Early Visual, Refractive, and Astigmatism Vector Outcomes of StreamLight Trans-PRK for High Astigmatism (≥ 2.00 D)

Area of Science:

• Ophthalmology
• Refractive Surgery
• Corneal Surgery

Background:

• High astigmatism presents challenges for refractive surgery.
• Transepithelial photorefractive keratectomy (Trans-PRK) is an evolving technique for corneal correction.
• Assessing outcomes in high astigmatism is crucial for surgical planning.

Purpose of the Study:

• To evaluate early refractive, visual, and astigmatic-vector outcomes of StreamLight™ Trans-PRK.
• To assess the efficacy and safety of this technique in eyes with high astigmatism (≥ 2.00 D).
• To analyze the stability of outcomes in a sub-group of patients.

Main Methods:

• A single-centre cohort study included 171 eyes of 107 patients.
• StreamLight™ Trans-PRK was performed on the WaveLight EX500 platform.
• Astigmatic outcomes were analyzed using the Alpins method; a stability sub-analysis was conducted.

Main Results:

• Mean preoperative cylinder was 3.29 D; mean spherical equivalent (SE) was -2.73 D.
• At one month, mean UDVA was 0.05 logMAR, residual cylinder 0.65 D, and SE -0.22 D.
• 71.3% of eyes achieved SE within ±0.50 D; 53.2% had cylinder ≤ 0.50 D. Efficacy and safety indices were favorable, with no loss of CDVA lines. Vector analysis showed high axis precision (99% within ±15°).

Conclusions:

• Single-step StreamLight™ Trans-PRK provides favorable early visual, refractive, and astigmatic vector outcomes for high astigmatism.
• The procedure demonstrates high axis precision and favorable vector-analytic parameters.
• Outcomes appear stable in the early postoperative period.