Diffusion Tensor Magnetic Resonance Imaging for Differentiating Multiple System Atrophy Cerebellar Type and Spinocerebellar Ataxia Type 3.

Chi-Wen Jao,Po-Shan Wang,Chien-An Duan,Yu-Te Wu,Bing-Wen Soong,Chao-Wen Huang,Chih-Chun Wu

doi:10.3390/brainsci9120354

Abstract

Multiple system atrophy cerebellar type (MSA-C) and spinocerebellar ataxia type 3 (SCA3) demonstrate similar manifestations, including ataxia, pyramidal and extrapyramidal signs, as well as atrophy and signal intensity changes in the cerebellum and brainstem. MSA-C and SCA3 cannot be clinically differentiated through T1-weighted magnetic resonance imaging (MRI) alone; therefore, clinical consensus criteria and genetic testing are also required. Here, we used diffusion tensor imaging (DTI) to measure water molecular diffusion of white matter and investigate the difference between MSA-C and SCA3. Four measurements were calculated from DTI images, including fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD), and mean diffusivity (MD). Fifteen patients with MSA-C, 15 patients with SCA3, and 30 healthy individuals participated in this study. Both patient groups demonstrated a significantly decreased FA but a significantly increased AD, RD, and MD in the cerebello-ponto-cerebral tracts. Moreover, patients with SCA3 demonstrated a significant decrease in FA but more significant increases in AD, RD, and MD in the cerebello-cerebral tracts than patients with MSAC. Our results may suggest that FA and MD can be effectively used for differentiating SCA3 and MSA-C, both of which are cerebellar ataxias and have many common atrophied regions in the cerebral and cerebellar cortex.

Highlights

Cerebellar ataxias can be categorized into two subgroups: hereditary or sporadic
Of diffusion tensor imaging (DTI) between health control and Multiple system atrophy cerebellar type (MSA-C) (Figure 4a), and Figure 4b illustrates the results between health control and Spinocerebellar ataxia type 3 (SCA3) groups
fractional anisotropy (FA) decreased in the MSA-C and SCA3 groups and axial diffusivity (AD), radial diffusivity (RD), and mean diffusivity (MD) were increased mainly in the cerebello-ponto-cerebral loops

Summary

Introduction

Cerebellar ataxias can be categorized into two subgroups: hereditary or sporadic. Spinocerebellar ataxia type 3 (SCA3), known as Machado–Joseph disease, is the most common hereditary cerebellar ataxia type [1,2]. SCA3 is caused by the expansion of a CAG repeat in the ataxin-3 gene [1,2]. The etiology of the cerebellar atrophy is currently known to involve chromosomal abnormalities and familial genetic predisposition [2]. Its symptoms include slow progressive ataxia, lisp, dysphagia, unclear writing font, delicate hand movement, unstable gait, and other movement control-related symptoms [3]. The cerebellum is one of the most affected areas in patients with SCA3; atrophy or

Methods

Results

Discussion

Conclusion