Osmotic demyelination syndrome. Lack of pathologic and radiologic imaging correlation
D. B. Clifford, M. H. Gado and B. K. Levy
Department of Neurology and Neurological Surgery, Washington University School of Medicine, St. Louis, MO 63110.
An otherwise healthy diabetic woman developed severe hyponatremia, her
serum sodium ion levels were rapidly corrected to normal, and she had a
course of improvement then neurologic deterioration, with seizures and coma
developing in the subsequent two days. Imaging studies, including computed
tomography and magnetic resonance images of the brain as late as 19 days
after the osmotic insult, failed to show pathologically demonstrated
demyelinating lesions. Osmotic brain injury induces demyelination in areas
of gray-white apposition and, clinically, results in a delayed neurologic
deterioration one to three days following the osmotic challenge. Even with
magnetic resonance imaging, review of the literature and this experience
suggest that osmotic demyelination cannot reliably be imaged during the
first month after the insult.