Structural MRI correlates of amyotrophic lateral sclerosis progression

Area of Science:

• Neuroimaging
• Neurology
• Neurodegeneration

Background:

• Amyotrophic lateral sclerosis (ALS) exhibits variable brain degeneration and clinical progression.
• Structural MRI can detect brain changes reflecting ALS disease progression.

Purpose of the Study:

• To investigate the relationship between the spatial extent of brain degeneration and disease progression in ALS patients.
• To determine if extra-motor cortex and basal ganglia involvement predicts ALS progression.

Main Methods:

• 3-Tesla volumetric MRI and diffusion tensor imaging were used in 67 sporadic ALS patients and 38 controls.
• Patients were categorized into slow, intermediate, and rapid progression groups based on 6-month ALSFRS-R changes.
• Voxel-based morphometry and tract-based spatial statistics analyzed brain changes.

Main Results:

• ALS patients showed grey matter atrophy and decreased fractional anisotropy beyond the corticospinal tract (CST), notably in frontotemporal lobes and basal ganglia.
• The extent of brain changes correlated with the rate of functional decline (ΔALSFRS-R).
• Greater extra-motor and basal ganglia involvement was linked to faster disease progression.

Conclusions:

• The spatial extent of brain involvement, particularly in extra-motor regions, serves as an indicator of ALS progression.
• Widespread brain degeneration suggests a poorer prognosis and faster functional decline in ALS.