[A surgical case of tectal cavernous malformation presented by hydrocephalus].

We report a surgical case of tectal cavernous malformation presented by hydrocephalus. This 30-year-old man suffered from headache and nausea due to an obstructive hydrocephalus caused by a cavernous malformation in the tectum. Magnetic resonance (MR) images on admission showed a small lesion depicted as isointensity on the T1-weighted image, hyperintensity on the T2-weighted image, and accompanied with peripheral low-signal intensity rim, suggesting a tectal cavernous malformation. After admission, ventricular drainage was performed and the patient's symptoms improved immediately. He underwent a ventriculoperitoneal shunt ten days after the ventricular drainage. Postoperative CT scan showed an enlargement of the tectal mass with hemorrhagic change, but there was no deterioration in his neurological status. Cerebral angiography demonstrated no vascular stain or venous malformation. Microsurgical removal of the tectal mass was then performed via an occipital transtentorial approach. Histopathology proved a cavernous malformation and MR images at follow-up demonstrated total excision. Postoperatively, an upward gaze palsy appeared, but gradually improved within a month. Management strategy of brain stem cavernous malformation is controversial. Occasionally, brain stem hemorrhage may become critical. Therefore, we recommend aggressive surgical extirpation of symptomatic brain stem cavernous malformation, if it is accessible, if hemorrhage is present, and if the patient's condition permits it.