慢性硬膜下血腫術後のsubdural tension pneumocephalus

SUBDURAL TENSION PNEUMOCEPHALUS AFTER TREPHINATION FOR CHRONIC SUBDURAL HEMATOMA

　抄録　慢性硬膜下血腫術後に発症したsubdural tension pneumocephalusの1症例を報告した。術後に発症する比較的稀な合併症であるtension pneumocephalusの報告例を分折し，慢性硬膜下血腫術後のsubdural tension pneumocephalusの発生機序を考察した。脳室ドレナージ・髄液シャント手術や坐位での後頭蓋窩手術の術後にみられるtensionpn eumocephalusの発生機序には多くの因子が関与しているが，ball-valve機構の形成を伴う外界との交通と髄液の多量の流出が主な要因であろうと考えられる。しかし，自験例のごとく慢性硬膜下血腫術後のsubdural tension pneumocephalusの場合は，さらに頭蓋内容物の容積増や体温による空気の膨張なども重要な因子であろうと推測した。

Symptomatic tension pneumocephalus developed after an evacuation of chronic subdural hematoma is reported. In this 71-year-old man, a rapid dete-rioration of consciousness was noted 3 days after a trephination for bilateral chronic subdural he-matomas. An evacuation of hematoma was perform-ed under a local anesthesia, and the peropera-tive and immediate postoperative course was un-eventful. Subdural tension pneumocephalus was confirmed by typical CT findings and treated by re-trephination and drainage.

The literature on the tension subdural pneumo-cephalus was reviewed, and the mechanism of its development was briefly discussed.