Atypical angle closures.

PURPOSE OF REVIEW: Primary angle closure typically causes acute intraocular pressure rise in the phakic elderly. Alternative diagnoses, however, for which iridotomy is usually ineffective, occur commonly in younger, nonhyperopic, and pseudophakic patients. RECENT
FINDINGS: High-resolution ultrasonography has advanced our understanding of these entities. Management of platueau iris, present in over half of angle closures with patent iridotomy, may depend on disease stage. Early postoperative pseudophakic patients with myopic shift and narrow angle should be treated with laser capsulotomy for capsular block. Bilateral angle closure is usually due to an offending systemic pharmacologic agent, which must be stopped to resolve the closure. Ciliary body swelling often produces angle closure by blocking the access of aqueous to the anterior chamber, sometimes paradoxically after hypotony. Annular choroidal effusions, difficult to detect without ultrasound, may mimic angle closure. Although cycloplegic and corticosteroid therapy may resolve some entities, pars plana vitrectomy and lensectomy may be necessary to resolve severe ciliary block. We also discuss unique variants of angle closure in patients with retinal disease.
SUMMARY: Atypical angle closures should always be considered. Careful examination techniques and new technology can detect the mechanisms involved and direct treatment.