Pars Plana Vitrectomy Port Sizes: A Meta-Analysis of Randomized Controlled Trials

The uptake of small-gauge (SG; ie, 23-gauge [23-G], 25-gauge [25-G], and 27-gauge [27-G]) pars plana vitrectomy (PPV) has grown. We aim to investigate the advantages and disadvantages of various PPV port sizes in a meta-analysis of randomized controlled trials (RCTs).

A systematic literature search was performed for RCTs comparing PPV port sizes for any indication. Weighted mean differences (WMDs) and risk ratios (RRs) were calculated, and meta-analysis was performed with random-effects models.

A total of 1,678 eyes from 22 RCTs were included. Risk-of-bias assessment found some concerns in 13 studies. Compared with 20-gauge PPV, there was no significant difference in the final or change in best-corrected visual acuity (BCVA; five studies analyzed each) relative to that of SG PPV. SG PPV was associated with a significantly greater incidence of hypotony (RR = 3.79; 95% confidence intervals [CI], 2.02 to 7.10; P < .0001; six studies) and choroidal detachment (RR = 5.65; 95% CI, 1.01 to 31.71; P = .05; three studies). Compared with 25-G PPV, there was no significant difference in BCVA at any time point with 23-G (two studies), and significantly more frequent port suturing was required with 23-G (RR = 0.46; 95% CI, 0.25 to 0.84; P = .01; two studies). Compared with 25-G PPV, 27-G was associated with a significantly better final BCVA (WMD = -0.06 logMAR; 95% CI, -0.11 to -0.01; P = .02; five studies) and a significantly lengthened surgery (WMD = 4.11 minutes; 95% CI, 0.18 to 8.05; P = .04; three studies).

There was no significant difference in visual or surgical outcomes following 20-gauge PPV relative to SG PPV (Grading of Recommendations, Assessment, Development, and Evaluation recommendation: low certainty), and there was an increased risk of postoperative complications with SG PPV (moderate certainty). Compared with 25-G PPV, 23-G required more frequent port suturing (moderate certainty), whereas 27-G may be associated with a better final BCVA but longer surgery (low and moderate certainty, respectively). [.