after trabecstaph, and 5FU complic- w/5FUanother gram ated by chor-pos organism), oidal hemor-recurrent x3 rhage and RDdespite vtx w/intravit anti-biotics

11 30 66 aphakic, s/p PK 20/60 43 graft rejectedfor ABK 6/200 10 (11 mo)

12 34 77 post cataract 6/200 30 graft edematousendophthalm, HM 11 (9 mo)IOL repos-itioning, PK forPBK (rejected),PK x2, age-related maculardegeneration

647

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TABLE IV: (CONTINUED)

CASE# AGE SURG HX VA PRE/ IOP PRE/ REASON FOR(YR) POST POST LOST VA

13 42 79 s/p cat/IOL, PKx2 for PBK, filter

14 47 77 pigmentdispersionsyndrome,aphakic, ALT

15 58 44 PKx4 forHSVkeratitis, ulcer,endophthalm

16 63 53 Reiger's syndr,high myopia, s/p3 failed glaucomaops, dense blackcataract removedat time ofendolaser surgery(unable to phaco,so removed intra-capsularly)

17 64 71 Chandler'ssyndrome, PKx4, cat/IOL,endolaser x2 (#2combinedw/repeat PK andERM peeling,but VA neverimproved past HM

18 65 73 s/p ICCE, PK forABK, trabecneeded endolaserx2

18 70 71 PDR, PC IOL, vitx3, vit hem,NVG

20 72 23 cong rubella,deafness, mentalretardation, congcataract, aphakia

CFHM20/100HM

3914 (81 mo)2834 (14 mo)

graft edematous

glaucoma

4/200 50 conjunctival flapHM 22 (26 mo) over cornea

LPNLP

30 choroidal1 (49 mo) hemorrhage

intraop afterICCE withgradual clearingover severalmonths, no RD,but eye becamephthisical

20/400 40 ERM peeled, butHM 6 (85 mo) VA never

improved (HMbefore op)

20/300HM

LPNLP

20/200CF

3223 (19 mo)

graft edematous

44 severe diabetic5 (6 mo) proliferative

disease35 Krupin valve7 (121 mo) placed @17mo

postopw/choroidal hem,giant retinal tear(lasered)

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TABLE V: COMPLICATIONS AFTER


n= 73

Hypotony 6 (8.2%)(IOP<6 at last visit)

Choroidal detachment 4 (5.5%)tperipheral)

Fibrin reaction 3 (4.1%

Phthisis 2 (2.7%)

Hemorrhagic choroidal 1 (1.4%)

Eyes with complications 9 (12%)

Complications with penetrating keratoplasty

Graft rejection (n=35) 4 (11%)

Graft failure (n=35) 11 (31%)

mmHg) developed in 6 eyes (8.2%) after endolaser treatment. Two ofthese eyes were anatomically and visually stable but had bouts of uveitisassociated with low pressures. Another eye was stable, maintained preop-erative vision, and had a clear corneal graft with IOP of 4. One eye hadrecurrent epithelial ingrowth, 1 eye became phthisical after choroidalhemorrhage associated with the intracapsular cataract extraction (ICCE)prior to endolaser, and a final eye suffered progressive intraocularfibrovascular proliferation, hemorrhage, and phthisis secondary to uncon-trollable diabetic retinopathy.

Shallow peripheral choroidal detachments developed in 4 patients(5.5%), 1 with uveitis. These resolved spontaneously in all instances.

Postoperative anterior segment inflammation with fibrin depositionoccurred postoperatively in 3 patients (4.1%), 2 with neovascular glauco-ma and 1 with uveitis (who had experienced fibrin reactions after all pre-vious operations). Tissue plasminogen activator was injected in 1 case toaid clearance. All eyes were treated with topical steroids, and all inflam-

649

650 Haller

mation cleared .Phthisis developed in 2 eyes (2.7%), both previously discussed. One

sustained an intraoperative choroidal hemorrhage after ICCE, and 1developed progressive diabetic proliferative disease and hemorrhage andcame to enucleation.

Choroidal hemorrhage developed in the 1 eye (1.4%) with highmyopia, uncontrolled IOP, Reiger's syndrome, and dense black cataractthat underwent ICCE before endolaser after the transvitreal ultrasonicfragmentor proved unable to break up the lens. Hemorrhaging developedas endolaser was beginning.

There were 35 eyes in this series followed after penetrating kerato-plasty, which collectively had undergone a total of 75 corneal transplants(an average of 2.14 each). Graft rejection developed in 4 eyes (11.4%).After 2 of these episodes, more vigorous postoperative steroid coveragewas initiated in eyes with corneal grafts, but 2 more eyes developed rejec-tion episodes nevertheless. The rejection episodes cleared with steroids in2 cases, but the grafts later failed.

In addition to the 4 eyes with rejection episodes, 7 additional eyes hadnonimmunologic progressive corneal clouding for a total of 11 eyes (31%)with graft failure.

Subgroup Analysis ofResultsGlaucoma Diagnosis. Table VI provides a detailed breakdown of suc-

cess rates by glaucoma diagnosis.Eyes with secondary angle closure were successfully treated (IOP >5

mmHg and <22 mmHg) in 93% of cases at 6 months, 91% at 12 months,and 78% at last follow-up (85% if 2 stable eyes off medications with lastrecorded IOPs of 22 and 23 are included). Vision was improved or stablein 19 of 27 eyes (70%), with most visual loss due to corneal graft failure.

Eyes with posttraumatic angle damage had successful IOP control in9 of 11 eyes (82%) at 6 months, 5 of 6 (83%) at 12 months, and 10 of 11(91%) at last follow-up. Vision was preserved or improved in 82%.

Eyes with juvenile glaucoma did well initially, with 8 of 9 (89%) suc-cessfully controlled at 6 months and 12 months, but only 5 of 9 (56%) atlast follow-up. Maintenance or improvement in vision was achieved in 7 of9 (78%).

Eyes with chronic open-angle glaucoma and some degree of superim-posed secondary angle closure (combined mechanism) were successfullycontrolled in 4 of 9 (44%) at 6 months, 2 of 5 (40%) at 12 months, and 4of 9 (44%) at last follow-up. Vision stabilized or improved in 5 of 9 eyes(56%).

