機能面からみた大腸憩室症（大腸憩室疾患）

A Study of Colonic Diverticulum from the Point of its Function

　1973年以前のわが国の大腸憩室の統計^1)～5)をみると発見率が5％をこえている報告はない．当時は比較的少ない大腸疾患と考えられていたし，臨床的にもそれほど重要視されない疾患であったといえよう．ところが，近年大腸疾患に対する関心が急速に高まったこと，大腸のX線検査法の手技上の根本的な改良と読影能力の向上などのおかげで，大腸憩室の発見率は，注腸X線検査総数の5～17.3％^6)～8)と，むしろもっともありふれて見かける大腸疾患の1つとなった．また，これまで発表されている諸家の報告のうちで信頼できるものをみても，検査手技の向上だけが増加の原因でなく，確実に増加傾向が認められるようで，欧米における発生頻度5.7～25％^9)～11)にせまろうとしている．

　一方，これらの大腸憩室疾患（diverticular disease）の50～78.5％が，なんらかの臨床症状を伴っている^12)～15)とされており，臨床の場においてももっともっと重要視しなければならないと認識が改められつつある．

　The occurrence of colonic diverticulum was thought to be relatively low in Japan. But according to recent statistics, its rate of occurrence has been reported as approximately 10% and thus, colonic diverticulum has become a common disease. However, its pathogenesis and characteristics are not yet sufficiently elucidated. The reason being that although much histological and pathological researches are conducted, references from the point of motor function are in slow progress due to the anatomical peculiarity of the colon.

　Recently, measurement of colonic intraluminal pressure using the endoscopic method has been devised and measurement of the intraluminal pressure on the deep colon has been made possible. Adopting this method, we have studied the colonic intraluminal pressure patterns of IBS patients. In addition, a study of the comparison of the intraluminal pressure curve of IBS patients and diverticula patients was made. Because there are a few case reports, our findings can only be inferences. But nevertheless, the intraluminal pressure curve indicates that in those sections with subjective symptons and where diverticulum exists, increase in the intraluminal pressure and also abnormal pattern are observed. In the area with no indication of the development of the disease, the curve was close to that of normal intraluminal pressure.

　Studying these data and also reports indicating the appearance of diverticulum in a long range period observation of IBS patients, it can be inferred that IBS may develop into diverticulum. In the future, researches in characteristics and causes of colonic diverticulum will be enhanced by approaching it from the view of its function and also through histological study.