Atheromatous emboli to the lumbosacral spinal cord.

The lumbosacral spinal cords of 28 patients with atheromatous emboli to abdominal viscera and/or grafts to the abdominal aorta were examined by serial sections. In 12 patients, atheromatous emboli were found in spinal arteries, most commonly in the sacral cord, and most frequently in the anterior spinal artery. The general absence of spinal cord infarctions was attributed to the nature of the emboli, apparent good collateral circulation, and the absence of diffuse atherosclerosis. However, 38% of the patients had arteriosclerosis; this was generally focal and not associated with significant luminal narrowing. Only one patient had infarction, which was limited primarily to the gray matter. It would appear that hypoperfusion must exist in conjunction with atheromatous emboli in order for infarction to develop. Organized atheromatous emboli also caused focal ischemic atrophy of neurons. It is postulated that this change may be the morphological basis for some of the atypical lower motor neuron diseases found in the elderly.