THE PATHOGENESIS OF ARTERIOVENOUS-MALFORMATIONS - INSIGHTS PROVIDED BY A CASE OF MULTIPLE ARTERIOVENOUS-MALFORMATIONS DEVELOPING IN RELATION TO A DEVELOPMENTAL VENOUS ANOMALY

OBJECTIVE AND IMPORTANCE: Developmental venous anomalies (DVAs) are co mmon anomalies of intracranial venous drainage that may occur in conju nction with other cerebral vascular malformations. The present case ra ises important questions regarding the association between anomalous v enous drainage patterns and the development of arteriovenous malformat ions (AVMs). CLINICAL PRESENTATION: We present the case of a 24-year-o ld man with small AVMs fed by the superior cerebellar artery that drai ned directly into a large DVA of the cerebellum. INTERVENTION: The pat ient was managed conservatively and returned 10 years later with recur rent symptoms. A repeat angiogram demonstrated spontaneous thrombosis of the previously documented AVMs; however, new AVMs at a different si te that was also fed by the superior cerebellar artery and drained int o the same DVA had appeared. The AVMs were completely embolized, and t he DVA was left intact. CONCLUSION: Recently, increasing attention has focused on the possible importance of venous outflow disturbance and venous hypertension in the pathogenesis and pathophysiology of AVMs. T he potential mechanisms for this association and the implications of t he present case are discussed, and the pertinent literature is reviewe d.