Recurrent cryptic vascular malformation associated with a developmental venous anomaly.

Abnormal venous drainage patterns, such as developmental venous anomalies (DVAs), are frequent findings neighbouring cryptic vascular malformations (CVMs). Although the clinical relevance of DVAs remains controversial, increasing attention has been focused on the possible importance of venous outflow disturbance and venous hypertension in DVAs for the development of CVMs. We present the case of a 32-year-old man with dysphasic seizures symptomatic for recurrence and rebleeding of a CVM of the left angulare gyrus, which drained entirely into a large DVA. A cavernoma had been surgically removed 1 year before, while the associated DVA had been left in place. In the following second surgical procedure, the new malformation, which was histologically verified as arteriovenous angioma (AVM), was removed and the DVA was occluded for the length of the angioma. Postoperative course of the patient was unremarkable, the patient is seizure free and neurologically intact. This first report of such a sequence of events raises important questions regarding the association of various vascular malformations, regarding transitional and hybrid forms, as well as the role of anomalous venous drainage in their pathophysiology and probably in their development. Our case and selected cases in literature suggest that venous hypertension in a DVA might not be just a coincidential finding, but sometimes can induce or influence the development and recurrence of associated vascular lesions. The developmental interrelationship, the potential mechanisms for this association and the implications of similar cases reported in pertinent literature are discussed.