Visual Acuity Outcomes After Trans-scleral Cyclophotocoagulation: A Systematic Review and Meta-analysis.

Purpose

To evaluate best-corrected visual acuity (VA) outcomes following trans-scleral cyclophotocoagulation (TSCPC) in patients with refractory glaucoma.

Design

Systematic review and meta-analysis.

Methods

The full protocol was registered on PROSPERO (42023485891). The electronic databases OVID, MEDLINE, and EMBASE were searched using keywords related to TSCPC and visual acuity outcomes (start date to February 7, 2025). Meta-analysis was completed using random effects models and risk ratios to calculate pooled estimates.

Results

In total, 90 studies with 6331 eyes were included. The weighted mean patient age was 61.8 (SD = 9.8) years, and 53.3% of patients were male (n = 3374). Follow-up periods of the studies consisted of 19.8% with less than 1 year follow-up, 38.4% with between 1 and 2 years, and 40.7% with more than 2-year follow-up. Among 19 studies and 1246 eyes, the weighted mean preoperative VA was 1.11 logMAR (SE = 0.02) (20/258 Snellen) and post procedure was 1.12 logMAR (SE = 0.02) (20/264 Snellen). Meta-analysis of 19 studies and 1,246 eyes did not show a statistically significant difference between VA before TSCPC and at last follow-up (mean difference: -0.10 logMAR, 95% CI = -0.22 to 0.01, I 2 = 78.9%, P = .077). In 59 studies and 3,855 eyes, 50.0% (SE = 0.3) of patients maintained their VA at final follow-up, with 6.8% (SE = 0.2) showing a 1-line improvement, 9.0% (SE = 0.2) improving by 2 lines or more, 17.6% (SE = 0.2) decreasing by 1 line, and 16.9% (SE = 0.3) decreasing by 2 lines or more. In 84 studies and 5,941 eyes, the mean preoperative IOP was 34.2 (SE = 0.09) mm Hg, which dropped to 18.3 mm Hg (SE = 0.05), with 79.3% of patients achieving an IOP of less than 22 mm Hg. Meta-analysis of 42 studies and 2393 eyes showed a mean reduction of 1.1 glaucoma medications pre procedure to last follow-up (95% CI = 0.89-1.31, I 2 = 91.76, P < .0001). There was a significant negative linear relationship between total energy (Joules) administered with logMAR best-corrected visual acuity (BCVA) outcome (correlation coefficient = -0.008, I 2 = 77.7%, P = .038). There was no significant correlation between BCVA with duration (milliseconds) of TSCPC application (correlation coefficient: -7.4 × 10 -6 , I 2 = 21.5%, P = .876).

Conclusions

This meta-analysis suggests no significant decrease in VA after TSCPC, with a moderate degree of certainty. Larger amounts of total energy during TSCPC were found to be correlated with worse BCVA. However, given the substantial heterogeneity and observational nature of most studies, these findings should be interpreted with caution.