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The endoscopic trans-fourth ventricle aqueductoplasty and stent placement for the treatment of trapped fourth ventricle: long-term results in a series of 18 consecutive patients.

BACKGROUND
Different surgical approaches have been described in the past to treat a trapped fourth ventricle (TFV) but, unfortunately, these techniques showed a high rate of dysfunction and complications. During the last 10 years the development of neuroendoscopy has dramatically changed the outcome of these patients.


MATERIALS AND METHODS
We conducted a retrospective evaluation of the safety, effectiveness, and long-term outcome of endoscopic aqueductoplasty and stent placement, performed in 18 consecutive patients with symptomatic TFV through a trans-fourth ventricle approach between 1994 and 2010. Thirteen patients underwent endoscopic aqueductoplasty and stent placement and 5 patients underwent aqueductoplasty alone using a tailored suboccipital approach through the foramen of Magendie in prone or sitting position.


RESULTS
The mean age of the patients at the time of surgery was 15.2 years. All patients but 3 had a supratentorial ventriculoperitoneal shunt. Fifteen patients presented with slit supratentorial ventricles. At a mean followup of 90.8 months all patients experienced a stable clinical improvement. Only two complications were observed: A transient diplopia due to dysconjugate eye movements in one patient and a transient trochlear palsy in another one.


CONCLUSIONS
Our experience and the literature review suggest that endoscopic trans-fourth ventricle aqueductoplasty and stent placement is a minimally invasive, safe, and effective technique for the treatment of TFV and should be strongly recommended, especially in patients with supratentorial slit ventricles.