Cortical atrophy in Parkinson disease: correlation between clinical and CT findings with special emphasis on prefrontal atrophy.

Thirty-seven patients with Parkinson disease were evaluated clinically and with computed tomography in order to determine the incidence of prefrontal atrophy. An age-matched healthy control group was also scanned. The computed tomographic criteria used were the width of cortical sulci and ventriculocerebral indices. Parkinsonian patients with frontal cortical atrophy represent only one patient out of three. They are much older than parkinsonian patients with normal computed tomographic scans, and the onset of their illness occurs later. No significant difference was found according to gender, parkinsonian clinical triad, psychomotor study, or mean duration of illness and/or dopatherapy to the time of computed tomography. This work seems to separate two Parkinson diseases: one beginning before 65 years and damaging the nigrostriate system, and another beginning after 65 years and damaging both the nigrostriate system and the cortex, particularly the frontal cortex.