Photorefractive keratectomy results in myopic patients with thin cornea eyes.

Abstract

BACKGROUND:

To evaluate the results of visual acuity and quality, and corneal integrity in myopic patients with a thin cornea who received photorefractive keratectomy (PRK).

MATERIALS AND METHODS:

In this before-after interventional study, 30 myopic eyes with a myopia -3.76 ± 1.72 (-6.50 to -1.25) D and a corneal thickness of 486.03 ± 11.93 (452-499) μm at the thinnest point received PRK. In myopia was more than 4D, mitomycin C was used with PRK. The surgery was performed with an excimer laser (VISX STAR, Abbott Medical Optics, Abbott Park, US).

RESULTS:

The safety and the efficacy index of the surgery was 1.01 ± 0.05 and 1.00 ± 0.05 in these patients, respectively. All the patients were within ±0.5D of emmetropia 1 year after the surgery. Mesopic contrast sensitivity (CS) had a significant increase in two spatial frequencies of six (P = 0.003) and 12 (P = 0.003). Total coma (P < 0.001), spherical aberration (P < 0.001), and total higher-order aberrations (HOA) (P < 0.001) also showed a significant increase. Corneal hysteresis (P < 0.001) and corneal resistance factor (P < 0.001) showed a significant decrease after 1 year.

CONCLUSION:

PRK is a safe, effective, and predictable procedure with desirable effects on mesopic CS in patients with corneal thickness <500 μm, which increases HOAs and decreases corneal integrity proportionate to its value before the procedure.

• Authors: Hassan Hashemi, Mohammad Miraftab, Soheila Asgari
• Journal: Oman journal of ophthalmology (Oman J Ophthalmol) 2015 Jan-Apr Vol. 8 Issue 1 Pg. 24-7 ISSN: 0974-620X [Print] India
• PMID: 25709270 (Publication Type: Journal Article)