Retinal vein occlusion in patients with primary angle closure: a prospective case-control study

Abstract

Objective: To compare the prevalence of angle closure in eyes with retinal vein occlusion (RVO) with control eyes and assess the possible association between angle-closure and RVO.

Patients and methods: This prospective, blinded case-control study included patients with a history of RVO (cases) and control individuals matched for age and refractive error. Clinical characteristics and angle-based structures derived from anterior-segment optical coherence tomography (AS-OCT) were analyzed.

Results: Eighty-eight patients (44 per group) were included. The average age of the RVO and control groups was 59.8 ± 11.6 years and 60.8 ± 9.0 years, respectively (p = 0.667). There were no significant differences in terms of clinical characteristics between the 2 groups, including intraocular pressure (p = 0.837) and Shaffer gonioscopy grading (p = 0.620). None of the AS-OCT-derived angle characteristics were significantly different between the 2 groups. The number of angle-closure diagnoses between the RVO group (1 primary angle closure and 7 primary angle-closure suspects) and the control group (6 primary angle-closure suspects) did not differ significantly (p = 0.560). Anterior-chamber depth (ACD) was shallower in RVO eyes (2.72 ± 0.31 mm) than in the contralateral non-RVO eyes (2.76 ± 0.31 mm; p = 0.014).

Conclusions: This prospective, blinded, matched case-control study did not evidence any significant differences in clinical and AS-OCT-derived structural measures between RVO and control eyes. However, RVO eyes, compared with their contralateral non-RVO eyes, had a slightly shallower ACD. These findings collectively suggest that an association between primary angle-closure mechanisms and RVO is unlikely. However, the shallower ACD in RVO eyes could potentially put them at higher risk for intermittent or permanent pupillary block.