Objective: To compare the anatomical and functional outcome of scleral buckle (SB) surgery with that of pars plana vitrectomy (PPV) alone in the treatment of primary rhegmatogenous pseudophakic retinal detachment (RD). Methods: In this prospective, randomized clinical trial, 150 eyes of 150 patients with pseudophakic RD and proliferative vitreoretinopathy (PVR) stage B or less were randomized to SIB surgery (75 eyes) or primary PPV (75 eyes). SIB surgery involved break localization, cryotherapy, placement of a circumferential 240 style 2.5-mm solid silicone band, combined with a local buckle when indicated, and transscleral drainage of subretinal fluid. PPV included extensive vitreous removal, perfluoro-n-octane injection or endodrainage of subretinal fluid to flatten the retina, cryopexy treatment of breaks, and fluid/air exchange with injection of 20% SF,. Postoperative follow-up was 1 year. Break diagnosis, operating time, intraoperative and postoperative complications, retinal reattachment rate for single as well as multiple surgeries, axial length changes, and best-corrected visual acuity at 1 year after surgery were the main outcome measures. Results: The number of eyes that were diagnosed with additional breaks interoperatively was higher in the PPV group (P = 0.004, A, chi(2) test). Mean operating time was significantly less (P = 0.0001, t-test) in the PPV group. With a single surgery, the retina was reattached in 62 eyes (83%) in the SIB surgery group and in 71 eyes (94%) in the PPV group (P = 0.037, Fisher exact test). With subsequent surgeries, final anatomical reattachment was achieved in 71 cases in the SB surgery group and in 74 cases in the PPV group (P = 0.37, Fisher exact test). Mean axial length change at 1 year was 0.95 mm in the SIB surgery group and 0.1 mm in the PPV group (P = 0.0001, t-test). Mean final best-corrected visual acuity (logMAR) was 0.40 in the SB surgery group and 0.33 in the PPV group (P = 0.26, t-test). Conclusions: Primary PPV offers potential advantages over SB surgery in the treatment of pseudophakic RD, including less operating time, accurate diagnosis of breaks, higher reattachment rate with a single surgery, and no postoperative axial length changes. Retinal reattachment rate with multiple surgeries and final visual acuity at 1 year were similar for SIB surgery and PPV.