Segmental abnormalities of white matter microstructure in multiple sclerosis and neuromyelitis optica spectrum disorder identified by automated fiber quantification

Yan Xie; Shaolong Wu; Houming Su; Yihao Yao; Hongquan Zhu; Yan Zhang; Wenzhen Zhu

doi:10.1016/j.msard.2024.106147

Segmental abnormalities of white matter microstructure in multiple sclerosis and neuromyelitis optica spectrum disorder identified by automated fiber quantification

Mult Scler Relat Disord. 2024 Oct 29:92:106147. doi: 10.1016/j.msard.2024.106147. Online ahead of print.

Authors

Yan Xie¹, Shaolong Wu¹, Houming Su¹, Yihao Yao¹, Hongquan Zhu¹, Yan Zhang², Wenzhen Zhu³

Affiliations

¹ Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
² Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China. Electronic address: [email protected].
³ Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China. Electronic address: [email protected].

PMID: 39504730
DOI: 10.1016/j.msard.2024.106147

Abstract

Background: Multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOSD) are different in pathogenesis, but both could lead to white matter (WM) microstructural damage. The aim of this study was to explore the differences in the patterns of WM fiber tract damage in relapsing-remitting MS (RRMS) and NMOSD by automated fiber quantification (AFQ).

Materials and methods: Forty-one RRMS patients, 30 NMOSD patients and 30 healthy controls (HC) underwent MRI examination. AFQ was applied to identify and quantify 100 equally spaced nodes of specific WM fiber tracts for each participant. Measurements of fractional anisotropy (FA), mean diffusion (MD), axial diffusivity (AD) and radial diffusivity (RD) for each segment of a specific fiber tract were compared between RRMS, NMOSD and HC.

Results: The decrease in FA was found in 7 fiber tracts in entire tract comparison and 9 fiber tracts in pointwise comparison in RRMS patients. However, the FA in left thalamic radiation (TR) and right uncinate fasciculus showed significant differences between RRMS and HC only in the pointwise comparison, but not in the entire tract comparison. The MD, AD and RD of WM fiber tracts in RRMS patients were extensively increased both in the entire level and in the pointwise level. NMOSD patients showed significant FA decrease in left TR and callosum forceps minor (CF_minor), and significant RD increase in CF_minor in the pointwise level. In the pointwise comparison between RRMS and NMOSD, significant FA decrease was found in right inferior fronto-occipital fasciculus and bilateral inferior longitudinal fasciculus in RRMS patients, focal or widespread MD, AD and RD increase was found in multiple fiber tracts.

Conclusion: The AFQ approach is a more sensitive way to reflect WM microstructural abnormalities, revealing extensive WM microstructural damage in RRMS and limited WM fiber tract damage in NMOSD.

Keywords: Automated fiber quantification; Diffusion tensor imaging; Multiple sclerosis; Neuromyelitis optica spectrum disorder; White matter.