Study identifies risk factors for failed IOP control after phacoviscocanalostomy

Higher IOP at baseline, more use of preoperative antiglaucoma medications, postoperative IOP spikes and younger age can elevate the risk for failed IOP control after phacoviscocanalostomy in patients with primary open-angle glaucoma and cataract, according to a retrospective study.

In order to identify possible risk factors for uncontrolled postoperative IOP, Masami Park, MD, PhD, and colleagues reviewed surgical records for 180 eyes of 180 patients with cataract and primary open-angle glaucoma who underwent phacoviscocanalostomy at Sensho-kai Eye Institute in Kyoto, Japan, between June 2000 and December 2004. After surgery, all patients stopped taking antiglaucoma medications; however, in specific cases, medication was continued if IOP levels exceeded individual target pressure levels.

At 5 years postop, mean IOP had significantly decreased from 20.2 mm Hg at baseline to 15.3 mm Hg (P < .0001), the authors noted.

Using the Kaplan-Meier survival curve, the investigators found that the 5-year success probability of achieving an IOP of 17 mm Hg or less or a 20% or greater IOP reduction was 47.2% with or without medications and 31.4% without medications.

The investigators identified baseline IOP levels (P =.0013) and age (P = .037) as risk factors for success probabilities both with and without medication use.

However, among patients who took no medications after surgery, baseline IOP levels (P < .001), the preoperative amount of antiglaucoma medications (P = .033), age (P = .003) and IOP spikes greater than 30 mm Hg (P = .028) were significantly linked with failure, according to the study

"Sex, peeling of juxtacanalicular tissue, ruptured Descemet membrane, fibrin formation and hyphema did not affect surgical outcomes," the study authors said in the September issue of Journal of Glaucoma.