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TABLE VI: RESULTS AFTER ENDOCYCLOPHOTOCOAGULATION BY DIAGNOSIS

DIAGNOSIS 5<iop<22 5<iop<22 5<iop<22 SrBLE OR COMMENTS@6 MO @12 MO @LAST F/U IMPROVED

VA

Secondary 25/27 (93%) 20/22 (91%) 21/27 (78%)@ 19/27 (70%) °2 stableangle closure (@23/27, 85%) w/1OP 22,23

w/no meds

Post- 9/11 (82%) 5/6 (83%) 10/11 (91%) 9/11 (82%)traumatic

Juvenile 8/9 (89%) 8/9 (89%) 5/9 (56%) 7/9 (78%)

Combined 4/9 (44%) 2/5 (40%) 4/9 (44%) 5/9 (56%) 41 stable eyemechanism (°5/9,56%) (°5/9,56%) w/IOP 20 off

meds

Neovascular

Chronicnarrow angle

Uveitic

5/6 (83%)

3/4 (75%)

2/3 (67%)

Epithelial 2/3 (67%)ingrowth

Chronic open- 1/1 (100%)

5/6 (83%)

2/4 (50%)

2/34 (67%)41 case w/IOP 5

2/3 (67%)

1/1 (100%)

4/64 (67%) 5/6 (83%) 'lease w/IOP(@5/6,83%) 22 on no meds

1/4 (25%) 4/4 (100%) °1 case w/IOP(@2/4 50%) 20 on no meds

1/3 (33%) 3/3 (100%) 'note 2 stable(@3/3, 100%) eyes despite

IOP 1, 5 dueto uveitis

2/3 (67%) 0/3 (0%)

1/1 (100%) 1/1 (100%)angleglaucoma

Aphak/pseudo- 54/65 (83%) 45/51 (88%) 45/65 (69%) 53/65 (82%) @49/65 count-phakic eyes (@49/65, 75%) ing 4 stable

eye on nomeds w/lastIOP 22, 22, 1,

5

Eyes with PK 32/35 (91%) 26/28 (93%) 27/35 (77%) 25/35 (71%) @3 stable eyes(@30/35,86%) w/IOP 22, 22,

23 on no meds

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Neovascular glaucoma results showed 5 of 6 eyes (83%) in good con-trol at 6 months and 12 months, and 4 of 6 (67%) in good control at lastfollow-up (5 of 6, or 83%, if a stable eye off medications with IOP 22 isincluded). Vision was stable or improved in 5 of 6 (83%).

The eyes with chronic narrow-angle glaucoma achieved good IOPcontrol in 3 of 4 (75%) at 6 months, 2 of 4 (50%) at 12 months, and 1 of 4(25%) at last follow-up. All 4 maintained vision.

Uveitic eyes were successfully managed with endolaser to the ciliarybody, although IOP fluctuations below 10 mmHg occurred. Two of 3 eyes(67%) had IOP .5 and <22 at 6 months and 12 months (3 of 3 if a stableeye with IOP 5 included), and 1 of 3 at last follow-up (3 of 3 if includingthe 2 eyes with IOP 1 and 5 who remained stable). All eyes maintainedpreoperative visual levels or improved.

Eyes with epithelial ingrowth had good IOP control at all time pointsin 2 of 3 (67%), but all lost vision.

The 1 eye with chronic open-angle glaucoma had successful IOP con-trol at all time points, with improvement in vision.

Aphakic and pseudophakic eyes had successful IOP control in 54 of 65cases (83%) at 6 months, 45 of51 (88%) at 12 months, and 45 of 65 (69%)at last follow-up (75% if 4 stable eyes off medications are included withLOPs 1,5, 22, and 22 mmHg). Eighty-two percent maintained or improvedtheir preoperative level of vision.

Eyes with penetrating keratoplasty did exceptionally well in terms ofpressure control. At 6 months, 32 of 35 (91%) were in good range, at 12months 26 of 28 (93%), and at last follow-up 27 of 35 (77%). Thirty of 35eyes (86%) were considered clinically stable, including 3 eyes off glauco-ma medications with LOPs 22, 22, and 23 mmHg. Vision was maintainedor improved in 25 of 35, or 71%.

Numbers in the subsets were subjected to statistical analysis to deter-mine if statistically significant differences in success rates could be found.Numbers were too small and success rates too similar to achieve statisticalsignificance. The groups of patients with secondary angle closure and withpenetrating keratoplasty (which overlapped considerably), however, tend-ed to have a very high rate of pressure control.

Cases Requiring Further Surgical InterventionNineteen cases (26% of total group) that required further surgical inter-vention after initial treatment with endolaser to the ciliary body aredetailed in Table VII.

In 16 of 19 eyes (84%), reintervention was necessary because the ini-tial laser treatment of the ciliary processes was inadequate to cause suffi-

652


TABLE VII: CASES REQUIRNG FURTHERSURGICAL INTERVENTION

CASE #IDX REASON FOR OPERATION OUTCOMEFURTHER SURG PERFORMED

1 3 epith ingr recurrence of epith repeat cryotherapy HM VA, IOP 5 (6 mo)ingrowth

2 11 sac uncontrolled IOP rx#2 IOP 8 (24 mo)

3 13 juvenile uncontrolled IOP rx#2 @82 mo, then #3 lOP 10 (99 mo)failed, then Molteno

tube #2 (#1 removed atfirst endolaser

4 16 juvenile uncontrolled IOP rx#1 and #2 (within 1 IOP 13 (130 mo)mo) failed at 81 mo, #3failed after 14 mo, thenKrupin valve placed

5 18 sac uncontrolled IOP xx #2 IOP 12 (25 mo)

6 20 sac uncontrolled IOP cyclocryotherapy x2 IOP 42 (14 mo)

7 26 sac uncontrolled IOP trabeculectomy lost LP after choroidalw/5 f-U hemorrhage, ret detach-

ment, IOP 4 (8 mo)

8 31 nvg uncontrolled IOP rerx IOP 13 (18 mo)

9 42 sac uncontrolled IOP rerx@75 mo IOP 14 (81 mo)

