RT Journal Article SR Electronic T1 Sensitivity and Specificity of 99mTc-TRODAT-1 SPECT Imaging in Differentiating Patients with Idiopathic Parkinson’s Disease from Healthy Subjects JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 393 OP 401 VO 45 IS 3 A1 Yi-Hsin Weng A1 Tzu-Chen Yen A1 Min-Chi Chen A1 Pan-Fu Kao A1 Kai-Yuan Tzen A1 Rou-Shayn Chen A1 Shiaw-Pyng Wey A1 Gann Ting A1 Chin-Song Lu YR 2004 UL http://jnm.snmjournals.org/content/45/3/393.abstract AB The imaging of dopamine transporter (DAT) with 99mTc-TRODAT-1 ([2-[[2-[[[3-(4-chlorophenyl)-8-methyl-8-azabicyclo[3,2,1]oct-2-yl]methyl](2-mercaptoethyl)amino]ethyl]amino]ethanethiolato(3-)-N2,N2′,S2,S2′]oxo-[1R-(exo-exo)]-99mTc-technetium) and SPECT has been recently proposed to be a valuable and feasible means of assessment of the integrity of dopamine neurons. The purpose of this study was to further investigate the clinical correlations and the age-specific sensitivity and specificity of this new approach in the diagnosis of patients with idiopathic Parkinson’s disease (PD) that manifests in patients >50 y of age. Methods: SPECT imaging with 99mTc-TRODAT-1 was conducted in 78 consecutive PD patients and in 40 age-matched healthy subjects. The images were obtained 4 h after the intravenous injection of the tracer. The ratios of specific striatal binding to nonspecific occipital binding were calculated. S/O represents the ratio for whole striatal binding, whereas P/O and C/O represent the putamen and caudate nucleus, respectively. Statistical analyses of the sensitivity and specificity of these ratios in different age-specific subgroups were performed. The correlations between these ratios and clinical assessments were also analyzed. The age-related declines in the striatal binding in both patients and controls were given particular focus. Results: The S/O, C/O, and P/O ratios decreased significantly both contralaterally and ipsilaterally to the dominant symptomatic side in the PD group (P < 0.0001). The mean reduction of binding was found in the order of putamen (contralateral side, −81%; ipsilateral side, −67%) and caudate nucleus (contralateral side, −46%; ipsilateral side, −40%). The sensitivity and specificity of both P/O and S/O ratios were 100% in discriminating PD patients from healthy subjects in the age-specific groups. The binding ratios correlated negatively with the Unified Parkinson’s Rating Scale and Hoehn and Yahr (H–Y) staging. Of particular interest, the binding of the striatum contralateral to the asymptomatic side in H–Y stage I patients also decreased significantly. The age-related decline of these ratios was significant in the control group. Conclusion: We have demonstrated that 99mTc-TRODAT-1 SPECT has a high sensitivity and specificity for measuring the decrement of DAT in PD patients. In addition to its wide availability, we suggest that this new approach may serve as a diagnostic marker for PD.