[Acute spongiform leucoencephalopathy with selective intramyelinic involvement of U fibers associated with an ovarian carcinoma. Syndrome of disconnection of U fibers (author's transl)].

Case report of clinical, pathological and ultrastructural features in an acute spongiform leucoencephalopathy with selective involvement of U fibers. A 52 years old woman exhibited an acute encephalopathy of 2 months duration, with dementia and multifocal impairment of cortical functions. The cerebral cortex was normal. This acute dementia resulted from a diffuse intercortical disconnection. Spongy degeneration was only found in U fibers. No other changes were noted especially in basal ganglia, optics tracts, and spinal cord. The white matter status spongious was related to an intramyelinic oedema. Such intramyelinic oedema is known only in Van Bogaert and Bertrand and Canavan disease, which is quite different, and in toxic encephalopathies, especially those induced by the hexachlorophene and triethyltin. In the present case no drugs or toxins were found. An ovarian carcinoma was found at post-mortem examination.