Modified DRPT better for detecting primary angle closure

Conducting a modified dark room provocative test (DRPT) is better for the diagnosis of primary angle closure, compared to gonioscopic angle assessment, reveals a study in the Journal of Glaucoma.

Dr Dejiao Li led a cross-sectional observational prospective clinical study on 76 eyes of 76 patients. The anterior chamber angle configuration was measured in a light room and then after three minutes of dark adaptation using anterior segment optical coherence tomography (AS-OCT).

In light room conditions at baseline and after 1.5 hours of dark adaptation gonioscopy and Perkin's applanation tonometry were performed. The DRPT was identified as positive if intraocular pressure (IOP) increased by ≥8 mmHg after 1.5 hours of dark adaptation.

There were a significant number of eyes with an increased number of closed angle quadrants for the OCT examination at 3 minutes of dark adaptation, compared to gonioscopy at 1.5 hours of dark adaptation. For AS-OCT the area under the receiver operator characteristics curve was significantly larger, compared to gonioscopy.

A modified DRPT in combination with an anterior chamber angle assessment by OCT at 3 minutes of dark adaptation demonstrated a higher diagnostic precision for primary angle closure.