Ciliary body position likely cause of angle closure in Chinese population

A high prevalence of appositional closure in iridotomized eyes after acute primary angle closure was documented in a recent study in Chinese patients. The study authors suggest that a likely mechanism for the closure is an anteriorly positioned ciliary body.

Barry Y.M. Yueng, FRCS, and colleagues at the Chinese University of Hong Kong examined 16 Chinese patients who had a history of acute primary angle closure and who had been subsequently treated with laser peripheral iridotomy. All surgeries were deemed successful. Comparisons were made to 14 healthy Chinese patients. Gonioscopy and ultrasound biomicroscopic exams were performed in the dark, to assess the angle’s structure.

Of the eyes with acute primary angle closure, 55.6% had an appositionally closed angle clinically; in 38.9%, only Schwalbe’s line was visible on gonioscopy. The structural differences between anterior segments in eyes with acute primary angle closure and healthy eyes were confirmed with ultrasound biomicroscopy. Specifically, “the trabecular-ciliary-process distances were markedly different between the two groups,” the researchers said.

The study is published in the October issue of Clinical & Experimental Ophthalmology.