In statistical terms a group of subjects, closely linked in time and/or place of occurrence. For example, geographical clusters of LEUKAEMIA have been found – that is, an unexpectedly large number of persons with the disease who live in close proximity. Much research goes into trying to discover the cause of clusters but sometimes they appear to have occurred randomly.
An aggregation of cases of a disease or other health-related condition which are closely grouped in time and place. The number of cases may or may not exceed the expected number; frequently the expected number is not known.
A type of MIGRAINE occurring in clusters – that is, a patient may have an attack daily for several days and then none for weeks or months. The pain is on one side of the head, often centred over the eye. The pain is excruciatingly severe and often associated with tearing, nasal discharge and production of thick saliva from the same side of the mouth. It is treated either with drugs such as SUMATRIPTAN or by breathing 100 per cent oxygen.... cluster headaches
a variant of *migraine more common in men than in women (ratio 9:1). The unilateral pain around one eye is very severe and lasts between 15 minutes and 3 hours. The attacks commonly occur in the early hours of the morning but may occur up to eight times a day. The pain is associated with drooping of the eyelid (*ptosis), a bloodshot eye, a small pupil, and/or excessive production of tears in the eye. The acute treatment is with high-flow inhaled oxygen in conjunction with antimigraine drugs (5HT1 agonists) and prophylaxis is with such drugs as verapamil, lithium, or methysergide.... cluster headache
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