Intra-aneurysmal pressure difference in human saccular aneurysms.

Intra-aneurysmal pressure and piezometric head differences with respect to common carotid values have been recorded by unidirectional and differential transducers in two patients undergoing craniotomy for aneurysms of the anterior communicating and middle cerebral arteries. Recordings were taken under normal systemic arterial pressure during temporary occlusion of the common carotid artery, during intra operative carotid arteriography and under controlled arterial hypotension. Predominance of the common carotid pressure head and piezometric head over the aneurysmal value was found in the two cases.