Hydatid cyst of the aqueduct of Sylvius. Case report.

In countries where hydatid disease is prevalent, cerebral hydatid cyst may be responsible for as much as 10% of all intracranial expansive processes. These cysts may be localized in various anatomical sites within the calvarium as well as the skull itself. The authors present a hydatid cyst that was localized in the proximal third of the aqueduct of Sylvius producing increased intracranial pressure by obliteration of the aqueduct. Preoperative diagnosis was made by computerized tomography and the cyst was removed by a posterior fossa approach.