Background: Both movement (MD) and cognitive (CD) disorders can occur associated
in some neurodegenerative diseases, such as Parkinson’s disease (PD) and Alzheimer’s disease
Objective: We further investigated the usefulness of 123I-Ioflupane SPECT and 18F-FDG PET
combined use in patients with these disorders in the early stage.
Methods: We retrospectively enrolled twenty-five consecutive patients with MD and CD clinical
symptoms of recent appearance. All patients had undergone neurologic examination, neuropsychological
tests, and magnetic resonance imaging. 123I-Ioflupane SPECT was performed in all cases,
followed by 18F-FDG PET two weeks later. In the two procedures, both qualitative (QL) and quantitative
(QN) image analyses were determined.
Results: In patients with both 123I-Ioflupane SPECT and 18F-FDG PET pathologic data, associated
dopaminergic and cognitive impairments were confirmed in 56% of cases. Pathologic SPECT
with normal PET in 16% of cases could diagnose MD and exclude an associated CD, despite clinical
symptoms. On the contrary, normal SPECT with pathologic PET in 28% of cases could exclude
basal ganglia damage while confirming CD. QN 123I-Ioflupane SPECT analysis showed better performance
than QL since QN correctly characterized two cases of MD with normal QL. Moreover,
correct classification of normal metabolism was made only by QN analysis of 18F-FDG PET in
four cases, despite suspect areas of hypometabolism at QL.
Conclusion: The combined use of these imaging procedures proved a reliable diagnostic tool to accurately
identify and characterize MD and CD in early stage. QN analysis was effective in supporting
QL evaluation, and its routine use is suggested, especially with inconclusive QL.