Spontaneous spinal subarachnoid hemorrhage secondary to spinal aneurysms: diagnosis and treatment paradigm.

INTRODUCTION: Isolated spinal aneurysms are rare; only a few have been reported. To the best of our knowledge, this series represents the largest experience with four ruptured spinal aneurysms, all of which were treated surgically.
METHODS: Clinical information from the hospital charts and diagnostic images of four patients with the diagnosis of spinal aneurysms were reviewed from the senior authors' (RFS, JMZ) office database, surgical reports, and radiological imaging database. Follow-up examinations were performed by phone interview, when possible, and by chart review.
RESULTS: Between 1997 and 2004, four patients with ruptured spinal aneurysms underwent surgical treatment. All aneurysms were located within the spinal canal and manifested with spinal subarachnoid hemorrhage. No collagen disease, aortic coartaction, arteriovenous fistula, or arteriovenous malformations were identified in these patients.
CONCLUSION: Subarachnoid hemorrhage within the spinal cord can be caused by ruptured aneurysms. Spinal aneurysms are rare, but should be considered within the differential diagnosis of patients with intracranial subarachnoid hemorrhage when cranial angiography is negative. Magnetic resonance imaging and selective spinal angiography are useful for workup, but definitive diagnosis may require surgical exploration.