Himanshu Matalia, MD

Ashwini Ranganath, MD

N Raghu, MD

Rohit Shetty, MD

Cornea & Refractive Services, Narayana NethralayaSuper Specialty Eye Hospital & Post Graduate Institute of OphthalmologyBangalore - 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 endotheliumAnt. diameter larger (9 mm) placing sutures away from the visual

axis.Technically difficult2

1. Lucio Baratto, Elisabetta Bohm. The use of femtosecond laser in penetrating keratoplasty. Am J Ophthalmol 2007;143:737-742

2. 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

• IntralaseTM (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;143:737-

742

3. 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;145:772-774

4. 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 series22 eyes of 22 consecutive patient (9:13, M:F) with advanced keratoconus

underwent Mushroom-IEK from October 2008-October 2009. Inclusion criteria: Mushroom-IEK with min. follow-up of 6 monthsPrimary 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 BCVAChange in the endothelial count: Preop & postop 6 months (clinical

confocal microscopy)

Methods - Operative Technique

IntraLase FS Laser60-kHz femtosecond laser

Mushroom graft for K’conusPreserves most host endotheliumSutures in periphery→less suture induced astigmatism

Graft size = Host size (no size disparity)Commonly use size:

Anterior diameter: 8.5 mmPosterior diameter: 7 mm

Modified suturing techniqueSutures 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 performAll statistical tests were two-sided and performed at the significance

level of α=0.05.

Results - Visual Acuity

Pre op CF

1st month 20/60

3rd month 20/60 – 20/40

6th month 20/40

Pre op 20/200

1st month 20/40

3rd month 20/40 – 20/30

6th month 20/30

p= 0.001 p= 0.001

• No statistically significant change between postop groups• Preop v/s postop 6 months: p= 0.001

Results - Astigmatism

62.9

46.543.6 45.5

40

45

50

55

60

65

Preop 1 month 3 month 6 month

Keratometry

Avg. K

• 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

8.56

4.783.85 3.22

0

2

4

6

8

10

preop 1 month 3 month 6 month

Keratometric Astigmatism

Astigmatism (± D)

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: 6/9BCVA: ± /-2.5 DC X 70 20/25

ResultsEndothelial density: (on confocal microscope)

Preoperative: 2840 / mm2

Postop 3 months: 2330 / mm2

Postop 6 months: 2225 / mm2

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