INTRAOPERATIVE RECORDING OF PARIETAL SEP CAN MISS HEMODYNAMIC INFARCTION DURING CAROTID ENDARTERECTOMY - A CASE-STUDY

Serial recording of median nerve somatosensory evoked potentials (SEPs ) provides reliable intraoperative information on critical lowering of brain perfusion which compares favorably with other monitoring method s. However, single-channel parietal SEP recording may not detect hemod ynamic cerebral infarctions affecting the pre-rolandic area. Following left carotid endarterectomy for high-grade symptomatic stenosis in a 66-year-old male, predominantly motor hemiparesis and aphasia were det ected which were largely reversible. Pre- and intraoperative SEPs were normal. Postoperative SEPs showed significant interhemispheric amplit ude differences. Postoperative CT examinations demonstrated hemodynami c watershed-type infarctions. This rare complication of carotid endart erectomy was not detected by intraoperative single-channel parietal SE P monitoring.