Evaluation of Peripheral Anterior Synechiae in Eyes With Acute Primary Angle Closure

Abstract

Abstract: : Purpose:To determine the extent of peripheral anterior synechiae (PAS) in eyes presenting with acute primary angle closure (APAC). Methods: This was a prospective observational case series of 72 Asian subjects with APAC. All subjects were treated with laser peripheral iridotomy (LPI) once the acute attack was broken with medical therapy. Just prior to LPI, gonioscopy was performed in darkened conditions to assess the angle width, and with indentation to determine the extent of PAS. Angle width was graded by the Shaffer scheme and the extent of PAS was recorded as the number of clock hours of synechial closure. Results: Subjects were predominantly Chinese (87.5%) and female (68.1%), with a mean age of 63.7 ± 11.5 years. The mean angle width in APAC–affected eyes prior to LPI was 0.66 ± 0.91 and that in fellow eyes was 0.95 ± 0.94 (p = 0.051). The amount of PAS in APAC eyes was found to be greater than in fellow eyes (5.35 ± 4.62 vs 1.94 ± 3.13 clock hours of PAS respectively, p < 0.001). In both attack and fellow eyes, increasing amounts of PAS were significantly correlated with greater narrowing of the angles. This association was stronger in APAC eyes (correlation coefficient –0.53, p < 0.001) than in fellow eyes (correlation coefficient –0.33, p < 0.01). Conclusions: Significant synechial angle closure is present in APAC eyes at presentation. This suggests that PAS formation may be an important underlying mechanism in the pathogenesis of APAC.

Keywords: clinical (human) or epidemiologic studies: risk factor assessment