REDUCTION OF VITREOUS CONTAMINATION RATE AFTER 25-GAUGE VITRECTOMY BY SURFACE IRRIGATION WITH 0.25% POVIDONE-IODINE

Purpose: To examine whether repeated ocular surface irrigation with 0.25% povidone-iodine, which is highly bactericidal and nonoculotoxic, reduces bacterial contamination of the vitreous during 25-gauge vitrectomy. Methods: Overall, 4,407 eyes undergoing 25-gauge vitrectomy were studied; of these, 2,801 were irrigated with infusion fluid (group A) and 1,606 with 0.25% povidone-iodine (group B). In each group (A and B), 103 eyes were studied bacteriologically, using ocular surface fluid samples after placing lid speculum (S1), after operative field irrigation (S2), and in vitreous samples at the beginning (V1) and at the completion of vitrectomy (V2). Results: Bacterial contamination rate in S1 did not differ significantly between the groups A (5.5%) and B (6.8%). However, the contamination rates in S2, V1, and V2 were apparently lower in group B (0%, 0%, and 0%, respectively) than in group A (2.0%, 1.0%, and 2.0%, respectively). Incidence of endophthalmitis was 0 of 2,801 eyes in group A and 0 of 1,606 eyes in group B. Conclusion: In 25-gauge vitrectomy, repeated operative field irrigation with 0.25% povidone-iodine reduced bacterial contamination in vitreous to extremely low level. RETINA 33:143-151, 2013