Wavefront-guided PRK for ametropia correction in cross-linked keratoconic eyes

Session Details

Session Title: Keratoconus and Phakic IOLs

Session Date/Time: Monday 12/09/2016 | 16:30-18:30

Paper Time: 17:00

Venue: Hall C4

First Author: : M.Shafik Shaheen EGYPT

Co Author(s): :    A. Shalaby   M. Khalifa                 

Abstract Details

Purpose:

To evaluate the clinical outcomes of wavefront-guided (WFG) photorefractive keratectomy (PRK) using a high definition aberrometer in keratoconic eyes at least 1 year after corneal collagen cross-linking (CXL)

Setting:

Horus Vision Correction Center, Alexandria, Egypt.

Methods:

Prospective interventional case series study including a total of 34 consecutive eyes of 25 patients with keratoconus grade I or II according to the Amsler-Krumeich classification treated with CXL at least one year before the laser treatment. All cases underwent WFG PRK using a high resolution aberrometer for treatment planning. Visual, refractive and ocular aberrometric outcomes were evaluated during a 12-month follow-up. Astigmatic changes were analyzed with the Alpins vector method.

Results:

A significant improvement was observed in uncorrected and corrected distance visual acuity (p<0.001). Mean efficacy and safety indices at 12 months postoperatively were 1.58±1.11 and 1.96±1.52, respectively. Manifest sphere and cylinder were reduced significantly (p<0.001), with 76.5% of eyes having a spherical equivalent within ±1.00 D at 12 months postoperatively. Mean difference vector and magnitude of error were 1.06±0.92 and 0.43±0.86 D, respectively. Some corneal irregularity indices were reduced significantly with surgery (p=0.005) as well as the level of ocular higher order aberrations (HOA), primary coma, and trefoil (p<0.001).

Conclusions:

Sequential WFG PRK using a high resolution aberrometer for treatment planning after CXL is an effective option to correct the spherocylindrical error and to minimize the level of HOAs in mild and moderate keratoconus if the maximum intended ablation depth that does not exceed 15% of minimal corneal thickness

Financial Disclosure:

NONE