Angle-Closure Glaucoma–Simpler Answers to Complex Mechanisms: LXVI Edward Jackson Memorial Lecture

Purpose

To present evidence-based concepts that will explain mechanisms of angle-closure glaucoma.

Design

Review of published evidence and personal perspective.

Methods

Literature review and clinical research using imaging devices.

Results

When the pupil dilates, the iris typically decreases its volume by losing extracellular fluid. Eyes with angle-closure lose less iris volume with pupil dilation, contributing to obstruction of the trabecular meshwork. Expansion of choroidal volume is a dynamic phenomenon and is a major risk factor in angle-closure. The mechanism of malignant glaucoma seems likely to result from poor conductivity of fluid through the vitreous, and past suggestions that it results from “misdirected” aqueous are not consistent with physiological principles.

Conclusions

Angle-closure and angle-closure glaucoma result from disturbed physiological mechanisms more than from simple anatomic measures, and future predictive testing can exploit knowledge of these factors.