[A case presenting progressive hand clumsiness and discriminative sensory impairment]

A 58-year-old right-handed woman had presented slowly progressive clumsiness of the right hand over the past 8 years. The clumsiness of the right hand was characterized by difficulty in using scissors and a comb or in imitating finger patterns that resembled to limb kinetic apraxia. Mild rigidity, weakness and synkinetic movement were noted in the right upper extremity. Two-point discrimination, traced-figure identification and stereognosia were impaired on the right hand. However, she was neither demented nor aphasic. Brain MRIs revealed atrophy of the pre- and post-central gyri with marked preponderance on the left postcentral gyrus. 99mTc-ECD-SPECT uptake was decreased in the above brain atrophy areas. Upper limb SEPs were normal, but transcranial magnetic stimulation over the cortical hand motor area failed to evoke potentials from the right thenar muscles. These unique features seem to reflect focal cerebral degenerative process of unknown etiology, which may be classified into an asymmetric cortical degeneration syndrome (Caselli and Jack, 1992).