PET imaging of the dopamine transporter in progressive supranuclear palsy and Parkinson's disease.
OBJECTIVE
To differentiate the patterns of dopamine transporter loss between idiopathic PD and progressive supranuclear palsy (PSP).


METHODS
We used the radiotracer [11C]-WIN 35,428 and PET. Regional striatal dopamine transporter binding was measured in the caudate, anterior putamen, and posterior putamen of six patients with L-dopa-responsive stage 2 PD, six patients with PSP, and six age-comparable healthy controls.


RESULTS
In patients with idiopathic PD, the most marked abnormality was observed in the posterior putamen (77% reduction), whereas transporter density in the anterior putamen (60% reduction) and the caudate (44% reduction) was less affected. Unlike the patients with PD, the PSP group showed a relatively uniform degree of involvement in the caudate (40% reduction), anterior putamen (47% reduction), and posterior putamen (51% reduction). When posterior putamen/caudate ratios were calculated, these values were significantly lower in patients with PD than they were in patients with PSP (p = 0.0008) and the control group (p < 0.0001).


CONCLUSIONS
Patients with PD have a more pronounced loss of dopamine transporters in the posterior putamen due to a subdivisional involvement of nigrostriatal dopaminergic projections in idiopathic PD. This technique is useful in the determination of neurochemical changes underlying PD and PSP, thus differentiating between them.
Ilgin
N
N
Department of Radiology, Johns Hopkins Medical Institutions, Baltimore, MD, USA.
Zubieta
J
J
Reich
S G
SG
Dannals
R F
RF
Ravert
H T
HT
Frost
J J
JJ
D002250:Carbon Radioisotopes; D002352:Carrier Proteins / Q000378:metabolism*; D003042:Cocaine / Q000031:analogs & derivatives; D050483:Dopamine Plasma Membrane Transport Proteins; D018765:Dopamine Uptake Inhibitors; D006801:Humans; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D008875:Middle Aged; D009419:Nerve Tissue Proteins; D010300:Parkinson Disease / Q000000981:diagnostic imaging* / Q000378:metabolism; D013494:Supranuclear Palsy, Progressive / Q000000981:diagnostic imaging* / Q000378:metabolism; D014055:Tomography, Emission-Computed
D002250:Carbon Radioisotopes; D002352:Carrier Proteins; D050483:Dopamine Plasma Membrane Transport Proteins; D018765:Dopamine Uptake Inhibitors; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; C021279:(1R-(exo,exo))-3-(4-fluorophenyl)-8-methyl-8- azabicyclo(3.2.1)octane-2-carboxylic acid, methyl ester; D003042:Cocaine