Symptomatic Infratentorial Thrombosed Developmental Venous Anomaly: Case Report and Review of the Literature

Background: Developmental venous anomalies (DVAs) are variations of normal transmedullary veins draining white and gray matter. In the vast majority of cases, DVAs are diagnosed incidentally and should be considered as benign entities. In extremely rare circumstances, DVAs may become symptomatic due to mechanical or flow-related etiologies. Thrombosis of the collector vein of a DVA is a rare type of a flow-related complication with only 29 cases reported in the literature, the majority of which are supratentorial. Infratentorial thrombosed DVAs are thus extremely rare and the few cases reported have typically caused symptoms due to venous ischemic infarctions. Summary: We report a case of an infratentorial DVA with a thrombosed drainage vein in a patient with nonhemorrhagic, noninfarcted venous congestive edema, which was successfully treated with high-dose glucocorticoids and short-term anticoagulation. We review the pertinent venous anatomy of the posterior fossa as well as the literature of symptomatic infratentorial thrombosed DVAs. Key Message: The presented case of an infratentorial thrombosed DVA with cerebellar and pontine venous congestive edema is extremely rare. A working knowledge of posterior fossa venous anatomy and possible pathomechanisms responsible for the rarely symptomatic lesion will aid in the timely and efficacious treatment of such lesions.