慢性副鼻腔炎に起因した急性頭蓋内硬膜外血腫の1例

A Case of Acute Intracranial Epidural Hematoma Caused by Chronic Nasal Sinusitis

Ⅰ．はじめに

　急性頭蓋内硬膜外血腫（以下，硬膜外血腫と呼ぶ）は一般的に頭部外傷に伴う疾患であるが，非外傷性に発症することもあり，その原因として悪性疾患や凝固異常，血管奇形などが報告されている．われわれは，慢性副鼻腔炎で不定期に治療を受けていたが，激しい頭痛を伴った硬膜外血腫を発症した症例を経験し，その原因は慢性副鼻腔炎であると診断した．これまで報告されている副鼻腔炎に起因する硬膜外血腫10例についても考察し^{1-5,6,8,10-12)}，副鼻腔炎による硬膜外血腫の臨床像を明らかにする．

　Non-traumatic intracranial acute epidural hematoma（EDH）is rare. It is mostly caused by coagulation disorders, dural metastasis, or vascular malformations of the dura. We report a case of non-traumatic acute EDH caused by chronic nasal sinusitis and review the literature comprising 10 cases of acute EDH caused by chronic nasal sinusitis.

　A 16-year-old boy visited our outpatient clinic with a 2-day history of severe headache. He did not have fever or neurological abnormalities and showed no evidence of head trauma. Cranial computed tomography（CT）revealed sphenoid sinusitis and a small amount of epidural air in the middle fossa, but no other intracranial abnormalities. After eight days with no subsequent history of trauma, radiological exams showed a massive acute epidural hematoma in the left middle fossa and temporal convexity without any vascular lesion or skull fracture. The patient underwent a hematoma evacuation that revealed neither a skull fracture nor a vascular abnormality. In this adolescent, chronic nasal sinusitis caused fragility of the meningeal artery wall, an air collection in the epidural space, and the detachment of the dura mater from the inner surface of the skull, thereby resulting in a non-traumatic acute EDH.