10 46 combined uncontrolled IOP rx #2, then IOP 10 (14 mo)trabeculectomy withmitomycin C @ 9 mo

11 47 combined uncontrolled IOP rx #2 IOP 34 (14 mo)

12 49 cnag uncontrolled IOP cyclocryotherapy @ 12 mo IOP 17 (30 mo)

13 56 juvenile uncontrolled IOP rx #2 @ 43 mo, then IOP13 (96 mo)Krupin after 36 mo

14 60 sac failed gaft, pupillary repeat PK, excision of IOP 9 (13 mo)/cycitic membrane membranes

15 62 trauma uncontrolled IOP Molteno failed, then rx #2 IOP 14 (33 mo)

16 64 sac uncontrolled IOP, failed rx #2, repeat PK x 2 IOP 6 (85 mo)graft

17 70 nvg pain, NLP enucleation comfortable

18 71 juvenile uncontrolled IOP rx #2 @69 mo IOP 21 (117 mo)

19 72 juvenile uncontrolled IOP rx #2 @ 70 mo, #3 after choroidal hemorrhage11 mo, Krupin after 17 requiring drainage, then

more mo giant retinal tear lasered,IOP 7 (121 a mo), VACF

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cient pressure lowering. Thirteen of these 16 eyes underwent retreatmentwith endocyclophotocoagulation, and 3 eyes had 3 treatments each (alleyes with juvenile glaucoma). The remaining 3 eyes had alternative glau-coma procedures after initial failure of endolaser: cyclocryotherapy in twocases with poor visual potential (successful in one) and trabeculectomywith 5-fluorouracil in the last case, complicated by choroidal hemorrhageand loss of light perception.

Of the 13 eyes with elevated IOP that were re-treated with endocy-clophotocoagulation, 7 (54%) were successfully controlled (1 after aMolteno device, implanted between the 2 endolaser procedures, hadfailed), and 1 eye failed repeat endolaser with no further surgery per-formed. The other 5 eyes all achieved IOP control after alternative pres-sure-controlling procedures were performed, 3 with Krupin valve place-ment (1 complicated by choroidal hemorrhage with visual loss), 1 with aMolteno implant, and 1 with trabeculectomy and adjunctive mitomycin-C.Three eyes required later surgery despite pressure control, 1 for recur-rence of epithelial ingrowth, 1 for a pupillary membrane and failed graft,and 1 which was enucleated for pain.

Endocyclophotocoagulation Combined With Vitreoretinal SurgeryFifteen eyes presented with a complicated constellation of problemsincluding uncontrolled intraocular pressure. In these eyes, endophotoco-agulation of the ciliary processes was performed at the same time as othervitreoretinal surgical maneuvers. The cases are listed in more detail inTable VIII. In 5 cases, IOP elevation compounded problems caused bycomplications of anterior segment surgery (loss of lens nucleus, vitreousincarceration in the wound, epithelial ingrowth, and endophthalmitis). In3 cases, panretinal scatter photocoagulation was performed to control neo-vascularization at the same time as endolaser to the ciliary processes, withlensectomy in 1 case and with repositioning of the IOL in another. Threecases had retinal pathology requiring attention: retinal detachment withproliferative vitreoretinopathy in 1 case, inferior retinal detachment in 1case, and epiretinal membrane in 1 case, which also required repeat PKand IOL exchange. Two cases were primarily operated on for IOP controlbut underwent other procedures at the same time: lensectomy and repairof iris dialysis with modified McCannell sutures in 1 and optical pupillo-plasty in the other. One case required a combined approach to surgerybecause of epithelial ingrowth resulting from antecedent penetrating trau-ma, with a subluxed cataractous lens and glaucoma. In the last case, adense fibrous membrane had grown completely across the pupillary spaceafter Nd:YAG cyclophotocoagulation in a boy with juvenile rheumatoid

654


TABLE VIII: VITREORETINAL SURGERY PERFORMED AT TIME OF


CASE# AGE DX SURGERY VA IOP PRE/ COMPLICS/OTHER(YR) PRE/POST POST (F/U) /OTHER (F/U)

1 2 75 hx of OAG, removal of 20/200cat/IOL, vitreous, 20/160secondary lysis ofangle closre, adhesions tovit to wound wound

2 3 67 epithelial vitrectomy, 20/150ingrowth iridectomy HM

removal ofepith ingrth,fluid-gasexchange,cryotherapy

3 5 80 glaucoma, removal of LPcat surg residual lens 1/200complicated material, vitby expulsive incarc inchor heme wound

4 9 77 CRVO, lensectomy, HMcataract, PRP HMNVI, NVG

5 12 31 old BB lensectomy, HMinjury, repair of iris CFrecent rupt dialysisglobe withpostcapsular lensrapture

6 14 80 epithelial partial irid- 20/150ingrowth ectomy, re- LPafter cat moval ofcomplicated epithelialby loss of ingrowth,nucleus cryotherapy

7 15 15 JRA, uveitis, excision of LPaphakia, fibrous 20/400dense pupillarypupillary membranemembraneafter YAGcyclophoto

8 17 84 ocular reposition 4/200ischemic and suture 20/50syndrome, IOL, PRPNVG,decenteredIOL

2617 (2m)

63 recurrence of5 (6m) epith

ingrowthtreated

4317 (48m)

3020 (12 m)

4942 (6 m)

2521 (25 m)

3221 (13 m)

only eye

3818 (16 m)

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TABLE VIII: (CONTINUED)

CASE# AGE DX SURGERY VA IOP PRE/ COMPICS(YR) PRE/POST POST (F/U) /OTHnER

9 21 45 cong glauc, scleral 1/200 22 (beforecat/IOL, buckle, 20/80 RD)choroidals removal of 6 (15 m)after trabec epi- andw/5FU, total retroretinalRD w/PVR membranes,

fluid-gasexchange,laser toretinal breaks,C3F8 injectn

10 25 34 ROP, high repair of inf 5/200 45myopia, inf RD 20/400 10 (45 m)RD, NVI

11 26 74 cat/IOL, vit biopsy, LP 45recurrent removal of NLP* 4* (8 m)endophthal IOL, intravitx3 (3 diff- antibioticserent organ-isms cul-tured: bact/fungal)

