Familial unusual encephalopathy of Binswanger's type without hypertension.

Clinical and pathological studies have been conducted on two brothers with unusual encephalopathy of Binswanger's type. The disease started in the third decade with steady progressive course leading to death in eight or nine years. The clinical picture was summarized as a combination of organic dementia, extrapyramidal disorders associated with pseudobulbar symptoms and marked pyramidal tract signs. The blood pressure remained always normal during the course. Pathologically, there were diffuse and focal demyelination with sparing of U-fibers, multiple small foci of perivascular softening in the cerebral white matter and in the basal ganglia and severe arteriosclerotic changes of memingeal small arteries and long arteries with 100 to 400 micron caliber in the cerebral white matter. Vessel changes consisted of fibrous intimal proliferation, severe hyalinosis and splitting of intima and/or internal elastic membrane. The histopathological process belonged to the category of subcortical arteriosclerotic encephalopathy of Binswanger's type. There has been some discussion as to differential diagnosis among various forms of vasculitis such as cerebral endangiitis obliterans, periarteritis nodosa, systemic lupus erythematosus, rheumatic vascular disease and giant cell arteritis.