We compared the results of123I-iodobenzamide (123I-IBZM) single photon emission computed tomography (SPECT) and11C-raclopride positron emission tomography (PET) in 22 patients with parkinsonism. Nineteen patients were clinically diagnosed as having Parkinson's disease, two patients presented with atypical parkinsonism (i.e. clinical signs of Parkinson's disease and a subsequent poor response to dopamimetic drugs) and one patient was diagnosed as having Wilson's disease. All patients were drug naive. The SPECT data were semiquantitatively evaluated by calculating the ratios of striatal (basal ganglia, BG) IBZM binding to IBZM binding in various reference areas, i.e. the frontal cortex (BG/FC), the occipital cortex (BG/OC) and the cerebellum (BG/CE). In PET studies similar regions of interest were derived and ratios of striatal to cerebellar raclopride activity were determined.I23I-IBZM SPECT results significantly correlated to specific11C-raclopride binding. This correlation was not significantly different when the frontal cortex (P=0.05, r=0A2), occipital cortex (P11C-raclopride binding were considered, no significant correlation was obtained. Qualitative changes of dopamine D2 receptor binding, such as asymmetry, were equally recognized. This intraindividual comparison in patients with parkinsonism proves the previous assumption that binding of ligands to dopamine D2 receptors assessed by nC-raclopride PET is reflected by123I-IBZM SPECT. However, an increase of dopamine D2 receptor binding can only be discovered by PET.
|Number of pages||8|
|Journal||Nuclear Medicine Communications|
|Publication status||Published - 1994|
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging
- Radiological and Ultrasound Technology