Evaluating the cerebral correlates of survival in amyotrophic lateral sclerosis

Abstract

Objective: To evaluate cerebral degenerative changes in ALS and their correlates with survival using 3D texture analysis. Methods: A total of 157 participants were included in this analysis from four neuroimaging studies. Voxel-wise texture analysis on T1-weighted brain magnetic resonance images (MRIs) was conducted between patients and controls. Patients were divided into long- and short-survivors using the median survival of the cohort. Neuroanatomical differences between the two survival groups were also investigated. Results: Whole-brain analysis revealed significant changes in image texture (FDR P < 0.05) bilaterally in the motor cortex, corticospinal tract (CST), insula, basal ganglia, hippocampus, and frontal regions including subcortical white matter. The texture of the CST correlated (P < 0.05) with finger- and foot-tapping rate, measures of upper motor neuron function. Patients with a survival below the media of 19.5 months demonstrated texture change (FDR P < 0.05) in the motor cortex, CST, basal ganglia, and the hippocampus, a distribution which corresponds to stage 4 of the distribution TDP-43 pathology in ALS. Patients with longer survival exhibited texture changes restricted to motor regions, including the motor cortex and the CST. Interpretation: Widespread gray and white matter pathology is evident in ALS, as revealed by texture analysis of conventional T1-weighted MRI. Length of survival in patients with ALS is associated with the spatial extent of cerebral degeneration.