[A case of slowly progressive unilateral spastic hemiparasis, hand clumsiness, limb ataxia and constructional apraxia].

A 65-year-old woman was seen in our clinic because of a 4-year history of slowly progressive left hand clumsiness and left limping. Neurologically, she had left-side spastic hemiparasis including her tongue, hand clumsiness, limb ataxia, constructional apraxia, and memory impairment. Dementia, parkinsonism and lower motor neuron sign were not confirmed. MRI study showed diffuse cerebral atrophy and shrinkage of the right cerebral peduncle and pontine base. SPECT (99mTc-ECD) study revealed hypoperfusion of the right fronto-parietal cortex. This is a rare case presented with slowly progressive left-side spastic hemiparasis, mimicking Mills' syndrome. In addition this case had other cortical signs, such as ipsilateral hand clumsiness, limb ataxia, constructional apraxia. Neuroimaging study suspects that the right front-parietal cortex is the primary lesion. Etiologically atypical motor neuron disease with adjacent cortical involvement is suspected rather than corticobasal degeneration with severe unilateral pyramidal tract degeneration.