april consultation #8

728 CONSULTATION SECTION

7. V�amosi P, Cs�ak�anyB,N�emeth J. Intraocular lens exchange in pa-

tients with negative dysphotopsia symptoms. J Cataract Refract

Surg 2010; 36:418–424

- The underlying problem in this case is the fibroticreaction of the capsular bag with traction forces onthe ciliary body and the decentration of the IOL. Thephotic phenomena are more likely induced by theIOL optic rather than by the fibrotic reaction of the cap-sular bag. However, due to the fibrotic shrinkage,centration of the IOL in the capsular bag seems to beimpossible.

I would liberate the IOL with an OVD as much aspossible and try to free the haptics from the fibroticcapsule. Where viscodissection is not possible, cutsin the anterior capsule may help. The IOL can beplaced in the sulcus and should center well. Eventhough the haptics are very bulky for the sulcus andmay result in dispersion of iris pigment, this rarely re-sults in a pigmentary glaucoma. The traction forcesdue to the shrinkage of the capsular bag should thenbe released by radial cuts in the anterior capsule.This may also bring the fibrotic area more to the pe-riphery. If during surgery the capsular bag seems tobe too adherent, the IOL and the capsular bag can beremoved and after anterior vitrectomy, an iris-fixatedor scleral-fixated IOL can be implanted. Thus, the pa-tient must be informed that any surgery may resultin loss of capsule support, aphakia, and the need forvitreoretinal surgery.

Katrin Petermeier, MD, FEBOTuebingen, Germany

- This is an interesting case in which a seemingly mi-nor issue is causing real symptoms. Given that theoptic is still well centered, you could be forgiven forpresuming that the patient would be mostly asymp-tomatic. Negative dysphotopsia is a very disturbingphenomenon usually caused by the shadow of theIOL on the peripheral retina, hence the finding of it be-ing inferior, especially when there is a light sourcefrom above. It is also associated with temporal cornealincisions and is seen in the temporal field more com-monly. It is almost exclusively described with IOLsin the capsular bag and not with sulcus or AC IOLs.When patients express these complaints, they shouldnot be dismissed and the surgeon should do his orher best to empathize with the patient and help themunderstand the problem. Telling them the symptomsare quite common after perfect surgery and that theytend to diminish if they refrain from concentratingon the problem may help if you get this message tothe patients in time. If patients have already seen

J CATARACT REFRACT SURG

many colleagues, all of whom have suggested thatthey may be overreacting, this gentle approach wouldnormally fail. This situation calls for a surgicalsolution.

The surgical solution will depend on what isdeemed to be causing the problem. HydrophilicIOLs, especially high-refractive-index acrylic IOLswith square edges, are often to blame. Exchangingthe IOL for a silicone IOL with rounded edges oftensucceeds in these cases.

Alternatively, an attempt could be made to removethe IOL from the bag and relocate it in the sulcuswhile trying to capture the optic in the capsulorhexisopening. Alternatively, a secondary piggyback IOLmay be placed in the sulcus in the eye in front ofthe capsule–IOL diaphragm. This simple and elegantoption not only has a very good chance of reducingor eliminating the negative dysphotopsia but alsopresents an opportunity to correct the small residualrefractive error. Another cause of dysphotopsia is theincreased space between iris and IOL; hence,a McCannel-type suture placed through the inferiorhaptics could reduce the negative dysphotopsia if itmoves the IOL forward, closer to the iris and pupil,and if it pulls the IOL slightly inferiorly. This wouldserve to position the IOL correctly to eliminate thedysphotopsia and, one hopes, would also stabilizethe IOL in this position.

The situation described here suggests that the cap-sular bag–zonular complex would not do well withmanipulation of the IOL. Thus, my first choice wouldbe placement of a sulcus-fixated piggyback IOL, whichcould simultaneously address the residual refractiveerror.

Arthur Cummings, MDDublin, Ireland

Dr. Cumming is a paid consultant to Alcon and Wavelight.

- These “Mickey Mouse” IOLs are surgically easy toimplant; however, when the capsulorhexis is toosmall, capsule contraction syndrome might develop.If the capsulorhexis is too large, the entire IOL or partsof it might dislocate in front of the anterior capsuleleaf.1,2

Brimonidine eyedrops are useful in young patientswith large mesopic or scotopic pupils. However,they should not have a significant effect on the pupilsize of a 71-year-old patient because the scotopic pupilof these patients is usually between 3.5 mm and4.5 mm.3

The optical problem in this patient is caused by theexposed inferior square-edged optic rim that is theresult of the fibrotic retraction of the capsulorhexis

- VOL 38, APRIL 2012