外傷性中硬膜動脈偽性動脈瘤の1例

TRAUMATIC FALS ANEURYSM OF THE MIDDLE MANINGEAL ARTERY: A CASE REPORT

はじめに

　頭部外傷にともなう中硬膜動脈あるいは随伴静脈の損傷によって形成される硬膜外血腫は，日常しばしば経験するものであるが，おなじく中硬膜動・静脈の損傷によって生ずる偽性動脈瘤fals aneurysm^1），動静脈瘻（瘤）arterio-venous fistula （aneurysm）あるいは上矢状洞，横静脈洞などを含め頭蓋内の種々の静脈洞との間にみられる動脈静脈洞瘻arterio-cavernous fistulaなどの報告は稀なものとされている。

　私どもは頭部外傷後約2カ月目に精密検査のために来院した患者の脳血管写において，中硬膜動脈後枝における偽性動脈瘤を発見したが，本症例のように慢性期のものは文献的にも報告は少なく，興味ある症例と思われるので考察を加えて報告する。

Fals aneurysm of the middle meningeal artery associated with head injury is scarce with only 8 cases reported in ten years according to the liter-ature of Kuhn in 1964. All the cases were acute epidural or subdural hematoma.

The case in this paper is of a forty-year-old female whose fals aneurysm was found on her angio-graphy on the 2nd post traumatic month, and whohad no intracranial hematoma. Her fals aneurysm without epidural hematom occurred in the posterior branch of the middle meningeal artery of the left temporo-occipital where she had linear fracture, and was irregular in form. Its character had been clarified by serial angiography and selective external carotid angiography. The genetic mechanism of chronic fals aneurysm such in this case, which is very rare, involves intradural extravasation as sug-gested by Kuhn, Hasslar and Schechter.

As an operative technic of this fals aneurysm, extirpation or coagulation is recommended. In case repture is feared, ligation of the external carotid artery would be preferable in anticipation of the occlusion of fals aneurysm. Serial angiography and selective carotid angiography are the necessary per-formance to be done for this type of fals aneurysm to expose its character.