12 31 73 PDR, NVG, PRP HM 46aphakia 20/400 13 (18 m)

13 45 53 penetrating lensectomy, HM 35trauma, epith removal of 20/200 19 (25 m)ingrowth, epithelialirradiation, cyst,cataract cryotherapy

14 59 39 ankylosing pupilloplasty HM 25spondylitis, HM 1 (46 m)chronicuveitis,aphakia,miosis

15 64 71 Chandler's op #2: 20/400 40syndrome, epiretinal HM 6 (85 m)cat/IOL, membraneepiretinal peeling w/membrane TKP, PK,

and IOLexchange

°IOP in 30s@7m, so hadtrabec w/SFU,w/subsequentchoroidalhemorrhageand RD

fluctuatingIOP in botheyes due touveitis, butVA stable andno evidence ofphthisis evenwhen IOP lowtreated x2

656


arthritis, reducing visual acuity to light perception, with persistent IOPelevation.

In these complicated eyes requiring additional vitreoretinal proce-dures at the time of ciliary body photocoagulation, 11 of 15 eyes (73%) hadsuccessful IOP control long-term (12 of 15, or 80%, if the stable eye withIOP 1 mmHg is included), with visual acuity improved or maintained in 11of 14 (73%)

Penetrating Keratoplasty Performed at the Same Time asEndocyclophotocoagulationIn 11 eyes, corneal clouding coexisted with uncontrollable IOP, andendolaser to the ciliary body was performed at the time of penetrating ker-atoplasty. In 5 of these cases a temporary keratoprosthesis was installed topermit vitrectomy and visualization of the ciliary processes. In 6 eyes, theclouded cornea, after epithelial debridement, was clear enough to allowciliary process visualization. In 10 of 11 (91%) of these cases, the IOP wascontrolled at last follow-up. The remaining case with poor visual potentialand a failed PK had diode cyclophotocoagulation that resulted in a pres-sure of 28 mmHg. Seven of 11 grafts (64%) remained clear. One whichfailed was regrafted, for a total of 8 of 11 (73%) clear at last follow-up. Asingle rejection episode occurred. Visual acuity improved significantly in 5eyes, remained stable in 4, and decreased in 2.

Endocyclophotocoagulation as a First Glaucoma OperationIn general, endocyclophotocoagulation is reserved for eyes that have failedconventional glaucoma surgery. In 23 eyes in this series, however, this pro-cedure was considered the primary glaucoma operation of choice. Thesecases are described in greater detail in Table X.

In 12 eyes, the IOP elevation was complicated by other pathologyrequiring a vitreoretinal approach (6 cases with neovascular glaucoma, 2with epithelial ingrowth, 3 with retained nucleus, and 1 with endoph-thalmitis). In 10 eyes a penetrating keratoplasty had been performedalready or was performed at the time of surgery. In one aphakic eye, exten-sive conjunctival scarring precluded a filtering procedure. Successful IOPcontrol was achieved in 16 of these 23 eyes (70%), or 17 of 23 eyes (74%)if a stable eye off glaucoma medications with IOP 22 mmHg is included.Two eyes with epithelial ingrowth failed (1 IOP 5 mmHg, 148 mmHg), asdid an eye with recurrent endophthalmitis, an eye with progressive dia-betic proliferative disease, an eye with hypotony (2 mmHg), and an eyewith no follow-up for 43 months and loss of light perception .

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TABLE IX: CASES WITHOUT PRIOR GLAUCOMA OPERATION

CASE # AGE DIAGNOSIS VA PREE IOP PRE/ ADD'L SURG/(YR) POST POsf (F/U) COMMENTS

1 1 59 trauma,aphakia

2 3 67 epithelialingrowth

LPNLP20/150HM

3 5 80 glauc, cataract LPcomplicated by 1/200loss of nuclearmaterial andexpulsivehemorrhage

4 9 77 CRVO,NVI HMNVG, cataract HM

5 10 68 trauma, CFcataract, ABK 2/200

6 11 73 cat, AC IOL, HMPBK LP

7 14 ? epithelial 20/150ingrowth, s/p 20/400cat w/lostnucleus, vitx,AC IOL

8 17 84 ocular 4/200ischemic 20/50syndrome,NVG, s/pcat/IOL

9 22 68 Pk x3, corneal HMulcers x2 HM

10 26 74 s/p cat/IOL LPrecurrent NLPendophthalm x3(3 different orgscultured, includefungal)

11 30 '66 s/p cat, PK for 20/60ABK 6/200

12 31 73 PDR, NVI, HMNVG, aphakic 20/400

13 33 71 s/p cat, PKx2 20/400for ABK 4/200

45 conjunctival50 (43 mo) scarring63 removal of5 (6 mo) epithelial

ingrowth,fluid-gasexchange,cryotherapy

43 removal of lens17 (48 mo) material at time

of endolaser

3020 (12 mo)2419 (6 mo)

528 (24 mo)

lensectomy,PRPTKP, suturedsecondary PCIOL, PK w/endolaserendolaser x2

25 removal of48 (11 mo) epithelial

ingrowth,fluid-gasexchange,cryotherapy

38 resutured IOL,18 (16 mo) PRP

4717 (15 mo)454° (8 mo)

4310 (11 mo)4613 (18 mo)372 (27 mo)

*after trabecw/5-FUcomplicated bychoroidals andRD

PRP

658


TABLE IX: (CONTINUED)

CASE # AGE DIAGNOSIS VA PRE/ lOP PRE/ ADD'L SURG/(YR) POST POST (FlU) COMMENTS

14 34 77 s/p cat, end- 6/200ophthamitis, PK HMx2 for PBK

15 36 75 glaucoma, s/p HMcat/AC IOL, s/p 3/200PK for PBK

16 43 79 s/p cat/IOL, PK HMx2forPBK HM

17 45 53 penetrating HMtrauma, epith 20/200ingrowth,radiation

18 48 75 s/p cat, PK forABK

-19 53 55 s/p cataract,secondary ACIOL, infectiouskeratitis, PBK

20 55 73 trauma, aphakia

21 66 64 CRVO, NVI,NVG, cataract

22 68 67 PDR, NVI,NVG, cataract

23 70 71 PDR, PC IOL,s/p vitrectomyx3, vitreoushemorrhage,NVG

3011 (9 mo)

40 TKP, IOL XC,19 (12 mo) PK

4613 (13 mo)3519 (25 mo)

3212 (12 mo)2321 (7 mo)

3213 (17 mo)5822 (27 mo)5516 (14 mo)445 (6 mo)

20/30020/4001/20020/100

20/30020/100HMHMHM20/50LPNLP

removal ofepithelialingrowth,lensectomy,fluid-gasexchange,cryotherapy

PK, IOL XC,sutured PC IOL

20/50 beforemacular holelensectomy, PRP

lensectomy, PRP

enucleation forpain

DISCUSSION

This study has two aims: (1) histopathologic characterization of the effectsof transvitreal endocyclophotocoagulation, and (2) evaluation of the clini-cal efficacy and safety of the surgical technique in a large series of patientswith long-term follow-up.

