Predictors affecting myopic regression in -6.0 to -10.0 D myopia after laser-assisted sub-epithelial keratomileusis and laser in situ keratomileusis flap creation with femtosecond laser-assisted or mechanical microkeratome-assisted

Session Details

Session Title: LASIK I

Session Date/Time: Sunday 23/09/2018 | 14:00-16:00

Paper Time: 14:06

Venue: Room A3, Podium 2

First Author: : Z.Jihong CHINA

Co Author(s): :                        

Abstract Details

Purpose:

To compare the predictive factors of postoperative myopic regression among subjects who have undergone laser-assisted subepithelial keratomileusis (LASEK), laser-assisted in situ keratomileusis (LASIK) flap created with a mechanical microkeratome (MM) and flap created with a femtosecond laser (FS). All patients recruited had a manifest SE from -6.0 to -10.0D myopia. A predictive model of postoperative myopic regression would be derived from the study that could provide an accurate tool to estimate an individual’s affective factors in laser refractive surgery.

Setting:

Beijing Aier-Intech Eye Hospital, Beijing, China.

Methods:

Retrospective comparative study. The study enrolled 496 eyes in LASEK group, 1054 eyes in FS-LASIK group; and 910 eyes in MM-LASIK group. Refractive outcomes were recorded at1day,1week, 1, 3, 6, and 12 months postoperatively. A Cox proportional hazards model was used to evaluate the impact of the three types of surgeries and other covariates on postoperative myopic regression. Myopic regression was defined as residual myopia < -0.50 D and a > 0.50-D shift toward myopia during the follow-up visits.

Results:

At 12 months, the survival rates were 52.19%, 59.12% and 58.79% in the MM-LASIK, FS-LASIK, and LASEK groups respectively. Risk factors included thicker post-operative central corneal (P≦0.01), older age (P≦0.01), aspherical ablation (RR=1.22, P = 0.02), larger transitional zone (TZ) (RR=1.22, P = 0.03); steeper corneal curvature (P =0.01), thicker preoperative central corneal (P < 0.01), lower preoperative myopia (RR=0.79, P < 0.01), longer duration of myopia and with contact lens (P= 0.02, < 0.01), larger optical zone (OZ) (RR=0.68, P =0.02) were protective factors. The highest probability of postoperative myopic regression was MM-LASIK among the three (P < 0.01).

Conclusions:

MM-LASIK was the highest myopic regression, followed by FS-LSAIK and LASEK. Older age, aspheric ablation used, thicker post-operative central corneal thickness, enlarging transitional zone would contribute myopic regression; steeper postoperative corneal curvature (Kmax), longer duration of myopia, thicker preoperative central corneal thickness, lower manifest refraction SE and enlarging optical zone would prevent postoperative myopic regression in myopia from -6.0D to -10.0D. The model originated from the study was created to predict postoperative myopic regression from -6.0 to -10.0D myopia.

Financial Disclosure:

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