• Main Diseases dictionary Nervous system

Arteriovenous aneurysm, or arteriovenous fistula

Is any abnormal communication established between the arterial and venous channels. It includes, therefore, all direct and indirect communications variously spoken of as arteriovenous varix, varicose aneurysm, aneurysm by anastomosis, pulsating venous aneurysm and cirsoid aneurysm. These communications usually result from trauma to the vessels, such as piercing, incisive, lacerating, crushing or contusive wounds (cirsoid aneurysm of scalp is a notable example), and are known as acquired arteriovenous aneurysms; not infrequently they are produced by developmental anomalies, and are then termed congenital.