Mean Ocular Perfusion Pressure Effect During Pars Plana Vitrectomy on the Foveal Avascular Zone: A Pilot Study.

To evaluate the effect of mean ocular perfusion pressure on the foveal avascular zone (FAZ) area in eyes with successful retinal detachment (RD) surgery. This prospective pilot fellow eye-controlled study measured the intraoperative mean ocular perfusion pressure in eyes having surgery for rhegmatogenous RD (RRD). Postoperatively, the FAZ area was measured; the change was calculated as the difference in the FAZ area between the operated eye and the contralateral control eye. The study comprised 8 patients with a mean age (±SD) of 53.38 ± 13.92 years. The mean superficial FAZ area was not different between operated eyes and control eyes, while the deep FAZ area was significantly larger in operated eyes. There was a strong negative correlation between the mean ocular perfusion pressure and the change in the deep FAZ area (Spearman ρ, -0.73;  = .04); the correlation between the mean ocular perfusion pressure and the change in the superficial FAZ area was not significant (Spearman ρ, -0.24;  = .57). A significant linear regression was found between the mean ocular perfusion pressure and the change in the deep FAZ area ( = 0.388). The predicted enlargement of the deep FAZ area was 0.03 mm with every 1 mm Hg decrease in the mean ocular perfusion pressure. Lower intraoperative mean ocular perfusion pressure is associated with enlargement of the deep FAZ area in eyes having successful RRD surgery.