Endoscopic third ventriculostomy.

We prospectively studied 8 patients who had an endoscopic third ventriculostomy performed between 1996 and 1997 in Songkhlanagarind Hospital. The surgical technique was described. Seven operations were successful and one operation failed. Success was found in cases of pure aqueductal stenosis, aqueductal stenosis with Dandy Walker malformation, and posterior fossa tumor. In a patient where an endoscopic third ventriculostomy failed, aqueductal stenosis with marked hydrocephalus was found. Marked dilation of the third ventricle could compress the aqueduct of Sylvius. Although there was communicating hydrocephalus, it looked like non-communicating hydrocephalus. To avoid a valvular shunting complication, we suggest performance of an endoscopic third ventriculostomy in selected non-communicating hydrocephalus patients.