Bowman's topography-guided excimer laser ablation using photorefractive keratectomy in mild irregular corneas: a contralateral eye study

Session Details

Session Title: Moderated Poster Session: Trends in Refractive Surgery

Venue: Poster Village: Pod 1

First Author: : E.Torres-Netto SWITZERLAND

Co Author(s): :    A. Saad   D. Gatinel                    

Abstract Details

Purpose:

The epithelium affects the topographical properties of the cornea. This may be relevant not only for preoperative evaluations, but also for surgical planning. This prospective study evaluated and compared the topographic and refractive outcomes of photorefractive keratectomy (PRK) topography-guided either by the epithelium or the Bowman's layer.

Setting:

The study was conducted by the Fondation Ophtalmologique Adolphe de Rothschild, Paris, France

Methods:

Fifty-eight eyes with mild irregular preoperative topography underwent topography-guided PRK. Randomly, one of the patient's eyes had the ablation profile customized from the epithelium, while the contralateral from the Bowman's layer, ie after epithelium removal. Axial corneal keratometry (in the 3rd and 5th central millimeter rings), potential automated corneal visual acuity (logMAR), refractive errors (spherical, cylindrical and axis) and corneal high-order aberrations (total RMS, coma, trefoil and spherical aberration) were analyzed. Two-way multivariate analysis of variation was used to calculate differences between the groups pre- and 3 months post-operatively (CI 95%).

Results:

The mean age of the patients was 30.10 ± 5.11 (ranging from 20 to 40 years old). From the twenty-nine patients, 20 patients were female (68.97%) and 9 were male (31.03%). Preoperatively, there was no significant difference between the two treatment groups (p=0.156). As expected, significant differences were found between the variables before and after surgeries (p=0.000). However, Wilks' Lambda test did not show significant effect between pre- and post-operative parameters based on the treatment groups (p=0.992), that is topography guided by the epithelium or the Bowman's layer.

Conclusions:

To our best knowledge, this is the first clinical demonstration of Bowman's topography-guided excimer laser ablation. The topographic and refractive outcomes of Bowman's topography-guided PRK in mild irregular corneas appear to be comparable to those traditionally customized from the corneal epithelium.

Financial Disclosure:

None