Unusual mesencephalic developmental venous anomaly causing obstructive hydrocephalus due to aqueductal stenosis.

[hydrocephalus with stenosis of the aqueduct of sylvius]

Developmental venous anomalies (DVAs ) are benign vascular malformations that rarely become symptomatic . They are anatomical variations of the venous drainage system and most are incidentally discovered . Mechanical (obstruction and compression of cerebral and neural structures ) and flow-related pathological mechanisms have been described in rare cases of symptomatic DVAs . The authors present the case of a 10 -month -old boy with a mesencephalic DVA compressing the aqueduct and causing occlusive hydrocephalus . Endoscopic inspection confirmed the venous malformation causing aqueductal stenosis . The authors successfully performed endoscopic third ventriculostomy , resulting in decrease in the size of the ventricles . At the 6 -month follow-up after surgery , the patient had significantly progressed in his psychomotor development . One year postsurgery the patient is doing fine , with no neurological or developmental deficits .