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Topography-guided transepithelial photorefractive keratectomy to correct irregular refractive errors after radial
Mohammad Ghoreishi1, Alireza Peyman1, Nima Koosha1
1From the Department of Ophthalmology (Ghoreishi, Peyman, Koosha, Golabchi, Pourazizi), Isfahan University of Medical Sciences and the Department of Research and Development (Ghoreishi), Parsian Clinic of Ophthalmology, Isfahan, Iran.
Purpose:
To evaluate the efficacy and safety of topography-guided transepithelial photorefractive keratectomy (PRK) in a group of patients with post-radial keratotomy (RK) showing irregular corneas.
Setting:
Feiz University Hospital, Isfahan, Iran.
Design:
Prospective case series.
Methods:
Consecutive patients who had irregular astigmatism after RK with stable refraction and topography for at least 1 year were recruited. All eyes had excimer laser topography-guided single-step transepithelial PRK. The efficacy, safety, predictability, and corneal wavefront aberration changes were assessed 6 months after the surgery. Vector analysis was performed using the Alpins method to evaluate the astigmatic treatment.
Results:
Twenty-two patients (22 eyes) were enrolled. The patients' ages ranged from 37 to 61 years (45.77 years ± 4.9 [SD]); there were 12 men (54.54%) and 10 women (45.46%). Uncorrected distance visual acuity significantly improved after 6 months of treatment (0.45 ± 0.19 logarithm of the minimum angle of resolution [logMAR] preoperatively and 0.25 ± 0.19 logMAR after 6 months) (P < .001). Moreover, the corrected distance visual acuity significantly improved at the end of the study (0.14 ± 0.13 logMAR preoperatively and 0.09 ± 0.11 logMAR after 6 months) (P = .01). Furthermore, the aberrometric values were significantly reduced at the 6-month visit (P < .001). The mean of the surgically induced astigmatism was 2.15 ± 1.44 diopters. No significant complication was observed.
Conclusion:
Topography-guided single-step transepithelial PRK is a safe and effective method for treating the irregular refractive errors in post-RK patients.
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