Frequency, distribution and characteristics of progressive supranuclear palsy in Italy: preliminary observations.

We report the number of pathologically proven cases of progressive supranuclear palsy, described in the Italian neurological literature from 1961 until now. A discussion of the diagnostic value of downward gaze palsy is made. A comparison with the number of similar cases described in the rest of the world and with the number of Parkinsonian patients who died in the same region in the corresponding year is attempted.