Angle closure in Caucasians--a pilot, general ophthalmology clinic-based study.

PURPOSE To assess the rate of clinically significant angle closure in a predominantly Caucasian, clinic-based population, and consequently find out whether gonioscopy should be included in the routine ophthalmic examination. METHODS Patients aged ≥40 years with hyperopia ≥1 D were consecutively recruited in a community general ophthalmology clinic. Detailed darkroom gonioscopy was done, and primary angle closure was diagnosed if there was iridotrabecular apposition >180 degrees not secondary to an identifiable ocular disorder. Biometric parameters were measured and compared between the eyes with and without angle closure. RESULTS Eighty-four eyes from 84 patients (aged 61.3±8.9 y) were enrolled. There were 52 female (62%) and 32 male. Fourteen patients (16.7%) were diagnosed with angle closure. A statistically significant difference was observed between the eyes with and without angle closure in mean axial length (22.07±0.72 vs. 22.61±0.97, P=0.028), anterior chamber depth (ACD) (2.45±0.33 vs. 2.89±0.32, P<0.001), and lens thickness (4.97±0.3 vs. 4.62±0.4, P=0.002). Degree of hyperopia was marginally significant (3.13±2.3 vs. 2.45±1.5, P=0.09). In a logistic regression model, only ACD remained statistically significantly different (P=0.016). We tested the ability of ACD to distinguish eyes with angle closure. The area under the receiver operating characteristic curve was 0.824; using a cutoff ACD value of 2.65 mm, sensitivity was 0.786 with a specificity of 0.812. CONCLUSIONS Clinically significant angle closure, mandating close follow-up or preventive procedures, may be more common in Caucasians than currently thought. We recommend that gonioscopy should be included in the routine ophthalmic examination of all adults with hyperopia.