Ultrasound biomicroscopy findings of 25 G Transconjuctival Sutureless (TSV) and conventional (20G) pars plana sclerotomy in the same patient

Abstract

Background: Transconjunctival Sutureless Vitrectomy (TSV) is a recent advancement in vitreo-retinal surgical techniques involving the use of 25 G instruments through self-sealing sclerotomies. It has been hypothesized that there may be less chance of vitreous and retinal herniation in the scleral wound as compared to conventional sclerotomy incision. However there are no reports on differences in 20 gauge and 25 gauge sclerotomies using ultrasound biomicroscopy (UBM). We report herein the differences in sclerotomies undertaken with 20 gauge (G) and 25 gauge instruments in the same patient.

Case presentation: Ultrasound biomicroscopy of the sclerotomy sites was done in the same patient in whom both 20 G and 25 G sclerotomies had to be constructed during pars plana vitrectomy and the differences were studied. On day 2, we observed a wide gape at the site that had been enlarged using a 20G MVR blade. In contrast, the other two sites made transconjunctivally using the 25G trocar showed only a mild gape. Significant gape continued to persist at the subsequent evaluations on day 7 and day 14 only at the port, which had been enlarged.

Conclusion: Healing of a 25 G sclerotomy is expectedly quite rapid, with inability to detect the site of sclerotomy in a short duration of 2 weeks post-operatively. This is as opposed to conventional sclerotomies, which might take up to 6-8 weeks post-operatively for complete opposition.

Figure 1

UBM image of 25G port on postoperative day 3 (a) and day 14 (b) shows complete healing of the sclerotomy. Converging vitreous strand is also evident. In contrast there is persisting gape of sclerotomy site enlarged to 20G (in the same patient) on day 3 and 14 (figure c and d).