Amyotrophic Lateral Sclerosis

•        MC form of motor neuron disease.

•        Progressive, neurodegenerative disorder.

•        Upper (hyper reflexia, spasticity) and lower (fasciculation, atrophy) neuronal symptoms

–       No autonomic, sensory, or cognitive involvement.

•        Male predilection, onset in middle and late adult years.

Selective degeneration of somatic motor neurons of brain stem/spinal cord ( LMN), large pyramidal
neurons of motor cortex (upper motor neurons, UMN), eventual loss of corticospinal tract (CST) fibers.

Best diagnostic clue bilateral hyperintensities along CST extending from corona radiata to brain stem on
T2WI/PD /FLAIR.