Spinal Cord Infarction¶
Definition¶
Spinal cord infarction results from interruption of the arterial blood supply to the spinal cord, causing acute ischemia and neurological deficit. It is much less common than cerebral infarction due to the rich collateral blood supply of the cord, but when it occurs, it produces devastating and often irreversible neurological injury.
Etiology¶
- Aortic surgery — The most common cause (particularly thoracoabdominal aortic aneurysm repair), due to interruption of segmental arteries that supply the cord
- Aortic pathology — Dissection, thrombosis, atherosclerosis
- Hypotension — Systemic hypoperfusion (cardiac arrest, shock)
- Vertebral artery dissection — May cause posterior cord infarction
- Embolic — Fibrocartilaginous embolism from disc material (rare but recognized)
- Vasculitis — SLE, PAN
- Venous infarction — From dural AVF or venous thrombosis
Imaging Findings¶
MRI¶
- DWI — Restricted diffusion in the cord is the earliest and most sensitive finding (similar to brain infarction)
- T2-weighted — High signal within the cord in the affected vascular territory. In anterior spinal artery infarction, the T2 hyperintensity involves the anterior two-thirds of the cord.
- "Owl eyes" or "snake eyes" sign — On axial T2 images, bilateral symmetric hyperintensity in the anterior horns (gray matter), resembling owl eyes. This is highly characteristic of anterior spinal artery infarction.
- Cord expansion — Mild swelling in the acute phase
- Enhancement — May develop in the subacute phase
- Vertebral body infarction — Concurrent vertebral body marrow edema may be present because the segmental arteries supply both the cord and the vertebral body
CT¶
- Usually normal in the acute phase
- CT angiography may identify the underlying vascular cause (aortic dissection, thrombosis)
Clinical Pearl
The "owl eyes" sign — bilateral symmetric T2 hyperintensity in the anterior horns on axial MRI — is highly characteristic of anterior spinal artery infarction. Concurrent vertebral body marrow edema on STIR at the same level further supports the diagnosis, as the segmental arteries supply both the cord and the vertebral body. DWI showing restricted diffusion in the cord is the earliest finding, just as in brain infarction.
Key Points¶
- Most commonly caused by aortic surgery or aortic pathology
- DWI restricted diffusion is the earliest MRI finding
- "Owl eyes" sign on axial T2 is characteristic of anterior spinal artery infarction
- Concurrent vertebral body infarction supports the diagnosis
- Anterior spinal artery territory (anterior 2/3 of cord) is most commonly affected
- Prognosis is variable — some recovery possible but often significant residual deficits
References¶
- Hanna Al-Shaikh R, Czervionke L, Eidelman B, Dredla BK. Spinal Cord Infarction. In: StatPearls. Treasure Island (FL): StatPearls Publishing; updated 2023 Aug 14. https://www.ncbi.nlm.nih.gov/books/NBK545185/
- Acute spinal cord ischaemia syndrome. Radiopaedia.org. https://radiopaedia.org/articles/acute-spinal-cord-ischaemia-syndrome
- Vargas MI, Gariani J, Sztajzel R, et al. Spinal Cord Ischemia: Practical Imaging Tips, Pearls, and Pitfalls. AJNR Am J Neuroradiol. 2015;36(5):825-830. https://pmc.ncbi.nlm.nih.gov/articles/PMC7990611/
- Masson C, Pruvo JP, Meder JF, et al. Spinal cord infarction: clinical and magnetic resonance imaging findings and short term outcome. J Neurol Neurosurg Psychiatry. 2004;75(10):1431-1435. https://pubmed.ncbi.nlm.nih.gov/15377691/
- Thurnher MM, Bammer R. Diffusion-weighted MR imaging (DWI) in spinal cord ischemia. Neuroradiology. 2006;48(11):795-801. https://pubmed.ncbi.nlm.nih.gov/16977443/
- Expert Panel on Neurological Imaging; Agarwal V, Shah LM, Parsons MS, et al. ACR Appropriateness Criteria® Myelopathy: 2021 Update. J Am Coll Radiol. 2021;18(5S):S73-S82. https://pubmed.ncbi.nlm.nih.gov/33958120/