群発頭痛
A 35-year-old man complained of a sudden onset of severe headache. For the past two weeks, he woke up around 3:00 a.m. due to soreness behind the left eye. His pain continued for about an hour. Today, he visited the emergency department at 5:30 a.m. His consciousness was clear, but he appeared restless. His body temperature was 36.4℃. Pulse rate was 84/min. Blood pressure was 136/80mmHg. Conjunctival hyperemia and tearing of the left eye were observed. There were no meningeal signs. MRI and MRA of the head showed no abnormalities. What is the most likely diagnosis?
- amigraine
- bmeningitis
- cbrain tumor
- cluster headache
- esubarachnoid hemorrhage
正解：D
要点
2週間続く夜間の片側眼窩部痛＋同側の結膜充血・流涙という反復パターンと、髄膜刺激徴候なし・MRI/MRA正常という除外所見から、群発頭痛と診断できる。
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