Molecular Imaging in CANVAS: A Contribution for Differential Diagnosis?

Abstract

AbstractBackgroundPhenotypes of CANVAS are increasingly diversified, including bradykinesia and dysautonomia, so that its primary differential diagnoses are multiple system atrophy‐cerebellar type (MSA‐c), and spinocerebellar ataxia type 3 (SCA3). This case series aims to highlight key molecular imaging findings in CANVAS.CasesWe report a case series of six patients with CANVAS who underwent nuclear medicine examinations in our center and 13 patients from the literature. These include 18F‐FDG brain positron emission tomography (PET), single photon emission computed tomography (SPECT) of dopamine transporter (DaT) activity, and 123I‐MIBG cardiac scintigraphy of noradrenergic transmission.ConclusionsIn CANVAS, 18F‐FDG brain PET mainly shows cerebellar hypometabolism, with preserved brainstem and striatum metabolism, contrasting with SCA3 and MSA‐c. Dopaminergic denervation on scintigraphy seems to be associated with clinical parkinsonism, ranging from normal to severely impaired DaT SPECT. Additionally, 123I‐MIBG cardiac scintigraphy might show denervation in CANVAS, similar to SCA3, but not in most MSA‐c patients.