Primary angle closure and primary angle closure glaucoma in retinal vein occlusion.

Purpose: To investigate the frequency of primary angle closure (PAC) and primary angle closure glaucoma (PACG) in patients with retinal vein occlusion (RVO) based on a hospital population.

Methods: A total of 375 consecutive cases newly diagnosed with RVO by fluorescein fundus angiography at a single eye centre in Peking were reviewed. Gonioscopy was performed in all patients. Glaucoma was diagnosed according to the criteria of the International Society of Geographical and Epidemiological Ophthalmology. Retinal vein occlusion was classified as central retinal vein occlusion (CRVO), hemicentral retinal vein occlusion (HRVO), or branch retinal vein occlusion (BRVO), and as arteriovenous crossing RVO (AV-RVO), optic cup RVO (OC-RVO), optic nerve RVO without optical nerve head swelling (NONHS-RVO), or RVO with optical nerve head swelling (ONHS-RVO) based on the site of venous occlusion. Percentage of PAC or PACG for each type of RVO were calculated.

Results: PACG had a frequency of 4.1% [95% confidence interval (CI) 2.2-6.9%] in 317 RVO patients [5.3% (95% CI 2.0-11.2%) in CRVO, 8.8% (95% CI 1.9-23.7%) in HRVO, and 1.9% (95% CI 0.4-5.4%) in BRVO]. Primary angle closure (PAC) had a frequency of 2.9% (95% CI 1.4-5.5%) in RVO. PAC/PACG had a frequency of 11.5% (95% CI 6.3-18.9%) in CRVO, 8.8% (95% CI 1.9-23.7%) in HRVO and 3.1% (95% CI 1.0-7.1%) in BRVO. PAC/PACG was significantly more prevalent in NONHS-RVO [18.9% (95% CI 9.4-32.0%)] than in ONHS-RVO [6.5% (95% CI 2.1-14.5%)], AV-RVO [3.1% (95% CI 0.9-7.8%)], and OC-RVO [2.3% (95% CI 0.1-12.3%)].

Conclusion: The overall frequency of PAC/PACG was much higher in patients with RVO (especially CRVO) than that in the general population. Eyes with PAC/PACG may undergo mechanical changes in the lamina cribrosa of the optic disc, resulting in RVO. Angle-closure conditions should be borne in mind when investigating Chinese patients with RVO.