**7. Diagnosis**

Imaging studies are essential for the establishment of the diagnosis of cAVM, to make a pre-therapeutic evaluation of the cAVM to help in decision-making, to treat the AVM as a sole therapy or a multidisciplinary approach. It also helps in posttherapeutic evaluation of cAVM.

### **7.1 Computerized tomography (CT) of the brain**

The CT of the brain is the first imaging procedure used to rule out hemorrhage. cAVM is suspected in young patients with lobar hematoma without significant oedema and calcifications. The parenchymal calcifications are found in 20% of cases, related to intravascular thrombosis or evolution of an old hematoma.

**Figure 4.** *Cerebral angiogram showing cAVM.*

The compression of the nidus by hematoma precludes CT diagnosis of cAVM in patients with acute intracerebral hemorrhage; in these patients CT angiography and magnetic resonance angiography are essential.
