123I-Metaiodobenzylguanidine Myocardial Scintigraphy in Discriminating Degenerative Parkinsonisms

Mauro Catalan; Franca Dore; Paola Polverino; Claudio Bertolotti; Arianna Sartori; Lucia Antonutti; Alberto Cucca; Giovanni Furlanis; Selene Capitanio; Paolo Manganotti

doi:10.1002/mdc3.13227

¹²³I-Metaiodobenzylguanidine Myocardial Scintigraphy in Discriminating Degenerative Parkinsonisms

Mov Disord Clin Pract. 2021 May 7;8(5):717-724. doi: 10.1002/mdc3.13227. eCollection 2021 Jul.

Authors

Affiliations

¹ Clinical Unit of Neurology, Department of Medical Sciences University Hospital and Health Services of Trieste, University of Trieste Trieste Italy.
² Nuclear Medicine, Imaging Diagnostic Department University Hospital and Health Services of Trieste, University of Trieste Trieste Italy.
³ Department of Life Sciences University of Trieste Trieste Italy.
⁴ The Marlene and Paolo Fresco Institute for Parkinson's and Movement Disorders, Department of Neurology NYU School of Medicine New York New York USA.
⁵ Department of Rehabilitation Medicine Villa Margherita Fresco Parkinson Center Vicenza Italy.
⁶ Nuclear Medicine, IRCCS Ospedale Policlinico San Martino Genoa Italy.
⁷ Department of Nuclear Medicine ASST, Grande Ospedale Metropolitano Niguarda Milan Italy.

Abstract

Background: ¹²³I-Metaiodobenzylguanidine (¹²³I-MIBG) myocardial scintigraphy is a useful technique to differentiate Parkinson's disease (PD) from atypical parkinsonisms, since it is generally abnormal in PD and normal in the latter. Reduction of myocardial MIBG uptake is a supportive feature in the latest PD diagnostic criteria.

Objectives: To explore the clinical contribution of myocardial scintigraphy in discriminating different forms of parkinsonisms, especially when atypical features are present.

Methods: Forty-one patients with parkinsonism underwent a ¹²³I-MIBG myocardial scintigraphy in our Movement Disorders Center. Disease evolution was reviewed by applying the latest disease criteria for PD, multiple system atrophy (MSA), progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS), as appropriate. Three diagnostic times were defined: T1 (before scintigraphy execution), T2 (immediately after the exam) and T3 (two years later). Early and delayed heart/mediastinum (H/M) ratios and washout rate (WR) were analyzed.

Results: Myocardial scintigraphy showed impaired MIBG uptake in 12 out of 15 patients with a definite PD diagnosis, while normal uptake was found in 20 of 26 patients with no-PD. Early and delayed H/M ratios were significantly lower in PD compared to overall no-PD patients and MSA patients. ¹²³I-MIBG myocardial scintigraphy was abnormal in all PD patients with dysautonomia. After ¹²³I-MIBG myocardial scintigraphy (T2), in 9 patients (22%) an improvement of diagnostic accuracy was reached.

Conclusions: Diagnostic accuracy of myocardial scintigraphy in distinguishing PD from atypical parkinsonism was suboptimal. Nevertheless, this study confirmed the relevance of ¹²³I-MIBG myocardial scintigraphy for the discrimination of PD from atypical parkinsonism, especially when dysautonomic symptoms are present.

Keywords: 123I‐MIBG myocardial scintigraphy; Parkinson's disease; atypical parkinsonism; differential diagnosis; multiple system atrophy.