Central pontine myelinolysis

Central pontine myelinolysis is a disease process described by Adams, Victor, and Mancall in 1959 in which there is destruction of the myelin sheaths in the basis pontis in a central well demarcated symmetric area. The origin of this lesion defies any single simple explanation since it appears to have some association with malnutrition, alcoholism, or severe debilitation from concurrent illness. Microscopically, within the area of the lesion, nearly all myelin sheaths are destroyed. Despite the extensive demyelination, axis cylinders and neurons are remarkably intact unless the lesion progresses to central cavitation. However, there is essentially complete absence of oligodendrogliocytes, which suggests perhaps a selective vulnerability of this cellular element. While it has been noted that midline symmetric demyelinating lesions are also seen in Marchiafava Bignami disease, no cases of concomitant pontine myelinolysis and Marchiafava Bignami disease have been reported. A case of central pontine myelinolysis is presented (man of 41) which was associated with alcoholism, delirium tremens, an episode of hypoxia, renal disease, and minimal pathologic change of the liver. Autopsy showed in the central part of the basis pontis an area of softening with indistinct margins. Histologic sections showed diffuse demyelination with preservation of neurons but not axis cylinders. Macrophages were particularly abundant in some areas. There was no pigment or hemorrhage, and blood vessels appeared unremarkable. The demyelinated area was well demarcated from the surrounding intact portion of pons but with an irregular border. Sections of cerebral and cerebellar cortex showed severe anoxic changes several weeks old.