Rapid treatment of acute primary angle closure may ward off increased cup-to-disc ratio

Ophthalmology. 2011;118(2):254-259.

If treated promptly, a single episode of acute primary angle closure may not necessarily increase cup-to-disc ratio, but retinal nerve fiber layer loss may occur, a study found.

"These findings are specific to patients who do not have features suggestive of any form of pre-existing glaucoma and who experience a single episode of [acute primary angle closure] in which the IOP remains elevated for a short duration only," the study authors said.

In an observational case series, 20 participants with unilateral acute primary angle closure were observed to establish changes to the optic nerve head and retinal nerve fiber layer (RNFL) after prompt treatment, the authors said.

The affected eye was examined, while the other eye served as a control. Participants attended three subsequent follow-up assessments over a 12-month period at 2 weeks, between 2 and 3 months, and between 6 and 12 months.

The mean overall RNFL thickness in affected eyes decreased from 106.6 µm to 92.9 µm between the second and third visits (P < .01), according to the study.

Overall, the mean superior quadrant RNFL thickness decreased from 134.8 µm to 113 µm (P < .01), while inferior quadrant RNFL thickness was reduced from 139.1 µm to 115.6 µm (P < .01).

There were no significant changes in cup-to-disc ratio, neuroretinal rim area, or macular thickness or volume between follow-up visits, according to the study.