SPECT-EVALUATION OF THE MONOAMINE UPTAKE SITE LIGAND [I-123] -2-BETA-CARBOMETHOXY-3-BETA-(4-IODOPHENYL)-TROPANE ([I-123]BETA-CIT) IN UNTREATED PATIENTS WITH SUSPICION OF PARKINSON-DISEASE

Background: For a few years, data on SPECT-imaging of dopamine transpo rters with the cocaine derivate rbomethoxy-3-beta-(4-iodophenyl)-([I-1 23]beta-CIT) have been reported mostly in healthy subjects or animals, This study reflects our preliminary results with SPECT-imaging of dop amine transporters using the cocaine analogue I-123-beta-CIT in patien ts with untreated (de novo) parkinsonism, Methods: In 33 patients with clinical suspicion of Parkinson disease and 5 healthy controls, SPECT -imaging of dopamine transporters was performed 1, 4, and 24 hours aft er injection of 180 MBq of I-123-beta-CIT, which was generated by iodo destannylation, None of the patients or controls had been treated befo re with neuroleptical drugs or any other pharmaceuticals with known bi nding to the dopamine transporters, Clinical symptoms were staged by t he scales of Hoehn-Yahr (HYS), Unified Parkinson Disease Rating Scale (UPDRS), and the self-rating scale of Beck depression inventory (BDI), For evaluation, striatal/cerebellar ratios were calculated to every t ime point, Results: Significant correlations of I-123-beta-CIT uptake could be stated compared to UPDRS, HYS, and BDI values (Spearman corre lation, p < 0.05), The symptoms of rigor and akinesia showed a signifi cant correlation with the beta-CIT uptake, whereas the symptom of trem or failed, which may be caused by the location of tremor symptoms out of the striatum, Comparing the controls, a significant (p < 0.01) decr ease of tracer uptake in parkinsonian patients is stated on the images at 24 hours p.i. In our patients, tracer uptake does not depend signi ficantly on duration of disease and age, Conclusion: I-123-beta-CIT st ems to be a promising tool in imaging of untreated parkinsonian patien ts.