ESCRS - FP28.04 - Femtosecond Laser-Assisted Pterygium Surgery (Flaps) Using A Customized Novel Algorithm On The Ziemer Z8

Femtosecond Laser-Assisted Pterygium Surgery (Flaps) Using A Customized Novel Algorithm On The Ziemer Z8

Published 2024 - 42nd Congress of the ESCRS

Reference: FP28.04 | Type: Free paper | DOI: 10.82333/w032-h606

Authors: Shayne S Tan* 1 , Yu-Chi Liu 1 , Andri Kartasasmita Riau 2 , Evelina Han 2 , Jodhbir Mehta 1

1Singapore National Eye Centre,Singapore,Singapore;Singapore Eye Research Institute,Singapore,Singapore, 2Singapore Eye Research Institute,Singapore,Singapore

Purpose

We report the first human use of a novel algorithm to produce rectangular customizable CAGs using femtosecond-laser (FSL)-assisted pterygium surgery (FLAPS) to address the abovementioned challenge.

Setting

Pterygium is a common ocular surface disorder. Conjunctival autografts (CAG) have become the gold standard treatment after pterygium resection, and CAGs that are thinner without Tenon tissue have shown superior results. However, this is difficult to achieve consistently with manual dissection.

Methods

We first tested this novel algorithm in 4 pig eyes to show the reproducibility of the dissected CAGs. We then treated 6 pterygia of 5 patients using this novel algorithm with FLAPS. After manual resection and removal of the pterygium, trapezoid CAGs of a pre-set 7mm x 10mm dimensions were then dissected with the Ziemer Z8 laser set at a 60μm depth with a set dissection time of 28s, using 100% energy for the horizontal conjunctival stromal lamellar cut and 130% for the side cuts, and then glued onto the resected defect.

Results

For the pig eyes, the average CAG length and width were 9.8 ± 0.1mm and 7.3 ± 0.04mm, respectively. The average deviation of porcine CAG was 7% ± 3% for length, and 8% ± 4% for width. The average patient was 56.8 ± 7.3 (SE) years old. The programmed CAG area was 219.9mm2 and the achieved area was 224.3 ± 2.5mm2, with a minimal deviation of 2% ± 1%. The eventual CAG thickness was 58.7 ± 2.2 μm, with a minimal deviation of 7% ± 2%. The average time taken to remove the FSL-prepared CAG to unfold it onto the cornea was 20.5 ± 6.1 seconds. At post-operative week (POW) 6 follow-up, no post-operative complications or recurrences occurred, and the conjunctival epithelium at the donor CAG site had completely healed by POW1 without scarring.

Conclusions

This novel algorithm using the Z8 FSL in FLAPS provides consistent and accurate customizable trapezoid ultrathin CAGs, which were then glued onto the resection defects without any complications. Longer follow-up and larger cohorts will need to be studied for recurrence and complication rates.