Comparison of contrast sensitivity loss between intrastromal femtosecond laser INTRACOR and LASIK procedure

Session Details

Session Title: Corneal and Scleral Treatment

Session Date/Time: Wednesday 09/09/2015 | 08:00-09:30

Paper Time: 08:24

Venue: Room 13

First Author: : E.Mai TAIWAN

Co Author(s): :    D. Chang                    

Abstract Details

Purpose:

To compare the loss of contrast sensitivity CS function after INTRACOR to conventional LASIK procedures.

Setting:

Far Eastern Memorial Hospital, Taiwan, Dr. Elsa L.C. Mai Nobel eye clinic, Taiwan,Dr. Chao Kai Chang

Methods:

Inclusion criteria for Intracor were 8 presbyopia patients with less than +1.0 diopter of hyperopia. Conventional LASIK procedures include 40 myopic and hyperopic treatments. Evaluation parameters included Pre/post op data for UCVA near/far, BCVA near/far, Topography, Wavescan aberrometer, pupilometer, pachymeter, Contrast Sensitivity evaluation was done with CSV-1000E Vector Vision with/without glare stimulus, pre/post surgical data on 1 week, 1 months and 3 months taken. Compare of contrast sensitivity threshold drop in 4 spatial frequency (3, 6, 12 ,18 cpd) between LASIK and INTRACOR was done, Statistic calculation using Wilcoxon Signed Ranks Test and Student T test.

Results:

Comparing pre and post op Contrast sensitivity threshold data after INTRACOR, CS threshold show significant drop at both Glare and Non glare condition, the drop was seen in all four spatial frequency(P=0.008 for 12 cpd/non-glared). For LASIK procedures the CS threshold drop was most significant in 12 cpd SF/ glared (P=0.002). Compare between INTRACOR and LASIK post OP data, a more severe drop of CS threshold was noted in 3 cpd (P=0.031 t-test) and 6 cpd Spatial frequency (P=0.047 t-test), this difference has reached statistic significance even in non glare condition.

Conclusions:

INTRACOR procedure can produce a gain of uncorrected near vision for presbyopia patients but also introduce a higher lost of contrast sensitivity plus worsen of vision quality compare to conventional LASIK procedure. Pre-surgical patient selection and inform consent should be given with specific regards to night driving and glare conditions.

Financial Interest:

NONE