Laser Vision Correction after Radial Keratotomy: A Systematic Review and Meta-analysis.

Laser vision correction for residual refractive errors in patients with previous radial keratotomy (RK) presents a challenging task. Different techniques have been used with varying outcomes. This study aimed to systematically review published manuscripts on refractive surgeries in post-RK patients search in PubMed, Scopus, and Web of Science. The final analysis included 35 studies that described a total of 888 eyes. Our systematic review and meta-analysis demonstrated a significant improvement in uncorrected distance visual acuity (UDVA) for photorefractive keratectomy, topography-guided-PRK, wavefront-guided-PRK, and femtosecond- laser-assisted in situ keratomileusis (LASIK), while mechanical microkeratome LASIK did not yield such significant improvements. Moreover, our results suggest that hyperopic post-RK patients had a significant improvement in UDVA, whereas no such improvement was observed in myopic patients.