Trapped fourth ventricle treated with shunt placement in the fourth ventricle by direct visualization with flexible neuroendoscope.

Shunt placement was the most common procedure used for ventricular dilatation, but in many neurosurgical centers it has been substituted by flexible neuroendoscope; however, none of them had solved the problem of the trapped and dilated fourth ventricle. The combination of the ventricle-peritoneal catheter placement in the center of the fourth ventricle by direct visualization with a flexible neuroendoscope using a single coronal burr-hole has solved this problem. Eleven patients with a trapped fourth ventricle, with previous third ventriculostomy and aqueductal plasty, were treated with this procedure; all patients were evaluated clinically and with computed tomography 8 to 24 months (mean, 18 months) later. Here, we describe the technical procedure.