Anterior Chamber Paracentesis Facilitates Laser Peripheral Iridotomy and Restores Vision in Mild-to-moderate Acute Primary Angle-closure Glaucoma

Purpose: Acute primary angle-closure glaucoma (PACG) is an ocular emergency that commonly presents in Asian populations. For patients with contraindications for mannitol infusion, it is imperative to perform an alternative therapy in order to rapidly decrease intraocular pressure (IOP) and prevent further visual complications. The purpose of this study is to evaluate the therapeutic efficiency of anterior chamber paracentesis (ACP) and mannitol infusion in patients with PACG. Methods: Patients who suffered from their first attack of acute PACG when receiving ACP or mannitol infusion (20%, 300mL) were included. They were divided into three subgroups: mild, moderate, or severe acute PACG, according to each patient's initial IOP upon presentation (mild group, 45-50mmHg; moderate group, 50-60mmHg; severe group, >60mmHg). IOP at multiple time points, best-corrected visual acuity (BCVA), severity of corneal edema, and waiting time for laser peripheral iridotomy (LPI) were recorded. Results: Compared with mannitol infusion (n=29), ACP treatment (n=30) achieved more rapid and effective IOP control within 2 hours, resulted in faster regression of corneal edema (grade: 0.98±0.729 [ACP] vs. 1.50±0.720 [mannitol], p=0.011), and patients were able to undergo LPI within a reasonable amount of time (1.4±0.93 days [ACP] vs. 2.5±1.17 days [mannitol], p=0.0002). All patients who received ACP or mannitol demonstrated improved BCVA within 2 weeks. Intriguingly, ACP restored visual acuity more effectively than mannitol infusion in patients with an initial IOP lower than 60mmHg. Conclusion: ACP effectively treats acute PACG by rapidly stabilizing the anterior chamber. When the initial IOP is above 60mmHg, ACP should only be considered when mannitol is contraindicated.