慢性硬膜下血腫と鑑別が困難であった硬膜下膿瘍の1例  [in Japanese] Subdural Empyema Indistinguishable from Chronic Subdural Hematoma: A Case Report  [in Japanese]

症例は62歳の男性.左上肢の脱力と痙攣発作で当院に救急搬送された.頭部CT・MRI(DWIを含む)上,右大脳半球円蓋部に硬膜下液貯留を認め,血液生化学検査では炎症徴候を認めなかった.当初は慢性硬膜下血腫と診断され,第1病日に穿頭術が行われたが,術中硬膜下腔より膿の排出を認め,硬膜下膿瘍と診断された.その後,抗生物質による治療を行ったが,最終的には開頭術による膿瘍除去を必要とした.本例はいわゆる感染性硬膜下血腫であった可能性が高い.本例のように硬膜下膿瘍は,慢性期においては時に慢性硬膜下血腫ときわめて類似した所見を呈する場合があり,慎重に診断を進めることが必要と思われる.

We present a case of subdural empyema which was indistinguishable from chronic subdural hematoma. A 62-year-old male was admitted to our hospital because of general convulsion and motor weakness of the left upper extremity. His laboratory data indicated no signs of infection. Computed tomography (CT) and magnetic resonance (MR) imaging (including diffusion weighted imaging) showed a subdural fluid collection in the right convexity, which resembled a chronic subdural hematoma. At first, he was diagnosed with chronic subdural hematoma, and was treated with burr hole surgery. However, pus was aspirated from the subdural space during the operation, and thus the diagnosis of subdural empyema was confirmed. Although antibiotic therapy was performed after surgery, the subdural empyema eventually necessitated surgical evacuation by craniotomy. He was discharged without any apparent neurological deficits. It is presumed that this was a case of so-called "infected subdural hematoma". This case indicates that subdural empyemas in the chronic phase may present with extremely similar findings to chronic subdural hematomas. The differentiation between subdural empyema and chronic subdural hematoma should be carefully conducted.