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    This retrospective study analyzed outcomes for ab interno bleb revisions using the Grover-Fellman biplanar sclerostomy spatula.

    Study design

    The authors’ redesigned spatula is 20 mm in length and 0.5 mm in width at the distal tip, with a slight anterior arc designed to mimic the curvature of the globe. Compared with a cyclodialysis spatula, this instrument is much longer, which permits dissection underneath the scleral flap and further posterior breakdown of all scar tissue.

    Subjects included 21 eyes of 21 patients who underwent ab interno bleb revision with the spatula. Seventeen patients received injections of mitomycin C at least 1 week preoperatively.


    At 12 months postop, mean IOP decreased from 21.9 mm Hg at baseline to 12.1. Mean medication usage decreased from 3.7 to 0.86.

    All successful cases had low, diffuse, posterior blebs. Five patients experienced surgical failure due to persistently uncontrolled IOP, 4 of whom subsequently received a tube shunt. There were 2 cases of transient hypotony, which self-resolved without negative consequences.


    The study is limited by its retrospective nature, relatively small sample size, and noncomparative design.

    Clinical significance

    The study shows encouraging results with a novel instrument for performing a trabeculectomy revision with a relatively high degree of safety.

    A significant challenge in conventional bleb revision surgery is balancing the need for disruption of surgical adhesions while minimizing the risk of conjunctival perforation. The Grover-Fellman spatula was designed to meet each of these treatment goals.