In a rabbit model, endocyclophotocoagulation results acutely in loss ofthe ciliary processes with ablation, proteinaceous exudate, vascular con-gestion, hemorrhage, and stromal edema. Cellular detail is lost with pig-ment dispersion and nuclear pyknosis. Ultrastructurally, subcellular

659

Haller

organelles degenerate with cystoid intracellular spaces and loss of plas-malemma. Chronic changes in animal and human eyes enucleated monthsto years after laser treatment show ciliary body destruction, replacementby scar tissue, and fibrocellular membrane formation. Pigment aggrega-tion is prominent. Abrupt transitions between treated and nontreatedareas are seen, with sparing of adjacent structures. The striking success ofphotocoagulation in ablating ciliary tissue accurately and focally with spar-ing of contiguous structures suggests that the technique could reduce cil-iary body function selectively, without interfering with other eye functions.

Data from the clinical arm of this study support this hypothesis andexpand on the conclusions of two previous smaller series suggesting thattransvitreal endocyclophotocoagulation is useful in the treatment ofrefractory glaucoma.56 Despite the complexity of the ocular pathology inpatients studied (a mean of 3.5 previous operations and 1.3 previous glau-coma operations), successful lowering of IOP (>5 and <22 mmHg) wasachieved in 81% of eyes at 6 months, 87.3% at 12 months, and 68% over-all at last follow-up. Seventy-seven percent of eyes were considered clini-cally stable at last follow-up with adequate IOP control after endolaser tothe ciliary body. Thirty-six patients were able to stop all glaucoma medica-tions, and 75% of those taking carbonic anhydrase inhibitors preopera-tively were able to discontinue them postoperatively.

Visual acuity postoperatively was the same as the preoperative level in30 of 73 eyes (41%), better in 23 eyes (32%), and worse in 20 eyes (27%).In 15 of the 20 eyes with visual loss, acuity dropped owing to comealclouding (8 eyes), progression of underlying disease (4 eyes), or complica-tions from subsequent operations other than endolaser to the ciliary body(3 eyes). Visual loss was attributable to inadequate IOP control in 5 cases.

Complications of hypotony, fibrin reaction, peripheral choroidal effu-sion, choroidal hemorrhage, and/or phthisis occurred in 9 of 73 eyes(12%), 1 of which was enucleated. The fibrin reactions and peripheralchoroidal detachments all resolved without incident (in 1 case adjunctivetissue plasminogen activator was used to aid clearance of the fibrin). Eyeswith penetrating keratoplasty experienced graft rejection in 4 of 35 cases(11 %) and ultimate graft failure occurred in 11 of 35 grafts (31%).

These results compare favorably with reports in the literature of alter-native methods of pressure control in eyes with refractory glaucoma. Inparticular, endocyclophotocoagulation appears to give comparable pres-sure-lowering rates with a reduced frequency of serious complications.

Cyclocryotherapy is credited with control of IOP in about 64% to 87%of cases, depending on type of glaucoma, definition of success, and lengthof follow-up, but is complicated by worsening of vision in 47% to 88%343537

660


and phthisis in up to 12% or more, again depending mostly on the under-lying diagnosis.

Transscleral photocoagulation of the ciliary body is another alternativefor refractory glaucoma, and the largest reported body of data is on Nd:YAG cyclophotocoagulation.3'32'46-80 Successful IOP control is reported in49% to 71% of cases after Nd:YAG treatment. Visual loss is reported in45% or more. Significant postoperative inflammation and pain are report-ed in up to 100% of cases. Phthisis may develop in 11% or more.Sympathetic ophthalmia has also been reported, estimated as occurring in5.8% of cases after Nd:YAG cyclodestruction in one series.74,7880

Focused ultrasound has been reported to lower IOP successfully in asignificant number of patients with uncontrollable glaucoma who havefailed conventional therapy. A multicenter trial reported successful pres-sure lowering after 1 treatment in 48.7% of eyes at 6 months and 38.1% at1 year. In the subset of eyes undergoing retreatment, 83.9% had accept-able IOP at 6 months and 79.3% at 1 year.99 In a separate three-centerstudy, success varied between 66% and 72% of patients, depending on fol-low-up, with complications in 11.4%, including phthisis in 0.6%, hypotonyin 2.5%, and visual loss in 43.4%.58 Twenty percent of eyes reported bySilverman and coworkers99 developed decrease in visual acuity. A majordrawback to focused ultrasound is the equipment and technical expertiseit requires, which has confined its use to a few referral centers.

A small series of eyes with neovascular glaucoma reported by Uram98showed good response of IOP after treatment with endoscopic laser to theciliary processes. Nine of 10 eyes achieved IOP of less than 21 mmHg, 2with hypotony but none with phthisis. The procedure appears promisingin eyes where media preclude visualization of the ciliary processes. Otheroptions to reduce IOP in these eyes with poor acuity include noninvasivetransscleral procedures. If the eye is to be visually rehabilitated withremoval of axial opacities (corneal transplant, cataract extraction, pupillarymembrane removal), endoscopic viewing would appear to have littleadvantage over transvitreal endocyclophotocoagulation.

