Detection and Analysis of Cranial Bruit

A method of detecting cranial bruits produced by turbulent blood circulation in the head is presented. The acoustic properties of the head were examined in order to design and evaluate a direct-contact-type phonodetector using an accelerometer. The detection apparatus described here can be applied to any part of the head and is able to detect weak bruits over the frequency range of 100 Hz-3 kHz. It has fairly simple frequency characteristics. Spectral and coherence analyses made on bruits recorded by the detection apparatus indicated the possibility of noninvasive diagnosis of intracranial vascular lesions, especially for detecting aneurysm in mass examinations.