BD was diagnosed by clinical examination, electroencephalogram (EEG), Transcranial Doppler (TCD) and multislice CT of 64 detectors. Initially, a brain perfusion study was performed. This was followed by supra-aortic trunk and brain artery angiography with acquisition of images using 0.5 mm slices, from the origin of the aortic root to the vertex. In all the patients, BD diagnosis was verified by clinical examination, EEG and TCD. Brain perfusion never detected brain blood flow. The angioCT through internal carotid arteries and vertebral arteries demonstrated complete absence of intracranial circulation, observing circulation of the external carotid artery branches. Sensitivity and specificity of the method compared with clinical examination was 100%. These findings demonstrate that the study of brain perfusion and brain angiography by multislice CT scan is a rapid and minimally invasive technique, that is easily available and that shows the absence of brain blood flow through the four vascular trunks. This technique makes it possible to made the diagnosis of BD with high diagnostic safety. Its use has special interest in patients with clinical diagnostic difficulty due to treatment with sedative drugs and serious metabolic alterations.