Horner's syndrome from hypothalamic infarction

Horner's syndrome results from the paralysis of cervical (in the neck) sympathetic nerves. The symptoms include drooping of the eyelid and a sinking in of the eyeball. There is often flushing on the affected side of the face. The lesion causing Horner's syndrome may be located at any point along the pathway from the hypothalamus to the eye socket. Horner's syndrome is probably caused most commonly by lesions in the brainstem. The authors now report a case in which Horner's syndrome resulted from an infarction (reduction in blood flow) of the hypothalamus. When Horner's syndrome results from a hypothalamic lesion, the cause is usually a tumor or a hemorrhage. Because of the rich blood supply to this part of the brain, infarctions are rare. In this case (a 62-year-old woman), nuclear magnetic imaging demonstrated a hypothalamic infarction, which extended into the posterior internal capsule. While some symptoms such as dysarthria (impaired speech) were present which could be attributed to the lesion in the internal capsule, there were no other symptoms indicative of hypothalamic damage except the Horner's syndrome. In up to 30 percent of all individuals, a fetal pattern of circulation can persist into adulthood; in this pattern, the entire blood supply of the hypothalamus derives from the carotid artery. Therefore, the hypothalamus is sensitive to disruptions in carotid blood flow in these subjects. In the current patient, however, arteriography revealed no such persistent fetal circulation. The patient was placed on aspirin and sent home; she remains asymptomatic and a follow-up at four weeks revealed only a narrow furrowing of the left eyelid. (Consumer Summary produced by Reliance Medical Information, Inc.)