Motor neurone disease principally affects the bulbar nerves, while the ocular nerves are spared. This results in symptoms of dysarthria, dysphagia, nasal regurgitation, and choking. Symptoms may be progressive as the neuroma enlarges and may be accompanied by cerebellar ataxia. Trigeminal neuralgia occurs almost always in the elderly. Younger patients who develop the condition under the age of 50 years should be investigated for multiple sclerosis and underlying tumour. Muscle fasciculations are a feature of lower motor neurone lesions. They consist of irregular contractions of muscle fibres which are innervated by the same motor unit. Motor neurone disease is a sporadic disease of unknown cause. It is more common in men and affects the motor neurones as a result of degeneration of the: betz cells, pyramidal fibres, cranial nerve nuclei, and anterior horn cells.