Circadian rhythm sleep disorder associated with pontine lesion.

A 55-year-old man presented with excessive daytime sleepiness and a circadian rhythm sleep disorder. Magnetic resonance imaging of the brain revealed a pontine lesion distinguishable from major cerebrovascular disease, demyelination and neoplasm. Benzodiazepines, antidepressants, methylcobalamine and thyroxine failed to synchronize the circadian rhythm. Antiepileptic drugs aggravated the condition, while melatonin and protireline partially relieved the patient from poorly controlled sleep disorder. A pontine lesion appeared to be related to the circadian rhythm sleep disorder of the patient.