Cerebrovascular applications of magnetic resonance angiography

Magnetic resonance angiography (MRA) has been applied to a variety of different manifestations of cerebrovascular disease to date. Practically, the limitations of these techniques must be taken into account such that the appropriate method is applied to answer a specific clinical question and the acquisition parameters are chosen to maximise the sensitivity and specificity of the study. Based upon these results, it must be decided whether the conventional parenchymal MR and MRA evaluations are sufficient in a particular setting or whether it is necessary to commit the patient to a more traditional, invasive angiographic study for a more thorough investigation. Presently, MR angiographic studies and flow measurement techniques serve to compliment the more traditional spin-echo evaluation of patients with small aneurysms, arterial and venous occlusions, vascular malformations and in some cases of neoplastic vascular invasion. With well-trained technicians and carefully prescribed protocols, this new information and improved diagnostic sensitivity can be used routinely with only a minor increase in patient exam time.