Positron emission tomography in progressive supranuclear palsy
M. H. Bhatt, B. J. Snow, W. R. Martin, R. Peppard and D. B. Calne
Department of Medicine, University Hospital, University of British Columbia, Vancouver, Canada.
Positron emission tomography with 6-[18F]fluoro-L-dopa (6-FD) provides in
vivo information on the function of nigrostriatal dopaminergic neurons. We
used 6-FD and positron emission tomography to investigate the integrity of
the nigrostriatal system in seven patients with progressive supranuclear
palsy. All patients had axial hypertonia, vertical gaze palsy, and
parkinsonian features. Dementia, pyramidal signs, and ataxia were seen in
varying proportions. We analyzed the scans with a graphic method to
calculate a steady-state 6-FD uptake rate constant for the whole striatum.
Results were compared with those obtained in seven age-matched controls. As
a group, the patients with progressive supranuclear palsy had reduced 6-FD
uptake constants. The 6-FD uptake constant correlated inversely with the
duration of the disease. Normal positron emission tographic findings in one
patient with the shortest duration of symptoms suggests that in early
progressive supranuclear palsy, parkinsonism may relate to dysfunction
distal to the dopaminergic neurons.