A widely used alternative to ciioablative surgery in eyes with refrac-tory glaucoma is implantation of a drainage device. Multiple reports on theclinical results achieved (primarily with the use of Molteno, Krupin, andBaerveldt devices, and the Schocket anterior shunt to encircling buckleprocedure) describe successful IOP lowering in 47% to 100% of cases,depending on glaucoma diagnosis, length of follow-up, and definition ofsuccess.27994158 Success rates in the 65% to 78% range are most typical.Complications are reported in 24% to 100% of cases and are similar withall types of drainage devices currently used. Choroidal effusions occur in

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Haller

about 10% to 15%'4"l42and choroidal hemorrhage in 7 to 10%. Numerouscomplications unique to the use of an anterior chamber implant connect-ed to a posteriorly implanted reservoir include tube touch to cornea, iris,vitreous, lens and/or IOL, tube/plate erosion, globe perforation at installa-tion of the device, motility restrictions, initial excessive outflow with shal-lowing of the anterior chamber and/or choroidal effusion, and sterileendophthalmitis. In some eyes with extensive scarring, the dissectionneeded in order to install a drainage device may be difficult."40,'4'

EYES WITH GLAUCOMA POSTKERATOPLASTY

Results of endocyclophotocoagulation in eyes with penetrating keratoplas-ty demonstrate excellent pressure control (91% with IOP between 5 and22 mmHg at 6 months, 93% at 12 months, and 86% deemed clinically sta-ble at last follow-up). However, corneal graft failure eventually developedin 11 of 35 eyes (31%), and rejection episodes occurred in 4 eyes (11%),with an average follow-up of over 28 months. Other than graft failure, theonly complications that occurred in the PK group were 1 case of transientperipheral choroidal effusion and 1 eye with IOP 4 and a clear graft (2 of35 eyes, or 6%).

Cyclocryotherapy was the treatment of choice for medicallyintractable postkeratoplasty pressure elevation for many years. West andassociates3' reported control of IOP after PK in 86% of eyes withcyclocryotherapy, although 2 eyes (14%) became phthisical. Binder andcolleagues3" reported final IOP less than 22 mmHg in all 36 patients sotreated, with complications in 33% (dense secondary vitreous membranein 6 eyes, vitreous hemorrhage in 2, graft failure in 2, phthisis in 1, andmacular edema in 1). Brindley and Shields37 reported a subset of 13 postk-eratoplasty eyes treated with cyclocryotherapy within their series. Allachieved pressure control. In their series as a whole, 68% of eyes lostvision and 12% became phthisical. Cyclocryotherapy has the disadvantageof including not only the ciliary body but also adjacent structures in theeye wall freeze, including corneal endothelium and trabecular meshwork.

Success with IOP lowering after Molteno implantation in eyes afterpenetrating keratoplasty has been reviewed by a number of investigators.McDonnell and coworkers'39 followed 17 eyes. With a mean follow-up of13 months, 12 of 17 eyes (71%) had IOPs less than 21 mmHg after a sin-gle Molteno implant. Repeated surgery increased the successes to 14 cases(82%). Corneal allograft rejection occurred in 7 eyes (41%) after Moltenoplacement. Including 3 regrafted eyes, 13 of 17 grafts were clear at last fol-low-up. Postoperative visual acuities were the same as or better than pre-operative in 12 of 17 eyes (71%). Three eyes developed choroidal detach-

662


ments after Molteno placement, 1 of which remained chronically hypoto-nous .

Kirkness'5 reported a small series of 11 eyes with Molteno implanta-tion after keratoplasty. Seven of 11 grafts (64%) remained clear, 3 (27%)rejected, and 4 (36%) failed. Ten of 11 eyes had adequate IOP control.

Sherwood and coinvestigators'48 reviewed 26 eyes that underwent PKbefore, during, or after Molteno or Schocket drainage procedures. Withmean follow-up of 22 months, 96% achieved final IOP of less than 18mmHg (preoperative IOP was <25 mmHg in 9, <20 mmHg in 5). Graftfailure occurred in 11 of 26 (42%). Eight eyes were regrafted, so the finalclear PK group numbered 21 (81%). Visual acuity remained stable orimproved in 70%. Complications other than PK-related occurred in 6(23%) of the 26 eyes, including choroidal hemorrhage in 2 cases, fibrinreaction in 2 cases, tube occlusion in 1 case, and kissing choroidal effusionsin 1 case.

Beebe and colleaguesl54 reviewed 35 keratoplasty patients who hadbeen treated for elevated IOP with either a Molteno implant (25 eyes) ora Schocket-type anterior chamber tube to encircling band (10 eyes). Thecorneal surgery was performed before the glaucoma procedure in 14 eyes,during the glaucoma procedure in 6 eyes, and after in 15 eyes. Follow-upwas 25 months for the keratoplasty graft and 25 months for the drainagedevice. At final evaluation, 30 of 35 eyes (86%) were judged successfulfrom the IOP standpoint (IOP <22 mmHg with disc and visual field stabi-lization and no further glaucoma surgery). The Schocket procedure hadbeen used in 4 of the 5 eyes that failed. Complications other than graft fail-ure included tube/comeal touch, tube obstruction, tube erosion, malig-nant glaucoma, hypotony, phthisis, and retinal detachment. Graft rejectionoccurred in 12 (34%) of 35 eyes and was progressive in 9 eyes.Nonimmunologic failure was seen in 9 of 35 eyes (26%). Ten eyes wereregrafted, so that at final analysis 25 (71%) of 35 grafts were clear.

Threlkeld and Shields54 evaluated the efficacy of noncontact Nd:YAGtransscleral cyclophotocoagulation for glaucoma after penetrating kerato-plasty in 39 eyes. Follow-up ranged from 3 to 63 months (mean, 27months). Thirty-one of 39 patients (77%) had a final IOP between 7 and21 mmHg. Visual acuity was stable or improved in 44%, but 56% demon-strated visual loss. Of 25 clear grafts at the time of laser cyclophotocoagu-lation, 11 (44%) had later graft decompensation. Other complicationsincluded uveitis in 17%, sustained hypotony in 12%, epithelial defect in12%, loss of light perception in 9%, severe pain in 6%, and phthisis,hyphema, hypopyon, intractable pain, and descemetocele, each in 1 eye(3%).

