Changes in Day 1 Post-Operative Intraocular Pressure Following Sutureless 23-Gauge and Conventional 20-Gauge Pars Plana Vitrectomy

Background/Aims: The benefits associated with transconjunctival sutureless vitrectomy techniques are continuing to be defined. The purpose of this study was to compare the incidence of extreme changes in day 1 intraocular pressure (IOP) following 23-gauge sutureless vitrectomy compared with conventional 20-gauge vitrectomy. Methods: Fifty consecutive 23-gauge and 50 consecutive 20-gauge cases were included; eyes with a history of previous vitreoretinal surgery were excluded. 23-gauge surgery was completed with passive fluid air exchange where no long acting tamponade was indicated. The surgery remained sutureless unless a leak was visible at the end of the procedure. Data were collected by retrospective case note review. Statistical analysis was carried out using Fisher's exact and chisquare tests. Results: Twenty-two percent (11/50) of 23-gauge vitrectomies required suturing of one or more ports. On the first postoperative day hypotony (IOP<5mmHg) occurred in 1/50 eyes in the 20- and 23-gauge groups. Raised pressure (IOP>21mmHg) occurred in 30% (15/50) of eyes in the 20-gauge group and 8% (4/50) of eyes in the 23-gauge group; IOP>30mmHg only occurred in the 20-gauge group (3/50). Conclusion: Fluid air exchange following 23-gauge vitrectomy is associated with very low risk of day 1 hypotony. This predominantly sutureless technique appears to reduce the incidence and magnitude of early post-operative IOP elevation compared with conventional 20-gauge vitrectomy.