Loss of Swallow Tail Sign on Susceptibility-Weighted Imaging in Dementia with Lewy Bodies

Article type: Short Communication

Authors: Rizzo, Giovanni^{a; b; 1; *} | De Blasi, Roberto^{c; 1} | Capozzo, Rosa^{d; e} | Tortelli, Rosanna^{d; e} | Barulli, Maria Rosaria^{d; e} | Liguori, Rocco^{a; b} | Grasso, Daniela^f | Logroscino, Giancarlo^{d; e}

Affiliations: [a] IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy | [b] Department of Biomedical and Neuromotor Sciencest, tNeurology Unit, University of Bologna, Bologna, Italy | [c] Department of Diagnostic Imaging, Pia Fondazione di Culto e Religione “Card. G. Panico”, Tricase, Italy | [d] Department of Clinical Research in Neurology, University of Bari, Pia Fondazione di Culto e Religione “Card. G. Panico”, Tricase, Italy | [e] Department of Basic Medical Science, Neuroscience and Sense Organs, University of Bari, Bari, Italy | [f] IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy

Correspondence: [*] Correspondence to: Giovanni Rizzo, Department of Biomedical and Neuromotor Sciences, University of Bologna, and IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy. Tel.: +39 0514966112; E-mail: g.rizzo@unibo.it.

Note: [1] These authors contributed equally to this work.

Abstract: We assessed nigral dorsolateral hyperintensity (swallow tail sign) at susceptibility-weighted imaging using 3T-MRI in 15 dementia with Lewy bodies (DLB), 11 Alzheimer’s disease (AD), and 8 frontotemporal dementia (FTD) patients and 10 subjects with subjective memory complaint (SMC). More DLB patients lacked nigral hyperintesity (p < 0.05). Sensitivity, specificity, and accuracy of DLB diagnosis were, respectively: 80%, 64%, and 73% versus AD; 80%, 75%, and 78% versus FTD; and 80%, 90%, and 84% versus SMC. Considering bilateral loss, sensitivity decreased (53%) but specificity increased (82–100%). Swallow tail sign loss, especially if bilateral, can be useful for DLB diagnosis.

Keywords: Dementia with Lewy bodies, magnetic resonance imaging, nigrosome, swallow tail sign, susceptibility-weighted imaging

DOI: 10.3233/JAD-180687

Journal: Journal of Alzheimer's Disease, vol. 67, no. 1, pp. 61-65, 2019