Secondary Angle Closure: Imaging, Diagnosis, Etiology, and Treatment

Primary angle closure occurs in eyes that have anatomic predisposition with narrow angles, often with a component of relative pupillary block. Secondary causes of angle-closure glaucoma result from other underlying mechanisms that may or may not have a component of pupillary block. Secondary angle closure is caused by a separate identifiable pathology, other than primary anatomic predisposition. The angle may be closed by space-occupying entities that push the iris forward, or mechanisms that pull the peripheral iris toward the trabecular meshwork anteriorly.