Masking fluids in excimer laser phototherapeutic keratectomy: a comparative study

Session Details

Session Title: Surface Photoablation

Session Date/Time: Monday 12/09/2016 | 14:30-16:30

Paper Time: 15:51

Venue: Hall C1

First Author: : M.Tavolato ITALY

Co Author(s): :    A. Catania   A. Fasolo   A. Galan              

Abstract Details

Purpose:

to evaluate the efficacy of different masking fluids using a reproducible model of irregular corneal surface.

Setting:

San Paolo Ophthalmic Center, San Antonio Hospital, Padova, Italy

Methods:

ex-vivo analysis on 12 human corneas. Each cornea was first treated with excimer laser (50 µm ablation) through a metallic grid to create a reproducible model of irregular corneal surface. A phototherapeutic keratectomy (100 µm ablation) was performed using different masking fluids: hydroxypropylmethylcellulose 0.3% with dextran 70 solution 0.1%, carboxymethylcellulose 1%, balanced salt solution (BSS) and sodium hyaluronate 0.25%. Corneal surface was then examined by means of scansion electron microscopy (SEM) and transmission electron microscopy (TEM).

Results:

SEM analysis showed different degrees of corneal surface roughness, saline deposits and collagen structure alteration consequent to excimer laser thermal effect and related to the type of fluid mask used during the treatment. TEM analysis in sodium hyaluronate 0.25% sample showed reduction in excimer laser thermal effect preventing collagen fibrillar aggregation, resulting in higher corneal surface smoothness.

Conclusions:

Fluid masks are useful tool in phototherapeutic keratectomy treatment, protecting corneal surface from thermal damage, also influencing excimer laser ablation rate. Sodium hyaluronate 0.25% showed best fluid mask efficacy, resulting in smooth, regular corneal surfaces.

Financial Disclosure:

... research is funded, fully or partially, by a company producing, developing or supplying the product or procedure presented