[A case of aortic coarctation presenting with Brown-Séquard syndrome due to radicular artery aneurysm].

We report a case of aortic coarctation who showed a Brown-Séquard syndrome due to the aneurysm of the anterior radicular artery. A 71-year-old right-handed hypertensive woman was admitted to the Research Institute for Brain and Blood Vessels because of subarachnoid hemorrhage in 1984. No aneurysm was detected even on the four-vessel cerebral angiography. However, the left subclavian artery was occluded associated with the coarctation. In 1997, she complained of numbness of the right lower extremity, which gradually expanded to the back and the right upper extremity. On neurological examination, she exhibited a mild weakness of the right lower extremity and a dissociated sensory disturbance below the level of C5. The cervical MRI showed a space occupying lesion at the level of C4. The right vertebral angiography revealed an aneurysm of the left anterior radicular artery at the level of C4, which compressed the spinal cord. Previously only a few cases of an aortic coarctation associated with the radicular artery aneurysm were reported in our country. The age of onset of this case was older than in the previous cases, and the location of the aneurysm was higher than those of the previous cases. Probably due to the occlusion of the left subclavian artery, the transverse collateral circulation was produced from the right to the left anterior radicular arteries at the level between C2 and C5, causing a radicular artery aneurysm in this patient.