Primary vitrectomy for rhegmatogenous retinal detachment in pseudophakic eyes: 20-gauge versus 25-gauge vitrectomy.

PURPOSE: To report anatomical and functional outcome of 20-gauge versus 25-gauge primary pars plana vitrectomy for management of complex rhegmatogenous retinal detachment in pseudophakic eyes. METHODS: Prospective single-centre randomized comparative pilot trial. Fifty patients with retinal detachment (RD) not complicated by proliferative vitreoretinopathy grade B or C, who cannot be treated with a single meridional sponge, were randomized (1:1) from November 2006 to January 2010 to either 20-gauge or 25-gauge vitrectomy as first surgical intervention and followed up over a 12-month period, evaluating change in best-corrected visual acuity, anatomical success and intraocular pressure dysregulation. RESULTS: Mean visual acuity improved by 0.88 (SD 0.67) from 1.22 logMAR (SD 0.63) to 0.34 logMAR (SD 0.31) in the 20-gauge group and by 0.53 (SD 0.91) from 0.86 logMAR (SD 0.73) to 0.34 logMAR (SD 0.46) in the 25-gauge group. Final anatomical success rate was 100% and primary success rate was 69% at 6 months of follow-up. In the 20-gauge group, the retina was attached after one single procedure in 18 eyes (72%) and in 21 eyes (84%) of the 25-gauge group. Two patients in the 25-gauge group had hypotony at the first postoperative day which normalized within 6 weeks. CONCLUSION: In our series, transconjunctival sutureless 25-gauge and 20-gauge vitrectomy showed comparable results in pseudophakic RD not suitable for single sponge surgery with respect to visual outcome and retinal reattachment. Postoperative hypotony does not seem to be a significant problem of transconjunctival sutureless vitrectomy.