SPINAL-CORD PROTECTION DURING THORACOABDOMINAL AORTIC-ANEURYSM REPAIR- RESULTS OF SELECTIVE RECONSTRUCTION OF THE CRITICAL SEGMENTAL ARTERIES GUIDED BY EVOKED SPINAL-CORD POTENTIAL MONITORING

Purpose: The purpose of this study is to evaluate the results of spina l cord protection based on selective reconstruction of the segmental a rteries. Methods: Twenty-one patients who underwent repair of aneurysm s (nine descending thoracic and 12 thoracoabdominal: three type I, six type II, and three type III) were analyzed. Ten patients had postdiss ection aneurysms. Operative techniques consisted of evoked spinal cord potential (ESP-dsc) monitoring and femorofemoral bypass in all cases, segmental resection in 12, and mild systemic hypothermia in eight. Ar teries critical for cord blood flow were selectively reconstructed; if ESP-dsc showed change after resection of an aortic segment, arteries originating from this segment were reconstructed. Results: ESP-dsc cha nge was observed in 12 patients. Arteries found to be critical were at the T8-L1 level in all but three cases. Selective reconstruction was performed in 10 of these 12 patients. ESP-dsc change could be reversed before reconstruction in four cases, three by control of back-bleedin g critical arteries. Selective reconstruction resulted in return of ES P-dsc in seven other patients. Spinal cord injury occurred in five pat ients, two of whom did not undergo selective reconstruction. Conclusio n: These results suggest that our current technique allows determinati on of critical arteries but does not completely prevent injury.