Himanshu Matalia, MD Ashwini Ranganath, MD N Raghu, MD Rohit Shetty, MD Cornea & Refractive Services, Narayana Nethralaya Super Specialty Eye Hospital & Post Graduate Institute of Ophthalmology Bangalore - INDIA Authors have no financial interest Poster 605 Early results of mushroom shaped Intralase Enabled Keratoplasty (Mushroom-IEK) for advanced keratoconus

Introduction Traditional penetrating keratoplasty (PKP) for keratoconus : Requires a small size graft to avoid disturbing normal endothelium but the smaller graft has higher risk of suture induced and unpredictable astigmatism leading to prolonged visual rehabilitation time. 1 Mushroom graft − Ideal shape for PKP in keratoconic eyes. Post. diameter smaller (7 mm) taking less endothelium Ant. diameter larger (9 mm) placing sutures away from the visual axis. Technically difficult 2 1. Lucio Baratto, Elisabetta Bohm. The use of femtosecond laser in penetrating keratoplasty. Am J Ophthalmol 2007;143: Busin M, Arffa RC. Microkeratome-assisted mushroom keratoplasty with minimal endothelial replacement. Am J Ophthalmol 2005;140:138 –140

Femtosecon laser enable keratoplasty The advent of femtosecond laser has provided more finite control and precision in corneal surgery with minimal collateral damage. 3,4 Intralase TM (Abbott Medical Optics, Santa Ana, California, USA) has enabled us to dissect cornea with great precision in various shapes like mushroom shape, top hat, zig-zag etc. 1 We present here the largest series of Mushroom-Intralase Enabled Keratoplasty (Mushroom-IEK) 1. Lucio Baratto, Elisabetta Bohm. The use of femtosecond laser in penetrating keratoplasty. Am J Ophthalmol 2007;143: Yong M Por, Jacob Y Chuan Cheng, Anand Parthasarathy, Jodhbir S Mehta, Donald T H Tan. Outcomes of Femtosecond Laser assisted penetrating keratoplasty. Am J Ophthalmol 2008;145: Louis Hoffart, Helene Proust, Frederic Matonti, Bernard Ridings, John Conrath. Short term results of penetrating keratoplasty performed with the Femtec Femtosecond Laser. Am J Ophthalmol 2008;146:50-55

Purpose To evaluate the efficacy of mushroom shaped Intralase Enabled Keratoplasty (Mushroom-IEK) for patients with advanced keratoconus

Methods Prospective, non-randomized interventional case series 22 eyes of 22 consecutive patient (9:13, M:F) with advanced keratoconus underwent Mushroom-IEK from October 2008-October Inclusion criteria: Mushroom-IEK with min. follow-up of 6 months Primary outcome measures: Preop & postop 1, 3, 6 months Uncorrected visual acuity (UCVA) Best corrected visual acuity (BCVA) Keratometry (K): using Pentacam Secondary outcome measures: Time taken to achieve stable BCVA Change in the endothelial count: Preop & postop 6 months (clinical confocal microscopy)

Methods - Operative Technique IntraLase FS Laser 60-kHz femtosecond laser Mushroom graft for K’conus Preserves most host endothelium Sutures in periphery→less suture induced astigmatism Graft size = Host size (no size disparity) Commonly use size: Anterior diameter: 8.5 mm Posterior diameter: 7 mm Modified suturing technique Sutures superficial (up to anterior lamellae only) 8.5 mm 7.5 mm

Methods – statistical test The statistical analysis was carried out using SPSS (SPSS Inc., Chicago, IL, version 15.0 for Windows). All quantitative variables were estimated using measures of central location (mean, median) and measures of dispersion (standard deviation and standard error). Normality of the data was checked For normally distributed data, means of preop and postop (1,3, 6 months) were compared using one-way ANOVA (analysis of variance). For skewed data post hoc tests were perform All statistical tests were two-sided and performed at the significance level of α=0.05.

Results - Visual Acuity Pre opCF 1 st month20/60 3 rd month20/60 – 20/40 6 th month20/40 Pre op20/200 1 st month20/40 3 rd month20/40 – 20/30 6 th month20/30 p= No statistically significant change between postop groups Preop v/s postop 6 months: p= 0.001

Results - Astigmatism Keratometric astigmatism − Measured on Pentacam –Statistically significant change between preop and postop (p=0.001) –No statistically significant change in avg. K & keratometric astigmatism from 1 to 6 months –Suggestive of early topographic stabilization of the cornea

Results - Refractive outcome No statistically significant change in refraction from 1 month to 6 months Suggestive of early visual rehabilitation Correlates to early topographic stabilization by postop 1 month UCVA: CF ½ m BCVA: -6DS/-12DC X 10 20/60 UCVA: 6/9 BCVA: ± /-2.5 DC X 70 20/25

Results Endothelial density: (on confocal microscope) Preoperative: 2840 / mm 2 Postop 3 months: 2330 / mm 2 Postop 6 months: 2225 / mm 2 Complications: One patient had acute endothelial rejection at 3 months postop, successfully treated but developed raised intraocular pressure (IOP controlled on medication) due to steroid response. 18% reduction by first 3 months

Conclusions Early results showed that Mushroom-IEK for advanced keratoconus is, Safe & effective technique Provides early visual rehabilitation & Faster topographic stabilization