title: [123I]IPT binding to the presynaptic dopamine transporter: variation of intra- and interobserver data evaluation in parkinsonian patients and controls.
abstract: Imaging the presynaptic dopamine transporter with cocaine analogues and single-photon emission tomography (SPET) has proven to be a potential diagnostic tool for classifying the extent and degree of dopaminergic nerve cell loss. For correct interpretation of scan results, however, knowledge of the intra-/interobserver variation of data evaluation is mandatory. Iodine-123 labelled N-(3-iodopropen-2-yl)-2beta-carbomethoxy-3beta-(chlorophenyl)tropane ([123I]IPT) SPET data of 10 controls and 30 parkinsonian patients with varying degrees of reduced IPT binding were analysed twice by an expert (intraobserver) and once by a less experienced physician in training (interobserver). For semiquantitative evaluation of specific IPT binding, ratios between total striatum, caudate and putamen and a background region were calculated. No significant differences were observed for either the intra- or the interobserver analyses. Variation was lower in controls than in the patient group. Overall variation indices were below 5%. Variation in interobserver results was only slightly higher than that in intraobserver results. The intra-/interobserver results showed highly significant correlations (r = 0.99). The intraclass correlation was higher than 0.9 for all evaluations. Our results indicate that the specific presynaptic striatal dopamine transporter binding assessed with IPT-SPET may be reproducibly analysed by the same and different observers in controls as well as in patients with varying degrees of reduced binding.
authors.affiliation: Department of Nuclear Medicine, University of Munich, Klinikum Grosshadern, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Linke
authors.forename: J
authors.initials: J
authors.lastname: Gostomzyk
authors.forename: K
authors.initials: K
authors.lastname: Hahn
authors.forename: K
authors.initials: K
authors.lastname: Tatsch
mesh_terms: D002352:Carrier Proteins / Q000378:metabolism*; D050483:Dopamine Plasma Membrane Transport Proteins; D006801:Humans; D007457:Iodine Radioisotopes; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D017072:Neostriatum / Q000000981:diagnostic imaging; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D015588:Observer Variation; D010300:Parkinson Disease / Q000000981:diagnostic imaging* / Q000382:microbiology*; D019275:Radiopharmaceuticals; D017661:Receptors, Presynaptic / Q000378:metabolism*; D015899:Tomography, Emission-Computed, Single-Photon; D014326:Tropanes
chemical_list: D002352:Carrier Proteins; D050483:Dopamine Plasma Membrane Transport Proteins; D007457:Iodine Radioisotopes; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D019275:Radiopharmaceuticals; D017661:Receptors, Presynaptic; D014326:Tropanes; C087210:N-(3-iodopropen-1-yl)-2-carbomethoxy-3-(4-chlorophenyl)tropane