Objective monitoring of corneal backward light scattering after femtosecond LASIK

Session Details

Session Title: LASIK I

Session Date/Time: Sunday 06/09/2015 | 08:00-10:00

Paper Time: 09:33

Venue: Room 11

First Author: : G.Savini

Co Author(s): :                        

Abstract Details

Purpose:

To investigate the changes of corneal backward light scattering, as measured by a rotating Scheimpflug camera with automated corneal densitometry software, in eyes treated by femtosecond laser in situ keratomileusis (FS-LASIK).

Setting:

GB Bietti Foundation IRCCS, Rome, Italy

Methods:

The cornea was examined preoperatively and postoperatively at 1 day, 1 week, 1, 3 and 6 months in 23 patients that underwent myopic FS-LASIK. Local analysis of corneal backscatter was performed on four concentric radial zones across 12 mm diameter (0-2 mm, 2-6 mm, 6-10 mm and 10-12 mm) and at a different corneal depth (anterior 120 μm, central, and posterior 60 μm of the cornea).

Results:

A statistically significant increase of corneal backward light scattering (p<0.0001) was detected within the central 10mm of the anterior cornea. This increase in corneal densitometry gradually recovered by 6 months., The difference with respect to the preoperative values was no longer statistically significant at 3 and 6 months after surgery in the central cornea, whereas it remained significant in the midperipheral annulus ranging from 6 to 10mm, where the flap edge is located.

Conclusions:

FS-LASIK is followed by an increase of corneal backward light scattering during the early postoperative period. Whereas the increase of cornea densitometry at the flap edge location is can be related to a scarring reaction, the explanation for such increase in the central anterior cornea remains speculative. Possible mechanisms include residual interface particles and laser-related inflammation, which cannot be detected at the slit-lamp but can be objectively identified by Scheimpflug imaging and specific software.

Financial Interest:

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