Carotid back pressures in conjunction with cerebral angiography.

A method for obtaining carotid back pressures at the time of cerebral angiography is described. These preoperative measurements were compared to intraoperative measurements in 18 patients. Preoperative mean carotid back pressures (usually common carotid pressures) were obtained by occluding the artery with a double-lumen balloon catheter and recording the pressure distal to the balloon. Although the mean arterial blood pressure and the arterial carbon dioxide tension proved to be variables, the correlation of the pressures measured at angiography and at surgery was high (p less than 0.001).