[Correlation between corticospinal tract degeneration through magnetic resonance imaging, and functional scale...

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that affects the corticospinal tract. ALS functional rating scale (ALSFRS) is a questionnaire that quantifies motor deficits, while diffusion tensor imaging (DTI) evaluates the integrity of fibers through the fractional anisotropy (FA). In the present study, seven ALS patients were evaluated by ALSFRS and immediately submitted to DTI, getting FA values in the following regions: cerebral peduncle (PC), internal capsule (CI) and the white matter under the primary motor cortex (M1), secondary motor cortex (M2) and somesthetic cortex (SI). A control group was constituted by twelve healthy individuals. FA values in patients were significantly lower when compared with controls, with a tendency to higher reductions in the right hemisphere and more inferior regions. Interestingly, FA values were reduced in somesthetic area. No correlation was observed between symptoms duration and FA values. Despite the correlation observed between ALSFRS scores and degeneration in PC and CI, our results suggest that this subjective scale is not a good parameter for the evaluation of the structural damage in encephalic portions of the corticospinal tract.