Objective To perform a systematic review and meta-analysis of the clinical evidence of the treatment effect of surgical cyclodialysis in the management of intraocular (IOP) in patients with glaucoma.

Methods A comprehensive literature review was conducted of peer-reviewed interventional studies from the PubMed, Cochrane, Web of Science and EMBASE databases of surgical cyclodialysis treatment for the lowering of intraocular pressure in patients with glaucoma. Key outcome measures of treatment success were long-term IOP control, as well as IOP-lowering medication burden and the incidence of intraoperative and postoperative adverse events. The meta-analysis was registered with Prospero ID CRD42025632759

Results A total of 40 studies spanning a publication period of more than 100 years of surgical cyclodialysis treatment encompassing data from over 4,082 eyes were included in the analysis. Clinical evidence comprised observational, non-randomized studies, 75% of which involved an ab-externo approach and 25% comprised an ab-interno cyclodialysis intervention. Given the natural evolution of the clinical paradigm over the years, changes in surgical technique, instrumentation and addressable population, the overall analysis was constructed to account for the significant variability in outcomes reporting. Across the final evaluable dataset, the clinical performance of cyclodialysis surgery was characterized by overall qualified success rates of 72.3% on average (range 33%-97%) over a postoperative follow-up period ranging from 6 to 132 months. Depending on surgical technique and disease severity, reported success rates indicate slightly increased efficacy and lower rate of complications with ab-interno intervention. Durability of the cyclodialysis procedure varied significantly, with higher rates of failure in patients with advanced and refractory glaucoma. Specific complications such as persistent hyphema, hypotony and vision loss were reported infrequently. All outcomes, including IOP reduction, ocular safety, and durability, showed significant improvement with the newer interventional ab-interno surgical techniques.

Conclusion Cyclodialysis remains an enduring surgical intervention and one of the few available surgical options for uveoscleral outflow enhancement in glaucoma patients. The IOP lowering effect of the procedure can be significant, albeit variable, with better clinical performance in mild and moderate glaucoma and with advanced interventional ab-interno surgical approaches.

Synopsis Results of a meta-analysis comprising more than 4,000 glaucoma cases of cyclodialysis surgery for the lowering of intraocular pressure demonstrate significant and sustained efficacy of one of the few surgical interventions for uveoscleral outflow enhancement.

The authors have declared no competing interest.

This study did not receive any funding

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.

Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

Yes

I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

Yes

Statements

Ethics Statement This study is a systematic review and meta-analysis of previously published data. No new human or animal subjects were involved.

Funding None.

Conflicts of Interest None declared.

Data Availability All data analyzed in this study are from previously published sources, as cited in the manuscript.

License The authors have not selected a Creative Commons license for this preprint.

Synopsis Results of a meta-analysis comprising more than 4,000 glaucoma cases of cyclodialysis surgery for the lowering of intraocular pressure demonstrate significant and sustained efficacy of one of the few surgical interventions for uveoscleral outflow enhancement.

All data produced in the present study are available upon reasonable request to the authors