Acute spinal-cord ischemia: evolution of MRI findings

Abstract

Background and purpose: Magnetic resonance (MR) findings in acute spinal-cord ischemia can be summarized as focal cord enlargement and hyperintensities on T2-weighted images and gadolinium enhancement, especially of the central gray matter. However, in analogy with acute brain ischemia, it is to be expected that the findings of MR imaging (MRI) may be normal in the first hours after symptom onset. We evaluated the clinical and MRI findings in a series of patients with acute spinal-cord ischemia, and tested the hypothesis that the development and course of MR abnormalities are predictable.

Methods: Five patients with acute spinal-cord ischemia were admitted to our hospital over a 2-year period. Repeated MRI (1.5 T) was performed in all patients. Clinical data were retrieved from the patients' charts.

Results: Four women and one man with a median age of 52 years (range, 31-75 years) were admitted. Three patients had anterior spinal artery infarction and two patients had transverse infarctions. All patients underwent spinal MRI within 24 hours; the findings were normal in four of the five patients. After 1-2 days, T2-weighted MRI generally exhibited focal cord enlargement and hyperintensity in all patients, while spinal-cord enhancement appeared after 2-11 days.

Conclusions: Acute spinal-cord ischemia may have a typical course on MRI. MRI findings are usually normal in the acute phase, but spinal cord swelling and T2 abnormality are expected after several days, while gadolinium enhancement appears even later after symptom onset. The sensitivity and specificity of MRI can be increased by repeated MRI in patients suspected of acute spinal-cord ischemia.

Keywords: MRI; course; spinal-cord ischemia.

Fig. 1

A: MRI performed 12 hours after symptom onset: 31-year-old female presenting with right-sided Horner syndrome and right-sided loss of strength. Sagittal T2-weighted image showing no cord abnormalities. B: MRI performed 12 hours after symptom onset: axial T1-weighted image with fat suppression showing an abnormally high signal intensity (SI) in most of the cross-sectional area of the right vertebral artery, with a small central flow void (arrow), confirming suspected vertebral artery dissection. C and D: MRI performed 6 days after symptom onset: sagittal (C) and axial (D) T2-weighted images showing abnormal areas of high SI on the right at the C2 level. E and F: MRI performed 6 days after symptom onset: axial (E) and sagittal (F) T1-weighted images after administration of gadolinium, revealing enhancement of the cord at the C2 level. G and H: MRI performed 6 days after symptom onset: axial (G) DWI showing right-sided high signal at the C2 level and axial (H) low apparent diffusion coefficient values showing diffusion restriction, supporting the diagnosis of spinal-cord ischemia. DWI: diffusion-weighted imaging, MRI: magnetic resonance imaging.