25-, 23-, and 20-gauge vitrectomy in epiretinal membrane surgery: a comparative study of 553 cases

To compare the safety and functional outcomes of 25-gauge and 23-gauge (G) micro-incision vitrectomy surgery (MIVS) instrumentation with the standard 20-G vitrectomy system in the treatment of epiretinal membranes (ERM). A retrospective comparative study of 553 consecutive cases with epiretinal membrane who underwent pars plana vitrectomy. Twenty-gauge, 25-gauge and 23-gauge vitrectomy was performed respectively in 347, 91, and 115 eyes. Surgery duration, visual acuity improvement, intraocular pressure variation, intraoperative and postoperative complications were analyzed. The mean surgical time in the 23-G group and in the 25-G group was shorter than in the 20-G group (P < 0.001). Visual improvement was higher 8 days postoperatively in the 25-G group than in the 20-G and 23-G groups (P = 0.035), but not at 6 weeks postoperatively (P = 0.186). In the 20-G group, the IOP increased significantly on the first day postoperatively (P < 0.001), while in the 23-G group, the IOP decreased on the first day postoperatively (P = 0.073). In the 25-G group, the IOP did not change significantly (P = 0.807). The incidence of complications was not statistically significant between the three groups. Retinal breaks were significantly related to the induction of posterior vitreous detachment, independent of the system gauge. In ERM surgery, 23-G and 25-G (MIVS) systems are as safe and effective as the 20-G system, and significantly reduce surgical time. Although the 25-G system provides an earlier visual improvement, the 23- and 25- gauge systems are comparable, and the selection will depend on the surgeon's preference.