Impact of a displaced corneal apex on small incision lenticule extraction

Session Details

Session Title: LASIK and Imaging

Session Date/Time: Tuesday 10/10/2017 | 14:00-15:20

Paper Time: 14:00

Venue: Room 4.1

First Author: : G.Steinwender AUSTRIA

Co Author(s): :    M. Shajari   W. Mayer   D. Kook   N. Ardjomand   T. Kohnen   A. Wedrich     

Abstract Details

Purpose:

To evaluate the possible impact of a displaced corneal apex (point of maximum curvature) on visual results and videokeratographic parameters after small incision lenticule extraction (SMILE).

Setting:

Department of Ophthalmology, Medical University of Graz, Graz, Austria

Methods:

Eyes with previous uncomplicated SMILE for myopia correction were classified in 2 groups upon their preoperative corneal apex location: distance between corneal apex and corneal vertex (point at intersection of patient`s line of fixation and corneal surface) more than 1 mm (Group 1) or equal or smaller 1 mm (Group 2). Visual outcome parameters included uncorrected (UDVA) and corrected distance visual acuity (CDVA), manifest refractive spherical equivalent (MRSE), and refractive astigmatism (RA) 3 month postoperatively. Scheimpflug-derived videokeratographic outcome parameters included mean keratometry value (K-value), root-mean-square higher order aberrations (RMS HOA), and Fourier analysis maximum decentration and irregularity index.

Results:

The study comprised 94 eyes of 48 patients, 44 eyes in Group 1, and 50 eyes in Group 2. All surgeries were performed during early learning curve of two surgeons. Pre- and postoperative RMS HOA were significantly higher in Group 1 than in Group 2 (p=0.002 and p=0.008 [95% confidence interval], respectively). Postoperative CDVA was significantly better in Group 2 (p=0.014). There were no statistically significant differences in postoperative UDVA, MRSE, RA, mean K-value, maximum decentration, and irregularity index.

Conclusions:

In the early learning curve of SMILE surgery, a displaced corneal apex may lead to mild impairment of visual results.

Financial Disclosure:

NONE