Is There Any Clinical Value of Adding 123I-Metaiodobenzylguanidine Myocardial Scintigraphy to 123I-Ioflupane (DaTscan) in the Differential Diagnosis of Parkinsonism?

Abstract

Purpose The aim of the study is to evaluate the impact of myocardial 123I-metaiodobenzylguanidine (MIBG) in the diagnosis, clinical management, and differential diagnosis of Parkinson disease (PD) and non-PD parkinsonism. Methods The study enrolled 41 patients with parkinsonism. An initial diagnosis was reached after thorough clinical and imaging evaluation. After 2 to 5 years of follow-up, a final diagnosis was established. All patients underwent, soon after their initial visit, presynaptic striatal DaT scintigraphy with 123I-FP-CIT (DaTscan) and 123I-MIBG myocardial scintigraphy. DaTscan is not specific to distinguish among different types of neurodegenerative parkinsonism. 123I-MIBG myocardial scintigraphy displays the functional status of cardiac sympathetic nerves, which is reduced in PD/dementia with Lewy bodies (DLB) and normal in atypical parkinsonian syndromes and secondary or nondegenerative parkinsonism. Results No patients showed adverse effects during or after both scintigraphies. A positive DaTscan was found in all patients in the PD/DLB group (17/17) and in 15 of 24 patients in the non-PD group. Myocardial 123I-MIBG scintigraphy was associated with lower sensitivity (82% vs 100%) but higher specificity than DaTscan (79% vs 38%) in diagnosis PD/DLB from non-PD parkinsonism. A positive scan result on both techniques, to confirm diagnosis of PD/DLB, significantly improved the specificity of DaTscan, from 38% to 75%, with no reduction in sensitivity. Conclusions Myocardial 123I-MIBG imaging provides complementary value to 123I-FP-CIT in the proper diagnosis, treatment plan, and differential diagnosis between PD and other forms of parkinsonism.

The potential role of the cardiac MIBG scan in differentiating the drug-induced Parkinsonism from Parkinson’s disease

“…In this regard, there are few head-to-head comparisons between the MIBG scan and dopamine transporter (DAT) scan to differentiate patients with PD from other parkinsonian syndromes, including DIP. A remarkable report by Stathaki et al [22] indicates a lower sensitivity but higher specificity for MIBG compared to DAT scan (sensitivity: 82% vs. 100%, specificity: 79% vs. 38%, respectively) in diagnosis of PD from non-PD parkinsonism. Many clinically DIPs show abnormality in DAT scans [23] .…”

High clinical diagnostic accuracy of combined salivary gland and myocardial metaiodobenzylguanidine scintigraphy in the diagnosis of Parkinson’s disease

“…No study has applied these quantitative indicators together to diagnose PD, including the differential diagnosis of PD and other parkinsonian syndromes. This approach reduces the examination cost and radiation exposure, and also saves time for the patients, especially when compared with previous studies on the diagnosis of PD by combining multiple imaging methods ( Sudmeyer et al, 2011 ; Stathaki et al, 2020 ).…”

“…Others with clinically relevant symptoms of parkinsonian syndrome, but without a diagnosis of clinically definite and possible PD or who did not match the dopamine transporter (DAT) and 18 F-fluorodeoxyglucose ( 18 F-FDG) positron emission tomography (PET) imaging findings of PD patients were classified as NPD by 2 independent neurologists. Referring to a similar diagnostic flow in previous studies ( Ishibashi et al, 2010 ; Stathaki et al, 2020 ), patients with unclassified Parkinsonian syndrome were included in the NPD group after excluding PD diagnosis. Moreover, considering that this study is an exploration of diagnostic methods, only comparing PD patients with other parkinsonian syndrome or healthy control group will reduce the accuracy of diagnostic tests ( Sackett and Haynes, 2002 ; Rutjes et al, 2006 ).…”

123I‐Metaiodobenzylguanidine Myocardial Scintigraphy in Discriminating Degenerative Parkinsonisms

“…MOVEMENT DISORDERS CLINICAL PRACTICE 2021. doi: 10.1002/mdc3.13227 5 PD from atypical parkinsonism, but the accuracy raised when MIBG scintigraphy was combined with 123I-Ioflupane SPECT. 24…”

“…In this study, 123 I‐MIBG myocardial scintigraphy was associated with 82% sensitivity and 79% specificity in discriminating PD from atypical parkinsonism, but the accuracy raised when MIBG scintigraphy was combined with 123I‐Ioflupane SPECT. 24 …”