Posters

Custom-Q versus wavefront optimized photorefractive keratectomy for myopia with or without astigmatism correction

Poster Details

First Author: J.Simao PORTUGAL

Co Author(s):    I. Osório   E. Neves   M. Raimundo   P. Melo   A. Rosa   J. Murta     

Abstract Details

Purpose:

To compare the results between photorefractive keratectomy (PRK) with Custom-Q or with Wavefront-optimized (WFO) profiles in terms of asphericity and spherical aberrations, 6 months post-operative.

Setting:

Tertiary referral center (Centro Hospitalar e Universitário da Universidade de Coimbra, Coimbra, Portugal).

Methods:

Fifty-three eyes(39 patients) were enrolled on this retrospective case series, including patients with myopia and/or astigmatism, submitted to refractive surgery with PRK (Allegretto WAVE Eye-Q Excimer Laser System, Alcon), in a Custom-Q ablation (34 eyes) or WFO procedure (19 eyes). Inclusion criteria: minimum follow-up of 6 months; age over 21 years; stable refractive error for 2 years; spherical equivalent inferior to 7.5 diopters (D); percentage of altered tissue under 40% and expected final corneal curvature >35 D. Eyes with other ophthalmological pathologies were excluded. Baseline and postoperative asphericity and optical aberrations were evaluated with Pentacam (Oculus Optikgeräte, Wetzlar, Germany).

Results:

The demographic and preoperative refractive data are similar between groups (all p≥0,05). Post-operative spherical equivalent (SE) in the Custom-Q and WFO groups was within 0.50D in 100% and 97.1% of eyes, and within 0.25D in 78.9% and 73.7% of eyes, respectively. Variation of Q-value was 0.6±0.35(range -0.07-1.24) for Custom-Q group, and 0.65±0.4 (range -0.05-1.4) in the WFO group (p=0.61). In a multivariate linear regression model, variation of Q-value was not influenced by the ablation profile (B=0.04,p=0.49,95%CI[-0.08-0.17]). SE was a strong predictor (B=-0.3,p<0.01,95%CI[-0.39-0.21]). There were no significant increases in RMS-total aberrations (p>0.05 for both groups) and no difference between groups (p=0,22).

Conclusions:

In our sample, Custom-Q ablation was not significantly different from Wavefront optimized ablation regarding post-operative asphericity. Both techniques were effective and safe for myopic and/or astigmatic correction up to -5.5D SE, without significant changes in spherical aberration.

Financial Disclosure:

None