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Elevated IOP occurs after PK in a significant percentage of eyes.102160-163 Indeed, glaucoma has been called "the single most serious complicationaccompanying keratoplasty."''14 A number of different techniques havebeen reported that provide good pressure control in these complicatedeyes in a high percentage of cases, including cyclocryotherapy, implanta-tion of a drainage device, transscleral Nd:YAG cyclophotocoagulation, andnow transvitreal endocyclophotocoagulation. Comparisons of the seriesare imprecise because of the variations in patient population, follow-up,time of PK and glaucoma procedures (some before, some during, someafter), and methods of reporting data. Endocyclophotocoagulation appearsto be at least as successful in achieving pressure control as any other pro-cedures. It appears to be accompanied by the fewest complications. Ratesof comeal graft failure do not appear to be significantly different in any ofthe groups and are high overall. This is probably the result of a number offactors. Any surgical invasion of the eye after penetrating keratoplasty isdetrimental to graft survival. Corneal grafts have been reported to cloudafter additional surgery in 16% of patients at 2 years by Stark andMaumenee'60 (following ICCE), 20% by Lemp and coworkers'66 (afterICCE), and 25% by Binder'67 following cataract extraction or secondaryIOL placement. The eyes in most series are complicated, with numeroussuperimposed disease processes and multiple repeated grafts. Eyes in theseries reported here had an average of 2.14 grafts each. These eyes are athigh risk for graft failure even without glaucoma or further surgery.Prospective evaluation of different pressure-controlling modalities in arandomized fashion would give the most objective answer to the questionof which glaucoma procedure to use in eyes with uncontrolled IOP afterkeratoplasty.

RESULTS BY GLAUCOMA TYPE

Subgroup analysis of results by glaucoma diagnosis was performed, butnumbers in subcategories were too small to achieve statistical significance.Eyes with secondary angle closure were among the most successful,including in their number most of the eyes with penetrating keratoplasty.The diagnosis of trauma-induced angle changes also carried a good prog-nosis. Eyes with juvenile glaucoma had successful IOP control in almostall cases for many months to years, but then needed other procedures in 4of 9 cases. The endolaser procedure worked well long-term in 5 eyes, but4 eyes ultimately had tube drainage devices installed (3 Krupin and 1Molteno, at 79, 82, 95, and 98 months after initial surgery). No complica-tions were attributed to the endolaser procedures, but 1 eye lost vision fol-lowing post-Krupin choroidal hemorrhage. It seems reasonable to con-

664


elude that the endolaser procedure, if it works, is a safe treatment optionin these eyes. If it fails, the treating surgeon can then resort to other, pos-sibly more risky procedures.

Eyes in this series with neovascular glaucoma did well when comparedwith other series. This may be because combining aggressive retinal pho-tocoagulation with endolaser to the ciliary body at the time of surgery con-trolled the underlying neovascular process, but the numbers are too smallfor definite conclusions to be made. Some results were dramatic: In case68, a one-eyed woman with no previous surgery presented with a blind(hand motions), painful (IOP, 50 mmHg) eye, cataract, florid rubeosis, andangle closure. After 1 operation, combining lensectomy, panretinal photo-coagulation, and endolaser to the ciliary body, she recovered to a stable20/50 visual acuity with IOP of 15 mmHg off medications. Eyes with visu-al potential, even with severe underlying pathology, may be the ideal can-didates for this procedure.

Other categories, including combined mechanism glaucoma, uveitic,chronic narrow angle, epithelial ingrowth, and chronic open angle, hadvery small numbers. Certain cases are worthy of mention for points theyillustrate, however. Case 15 was a one-eyed 15-year-old boy with juvenilerheumatoid arthritis who had undergone 8 previous operations, 6 ofwhichwere glaucoma procedures including cyclocryotherapy three times andtransscleral Nd:YAG once. Following the Nd:YAG treatment his visiondropped to light perception because of a dense reactive pupillary mem-brane, and IOP remained uncontrolled at 32 mmHg. He was put in aschool for the blind. After pars plana vitrectomy with sharp dissection andexcision of the tough pupillary membrane and endolaser to the ciliaryprocesses, pressure dropped to 17 to 21 mmHg, vision improved to20/400, and he returned to his local public school. In uveitic eyes, trans-vitreal endocyclophotocoagulation may be less likely to cause exacerbationof inflammation than a transscleral approach.

Case 73 was a one-eyed diabetic woman with chronic open-angle glau-coma. During attempted phacoemulsification combined with trabeculec-tomy, posterior capsule rupture occurred with loss of the lens nucleus.Postoperatively, her pressure rose to 25 mmHg with inflammation, and thebleb flattened. Surgery combined vitrectomy with removal of lens frag-ments and vitreous incarcerated in the wound, endolaser to the ciliaryprocesses, and IOL placement on remaining peripheral capsule. Hervision recovered to 20/60+ with an IOP of 15 mmHg off medications. Inthis case the primary objective of surgery was removal of the lens nucleusand incarcerated vitreous. It was already clear, however, that this only eyewould have further pressure problems and that the trabeculectomy was

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Haller

already failing. Endocyclophotocoagulation added little to the risk or com-plexity of the surgical procedure and probably saved the eye an additionaloperation. Vitreoretinal surgeons need to be aware of this technique anddevelop a facility with it, in order to add it to their surgical armamentari-um.RE-TREATMENT

Sixteen eyes underwent re-treatment after initial endocyclophotocoagula-tion produced insufficient lowering of IOP. Of these 16 eyes, 13 had fur-ther endolaser, and 3 eyes (all with juvenile glaucoma) had 3 treatmentseach. The 3 eyes that did not have further endolaser all had poor visualpotential and were managed with cyclocryotherapy (2 cases) or tra-beculectomy with 5-fluorouracil (1 case which lost light perception afterchoroidal hemorrhage and retinal detachment posttrabeculectomy). Re-treatment was successful in controlling pressure in 7 (54%) of 13 eyes. Theother 6 ultimately underwent placement of a drainage device (4 eyes), tra-beculectomy with mitomycin C (1 eye), or had no further surgery (1 eye).Re-treatment appears to add significantly to surgical success.

