Application of SPM for Comparison of Striatal Dopamine Transporter Density between the Early Stage of the Parkinsonian Variant of Multiple System Atrophy and Parkinson's Disease

ABSTRACT

OBJECTIVE: Nigrostriatal dopaminergic neuronal degeneration is common to idiopathic Parkinson's disease(PD) and multiple system atrophy(MSA); although the topography of the nigral cell loss and striatal dopamine deficiency may differ. Currently, several functional neuroimaging techniques have been developed to differentiate between these two diseases. However, since the basal ganglia are usually poorly delineated in parkinsonian disorders on most functional neuroimaging techniques, most studies have failed to show the different pathologic changes among the parkinsonian disorders. In this study, we investigated alternation in regional loss of dopamine transporter binding using statistical parametric mapping(SPM) in patients with PD and the parkinsonian variant of MSA(MSA-P). METHODS: Ten PD and five MSA-P patients within 3 years of duration were studied with dual isotope brain SPECT following simultaneous injection of 370 MBq [99mTc] HMPAO and 111 MBq [123I] IPT. RESULTS: The basal ganglia were clearly visible on the fusion image, which was possible for quantitative and sta- tistical analysis. MSA-P patients showed significant loss of dopamine transporter binding in the left globus pallidus, anterior putamen and caudate nucleus in comparison to PD patients. CONCLUSION: This result may provide a useful tool to differentiate the pattern of loss of dopamine transporter bin- ding between PD and MSA-P.