Ultrasound biomicroscopic findings of conventional and sutureless sclerotomy sites after 20-, 23-, and 25-G pars plana vitrectomy

Purpose We examined sclerotomies that were performed using 20-G systems and non-stitch 23-G systems, one-step (23/1) and two-step procedures (23/2), as well as one-step 25-G systems for pars plana vitrectomy (PPV) with ultrasound biomicroscopy (UBM) to assess subconjunctival bleb formation, vitreous incarceration, and wound closure. Methods This study is a prospective, non-randomized, monocentre study comprising 40 patients; we examined sclerotomies using UBM after 20-G, 23/1-G, 23/2-G, and 25-G PPV in 10 patients each on days 1 and 30 postoperatively. Results Subconjunctival bleb formation was not detected in any of the eyes on the first day after surgery in the 20-G and 23/2-G groups and was observed in 5 (50%, 25 G) and 2 eyes (20%, 23/1 G). By day 30 postoperatively, all blebs had spontaneously resolved. The sclerotomy tunnel could be detected by UBM at day 1 postoperatively in 10 (100%, 20 G), 9 (90%, 25 G), 7 (70%, 23/1 G), and 7 eyes (70%, 23/2 G). Thirty days postoperatively, it was present in 10 (100%, 20 G), 1 (10%, 25 G), 3 (30%, 23/1 G), and 1 (10%, 23/2 G) eye. Vitreous incarceration occurred in 2 (20%, 20 G), 7 (70%, 25 G), 4 (40%, 23/1 G), and 2 (20%, 23/2 G) eyes. Conclusions Anatomical closure of sclerotomies without subconjunctival bleb formation as seen on UBM was achieved at day 1 after 23/2-G and 20-G PPV and after 30 days postoperatively in all other non-stitch PPV techniques. Vitreous incarceration is common after 25-G PPV. Non-stitch sclerotomies can frequently no longer be detected by UBM 30 days postoperatively. Eye (2010) 24, 1268-1272; doi:10.1038/eye.2009.291; published online 11 December 2009