ENDOCYCLOPHOTOCOAGULATION COMBINES WITH OTHER SURGERYIn 31 instances, substantive additional surgery was combined withendolaser to the ciliary body. In 15 cases, vitreoretinal procedures wereperformed (Table VIII), and in 11 penetrating keratoplasty (Table X); bothwere performed in 1 case. Other procedures included lensectomy, repairof iris dialysis, and removal of residual anterior lens material. The tech-nique of endocyclophotocoagulation allows the surgeon to fulfill multiplesurgical objectives in a straightforward and uncomplicated way in eyeswith varied pathology. The glaucoma problem can be approached at thesame time as retinal and/or anterior segment disease, without risking sur-gical success or undue complications.

DISADVANTAGES OF TRANSVITREAL ENDOCYCLOPHOTOCOAGULATIONPrevious discussions reviewing transvitreal endolaser to the ciliary bodyhave emphasized the disadvantage that it requires clear media.97'm In fact,this was rarely a limiting problem in our experience. We were able toexcise pupillary membranes with intraocular knives and scissors, removeresidual lens material with ultrasonic fragmentation and/or vitrectomyequipment, open miotic pupils with iris retractors, and replace opaquecorneas with temporary keratoprostheses and then clear grafts. If an eye isjudged too damaged to warrant an extensive procedure, however, mediaopacities become a relative contraindication to surgery and a less invasiveprocedure, such as transscleral laser or cryotherapy, may be considered.

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TABLE X: PENETRATING KERATOPLASTY PERFORMED AT THE SAME TIME AS


CASE# AGE DX SURGERY VA PRE/ IOP PRE/ COMPICS

(YR) POST POST /OTHER

10 68 trauma, TKP, sutured CFcataract, ABK IOL, PK 2/200

19 77 COAG, TKP, PK CFaphakic, PK HM(ABK)

29 34 Reiger's PK CFsyndrome, 20/250congenitalbreaks in Bruch'smembrane PK

35 69 angle closure PK HMglaucoma, HMaphakic(ABK)

36 75 glaucoma, cat TKP, PK, IOL HMw/AC IOL, exchange 3/200PK (PBK)

44 65 angle-closure TKP, PK HMglaucoma, cat, HMPBK

52 49 penetrating PKtrauma,cataract,PK (cornealscar), ulcer

53 55 aphakia,secondary ACIOL, infectiouskeratitis, PBK

60 71 cataract,endoph-thalmitis,PBK

HM

24 19 PK clear

35 clear20 (9 m)

327 (6 m)

6417 (12 mo)

rej@2 mo

clear

40 graft failed@19 (12 mo) 12 mo

19 diode28 (7 mo) cyclophotocoa-

gulation@5mo, PKfailed

35 clear20/25 10 (12 mo)

1/200 2320/100 21 (7 mo)

PK

PK LPHM

64 71 familial #2 TKP, ERM 20/400Chandler's peel, IOL XC HMsyndrome, PKcat/IOL, PKx4

67 31 keratoconus, PK, removal HMperforated of IOL HMulcer, PK x3cat/IOL

clear

75 clear (repeat9 (13 mo) PK)Repeat PKwith dissectionof epiciliarymembrane @10 mo postop40 endolaser x26 (85 mo) Repeat PK 9

mo after last

3410 (6 mo)

op, OK clrclear

667

Haller

The principal drawback to transvitreal endophotocoagulation of theciliary processes is that it requires vitreoretinal surgical expertise. Thismeans that a team approach to the patient with complicated glaucomamust be pursued. Frequently, the patient is followed by a glaucoma spe-cialist, a uveitis specialist, a pediatric specialist, an anterior segment spe-cialist, and/or a comprehensive ophthalmologist. Unless these physicianshave the knowledge and means to collaborate with a vitreoretinal surgeon,this approach is not an option. Close contact between subspecialty practi-tioners and a coordinated follow-up plan must be developed in order forthese patients with difficult and multifactorial disease processes to receiveoptimum care.

Transvitreal endocyclophotocoagulation has the tremendous advan-tage over all other cilioablative procedures of allowing direct visualizationof the target tissue during treatment, thus permitting precise placement ofa localized focal burn. Ferry"1 pointed out the inaccuracy of transscleralcryotherapy in his 1977 paper with pathologic examination of 12 eyes: in 5of the 12 eyes, destruction was confined to the pars plana with sparing ofthe pars plicata entirely. Appreciation of this pitfall has produced morecareful localizing techniques, but Ferry and coworkers'69 reported in 1995that examination of eyes treated with Nd:YAG cyclophotocoagulationshows that although lesions are in general well placed, areas of iris disrup-tion, iridodialyses interpreted as inadvertent laser iridotomies, and parsplana treatment are found.

The ability to visualize the ciliary processes intraoperatively is perhapsmost useful in endolaser re-treatment or treatment after other ciliary abla-tive procedures have been performed. With blind transscleral re-treat-ment there is no way to judge adequacy of prior ablation, skip areas, orprobe placement inaccuracies. With a transvitreal approach, the coronaciliaris can be examined, inadequately treated areas re-treated, and undis-turbed processes freshly lasered.

The favorable success rates and relative lack of complications report-ed herein may be in part a reflection of the specificity and accuracy oftreatment afforded by this technique. A total of 6 of 73 eyes (8.2%) devel-oped long-term hypotony (3 of which were stable anatomically and visual-ly with clear corneas or grafts) or phthisis. In contrast to a large full-thick-ness eye wall treatment with associated tissue destruction, breakdown ofthe blood-ocular barrier, and inflammation, transvitreal endocyclophoto-coagulation allows a focal (albeit intense) treatment directly to the targettissue.

Transvitreal endocyclophotocoagulation is a valuable addition to thepanoply of options for patients with glaucoma. It has a high rate of long-

668


term success that compares favorably with other surgical alternatives anda relatively low rate of complications in experienced hands. It may be theprocedure of choice when other intraocular problems require surgery con-currently. Further trials are needed to define its optimum clinical role.

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48. Peyman GA, Conway MD, Raichand M, et al. Histopathologic studies on transscleralArgon-Krypton photocoagulation with an exolaser probe. Ophthalmic Surg 1984;15:496-501.

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acterize this cilioablative procedure in an animal model, examine its

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