Prophylaxis of postoperative endophthalmitisWe commend the authors of the European Society of

Cataract & Refractive Surgeons’ (ESCRS) study of theprophylaxis of postoperative endophthalmitis aftercataract surgery1,2 for their comprehensive and thor-ough work in addressing this vital topic. The mainfindings of the studydie, that intracameral cefurox-ime has an intrinsic benefit and that intracameralcefuroxime plus postoperative topical levofloxacin isa more effective prophylaxis than either agent in isola-tiondare welcome, if not unexpected. It is thereforebeneficial to administer cefuroxime at the end of pha-coemulsification procedures. What this study does notaddress, however, is how to administer it. Despite thestudy’smaximum antibiotic regimen, cases of endoph-thalmitis were seen. Therefore, we must continue tolook for ways to reduce the incidence.

At our ophthalmic department, patients havingcataract surgery receive 3 drops of topical chloram-phenicol 0.5% preoperatively, povidone–iodine in theconjunctival sac just before surgery, subconjunctivalcefuroxime (125mg)at the endof surgery, anda taperedcourse of combination betamethasone–neomycin eye-drops for 3 weeks postoperatively. At our hospital,in a consecutive series of 5641 eyes from January 1,2000, to December 31, 2005, there was only 1 case(culture negative) of presumed postoperative endoph-thalmitis, which occurred after surgery complicatedby posterior capsule rupture and anterior vitrectomy.This yields an incidence of postoperative endophthal-mitis of 0.018% (zero cases of culture-positive endoph-thalmitis) compared with the incidence of 0.058%(2/3428) in the ESCRS study.

Our experience suggests that cefuroxime may pro-vide more effective prophylaxis when administeredinto the subconjunctival space than when adminis-tered into the anterior chamber. The reason for thisbenefit is not clear. Subconjunctival administrationmay offer better prophylaxis by behaving as a depotpreparation and prolonging the availability of the an-tibiotic via sustained absorption through the ocularcoats. The increased duration of this bacteriolytic envi-ronment would impede the establishment of patho-gens during the crucial early wound-healing period.When subconjunctival administration is combinedwith preoperative and postoperative antibiotics, theeye is further protected during the most vulnerableperiod.

An environment hostile to bacterial survival wouldbe particularly beneficial during the first 24 hourswhile the corneal epithelium is healing.3 Animal stud-ies4 show that antibiotics given subconjunctivally canbe detected in the anterior chamber 24 hours later, sug-gesting that this method would provide the desired

antibacterial cover until the natural barrier functionswere restored.

The ESCRS study shows intracameral antibiotic tobe better than no antibiotic but does not look at differ-ent modes of administration. Our series suggests thatsubconjunctival cefuroxime may be a more effectiveprophylaxis against postoperative endophthalmitis.Intracameral cefuroxime is not a panacea, and thechoice and delivery route of postoperative antibioticconstitute only part of the prevention of postoperativeendophthalmitis. Factors such as careful preoperativeassessment, meticulous preparation and draping ofthe surgical field, and guaranteed sterility of equip-ment are no less important. Further prospective stud-ies are needed to find the most effective route ofadministration and type of antibiotic in the quest tofurther reduce the rate of this serious intraocularsurgery complication.

David M. Spokes, MRCOphthGavin Walters, MRCP, FRCOphth

Harrogate, United Kingdom

REFERENCES1. Seal DV, Barry P, Gettinby G, et al. ESCRS study of prophylaxis

of postoperative endophthalmitis after cataract surgery; case for

a European multicenter study; the ESCRS Endophthalmitis Study

Group. J Cataract Refract Surg 2006; 32:396–406

2. Barry P, Seal DV, Gettinby G, et al. ESCRS study of prophylaxis

of postoperative endophthalmitis after cataract surgery; prelimi-

nary report of principal results from a European multicenter study;

the ESCRS Endophthalmitis Study Group. J Cataract Refract

Surg 2006; 32:407–410

3. Khatib HA, Karseras AG. With regards to ‘‘endophthalmitis’’

(editorial). Eye 2004; 18:555–556; Eye 2006; 20:627

4. Ellis PP, Riegel M. Prolonged aqueous humor levels of subcon-

junctival antibiotics after treatment with acetazolamide and/or

timolol. Ophthalmic Surg 1988; 19:501–505

Q 2007 ASCRS and ESCRS

Published by Elsevier Inc.

LETTERS

REPLY: I congratulate the authors on their low rateof endophthalmitis analyzed retrospectively.

A clinical trial cannot be criticized for failing to an-swer questions it did not ask. It is always tempting, al-though dangerous, to extrapolate from genuine trialresults.

The study showed the overwhelming benefit ofintracameral cefuroxime over intensive perioperativeantibiotics. We have to start somewhere. We considerthat the study results and the Swedish experiencemake intracameral cefuroxime the ideal agent anddelivery system today. If it is superseded in the futureby other drugs or delivery systems so be it, but suchstudies would be extensive, expensive, and probablyfutile.dPeter Barry, FRCS

0886-3350/07/$dsee front matter 561doi:10.1016/j.jcrs.2006.11.022