Large optical zone transepithelial PRK: refractive and aberration outcomes

Area of Science:

• Ophthalmology
• Refractive Surgery
• Corneal Aberrometry

Background:

• Transepithelial photorefractive keratectomy (TPRK) is a common procedure for myopia correction.
• Optimizing optical zone size in TPRK is crucial for refractive outcomes and visual quality.
• Previous studies have explored various optical zone dimensions, but large and extra-large zones require further investigation.

Purpose of the Study:

• To evaluate refractive results and corneal higher-order aberration (HOA) changes after TPRK using large optical zones.
• To compare outcomes between large optical zone (LOZ) and extra-large optical zone (XLOZ) groups.

Main Methods:

• Retrospective review of 222 eyes from 112 myopic patients undergoing single-step TPRK with Smart Pulse Technology.
• Eyes were categorized into LOZ (6.6-7.0 mm) and XLOZ (7.1-7.5 mm) groups.
• Refractive accuracy, safety, efficacy, and corneal wavefront aberrations were assessed at 6-month follow-up.

Main Results:

• High refractive accuracy was achieved: 81.1% within ±0.50 D and 98.2% within ±1.00 D of target refraction.
• Safety and efficacy were comparable between LOZ and XLOZ groups, with no significant haze.
• The XLOZ group showed smaller increases in corneal HOAs, including a slight reduction in coma, compared to the LOZ group (p < 0.05).

Conclusions:

• TPRK with large optical zones provides excellent refractive predictability, safety, and efficacy.
• Extra-large optical zones (7.1-7.5 mm) are associated with reduced postoperative corneal HOA induction.
• Utilizing larger optical zones in TPRK may be beneficial for maintaining postoperative visual quality.