The need for medical images which can directly contribute to therapeutic decision making has led to the development of 3D visualization techniques. With this objective, a procedure capable of producing 3D volume reconstructions using isotropic voxels from digitalized 2D films obtained by rotation around the object has been developed: 3D morphometry. The technique has been assessed from 1993 through 1996 for vascular malformations in the brain, particularly aneurysms. Recognition of collateral vessels originating at the malformation was helpful in better identifying the lesions and evaluating possible therapeutic difficulties. The morphometric sequence thus is a possibility for the future assessment of neurovascular arches.