Acute primary angle closure-treatment strategies, evidences and economical considerations.

Acute primary angle closure requires emergency management that involves a rapid lowering of the intraocular pressure and resolution of relative pupil block - the most common mechanism of angle closure. Emergency strategies for lowering intraocular pressure include medical treatment and argon laser peripheral iridoplasty. Anterior chamber paracentesis and diode laser transcleral cyclophotocoagulation may be considered in special situations. Relative pupil block can be relieved by peripheral laser iridotomy and primary lens extraction; the latter is a more effective treatment according to the results of clinical trials. However, primary lens extraction can be technically demanding in the acute setting. Peripheral laser iridotomy has a role in relieving pupil block and should also be considered in most cases. Lens extraction may be combined with procedures such as goniosynechialysis, trabeculectomy or endoscopic cyclophotocoagulation. In this review, we aim to discuss the available evidence regarding the different treatment modalities. We also discuss the economic consideration, including cost-effectiveness and life expectancy, in the management of acute primary angle closure.