title: The diagnostic value of dopamine transporter imaging and olfactory testing in patients with parkinsonian syndromes.
abstract: The aim of the study was to compare the efficacy of olfactory testing and presynaptic dopamine imaging in diagnosing Parkinson's disease (PD) and atypical parkinsonian syndromes (APS); to evaluate if the combination of these two diagnostic tools can improve their diagnostic value. A prospective investigation of 24 PD patients, 16 APS patients and 15 patients with non-parkinsonian syndromes was performed during an 18-month period. Single photon emission computed tomography with the presynaptic radioligand (123)I-FP-CIT (DaTSCAN(®)) and olfactory testing with the Brief 12-item Smell Identification Test (B-SIT) were performed in all patients. DaTSCAN was analysed semi-quantitatively, by calculating two different striatal uptake ratios, and visually according to a predefined ranking scale. B-SIT score was significantly lower for PD patients, but not significantly different between APS and non-parkinsonism. The visual assessment of DaTSCAN had higher sensitivity, specificity and diagnostic accuracy compared to olfactory testing. Most PD patients (75%) had visually predominant dopamine depletion in putamen, while most APS patients (56%) had visually severe dopamine depletion both in putamen and in caudate nucleus. The combination of DaTSCAN and B-SIT led to a higher rate of correctly classified patients. Olfactory testing can distinguish PD from non-parkinsonism, but not PD from APS or APS from non-parkinsonism. DaTSCAN is more efficient than olfactory testing and can be valuable in differentiating PD from APS. However, combining olfactory testing and DaTSCAN imaging has a higher predictive value than these two methods separately.
authors.affiliation: Department of Radiology, Linköping University, 581 85, Linköping, Sweden. charalampos.georgiopoulos@regionostergotland.se.|Department of Medical and Health Sciences, Linköping University, 581 85, Linköping, Sweden. charalampos.georgiopoulos@regionostergotland.se.|Center for Medical Image Science and Visualization (CMIV), Linköping University, 581 85, Linköping, Sweden. charalampos.georgiopoulos@regionostergotland.se.
authors.forename: Charalampos
authors.initials: C
authors.lastname: Georgiopoulos
authors.affiliation: Department of Clinical Physiology, Linköping University, 581 85, Linköping, Sweden.|Department of Medical and Health Sciences, Linköping University, 581 85, Linköping, Sweden.
authors.forename: Anette
authors.initials: A
authors.lastname: Davidsson
authors.affiliation: Department of Medical and Health Sciences, Linköping University, 581 85, Linköping, Sweden.|Center for Medical Image Science and Visualization (CMIV), Linköping University, 581 85, Linköping, Sweden.
authors.forename: Maria
authors.initials: M
authors.lastname: Engström
authors.affiliation: Department of Surgical Sciences/Radiology, Uppsala University, Akademiska sjukhuset, 751 85, Uppsala, Sweden.
authors.forename: Elna-Marie
authors.initials: EM
authors.lastname: Larsson
authors.affiliation: Department of Clinical Physiology, Linköping University, 581 85, Linköping, Sweden.|Department of Medical and Health Sciences, Linköping University, 581 85, Linköping, Sweden.
authors.forename: Helene
authors.initials: H
authors.lastname: Zachrisson
authors.affiliation: Department of Neurology, Linköping University, 581 85, Linköping, Sweden.|Department of Clinical and Experimental Medicine, Linköping University, 581 85, Linköping, Sweden.
authors.forename: Nil
authors.initials: N
authors.lastname: Dizdar
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000503:physiopathology; D003937:Diagnosis, Differential; D050483:Dopamine Plasma Membrane Transport Proteins / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009833:Olfactory Pathways / Q000000981:diagnostic imaging / Q000503:physiopathology*; D010300:Parkinson Disease / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology; D020734:Parkinsonian Disorders / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology; D011877:Radionuclide Imaging; D012903:Smell / Q000502:physiology*
chemical_list: D050483:Dopamine Plasma Membrane Transport Proteins
keywords: 123I-FP-CIT SPECT; Atypical parkinsonism; Olfaction; Parkinsonian syndromes; Parkinson’s disease