NEW YORK (Reuters) -- Severe headaches that develop during airplane travel appear to be the result of rapid changes in pressure, rather than the high altitude or other causes.

Drs. M. S. Berilgen and B. M Jungen, of Firat University, Elazig, Turkey, describe six case studies of men who experienced severe airplane headaches. Their report is published in the journal Cephalalgia.

In one case, a 42-year-old man experienced a sudden severe jabbing pain in his right eye that began during the plane's descent and lasted for 30 to 40 minutes after the plane landed. Two years later a second attack occurred, and he went on to have three more episodes on separate occasions. There were no additional symptoms such as throbbing, nausea or blurred vision.

In another case, a 36-year-old man had a sudden stabbing pain around his right eye and right half of his face, which he described as "the blast of a bomb on the head." The attack lasted approximately 15 minutes and the pain lessened upon the plane's landing and stopped completely within 30 minutes. He later experienced three more similar attacks, with the second attack occurring a year after the first.

All six men experienced severe pain, usually on only one side of their head, which lasted for an average of 15 minutes. Only one of the six men had additional symptoms with the pain, which included stuffiness and nasal congestion.

One patient had a 10-year history of migraine, another had exercise headaches for the past 15 years and the others had no history of headaches.

The headache symptoms and patient histories rule out high-altitude headaches and cluster headaches, the physicians add.

Instead, they suggest that the headaches are the result of barotrauma, a condition that occurs during an airplane's descent as well as during diving, when an interaction occurs between the body's pressure and the rapidly changing pressure of the individual's outer surroundings.

"We think that since the most probable cause of this type of headaches is barotrauma, it is appropriate to designate them as 'barotrauma headache' or 'barotrauma-related headache,'" they conclude.

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