(LASIK) surgery by Tekwani and Huang (Am J Ophthal-mol 2002;134:311–316), we commend the authors for awell-researched article. We were interested to note that 24of 247 eyes (9.7%) developed intraoperative epithelialdefects (IED).

We use the Chiron Technolas 217 (Baush and LombSurgicals GmBh, Dornach, Germany) LASIK machinewith a Hansatome microkeratome (Baush and LombSurgicals). All surgeries were performed by experiencedsurgeons. In bilateral cases we routinely perform LASIKsurgery in the right eye followed by the left eye. Pre-operatively, topical 0.5% proparacaine eye drops are in-stilled once or twice a few minutes before the surgery. Forlubrication of the microkeratome, distilled water is usedafter the application of the suction ring and the suction iskept on while doing the reverse pass.

As compared with the authors, in our experiencefrom 1999 to 2002, only 1.3% (27/2,056) of the eyesdeveloped intraoperative epithelial defects. Of these, 10were in the right eye and 17 in the left eye. Thepreponderance of intraepithelial defects in the left eyecould be possibly due to the fact that we use the same bladefor both the eyes of one patient. In view of our experiencewe think that the instillation of topical phenylephrine andtropicamide 30 minutes (contact period) before surgerycould be an important cause for the development of IEDin all three regimen groups. Topical proparacaine inregimen one and two also could be a cause. We do not usemydriatics, as a dilated pupil is not required in ourmachine.

Our patient group was younger (23.7 � 5.39 years vs40.3 � 10.3 years) than the study group. This could also beresponsible for a lower incidence due to better epithelialadhesion in the younger group and thinner corneas devel-oping lesser appositional force against the applanatingsurface of microkeratome.

Use of balanced salt solution for gear track lubricationmay lead to precipitation on the gear track, so theexcursion of the microkeratome on the dovetail may notbe smooth, leading to a corkscrew type of epithelial defect.

Also, we would like to know the fate of patients inwhom the epithelial defect developed; that is, if there wasdevelopment of any epithelial ingrowth, diffuse lamellarkeratitis, and the final uncorrected and best-correctedvisual acuity. Shah and coauthors1 have reported that therisk of diffuse lamellar keratitis was 24 times greater if anyepithelial defect of any size occurred. Moreover, there arereports of development of diffuse lamellar keratitis with useof carboxymethylcellulose 1% before keratotomy2 (in24/30 eyes, 80%).

NAMRATA SHARMA, MD

MAYANK S. PANGTEY, MD

RASIK B. VAJPAYEE, MBBS, MD

New Delhi, India

REFERENCES

1. Shah M, Misra M, Wilhelmus KR, Koch DD. Diffuse lamellarkeratitis associated with epithelial defects after laser in situkeratomileusis. J Cataract Refract Surg 2000;26:1312–318.

2. Samuel MA, Kaufman SC, Ahee JA, Wee C, Bogorad D.Diffuse lamellar keratitis associated with carboxymethycellu-lose sodium 1% after laser in situ keratomileusis. J CataractRefract Surg 2002;28:1409–1411.

AUTHOR REPLY

WE THANK DRS. SHARMA, PANGTEY, AND VAJPAYEE FOR

sharing their experience regarding laser in situ kerato-mileusis (LASIK)-related epithelial defect. We must takecare in comparing our results with that of Dr. Sharma’sgroup because the demographics are very different. Thereis evidence that the risk of intraoperative epithelial defect(IED) is two or three times greater in lighter pigmentedpersons (our patients in Cleveland) compared with moredarkly pigmented persons.1 Even if we ignore the racialdifference, the age difference alone would more thanaccount for the different rates of IED. Using the riskestimation equation (Figure 1) in our article,2 we estimatethat the average patient in Dr. Sharma’s series, who is 24years old, received anesthetic just prior to LASIK (our eyedrop regimen 3), and had suction maintained on thereverse pass of the Hansatome, would have an IED risk ofabout 0.7%, which is even lower than the incidence of1.3% in Dr. Sharma’s series. Therefore, we cannot draw aconclusion regarding another factor (such as mydriatic eyedrops) in our study as causing a higher IED risk comparedwith Dr. Sharma’s series.

We are performing a case-control study on the sequelaeof IED to be published later. In short, complication rateswere low or visual outcomes were good in both groups,with no significant difference between them. The rate ofdiffuse lamellar keratitis in our control LASIK series isbelow 2%, even with the use of carboxymethocellulose andbalanced saline solution as lubricants. Some aspects of mysurgical technique may have reduced the possibility ofcarboxymethocellulose-incited DLK. I only paint a thinlayer of lubricant on the cornea. With reverse-pass suctionon, I generally do not see any fluid on the stromal bed afterreflecting the flap. I also irrigate of the flap interfacevigorously with balanced salt solution for a few secondsafter replacing the flap.

DAVID HUANG, MD, PHD

Cleveland, Ohio

REFERENCES

1. Bashour M. Risk factors for epithelial erosions in laser in situkeratomileusis. J Cataract Refract Surg 2002;28:1780–1788.

