Phacoemulsification versus combined phacoemulsification and viscogonioplasty in primary angle-closure glaucoma: A randomized clinical trial

Purpose: To compare the effect of phacoemulsification (Phaco) versus combined phacoemulsification and viscogonioplasty (Phaco- VGP) on long-term intraocular pressure (IOP) in primary angleclosure glaucoma (PACG). Methods: In this prospective randomized clinical trial, 92 eyes of 82 patients with PACG and coexisting cataract were randomized to undergo Phaco alone (46 eyes) or Phaco-VGP (45 eyes) and completed the trial. Anterior segment optical coherence tomography was performed preoperatively and at 1 year after surgery. Main outcome measures were IOP and the number of IOP-lowering medications. Results: Phaco alone reduced the mean IOP from a preoperative level of 22.3±6.3 to 14.0±3.7mm Hg at 12 months after surgery (P<0.001). Phaco-VGP reduced the mean IOP from a preoperative level of 23.3±7.3 to 14.5±2.5mm Hg (P<0.001). There were no statistically significant differences between the 2 groups in IOP and number of medications at all follow-up times. Trabecular-iris space-area measured by anterior segment optical coherence tomography increased significantly after Phaco alone and Phaco-VGP. The amount of the increase was higher in the Phaco-VGP. Although peripheral anterior synechiae (PAS) extent decreased significantly by Phaco alone, Phaco-VGP resulted in significantly greater reduction in PAS extent (P=0.004). The only variables that predicted change in IOP in the whole group were preoperative IOP (b=0.891, P<0.001) and female sex (b=2.754, P=0.02). Conclusions: Phaco alone and Phaco-VGP resulted in widening of the drainage angle, reduction of IOP, and PAS extent in PACG eyes. Phaco-VGP resulted in significantly more reduction of PAS and more opening of angle. However, it seems that additional VGP has no significant effect on long-term IOP.