The Effect of Phacoemulsification on Intraocular Pressure in Eyes with Hyperfiltration Following Trabeculectomy: A Prospective Study.

Abstract

The aim of this study was to evaluate the effect of visually non-significant cataract extraction in patients with hypotony maculopathy and reduced visual acuity due to over-filtering blebs after trabeculectomy. Patients with intraocular pressure (IOP)<6mmHg and documented hypotony maculopathy due to over-filtering blebs after trabeculectomy were prospectively recruited. Eligible patients underwent visually non-significant cataract phacoemulsification, no earlier than 12weeks from the diagnosis of hypotony maculopathy. IOP and visual acuity before and after phacoemulsification were compared at 1 and 3months from surgery. Correlations between age, time interval between surgeries, baseline IOP, bleb type and IOP and visual acuity changes at 3months after phacoemulsification were investigated. From January 2010 to September 2014, 20 consecutive adult patients met the inclusion criteria. Before phacoemulsification, mean IOP was 3.1±1.6mmHg. Following phacoemulsification, mean IOP increased to 8.6±4.1mmHg at 1month (p<0.01) and to 9.1±4.3mmHg at 3months (p<0.01). IOP elevation following phacoemulsification was observed in 16 of 20 eyes (80%). Mean visual acuity improved from Snellen 0.5±0.1 to 0.6±0.1 at 1month (p<0.01) to 0.7±0.2 at 3months (p<0.01) after phacoemulsification. In 4 eyes in which the IOP was not elevated, surgical revision of the previous trabeculectomy was performed. No significant correlations between investigated variables, visual acuity and IOP changes at 3months after phacoemulsification were found. Phacoemulsification of visually non-significant cataract appears to be a safe and effective technique for managing chronic ocular hypotony with deep anterior chamber due to over-filtering blebs.