Unique enlarging cavernous malformation secondary to abnormal arteriovenous shunting through an associated developmental venous anomaly.

Cavernous malformations are angiographically occult vascular malformations. They are often associated with a developmental venous anomaly through poorly understood mechanisms. We present an unusual case of a gradually enlarging cavernous malformation associated with a developmental venous anomaly with arteriovenous shunting, suggesting venous hypertension or reflux as a potential cause of progressive growth.