Objectives: To observe the ultra-structural changes of the brain tissue in a patient with motor neuron disease.
Methods: A stereotactic brain biopsy of the local lesions was performed based on the abnormal signals on magnetic resonance images, and the brain tissues were underwent light and electronic microscopic examination.
Results: Extensive extra-cellular edema and neuron necrosis were found in the internal capsule and thalamus. Metachromatic substances were found in the cyto-plasma and were characterized by electronic dense granules, arranged in flat plate layers or in flat lines. Disorganized and degenerating mitochondria were observed in astrocytes and neurons.
Conclusions: Ultra-structural observation of the brain tissues might be helpful in understanding the central neuropathological changes in a patient with MND. Characteristic metachromatic substances might be found in the cyto-plasma. Neurons in the brain of a patient with MND might undergo a process of degeneration.