[99Mtc]Tc-Trodat-1 Scan Diagnostic Accuracy for Differentiation of Dementia of Lewy Body From Alzheimer's Disease Publisher



Baseri F¹ ; Aghamollaii V² ; Salehi Y³ ; Farzanehfar S³ ; Hosseini A³ ; Tafakhori A⁴ ; Abbasi M³ Show Affiliations
Source: Iranian Journal of Nuclear Medicine Published:2024

Abstract

Introduction: Dopamine transporter (DAT) receptors are reduced in the striatum in dementia of Lewy body (DLB) but normal in Alzheimer's disease (AD). We assessed the diagnostic accuracy of TRODAT-1 imaging to differentiate patients with DLB from AD. Methods: Patients with DLB or AD underwent SPECT TRODAT imaging by [99mTc]Tc-TRODAT-1. Visual interpretation and quantification analyses were done. The activity of the right and left caudate nucleus (CN), putamen (P), striatum (S) as a whole, background (BG), and occipital area (OC) were calculated in addition to the ratio of right and left CN/OC, P/OC, and S/BG. Absolute right and left value difference of the striatum (∆S), putamen (∆P), and caudate (∆CN) to OC or BG were also calculated. The diagnostic accuracy of the visual and quantitative method were compared between patients with AD and LBD. The area under the ROC curve (AUC) was analyzed. Results: Twenty-five patients (15 DLB and 10 AD) were included. Scans were visually interpreted as DLB, AD, and non-diagnostic in 11, 13, and one patients, respectively. Sensitivity, specificity, and accuracy of the scan were 57.1% (28.9-82.3), 70% (34.8-93.3), and 62.5% (40.6-81.2), respectively. CN/OC, P/OC, and S/BG in the left, right, and bilaterally were statistically same between two groups. The AUC of ∆CN/OC was 70.7%. The optimal cut-off value for ∆CN/BG to diagnose DLB was 6.6% with a sensitivity, specificity, and accuracy, of 86.7%, 50%, and 72.0%, respectively. Conclusion: The [99mTc]Tc-TRODAT-1 imaging has limited diagnostic accuracy for discrimination of DLB and AD patients. Copyright © 2024 The Authors. Published by Tehran University of Medical Sciences.