Section Editor: Sandy Cheng-Yu Chen, M.D.
Taipei Medical University Hospital, Taipei, Taiwan
Figure Caption
Amyotrophic lateral sclerosis (ALS) refers to a selective degeneration of motor neurons of large pyramidal neurons of motor cortex and brainstem, resulting in eventual loss of corticospinal tracts (CST). The classic MR imaging feature is bilateral hyperintensities along CST extending from corona radiata (arrow in A) to posterior limbs of the internal capsules (arrows in B), and to cerebral peduncles (arrows in C) on T2WI/FLAIR. Clinically, patient presents with fasciculations and hyperreflexia. Both upper and lower motor neurons can be affected.