A flat anterior chamber following filtering surgery has many etiologies. Included in the differential diagnosis are overfiltration, wound leak, choroidal effusions/hemorrhage, and pupillary block; however, the key is the central anterior chamber depth. If the intraocular pressure (IOP) is normal to high, the anterior chamber shallow centrally, and choroidal effusions/hemorrhage ruled out, then the likely diagnosis is aqueous misdirection syndrome. Aqueous misdirection syndrome (AMS), previously referred to as malignant glaucoma, was first described by von Graefe in 1869 as an unusual complication of eye surgery, in the presence of a patent peripheral iridectomy, with elevated IOP and a fl at anterior chamber. This condition has been referred to as ciliary block glaucoma because the ciliary processes may be in apposition to the anterior vitreous or lens, with the lens moving into the ciliary sulcus. Diversion of aqueous posteriorly into the vitreous cavity, thus increasing the volume of the vitreous, is considered the main mechanism in the development of AMS. This diversion pushes the lens forward, leaving the central as well as the peripheral anterior chamber shallow or even flat (Figure 11.1). Once a diagnosis is made, treatment is effective at resolving the problem. Filtering surgery, either alone or in combination with another surgery, has been shown to be the inciting event for AMS in 10 of 24 cases (42%) reported in a series from Harbour. Tsai et al reported 12 of 19 cases (63%) with AMS followed filtering surgery. One case of AMS among 105 (1%) trabeculectomy procedures was reported by Gedde et al in the Tube Versus Trabeculectomy (TVT) Study. Two instances of AMS out of 465 (0.4%) trabeculectomy procedures were reported in the Collaborative Initial Glaucoma Treatment Study (CIGTS). The rates from these studies of open-angle glaucoma patients may not apply to other populations in which angle closure glaucoma (a known risk factor for AMS) is more prevalent. Typically, AMS develops within the first few weeks of filtering surgery.
CASE REPORT Management Cataract Complication and Malignant Glaucoma After Viterectomy Surgery and C3F8 Gas Tamponnade
