What is the definitive difference between a davf or an avm?

I understand that davf stands for dural arteriovenous fistula, and avm stands for arteriovenous malformation, and the MRI’s for both look so similar, I really want to understand what the difference is?

burygold: An arteriovenous fistula (AVF) is a direct connection between an artery and a vein. The blood bypasses the capillaries and tissues, and returns to the heart. Arterial blood has a higher blood pressure than veins and causes swelling of veins involved in a fistula. AVF’s are similar to AVM’s in that they both disrupt the circulatory cycle.

An AVF is characterized by a single connection between and artery and a vein, whereas an AVM contains multiple arteries and veins.

There are two types of arteriovenous fistulas, congenital and acquired.

A congenital arteriovenous fistula is a rare birth defect that formed during fetal development.

An acquired arteriovenous fistula is one that develops after a person is born. It usually occurs when an artery and vein that are side-by-side are damaged, and the healing process results in the two becoming linked. For example, after catheterizations, arteriovenous fistulas may occur as a complication of the arterial puncture in the leg or arm.

Fistulas also form without obvious cause.

The cause of AVM is unknown but science believe it is congenital, developed during very early fetal development (5-6 week) or in some rare cases the cause of AVM might be genetic (HHT).

Hope this helped to clarify the difference…

Positive thoughts from Hanne xxx

Thank you Hanne. Very well said :o).