We report MRI findings in a family with an autosomal-dominant, adult-o
nset neurological disorder. The clinical picture, the white matter cha
nges detected on MRI and the absence of any laboratory abnormality sug
gested the diagnosis of leukodystrophy with an unknown biochemical def
ect. Autosomal-dominant inheritance is extremely rare in this kind of
disease, and most reported families have not undergone MRI. We perform
ed MRI and clinical examination of 17 members of our family; 9 affecte
d subjects, at different stages of the disease, were detected. The mos
t characteristic MRI findings were initially symmetrical areas of sign
al change in the white matter of the trigonal region; demyelination ex
tending thereafter to the frontal and parietal regions, partially invo
lving subcortical white matter; the temporal lobe and optic radiations
were less involved; the internal capsule and corpus callosum were inv
olved later, in a dorsoventral direction; patchy demyelination was evi
dent in the late stages in the brain stem; the cerebellum was spared e
ven in the latest stages of the disease. While pathological examinatio
n is essential to characterise and classify these kinds of diseases, M
RI can make substantial contributions to understanding their natural h
istory, and to detect early signs of the disease.