Arteriovenous Malformation (AVM) can be diagnosed on a computed tomography (CT) or magnetic resonance imaging (MRI) scan.
They may be diagnosed incidentally or after hemorrhage.
After detection of an Arteriovenous Malformation (AVM), further evaluation needs to be carried out by cerebral angiography. This will give further information regarding the structure of the AVM, the contributing and drainage vessels which will influence treatment decisions.
AVMs are graded by the Spetzler-Martin grading system. This is based on points allocated based on the size, location and pattern of blood flow of the AVM.
The grading ranges from 1 to 5. The higher the grading, the greater the difficulty of treatment.