Interpreting corneal changes after PRK: Integrating biomechanics with tomographic remodeling

Photorefractive keratectomy (PRK) alters corneal biomechanical and tomographic measurements, but postoperative change, an abnormal index classification, and progressive ectasia are distinct. Saif et al. reported biomechanical changes at 6 months; a separate Pentacam cohort showed tomographic changes at 1 month. Clinically and topographically normal eyes assessed approximately 25 years after PRK also had frequent abnormal classifications. These different cohorts and observation periods cannot establish a common postoperative trajectory or show that an abnormal result is benign in an individual eye. Prospective paired Pentacam and Corvis ST measurements in the same eyes, followed by independent validation, are needed to develop postoperative references. Until then, serial clinical and tomographic findings should inform interpretation of isolated index abnormalities.