Histopathology of epi-LASIK in eyes with virgin corneas and eyes with previously altered corneas
Accepted 3 July 2007.
Purpose
To perform a histological analysis of free epithelial flaps that were intentionally created with an Epi-K epikeratome (Moria S.A.) during epi-LASIK in eyes with virgin corneas and eyes with previous corneal surgery or keratoconus.
Setting
Vissum–Instituto Oftalmológico de Alicante, Alicante, Spain.
Methods
This prospective and consecutive case series comprised 18 free flaps obtained from 18 patients. Twelve patients had virgin corneas, and 6 had altered corneas from previous surgery, trauma, or keratoconus. The flaps were fixed in 4% buffered formaldehyde (pH 7) for posterior histopathological analysis. Serial cuts of each flap were performed, and the sheets were stained with hematoxylin–eosin and periodic acid-Schiff. The main outcome measure was the histopathology of the corneal flaps.
Results
All flaps from virgin corneas consisted entirely of epithelium without residual stromal tissue or Bowman's layer. Histopathological analysis of the flaps after epi-LASIK in patients with previously altered corneas showed varying levels of stroma in all cases.
Conclusion
Epi-LASIK with the Epi-K epikeratome effectively cleaved the epithelium from Bowman's layer in healthy corneas; however, when the integrity of Bowman's layer is compromised, epi-LASIK should be avoided as stromal invasion will likely occur.
From Vissum–Instituto Oftalmológico Alicante (Alió, Rodriguez) and Miguel Hernandez University (Alió), Alicante, and Instituto Universitario de Oftalmobiologia Aplicada (Mendez), Valladolid, Spain; and the Laservision Eye Institute (Kanellopoulos), Athens, Greece
Corresponding author: Jorge L. Alió, MD, PhD, Research and Development Department, Vissum–Instituto Oftalmológico Alicante, Avenida Denia s/n. Edificio Vissum, 03016 Alicante, Spain.
No author has a financial or proprietary interest in any material or method mentioned.
Presented in part at the XXIII Congress of the European Society of Cataract & Refractive Surgeons, Lisbon, Portugal, September 2005.
Supported in part by a grant from the Spanish Ministry of Health, Instituto Carlos III, Red Temática de Investigación en Oftalmología, Subproyecto de Investigación Básica (C03/13), and by Moria S.A., Antony, France.
ABSTRACT