23-gauge transconjunctival vitrectomy in eyes with pre-existing functioning filtering blebs

BACKGROUND: We investigated the outcome of 23-gauge transconjunctival pars plana vitrectomy (23G PPV) for the treatment of vitreoretinal disorder in patients with prior trabeculectomy. METHODS: We retrospectively reviewed medical records of 23G PPV in 11 eyes that had functioning filtering blebs after trabeculectomy. The main outcome measures were the visual acuity, intraocular pressure (IOP) and subconjunctival fluid height in bleb by anterior segment optical coherence tomography (OCT) before and after the surgery. RESULTS: Eyes that had 23G PPV showed improvement of visual acuity after the surgery (P =0.003). Mean IOP was 13.82 mmHg before 23G PPV and 15.82 mmHg at 6 months postoperatively, which was statistically insignificant (P = 0.758). The bleb was observed before and after surgery using anterior segment OCT, and the difference in subconjunctival fluid was not statistically significant (P =0.172). CONCLUSIONS: 23G PPV did not adversely affect bleb function in eyes with prior trabeculectomy.