小河内 芳彦¹, 寉田 さやか¹, 山寺 陽一²

Yoshihiko OGAUCHI¹, Sayaka TSURUDA¹, Youichi YAMADERA²

¹財団法人山梨厚生会山梨厚生病院検査部, ²財団法人山梨厚生会山梨厚生病院外科

¹Medical Laboratory, Yamanashi Kosei Hospital, ²Department of Sugery, Yamanashi Kosei Hospital

キーワード : ultrasonography, fat necrosis, pseudotumor

症例：患者は69歳男性，健診後の精査目的のため来院．超音波検査にて右上腹部に無症状な腫瘤性病変を指摘．腫瘤径は47mm×35mm，内部は均一で右腎皮質に比して高エコーを呈した．後方エコーは不変から増強，境界は明瞭で辺縁に低エコー帯を認めた．内部の血流は認めなかった．術後の病理組織学的検査では，線維性被膜に覆われた脂肪壊死と診断された．考察：偽腫瘍性脂肪壊死は発見時の病期の違いから質的診断が困難と思われる．しかし，腸間膜内において内部に血流の認めない被膜形成を伴う腫瘤性病変を発見した場合は，この種の脂肪壊死も念頭に置くべきであろう．また，癒着の度合いや範囲により術式が変化する可能性もあるため，腫瘤の可動性をリアルタイムに観察出来る超音波検査の利点を活用し，癒着の有無や範囲を検索することが重要であると思われた．

The case: The patient is a 69-year old man. Ultrasonography (US) revealed a 47 x 35 mm space-occupying lesion (SOL) in the upper right quadrant of his abdomen. The internal echo pattern was homogeneous and more hyperechoic than the kidney cortex. The posterior echo was accentuated, and a well-defined border and a hypoechoic margin were observed. Color Doppler imaging detected no internal blood flow.After surgery, pathological examination of the mass lead to a diagnosis of fat necrosis covered with a fibrous capsule. Discussion: Concerning pseudotumoral fat necrosis, a qualitative diagnosis is made by differences in stage of disease at time of discovery. If, however, a mass with a fibrous cap and no internal blood flow is detected in the mesentery, the possibility of this kind of fat necrosis should be born in mind. Further, because surgical methods may vary depending on degree or range of adhesion, we suggest that it is more important to investigate existence, degree, or range of adhesion by utilizing the greatest advantage of ultrasound, namely the possibility of real-time observation of mass movement.