胸部単純X線で認められた限局的横隔膜挙上（CTではeventration）の症例において認められた横隔膜と肝表面との間の腹腔内脂肪の1例

Interposition of fatty tissue between the diaphragm and liver in a case of diaphragmatic eventration

胸部X線で横隔膜挙上が認められた場合の鑑別診断にはいくつかある。その中でも限局的横隔膜挙上の鑑別診断にはいろいろあり，胸部X線のみではこれらの鑑別は難しいと考える。すなわち横隔膜が局所的に挙上している場合は鑑別として肝腫瘍の横隔膜面への突出，肝膿瘍，横隔膜弛緩症（eventration），横隔膜下膿瘍，横隔膜腫瘍，横隔膜ヘルニア，肺炎，肺下胸水などが挙げられ，これらの鑑別にはUSまたはCTが必要である。

A 41-year-old obese man was screened by a chest x-ray, which showed localized elevation or scalloping of the diaphragm, suggesting so-called diaphragm-liver hernia. CT of the chest showed localized elevation of a thin diaphragm, consistent with diaphragmatic eventration. Fatty tissue was found between the diaphragm and the liver in this case. The fatty tissue was continuous to the whole intraperitoneal fatty tissue.

This kind of findings has not been observed in 8 patients with eventration among 14,020 screening chest x-rays in our institution.

This kind of findings may be seen in future because obesity has been more frequently observed recently in Japan.