Corneal graft survival and intraocular pressure control after Descemet stripping automated endothelial keratoplasty in eyes with pre-existing glaucoma.

Corneal graft survival and intraocular pressure control after Descemet stripping automated endothelial keratoplasty in eyes with pre-existing glaucomaDesmond QUEK1, Tina WONG1,2, Donald TAN1,2, Jodhbir MEHTA1,2,3

1Singapore National Eye Centre and Singapore Eye Research Institute2Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore3Clinical Sciences, Duke-NUS Graduate Medical School

The authors have no financial interest in the subject matter of this e-poster

BackgroundDSAEK now the procedure of choice for endothelial dysfunction1-3Reports on effect of DSAEK on IOP control and graft failure in eyes with pre-existing glaucoma limitedIncidence of post-DSAEK IOP elevation 45%4Graft failure rates higher in eyes with prior glaucoma filtration surgery or tube shunts5AimTo describe the effect of DSAEK on IOP control and corneal graft survival in Asian eyes with pre-existing glaucoma or ocular hypertension1. Koenig SB, Covert DJ. Early results of small-incision Descemet stripping and automated endothelial keratoplasty. Ophthalmology 2007;114(2):221-6.2. Price MO, Price FW. Descemet stripping endothelial keratoplasty. Curr Opin Ophthalmol 2007;18(4):290-4. Bahar I, Kaiserman I, McAllum P, Slomovic A, Rootman D. Comparison of posterior lamellar keratoplasty techniques to penetrating keratoplasty. Ophthalmology 2008;115(9):1525-33. Vajaranant TS, Price MO, Price FW, Gao W, Wilensky JT, Edward DP. Visual acuity and intraocular pressure after Descemet stripping endothelial keratoplasty in eyes with and without preexisting glaucoma. Ophthalmology 2009;116(9):1644-50. Letko E, Price DA, Lindoso EM, Price MO, Price FW, Jr. Secondary Graft Failure and Repeat Endothelial Keratoplasty after Descemet Stripping Automated Endothelial Keratoplasty. Ophthalmology 2010 Sep 22 [Epub ahead of print].

MethodsRetrospective case seriesInclusion criteriaConsecutive eyes with pre-existing glaucoma or OHT undergoing DSAEKMinimum follow-up duration of 12 monthsDSAEKBy 5 surgeonsStandard surgical techniqueDonor graft inserted via taco-folded or Sheets glide insertion techniquePost-op prednisolone forte 1% q3H gradual taperMain outcome measuresGraft failuresAdditional IOP lowering treatment post DSAEK

Variables examinedDemographicsDuration of f/uDSAEK indicationsGlaucoma diagnosesDuration of glaucomaPre-DSAEKVAIOPGlaucoma treatmentAdditional intra-op proceduresPhacoemulsificationSynechiolysisACIOL exchangeVitrectomyPost-DSAEKVAMean post-op IOPChange in mean IOPIOP range

Pre-DSAEK visual acuity6/60 or worse6/12 or better32168.12.1Pre-DSAEK IOP (mmHg)13.9 4.3Additional intraoperative procedures1634.0

Indications for DSAEKPBK with PCIOLPBK with ACIOLBK post LPIPBK with previous LPIFailed PKFuchs endothelial dystrophyPosterior polymorphous dystrophyBK post glaucoma filtration surgery1141131151123.48.523.46.423.410.62.12.1

ResultsValue%Number of eyes, patients47, 46Age at DSAEK (mean SD)66.6 9.4Gender (male), Race (Chinese)24, 4151.1, 87.2Duration of follow-up, months27.3 8.5

ResultsValue%Pre-existing glaucoma diagnosesAcute primary angle closurePrimary angle closurePrimary angle closure suspectPrimary angle closure glaucomaPrimary open angle glaucomaSecondary angle closure glaucomaSecondary open angle glaucomaOcular hypertensionAngle closureSecondary glaucoma24573618224244.38.510.614.96.412.838.34.351.151.1Duration of glaucoma diagnosis (months)75.4 69.3

