title: Evaluation of patients with Clinically Unclear Parkinsonian Syndromes submitted to brain SPECT imaging using the technetium-99m labeled tracer TRODAT-1.
abstract: Despite its relatively high prevalence Parkinson's Disease (PD) is still misdiagnosed in approximately 25% of cases. In this study our aim was to evaluate patients with Clinically Unclear Parkinsonian Syndromes (CUPS) submitted to brain SPECT imaging using the technetium-99m labeled Dopamine Transporter (DAT) tracer TRODAT-1. We recruited 15 subjects with CUPS and matched them with 13 patients with probable PD and 13 healthy control subjects (HCS). A SPECT with TRODAT-1 was performed at the baseline evaluation and patients from the CUPS were followed-up for 2-years to ensure or not PD diagnosis ("gold-standard"). The mean+/-SD results from Right and Left striatum Binding Potential (BP) were, respectively, 1.08+/-0.20 and 1.04+/-0.16 in the HCS group, 0.47+/-0.16 and 0.53+/-0.17 in the PD group, and 0.68+/-0.11 and 0.84+/-0.17 in the CUPS group. The rate of disagreement between baseline SPECT in the CUPS group as compared to the "gold standard" diagnosis (clinical diagnosis of PD on follow-up) was of 20%. The sensitivity of the SPECT with TRODAT-1 was 100%, while specificity was 70%. In conclusion, our data provided further information about the role of the technetium-99m labeled tracer TRODAT-1 as a biomarker of DAT reduction that can also be used in the diagnosis of patients with CUPS.
authors.affiliation: Department of Neurology and Neurosurgery, Movement Disorder Unit, Federal University of São Paulo, Sao Paulo, Brazil. cf.andre@gmail.com
authors.forename: Andre C
authors.initials: AC
authors.lastname: Felicio
authors.forename: Clecio
authors.initials: C
authors.lastname: Godeiro-Junior
authors.forename: Ming C
authors.initials: MC
authors.lastname: Shih
authors.forename: Vanderci
authors.initials: V
authors.lastname: Borges
authors.forename: Sônia M A
authors.initials: SM
authors.lastname: Silva
authors.forename: Patrícia de Carvalho
authors.initials: Pde C
authors.lastname: Aguiar
authors.forename: Marcelo Q
authors.initials: MQ
authors.lastname: Hoexter
authors.forename: Orlando G P
authors.initials: OG
authors.lastname: Barsottini
authors.forename: Luiz A F
authors.initials: LA
authors.lastname: Andrade
authors.forename: Rodrigo A
authors.initials: RA
authors.lastname: Bressan
authors.forename: Henrique B
authors.initials: HB
authors.lastname: Ferraz
mesh_terms: D001921:Brain / Q000000981:diagnostic imaging*; D003342:Corpus Striatum / Q000000981:diagnostic imaging; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D007839:Functional Laterality; D006801:Humans; D008297:Male; D008875:Middle Aged; D015609:Organotechnetium Compounds; D010300:Parkinson Disease / Q000175:diagnosis / Q000000981:diagnostic imaging; D020734:Parkinsonian Disorders / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity; D015899:Tomography, Emission-Computed, Single-Photon; D014326:Tropanes
chemical_list: D015609:Organotechnetium Compounds; D014326:Tropanes; C104196:technetium Tc 99m TRODAT-1