Laser vision correction after radial keratotomy: 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 articles on refractive surgeries in post-RK patients by conducting a search on 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 (PRK), 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 post-RK patients with hyperopia had a significant improvement in UDVA, whereas no such improvement was observed in patients with myopia.

Photorefractive keratectomy in the management of postradial keratotomy hyperopia and astigmatism

Background:

The aim of this study is to evaluate the results of photorefractive keratectomy (PRK) in the management of postoperative hyperopia and astigmatism in patients with history of radial keratotomy (RK).

Materials and Methods:

This prospective nonrandomized noncomparative interventional case series enrolled consecutive eyes treated with PRK after RK. In cases, in which (1) wavefront (WF) scan was undetectable during primary examinations; and/or, (2) WF data were not transferable to the excimer laser device, patients were treated with the tissue-saving (TS) mode. Patients with detectable/transferable WF were assigned to WF-guided advanced personalized treatment (APT).

Results:

Thirty-two and 47 eyes were managed by APT and TS modes, respectively. Pooled analysis of both APT and TS groups showed improvement in uncorrected distant visual acuity and corrected distant visual acuity. The amount of sphere, cylinder, corneal cylinder, spherical equivalent, defocus equivalent, and total aberration showed improvement as well.

Conclusion:

PRK seems to bring favorable outcome and safety profile in the management of post-RK hyperopia and astigmatism. It is crucial for practitioners to warn their patients about the fact that they may still have progressive refractive instability regardless of their choice on the laser method of vision correction.