Topoguided Prk Versus Corneal Wavefront-Guided Prk In Eyes With Irregular Corneas: A Comparative Prospective Study

Published 2026 - 44th Congress of the ESCRS

Reference: POCOR319 | Type: Free paper | DOI: 10.82333/pxdq-hj42

Authors: Dr Khalid Alburayk* ¹ , Prof. Dr Abdulrahman Almuammar ²

¹Ophthalmology ,King Saud University Medical City,Riyadh,Saudi Arabia, ²Ophthalmology ,¹Research Excellence Center in Ophthalmology and Visual Sciences, Department of Ophthalmology, College of Medicine, King Saud University,Riyadh,Saudi Arabia;Ophthalmology ,²King Saud University Medical City,riyadh,Saudi Arabia

Purpose

To compare the efficacy, safety, and corneal topographic outcomes of topography-guided photorefractive keratectomy (TG-PRK) using the WaveLight Allegretto/EX500 platform with corneal wavefront-guided PRK (CWF-PRK) using the Schwind AMARIS platform in eyes with irregular corneas, including keratoconus, post-LASIK ectasia, and other corneal irregularities.

Setting

Single-center retrospective comparative study conducted at a tertiary corneal refractive surgery unit, Saudi Arabia.

Methods

A total of 22 eyes were included: 16 eyes treated with TG-PRK on the WaveLight platform (Group 1) and 16 eyes treated with CWF-PRK on the Schwind AMARIS platform (Group 2). Indications included keratoconus (KC), post-LASIK ectasia,corneal irregularities following penetrating keratoplasty (PKP), and anterior corneal haze. All eyes underwent preoperative and postoperative Pentacam HR corneal tomography. Main outcome measures included maximum keratometry (Kmax), mean keratometry (Kmean), K1, K2, central corneal thickness (CCT), ablation depth, best-corrected visual acuity (BCVA), and subjective refraction. Mitomycin C was used adjunctively in the majority of cases. Combined same-session corneal cross-linking (CXL) was performed where indicated

Results

Baseline mean Kmax was 51.3 ± 7.4 D in Group 1 (WaveLight) and 53.0 ± 7.1 D in Group 2 (Schwind), with comparable preoperative corneal irregularity profiles. Mean age was 39.6 years (Group 1) and 46.0 years (Group 2). Mean central ablation depth was 47.0 µm in Group 1 versus 92.0 µm in Group 2, reflecting the Schwind platform's wavefront-optimized approach targeting higher-order aberrations

At 1-month follow-up, TG-PRK (Group 1) demonstrated a mean Kmax reduction of -3.69 D (n=9 eyes), while CWF-PRK (Group 2) showed a mean Kmax change of -0.64 D (n=10 eyes ), consistent with the predominantly HOA-targeting strategy of the Schwind platform in this cohort. Corneal regularization, was observed in both groups across available follow-up intervals

Conclusions

Both topography-guided PRK using the WaveLight platform and corneal wavefront-guided PRK using the Schwind AMARIS platform appear to offer meaningful corneal regularization in eyes with irregular corneas. TG-PRK demonstrated greater Kmax reduction at early follow-up, while CWF-PRK targeted higher-order aberrations with greater tissue removal. Prospective comparative studies with standardized follow-up protocols and larger sample sizes are warranted to establish the relative superiority of either approach.

Due to the prospective nature of this study and the varying follow-up periods complete dataset was available for a subset of eyes. Ongoing data collection is in progress with prospective enrollment to strengthen the comparative analysis.