Early diagnosis of spinal cord infarct using magnetic resonance diffusion imaging

Abstract

Acute paraplegia can result from spinal cord compression, inflammation, tumor, infection, or ischemia. 1 The poor prognosis of spinal cord lesions is often related to treatment delay, so that early diagnosis is essential. The current practice in acute spinal cord symptoms is to do an emergency MRI in search of a surgically treatable spinal cord compression. 1 However, in case of acute infarct, T1-weighted and T2-weighted images are often normal as they are in cerebral infarction. Diffusion-weighted imaging (DWI) is the best sequence to reveal early brain infarction. The availability of this technique in the spinal cord has been limited. We report an example of the usefulness of DWI for diagnosing acute spinal cord infarct.Case report. A 68-year-old man, without past medical history, was admitted to our hospital 4 hours after the sudden onset of paraplegia associated with back pain, lower limb dysesthesias, and urinary retention. The patient had no known vascular risk factors. There were flaccid paraplegia with areflexia of the legs, a bilateral Babinski sign, and hypoesthesia to pain and temperature at the L2 to L3 level. MRI with T1-weighted and T2-weighted images and DWI were performed 7 hours after the onset of symptoms. T1-weighted and T2-weighted images were normal (figure, A). DWI showed a high intensity signal at the anterior part of the lumbar spinal cord and the conus medullaris (see the figure, B). Apparent diffusion coefficient (ADC) map showed a decrease in water self-diffusion in that area. The topography was consistent with the anterior spinal cord artery territory. Based on the clinical and the DWI findings, we diagnosed a spinal cord infarct. A second MR examination performed 34 hours after the clinical onset showed, on T2-weighted imaging (see the figure, C), the presence of a high signal intensity at the site of abnormalities seen on DWI, thus confirming the diagnosis of spinal cord infarct. Serum and CSF biological values were normal as well as cardiovascular investigations. After 1 year, there was a slight improvement of the paraplegia with a Medical Research Council motor score at 3 of 5, without improvement of the sensory abnormalities.Discussion. MRI is useful in acute spinal cord symptoms. 1 Four clinical-pathologic manifestations of medullary ischemia have been described: infarction from occlusion of the anterior spinal artery, "patchy" or "lacunar infarction," "transverse ischemic infarction," and selective ischemia in the regions of the posterior spinal arteries. 2 However, with use of conventional MRI sequences, ischemic lesions appear only 10 to 15 hours after the onset. Moreover, acute cerebral stroke can be diagnosed as early as a few minutes after clinical onset using DWI, whereas other imaging modalities such as CT, T1weighted MRI, and T2-weighted MRI are still normal. 3 A few studies have demonstrated the DWI potential in the depiction of spinal cord pathologies. 4 The major limitations for spinal cord DWI in vivo are the artifacts induced by surrounding tissues, including those ...

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Diffusion MRI in spinal dural arterio-venous fistula: a case report

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“…4 Several groups recently reported the usefulness of diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) maps to reveal early spinal cord infarction. [5][6][7] The use of ADC maps may help to differentiate vasogenic from cytotoxic oedema in the spinal cord. We illustrate the usefulness of DWI and ADC maps for diagnosing and predicting the prognosis of a reversible acute myelopathy due to vasogenic oedema accompanying a SDAVF.…”

Medullar Infarcts of the Posterior Cervical Spinal Area: About an Observation in the Neurology Department of the University Hospital of Cocody, Abidjan, Ivory Coast

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