PET in Brain Arteriovenous Malformations and Cerebral Proliferative Angiopathy

A brain arteriovenous malformation (BAVM) is a neurovascular entity that consists of a localized dense network of abnormal blood vessels (a nidus) that holds arteries shunting directly into veins in the absence of a capillary bed. In their natural history, BAVMs carry a risk of hemorrhage or other neurological complications, for which reason they are frequently treated. Cerebral proliferative angiopathy (CPA) is a different type of neurovascular malformation with distinct angiographic and clinical features that can be used to differentiate it from a classical BAVM. The basic difference between CPA and a BAVM is that CPA has normal brain tissue intermingled in between its network of vessels. Treatment of CPA by surgery, radiosurgery, or embolization consequently harbors a high risk of neurological complications. As such, reliable diagnostic discrimination between CPA and BAVM is crucial to adequately treat patients. However, despite the fact that CPA has some characteristic imaging features, the differentiation between CPA and a brain AVM may be difficult. PET imaging as a technique that reveals functional brain tissue is therefore likely to be of additional diagnostic value.