Evaluation of cerebral oximetry during endovascular treatment of carotid-cavernous fistula

Endovascular treatment of carotid cavernous fistula is done routinely in our institution. We have been monitoring these patients with transcranial cerebral oximetry. The transcranial cerebral oximeter is a reliable, low-cost, non-invasive device that provides real-time evaluation of regional brain oxygen saturation during and after endovascular treatment of cerebrovascular diseases. We used the INVOS 3100A (Somanetics, Troy, MI) in our study. We discuss seven patients with carotid-cavernous fistulas treated by endovascular balloon occlusion, each monitored continuously before, during, and after the procedure with transcranial cerebral oximetry. The cerebral oxygen saturation depicted was directly related to the side of the venous drainage of the fistula, with the brain oxygen saturation 15 - 20% higher on the side of the venous drainage. Following endovascular occlusion of the fistula, oxygen saturation gradually became equal on both sides. In our patients treated for carotid-cavernous fistula, we evaluated the sensitivity and usefulness of cerebral oximetry as an important non-invasive monitoring tool for the endovascular treatment of carotid-cavernous fistula.