2. Tekwani NH, Huang D. Risk factors for intraoperative epi-

AMERICAN JOURNAL OF OPHTHALMOLOGY394 AUGUST 2003

thelial defect in laser in-situ keratomileusis. Am J Ophthalmol2002;134:311–316.

Iridociliary Apposition in Plateau IrisSyndrome Persists After CataractExtraction

EDITOR:

TRAN AND ASSOCIATES (AM J OPHTHALMOL 2003;135:40–

43)1 reported a persistence of the iridociliary appositionand a deepening of the anterior chamber depth aftercataract extraction in patients with plateau iris syndrome.This is a most interesting finding. However, the authorsdid not comment about the changes in the anteriorchamber angle and, specifically, changes in the iridotrabe-cular apposition. This issue would be clinically relevant.For example, if there were a widening of the anteriorchamber angle (despite the persistent iridociliary apposi-tion), perhaps lens extraction might be considered inpatients with complete plateau iris syndrome. Could I askthe authors to address this point and describe the appear-ance of the anterior chamber angle and iridotrabecularrelationship before and after cataract surgery?

AUGUSTO AZUARA-BLANCO, MD, PHD

Aberdeen, Scotland

REFERENCE

1. Tran HV, Liebmann JM, Ritch R. Iridociliary apposition inplateau iris syndrome persists after cataract extraction. Am JOphthalmol 2003;135:40–43.

AUTHOR REPLY

WE APPRECIATE DR. AZUARA-BLANCO’S INTEREST IN OUR

article. There are a few points to be addressed. First, onewould expect deepening of the anterior chamber afterlensectomy because the cataractous lens was replaced by aposterior chamber intraocular lens. Second, all eyes in thestudy had undergone both laser iridotomy and argon laserperipheral iridoplasty (ALPI), which opened the anglessufficiently to avoid lensectomy. After ALPI, the angle isnot necessarily uniformly open, since the greatest openingoccurs adjacent to the laser burns. Some eyes still had areasof appositional closure. Since the appearance of the ante-rior chamber angle can vary from spot to spot, we took fourdifferent locations for our measurements. Figure 1 in thepublished article shows the ultrasound biomicroscopicimage of such an angle before and after cataract extraction.Before surgery, the angle is closed in the section shown,whereas afterward the angle opened slightly to becomeslit-like. These findings were similar in the other eyesreported but not illustrated. Additional figures were culled

at the request of the reviewers when the manuscript wasfirst submitted. We have not performed ultrasound biomi-croscopy on any eye with plateau iris syndrome before andafter cataract extraction after iridotomy without havinghad ALPI, as this makes dilation much safer.

Historically, one of us (R.R.) noted this finding a decadeago, when Dr. Pavlin called to tell me that he hadsuccessfully imaged a live patient. I flew to Toronto thefollowing week with five patients diagnosed clinically withplateau iris syndrome. Previously, documentation of thedouble hump sign as diagnostic of plateau iris, aside fromgonioscopy, had not been possible. These findings werepublished simultaneously.1,2 One patient from the Torontoseries underwent cataract extraction several months later.Surprisingly, the angle remained slit-like and the doublehump sign was still present, indicating that elimination ofsupport by the lens still did not allow the angle to fallopen. This led us to conjecture that the zonules play somerole in maintaining the anterior position of the ciliarybody, although anatomically, they have been reported topass through, but not originate from, the pars plicata. Allof these patients were older, and one could questionwhether younger patients with plateau iris syndrome havethe same anatomic cause. One also wonders what would bethe effect of intracapsular cataract extraction on the anglewidth.

Lensectomy has been advocated as a means of openingthe angle in patients with angle-closure.3 Greve4 felt thatcataract extraction should be considered in primary angle-closure glaucoma instead of a filtering procedure or com-bined cataract and filtration. Gunning and Greve5

advocated cataract extraction over filtration surgery, evenin eyes with good visual acuity. In eyes with plateau irissyndrome, however, we feel that ALPI is sufficientlysuccessful at opening the angle that lens extraction shouldbe based on visual criteria rather than as a means to openthe angle.

ROBERT RITCH, MD

JEFFREY M. LIEBMANN, MD

New York, New YorkH. VIET TRAN, MD

Lausanne, Switzerland

REFERENCES

1. Pavlin CJ, Ritch R, Foster FS. Ultrasound biomicroscopy inplateau iris syndrome. Am J Ophthalmol 1992;113:390–395.

2. Ritch R. Plateau iris is caused by abnormally positioned ciliaryprocesses. J Glaucoma 1992;1:23–26.

3. Teekhasaenee C, Ritch R. Combined phacoemulsificationand goniosynechialysis for uncontrolled chronic angle-closureglaucoma after acute angle-closure glaucoma. Ophthalmology1999;106:669–675.

4. Greve EL. Primary angle closure glaucoma: extracapsularcataract extraction or filtering procedure? Int Ophthalmol1988;12:157–162.

5. Gunning FP, Greve EL. Uncontrolled primary angle closure

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