Clinical comparison of 27-gauge and 23-gauge instruments on the outcomes of pars plana vitrectomy surgery for the treatment of vitreoretinal diseases.

PURPOSE OF REVIEW: To compare outcomes of 27-gauge and 23-gauge pars plana vitrectomy (PPV) for treatment of vitreoretinal diseases. RECENT FINDINGS: Sixty-eight patients undergoing microincisional PPV for treatment of vitreoretinal diseases were randomized 1 : 1 to 27-gauge or 23-gauge surgery with a 7500 cuts-per-minute vitrectomy probe. The most common reasons for vitrectomy were epiretinal membrane (49%) and vitreous hemorrhage (24%). Mean +/- standard deviation (SD) changes from immediate preoperative to immediate postoperative intraocular pressure were -0.40 +/- 6.60 mmHg in the 27-gauge and -3.05 +/- 7.64 mmHg in the 23-gauge group (adjusted mean difference 2.42 mmHg, 95% lower confidence limit 0.64, P = 0.013), but these changes were not associated with primary reason for vitrectomy (P = 0.065). Mean +/- SD conjunctival edema grades in the 27-gauge and 23-gauge groups 1 week after surgery were 0.02 +/- 0.124 and 0.10 +/- 0.246, respectively (least squares mean difference -0.09, 95% upper confidence limit -0.03, P = 0.004), and were 0.01 +/- 0.122 and 0.12 +/- 0.338, respectively, at the probe incision site. Conjunctival edema grades were similar in both groups at 1 and 3 months. Mean +/- SD pain ratings on postoperative day 1 - an indicator of patient comfort - were similar in the two groups. SUMMARY: Smaller diameter vitrectomy instruments are associated with smaller reductions in immediate postoperative intraocular pressure.