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Large optical zone transepithelial PRK: refractive and aberration outcomes
Sultan Kaya Ünsal1, Orkun Özkan2
1Department of Ophthalmology, Faculty of Medicine, Uskudar University, Istanbul, Turkey.
Purpose:
To assess refractive outcomes and corneal higher-order aberration changes following transepithelial photorefractive keratectomy (TPRK) performed with large optical zones.
Methods:
Data from 222 eyes of 112 myopic patients undergoing single-step TPRK with Smart Pulse Technology were reviewed retrospectively. Eyes were classified according to programmed optical zone diameter into large optical zone (LOZ, 6.6-7.0 mm; n = 57) and extra-large optical zone (XLOZ, 7.1-7.5 mm; n = 165) groups. Refractive results, safety and efficacy indices, and corneal wavefront aberrations were assessed at the 6-month follow-up.
Results:
Refractive accuracy was high, with 81.1% of eyes within ± 0.50 D and 98.2% within ± 1.00 D of target refraction at 6 months. Safety and efficacy were comparable between the LOZ and XLOZ groups, and no clinically significant haze was observed. Corneal higher-order aberrations increased more in the LOZ group, whereas smaller changes and a slight reduction in coma were observed in the XLOZ group (p < 0.05).
Conclusions:
TPRK performed with large optical zones demonstrated excellent refractive predictability, safety, and efficacy. The use of extra-large optical zones was associated with smaller increases in corneal higher-order aberrations, suggesting that larger optical zones may help preserve postoperative optical quality after TPRK.
