Methods: Four patients with hydrocephalus related to aqueductal stenosis who underwent neuroendoscopic aqueductoplasty procedure in our neuroendoscopy unit were presented. Postoperatively, patency of the restored cerebrospinal fluid flow was confirmed with cine phasecontrast MR imaging.

Results: In three cases endoscopic aqueductoplasty was performed successfully and there was no need for third ventriculostomy. In one case that exhibited a longsegment aqueductal stenosis, aqueductoplasty procedure had to be abandoned and third ventriculostomy was performed. The only surgical complication was an asymptomatic forniceal contusion in one patient. None of the patients required shunting after the neuroendoscopic procedure.

Conclusion: Our preliminary results show that neuroendoscopic aqueductoplasty is an effective alternative to third ventriculostomy for the treatment of hydrocephalus caused by short or membranous stenoses of the aqueduct of Sylvius. We also suggest that cine phase-contrast MR imaging is a sensitive technique for assessing postoperative CSF flow through the aqueduct. Keywords : Aqueductal stenosis, endoscopic aqueductoplasty, hydrocephalus, neuroendoscopy