Progression of white matter degeneration in amyotrophic lateral sclerosis: A diffusion tensor imaging study

Abstract

Whether longitudinal diffusion tensor MRI imaging (DTI) can capture disease progression in patients with amyotrophic lateral sclerosis (ALS) is unclear. The primary goal of this study was to determine if DTI detects progression of the corticospinal tracts (CST) degeneration in ALS. Seventeen ALS patients and 19 age- and gender-matched healthy controls were scanned with DTI at baseline for cross-sectional analyses. For longitudinal analyses, the ALS patients had repeat DTI scans after eight months. Tractography of the CST was used to guide regions-of-interest (ROI) analysis and complemented by a voxelwise analysis. Cross-sectional study found that baseline FA of the right superior CST was markedly reduced in ALS patients compared to controls. The FA reductions in this region correlated with the disease severity in ALS patients. Longitudinal study found that FA change rate of the right superior CST significantly declined over time. In conclusion, longitudinal DTI study captures progression of upper motor fiber degeneration in ALS. DTI can be useful for monitoring ALS progression and efficacy of treatment interventions.

Key words::

• Amyotrophic lateral sclerosis
• diffusion tensor imaging
• longitudinal study
• corticospinal tracts
• brain MRI

Acknowledgement

The authors thank Philip Insel for discussion on statistics. This research was funded in part by an ALS Association (ALSA) award and a grant from the National Center for Resource Research which was administered by the Northern California Institute for Research and Education, and with resources of the Veterans Affairs Medical Center, San Francisco, California.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.