A Systematic Review of Malyugin Rings in Cataract Surgery: Surgical Outcomes, Efficacy and Safety

Small pupils complicate cataract surgery and increase intraoperative risk. The Malyugin ring is a widely used mechanical pupil-expansion device lacking a comprehensive evidence synthesis. This review evaluated its efficacy and safety in adults.

A total of 4 databases (EMBASE, MEDLINE, CINAHL Plus, Web of Science) were searched from inception to October 21, 2024, with an updated search conducted on June 28, 2025. Randomized and observational studies involving adults undergoing cataract surgery with a Malyugin ring were eligible. The outcomes included dilation adequacy, surgical duration, intraoperative complications, endothelial cell loss, and visual acuity. Risk of bias was assessed using RoB 2 and ROBINS-I, and the certainty of evidence was evaluated using GRADE. A narrative synthesis was performed in accordance with PRISMA guidelines (PROSPERO CRD420251069562).

Altogether 10 studies (3,233 eyes) were included. The Malyugin ring provided stable dilation (5.5–7.0 mm) in small pupils and in patients with pseudoexfoliation syndrome. Relative to iris hooks and manual stretching, it was associated with shorter phacoemulsification time (15.2 vs. 19.8 s) and lower endothelial cell loss (9.35% vs. 13.77%). The visual outcomes were favorable, although some studies reported higher rates of iris tears and pupil ovalization compared with those observed with comparator techniques.

These findings suggest advantages in surgical efficiency and early visual recovery. However, the evidence comprises 2 randomized and 8 non-randomized studies with risk of bias ranging from low to serious, and no outcomes could be pooled; therefore, comparative conclusions remain tentative.

The Malyugin ring appears effective and generally safe in adult cataract surgery; reported complications were typically not visually significant. Certainty of evidence was low to very low (GRADE), and superiority over alternative devices is not established.