The radiographic restoration of the ventricular system after third ventriculostomy.

Ten adult patients were treated by third ventriculostomy for idiopathic aqueductal stenosis. Idiopathic aqueductal stenosis was diagnosed according to MR imaging; aqueductal stenosis secondary to tumor, hemorrhage, and/or infection was excluded. Following a third ventriculostomy under a flexible neuroendoscope, all patients were reviewed at 1, 3, 6, 12, and 24 months, and MR images with ventricular measurements were repeated for evaluation of the radiographic restoration of the ventricular system. The ventricular structures arranged in order of restoration were the size of the III ventricle, the upward deviation of the brain stem, and the size of the lateral ventricle in response to third ventriculostomy. The restoration of the whole ventricle steadied within two years. Our results contribute new information regarding restoration of the ventricular system under aqueductal stenosis and produce evidence that third ventriculostomy is a reasonable treatment based upon the patient's physiological condition.