IOP lowering interventions pre-DSAEKLPI pre-DSAEKOn at least 1 topical IOP medicationNo. of topical IOP medications Glaucoma filtration surgery pre-DSAEKTrabeculectomyTrabeculectomy with 5-FUTrabeculectomy with MMCGlaucoma drainage deviceTrabeculectomy + GDD17280.94 0.96145161136.259.6

29.8

Post DSAEK VA and IOP

ResultsValue%Post DSAEK visual acuityChange in VA (Snellen lines)Improvement 2 Snellen linesImprovement < 2 Snellen linesDeprovement 2 Snellen linesVA of 6/12 or better at last follow-upCompared to pre DSAEK5.4 3.73611024

76.623.4051.1p

Graft failures

ResultsValue%Number of DSAEK graft failuresNumber of repeat DSAEKNumber of second DSAEK graft failuresInterval to graft failure (months)83112.8 7.01737.533.3

Graft failure reasonsEndothelial rejectionSubsequent intra-ocular proceduresRepositioning of IOLTrabeculectomy complicated by gross hyphaemaCentral graft-host dislocationCytomegalovirus endothelitis42

11

Control groupNo. of eyes undergoing DSAEK in the same time frame, by same surgeons, without pre-existing glaucomaNo. of graft failuresCompared to eyes with glaucoma137

11

8p=0.08

Kaplan-Meier curve for graft survivalKM estimated probability of graft survival at1 year = 100%2 years = 94.2%

Risk factors for graft failureNone identified

IOP treatment post DSAEKRisk factors for need for additional IOP lowering treatmentNo pre DSAEK glaucoma filtration surgeryOdds ratio = 10.8, p = 0.002 (univariate)Additional intra-operative procedures during DSAEKOdds ratio = 18.2, p = 0.008 (univariate)Odds ratio = 12.2, p = 0.033 (multivariate)

ResultsValue%On at least 1 topical medication post DSAEKCompared to pre DSAEKRequiring fewer topical medications post DSAEKRequiring additional IOP lowering treatmentRequiring additional topical medication(s) onlyRequiring glaucoma filtration surgery onlyRequiring additional medication(s) and surgeryInterval from DSAEK and glaucoma surgery (months)No. of topical medications post DSAEKNo. of additional topical medications post DSAEK36

32921269.3 6.92.0 1.51.1 1.474.5p=0.056.461.772.46.920.7

p

DiscussionEyes that had undergone glaucoma surgery pre-DSAEK were less likely to require additional IOP lowering treatment post-DSAEKSuggests that pre-DSAEK glaucoma filtration surgery is able to adequately control post-DSAEK IOP elevations in majority of eyesEyes that underwent additional intraoperative procedures during DSAEK were more likely to require additional IOP-lowering therapy post-DSAEKAdditional procedures presumably incited additional post-operative inflammation, or caused further direct damage to the trabecular meshwork, leading to post-DSAEK IOP riseMonitoring of glaucoma progression remains a challenge in eyes with corneal decompensation secondary to endothelial dysfunctionPerimetry results pre-DSAEK are seldom reliable nor accurateOptic disc is often not clearly visualizedAngle assessment hindered by peripheral corneal opacificationIn our study, mean highest IOPs of 27.4 8.9 and a wide range of IOP fluctuation of 18.2 9.6 mm Hg were observed post-DSAEKHowever, the mean rise in IOP post-DSAEK was modest, with an overall mean increase of 2 mm HgPrompt and efficient lowering of raised IOP post-DSAEK could explain for the overall low rise in IOPEfforts should be made to reduce raised IOP in post-DSAEK glaucomatous eyes, to prevent progression of glaucomatous optic nerve damage

LIMITATIONS

Retrospective Small sample sizeLack of control groupNon-standardization of glaucoma treatment protocolsFurther prospective randomized controlled studies will be required to better elucidate True effect on intraocular pressure controlGlaucoma progression

CONCLUSIONS

With prompt and appropriate intervention, IOP in glaucomatous eyes undergoing DSAEK can be controlled with minimal increase post-DSAEKGlaucomatous eyes without prior filtration surgery and eyes that underwent additional intraoperative procedures during DSAEK are more likely to require additional IOP-lowering therapyThese eyes should be carefully monitored, and IOP-lowering therapy promptly instituted to prevent possible progression of glaucoma