Viscogonioplasty: an effective procedure for lowering intraocular pressure in primary angle closure glaucoma

To evaluate the safety and intraocular pressure (IOP) lowering effect of combined phacoemulsification and viscogonioplasty (Phaco-VGP) in managing primary acute closed-angle glaucoma (ACAG) unresponsive to conventional therapy (patent PI).

In all, 15 consecutive eyes of patients with refractory ACAG and greater than 270 degrees peripheral anterior synechiae (PAS) underwent VGP. The technique of VGP involved routine phacoemulsification with intraocular lens implantation (Phaco/IOL) under topical anaesthetic. Following IOL implantation a heavy viscoelastic was used to deepen the anterior chamber and then injected near the angle for 360 degrees (without touching the trabecular meshwork) to break the PAS. No surgical instrument was used to physically break the PAS. Upon completion of VGP, automated irrigation with balanced salt solution to remove the viscoelastic was performed.

Mean IOP reduced from 52.1 to 14.1 mmHg by Phaco-VGP at 6-months review. 14/15 patients were free of glaucoma medications at 6-month review. All angles showed exposure of the trabecular meshwork over 360 degrees postoperatively without evidence of residual synechiae. No untoward complications were observed in any patient.

VGP may have a role in controlling IOP effectively and safely in patients with refractory ACAG. It produces a large drop in the IOP and opening of the angle. It is a relatively simple technique to learn and we would recommend its use in the eyes of all patients who have had ACAG and are undergoing cataract extraction.