Comparative Outcomes Of Single-Step Transepithelial Photorefractive Keratectomy And Traditional Photorefractive Keratectomy In The Correction Of Myopic Astigmatism

To compare the clinical outcomes of single-step transepithelial photorefractive keratectomy (tPRK) to standard photorefractive keratectomy (PRK) in the correction of myopic astigmatism.

Department of Ophthalmology, Ankara University School of Medicine, Ankara, Turkey.

Consecutive myopic astigmatism patients who underwent single-step tPRK with StreamLight protocol (Alcon Inc., USA) or PRK with mechanical epithelial debridement using WaveLight EX500 excimer laser (Alcon Inc., USA) were included in this observational case-series. Uncorrected (UDVA) and corrected distance visual acuities (CDVA), manifest refraction, contrast sensitivity functions, corneal topographic and aberrometric findings were evaluated at baseline and postoperative 1 month. Postoperative pain and photophobia were assessed by patient-reported 0-10 scores.

Ten eyes of 5 patients with the median age of 29.5±6.7 years (range: 39-21 years) were treated with tPRK and 10 eyes of 5 patients with the mean age of 34.2±8.5 years (range: 44-21) were treated with PRK. Postoperative pain and photophobia scores and duration of pain did not differ significantly between the two groups. At postoperative 1 month, UDVA was 20/20 in 90% of eyes in tPRK and 80% in PRK groups, whereas the mean spherical equivalent refraction was -0.18±0.31 D and -0.35±0.38 D, respectively. Postoperative mesopic contrast sensitivities were measured as 0.30±0.0 logCS and 0.25±0.09 logCS without glare, 0.26±0.05 logCS and 0.23±0.07 logCS with glare in eyes treated with tPRK or PRK, respectively (p>0.05).

In our pilot case-series, single-step tPRK with the new StreamLight platform was found to be effective in the treatment of myopic astigmatism. Visual, refractive, topographic and aberrometric outcomes were comparable to standard PRK, with slightly higher mesopic contrast sensitivity. Studies with more number of patients are required to determine the efficacy of this new tPRK platform.