Pearls: Myelopathy

ABSTRACT

Both general neurologists and neurologists with a broad spectrum of subspecialty interests are often asked to evaluate patients with disorders of the spinal cord. Over the past decade, there have been significant advances in our understanding of a wide spectrum of immune-mediated, infectious, metabolic, hereditary, paraneoplastic, and compressive myelopathies. Advances have been made in the classification and management of spinal vascular malformations. Aortic reconstruction surgery has led to an increased incidence of spinal cord stroke. It is important to recognize a dural arteriovenous fistula as a cause of progressive myelopathy. In the past, noninfectious inflammatory myelopathies have frequently been categorized as idiopathic transverse myelitis. Advances in neuroimaging and discovery of a serum antibody marker, neuromyelitis optica-immunoglobulin G (NMO-IgG), have allowed more specific diagnoses, such as multiple sclerosis and neuromyelitis optica. Abnormalities suggestive of demyelinating disease on brain magnetic resonance imaging (MRI) are known to be highly predictive of conversion to multiple sclerosis in a patient who presents with a transverse myelitis (“clinically isolated syndrome”). Acquired copper deficiency can cause a clinical picture that mimics the subacute combined degeneration seen with vitamin B₁₂ deficiency. A history of bariatric surgery is commonly noted in patients with copper deficiency myelopathy. Genetics has advanced our understanding of the complex field of hereditary myelopathies. Three hereditary myelopathy phenotypes are recognized: predominantly cerebellar (e.g., Friedreich’s ataxia), predominantly motor (e.g., hereditary spastic paraparesis), and a leukodystrophy phenotype (e.g., adrenomyeloneuropathy). Evaluation of myelopathies when no abnormalities are seen on spinal cord imaging is a commonly encountered diagnostic challenge. This article presents some “clinical pearls” in the evaluation and management of spinal cord diseases in context of these recent developments.

KEYWORDS

Myelopathies - vascular - inflammatory - metabolic - hereditary - compressive

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