直腸下部病変の内視鏡診断

Endoscopic Diagnosis of the Lower Rectum and Anal Canal

要旨　直腸下部と肛門管の一部の内視鏡的観察について述べた．他の分節と同様に挿入時，抜去時ともに観察すべきであるが，ファイバースコープや電子内視鏡による通常観察には限界があった．そのために反転観察を追加した．反転手技はほぼ全例に施行しえたが，癌浸潤，浮腫や線維化のために展開が不良な例では不能であり，また肛門括約機能の低下例では不十分となった．通常，後壁を除いて良好な観察が得られた．大部分の疾患で反転観察は有用であったが，Crohn病では意義が少なかった．また，この部のポリープや癌からの生検やポリペクトミーには肛門鏡を活用するほうが簡便であった．色素法は有用となろうが，この部においては更に検討が必要となろう．

　Endoscopic observation of the lower part of the rectum and proximal part of anal canal was discussed. As in the other segments of the bowel, endoscopic observation should be performed not only during withdrawal but also during insertion of the instrument. The usual manner, however, was often insufficient to obtain a clear view of these parts. For that reason, the U-turn technique was added. This could be performed in all cases except when there was poor distension of the lower part of the rectum due to cancer invasion or inflammatory process, and when observation was difficult because of decreased sphincter tone of the anus. Endoscopic exploration by this procedure enabled complete observation of all except one part of the posterior wall. It proved helpful in the discovery of most lesions. For biopsy of tissue from polyp and cancer and for polypectomy, on the other hand, the rigid anoscope was also useful.

　In conclusion, endoscopic diagnosis of the lower part of the rectum and proximal part of the anal canal should be performed using various techniques and instruments in order to obtain complete results.