Acute myelopathy. Retrospective clinical, laboratory, MRI and outcome analysis of 49 cases

A comparison between spinal cord infarction and neuromyelitis optica spectrum disorders: Clinical and MRI studies

This study aims to investigate the clinical features and magnetic resonance imaging (MRI) findings in patients with spinal cord infarction (SCI) and neuromyelitis optica spectrum disorders (NMOSDs). Over a period of 16 years, we retrospectively analyzed 39 patients with SCI and 21 patients with NMOSD. The demographic features and clinical presentations of both diseases were carefully documented. Etiology-specific MRI features, such as the length and distribution of the lesions, the owl's eyes sign and bright spotty lesions, were recorded and analyzed regarding their association with the clinical signs/symptoms. Patients with SCI were older than patients with NMOSD and had sudden onset of clinical symptoms with focal pain adjacent to the lesions. Concomitant spinal cord and vertebral body infarctions were frequently associated with aortic pathology (p = 0.04). In addition, artery dissection was highly associated with combined ASA and unilateral PSA infarctions and long segments of SCI (all p < 0.05). In contrast, patients with NMOSD had a relatively younger age of onset, female predominance and subacute progression of limbs weakness. As observed by MRI, the length and location of the lesions demonstrated significant differences between the two diseases (P < 0.01). The owl's eyes sign showed more frequently in patients with SCI than NMOSD (p < 0.01). The predicted prognoses in SCI and NMOSD were significantly associated with initial motor function (muscle power), after adjustments for age and gender (p < 0.01 and p = 0.02, respectively). Along with patient demographic characteristics, lesion features on MRI can help clinicians differentiate acute noncompressive myelopathy due to SCI from that due to NMOSD, which may lead to immediate initiation of adequate therapeutic measures.

Acute spinal-cord ischemia: evolution of MRI findings

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.

[Imaging of non-traumatic and non-tumoral cord lesions]

There is a wide range of spinal cord pathologies (vascular, inflammatory, infectious, metabolic, degenerative). They present clinically as acute partial or complete cord syndromes, or chronic myelopathies (more than 4 weeks in duration). MRI examination should be undertaken with a very strict protocol. Spinal cord lesions should be evaluated with regards to their T1W and T2W signal characteristics, involvement of grey and/or white matter, axial and sagittal extension, cord volume changes, contrast uptake and associated lesions (perimedullary, radicular or brain). The correlation of MR imaging features with clinical and biological data (blood and CSF) should suggest a differential diagnosis.

Acute myelopathy of unknown aetiology: a follow-up investigation

Acute myelopathy refers to acute or subacute spinal cord dysfunction secondary to various causes. Recent studies suggest a number of distinct clinical, laboratory, MRI and outcome profiles for the various aetiologies. Nevertheless, the aetiology of acute myelopathy remains unknown in up to 60% of the patients. The probability of establishing the correct diagnosis increases with the duration of clinical and MRI follow-up. This paper presents the results of a follow-up of nine cases of acute myelopathy of unknown aetiology. One patient was lost during follow-up. Mean age of patients at the time of the follow-up interview was 48 years (+/-12). Average time from discharge to follow-up interview was 3.6 (+/-0.5) years. In four patients (mean age 45+/-13 years) the origin of acute myelopathy remained unclear after an average follow-up of 3.3 years. In one patient the diagnosis of multiple sclerosis was established during follow-up. In another patient the clinical course was suggestive for multiple sclerosis. One patient was diagnosed with systemic collagen vascular disease and in one patient a diagnosis of non-Hodgkin's lymphoma was established. It is unclear whether the patients in whom the aetiology of acute myelopathy remained unknown, even after several years of follow-up, are at a higher risk of developing progressive disease. Larger studies with longer follow-up periods and clear clinical, laboratory and MRI criteria should help to shed some light on this issue.