Predicting spinal cord ischemia before endovascular thoracoabdominal aneurysm repair: monitoring somatosensory evoked potentials.

PURPOSE: To present a method of predicting spinal cord ischemia before deployment of an endograft in the thoracoabdominal aorta. CASE REPORT: A 76-year-old high-risk patient presented with an aneurysm of the distal thoracic and proximal abdominal aorta. An endovascular treatment was scheduled, but before deployment of the endograft, occlusion of the aneurysmal segment was monitored for 15 minutes using multilevel somatosensory evoked potentials (SEP). An external axillofemoral bypass was necessary during the test period to prevent distal ischemia; transesophageal echocardiography verified the absence of flow inside the aneurysm during occlusion. Because no SEP changes occurred during the 15-minute test, a 20-cm-long endograft was deployed. No postoperative neurological event was encountered, and the aneurysm has remained successfully excluded with shrinkage of the sac diameter by 1 cm at 6 months. CONCLUSIONS: An occlusion test to detect spinal cord ischemia before deployment of an endograft could be useful in lowering the risk of paraplegia associated with endovascular treatment of thoracoabdominal aneurysm.