Longstanding overt ventriculomegaly in adults: pitfalls in treatment with endoscopic third ventriculostomy.

OBJECT: The recently described condition of longstanding overt ventriculomegaly in adults (LOVA) has not been defined in terms of the need for intervention, timing of intervention, and ideal treatment. The purpose of this review was to evaluate the role of endoscopic third ventriculostomy (ETV) in the treatment of LOVA.
METHODS: Data collected in six patients with LOVA who had undergone ETV were reviewed retrospectively in terms of the definition of treatment success, rates of success, complications, and outcome. All six patients presented with headache disorders. In all patients, triventricular hydrocephalus had been diagnosed as aqueductal stenosis, and head circumference measurements were above the 98th percentile. All six had undergone successful ETV as documented by the free flow of cerebrospinal fluid into the basal cisterns, which remained open throughout the follow-up period. After the procedure, one patient experienced a mild degree of difficulty with short-term memory. Five patients remained symptomatic or had symptoms requiring further treatment 3 months to 3 years after ETV. Four patients received ventriculoperitoneal shunts, and one underwent venous stenting for high intracranial pressure after successful ETV. In two patients in whom aqueductal stenosis had been diagnosed, the sylvian aqueduct was patent after the procedure.
CONCLUSIONS: In LOVA patients who present with headaches, ETV may not lead to improvement in the headaches. Despite the presence of triventricular hydrocephalus, closure of the aqueduct may be a secondary phenomenon, and flow through the aqueduct may be reestablished after ETV. If intracranial hypertension persists after successful ETV, its cause may be increased venous sinus pressure.