effect of phacoemulsification on intraocular pressure in eyes with functioning tube shunts

Purpose: to evaluate the effect of phacoemulsification on intraocular pressure (iop) in eyes with functioning tube shunts. methods: this was a retrospective chart review of primary open-angle glaucoma (poag) patients with a functioning tube who underwent phacoemulsification and had ≥24 months of follow-up. the primary end point was defined as surgical failure (iop > 21 mmhg) at month 24, progression to no light perception (nlp) vision, glaucoma reoperation, or implant removal. surgical failure defined as iop >18 and >15 mmhg, changes in visual acuity (va), iop, and number of medications were assessed. results: twenty-seven eyes of 27 patients with moderate or severe poag were included. the mean age of the patients was 64.2 ± 10.8 years. the interval between the tube shunt and phacoemulsification was 28.8 ± 25.0 months. at the end of the study, four (14.8%) eyes met the failure criteria; the average time to failure was 9.3 ± 3.8 months. the causes of failure were high iop in two (50.0%) and glaucoma reoperation in two (50.0%) eyes; however, no eyes progressed to nlp vision. surgical failure defined as iop >18 and >15 mmhg showed an increasing failure rate (18.5% and 48.5%, respectively). the mean iop and medications number remained stable at month 24 compared to baseline (p = 0.131 and p = 0.302, respectively). initially, va showed improvement, with the greatest improvement at 6 months (p = 0.001), but at 24 months the improvement was no longer significant (p = 0.430). conclusion: phacoemulsification in patients with functioning tubes did not change the mean iop in most of the patients (86.2%); the number of medications also did not increase.