Scanning laser polarimetry in patients with acute attack of primary angle closure

Abstract

Purpose: To compare the retinal nerve fiber layer measurements of attacked eyes with their fellow eyes after a single unilateral attack of acute primary angle closure (APAC).

Methods: Patients with a single episode of APAC in 1 eye, successfully treated with laser peripheral iridotomy, were recruited. Eyes with persistently raised intraocular pressure (IOP) after resolution of the acute attack were excluded. Scanning laser polarimetry was carried out at 6 months after remission of the acute attack. The various parameters between the attacked and the fellow eyes were compared using the Student t-test.

Results: Twenty-six patients (24 female and 2 male, mean age 66.9+/-8.1 years) were recruited. The duration of the APAC ranged from 5 to 98 hours (mean, 36.3 hours). The mean presenting IOP during the acute attack was 62.0+/-9.4 mm Hg. Only the mean inferior ratio and the ellipse modulation showed a statistically significant difference between the attacked and the fellow eyes among the 12 standard scanning laser polarimetry measurement parameters.

Conclusion: No severe retinal nerve fiber layer damage was documented in eyes that suffered a single episode of APAC with duration of attack up to 48 hours. With duration of attack longer than 48 hours, retinal nerve fiber layer damage was detected.