胃潰瘍の超音波内視鏡所見と病理所見との対比

A Comparison between Endoscopic Ultrasonography and Histology of Gastric Ulcer in the Resected Stomach

要旨　ホルマリン固定切除胃を用い，超音波内視鏡検査（以下EUSと略）による胃潰瘍の深さの判定を試みた．まず，EUSでの胃潰瘍の深さに対する診断基準を作るため，切除標本にUl-Ⅱ，Ⅲ，Ⅳに相当する組織欠損を作製し，これを水浸下で走査しEUS像を得た．潰瘍瘢痕は作製が困難であったため，それらの典型的な組織像からEUS像を類推し，EUSによる潰瘍の深さのシェーマを作成した．この診断基準に沿って切除標本31症例41病変に対しEUSを行ったところ，開放性潰瘍では90％の正診率が得られたが潰瘍瘢痕のそれは71.4％であった．誤診例の検討では層構造の描出が困難な場合と，線維症および筋線維の錯綜のための層構造の不明瞭化による場合があり，線維症によるエコーレベルの変化を更に検討することが今後の課題と考えられた．

　We tried to analyze the structure of gastric ulcers by endoscopic ultrasonography (EUS) . In order to obtain a diagnostic standard, resected stomachs set up artificially in a natural position so that EUS could be performed on the open ulcers (Ul-Ⅱo, Ul-Ⅲo, and Ul-Ⅳo) within them. Diagnostic standard of healed ulcers (Ul-Ⅱs, Ul-Ⅲs, and Ul-Ⅳs) was based on established histological findings because of the impossibility of making healed ulcer models in the resected stomachs. EUS was performed in 31 resected stomachs with 41 peptic ulcers and the diagnoses by EUS were compared with histological findings. The diagnostic accuracy by EUS was 90% (18/20) in guaging depth of open ulcers, and 71.4% (15/21) in that of healed ulcers. The misdiagnoses by EUS resulted from obscure layer structure, especially the outer low echoic layer. It also arose in cases of fibrosis in the muscularis propria, and from the difficulty of detecting all of the layers.