• Written By: Jeffrey Freedman, MD, BCh, PhD, FRCSE, FCS

    The authors describe their use of a surgical technique combining partial anterior pars plana vitrectomy, hyaloido-zonulectomy and peripheral iridectomy in five patients with aqueous humor misdirection refractory to medical treatment. The article includes clear diagrams showing the steps of the surgical procedure.

    Each patient had experienced increased IOP and shallowing of the anterior chamber after cataract extraction or trabeculectomy. The aqueous misdirection was promptly resolved in all cases after the combination surgical treatment.

    The surgical technique involves the use of a vitrector to perform anterior vitrectomy, hyaloido-zonulectomy and iridectomy. The use of an anterior chamber maintainer during the procedure proves to be innovative and useful. The procedure removes anterior vitreous and breaks the hyaloid face over a wide area. The creation of the iridectomy removes all impediments to aqueous flow from the vitreous cavity to the anterior chamber.

    The authors note the frequent lack of success when these patients receive medical therapy and the lack of understanding of the pathogenesis of aqueous misdirection. However, the creation of a pathway between the anterior and posterior chambers, allowing the free flow of aqueous to the anterior chamber, appears to be important for successful treatment. This explains why simply performing a partial or total vitrectomy without creating a pathway to the anterior chamber may fail to alleviate aqueous misdirection.