Prevalence and associated factors of choroidal caverns in patients with type 2 diabetes mellitus.

Purpose: To study the prevalence of choroidal caverns (CCs) in patients with type 2 diabetes (T2DM) and their association with demographic and clinical data. Methods: We included patients with T2DM and nondiabetic controls in a cross-sectional, monocenter study. The main outcome measure was the presence of CCs. Exploratory variables included age, sex, diabetic retinopathy (DR) status, duration of T2DM, visual acuity, arterial hypertension (aHT), hyperlipidemia, HbA1c, choroidal thickness (CT) and choroidal vascularity index (CVI). Group differences between eyes with and without CCs and associations with demographic and clinical variables were assessed. Results: After including a total of 205 eyes of 116 patients, the prevalence of CCs was 25% in the control, 28% in the T2DM without DR and 9.5% in the DR groups. The locations of the caverns were: choriocapillaris (N=2, 4.2%), Sattler's (N=29, 60.4%) and Haller's layer (N=17, 35.4%). 34.3% of patients had caverns in both eyes. We found no significant differences in systemic conditions (including aHT, hyperlipidemia, HbA1c or T2DM disease duration). CVI was the only parameter independently associated with the presence of choroidal caverns (OR 1.37). Conclusions: We found choroidal caverns in almost a quarter of patients with and without T2DM. CCs were mainly located in the Sattler’s layer. CVI was independently associated with the presence of CCs. These findings suggest that the presence of CCs may be a sign of a higher metabolic activity within the choroidal microenvironment, irrespective of T2DM status.