Pontine spongy degeneration of white matter associated with hepatic encephalopathy.

Spongy degeneration of white matter localized to basis pontis was found in a 47-year-old woman with hepatic encephalopathy. In this clinical setting, the lesion resembled those changes described by Victor et al and found primarily in cerebral cortex, subcortical white matter, and putamen. Isolated involvement of the basis pontis and ventral midline tegmentum of pons has not, to our knowledge, been previously reported. The morphologic appearance and distribution distinguish this lesion from central pontine myelinolysis. The possible vascular cause of this localized interstitial edema is discussed.