Indications for Neuroendoscopic Aqueductoplasty without Stenting for Obstructive Hydrocephalus due to Aqueductal Stenosis

Abstract

Neuroendoscopic aqueductoplasty (EAP) is a curative and radical procedure for obstructive hydrocephalus due to aqueductal stenosis that re-establishes the physiological circulation of cerebrospinal fluid (CSF). We assessed the indications for safe neuroendoscopic aqueductoplasty without stenting to treat aqueductal stenosis. In the past 5 years, 6 (5.5 %) of the 110 patients with obstructive hydrocephalus due to aqueductal stenosis were judged to be suitable for EAP on the basis of the MRI features of the aqueduct and intraoperative neuroendoscopic findings from the third ventricle for the aqueductal stenosis. The remaining 104 patients were treated by neuroendoscopic third ventriculostomy. Indications for safe EAP were determined retrospectively based on the clinical features, preoperative MRI, intraoperative neuroendoscopic findings and outcome of the 6 patients who underwent EAP. There were no deaths due to EAP. All of the patients showed improvement or resolution of their preoperative symptoms. In 5 patients, dilatation of the third ventricle and lateral ventricles diminished, and prestenotic dilatation of the aqueduct also disappeared. After an average follow-up period of 39.5 months, recurrence of aqueductal stenosis has not been observed. In one patient, there was a complication of oculomotor nerve paresis after EAP. EAP can be considered the best surgical procedure for restoring physiological circulation of CSF in patients with obstructive hydrocephalus caused by aqueductal stenosis. However, EAP candidates must be selected very carefully using the following indications: 1) obstructive triventricular hydrocephalus with increased intracranial pressure, 2) translucent membranous stenosis or aqueduct obstruction, and 3) prestenotic dilatation of the aqueduct.