狭窄を来す小腸疾患の診断─CT・MRI診断の立場から

Diagnosis of Small Intestine Disease with Stricture Formation, on CT and MRI

要旨●小腸に狭窄を来す疾患は原因別に炎症性狭窄と腫瘍による狭窄に大きく分けられる．他の消化管に比べると小腸の腫瘍や炎症はまれである．小腸病変は上部，下部消化管内視鏡検査や造影検査では観察することができず，診断までに時間がかかることが多い．炎症性狭窄ではイレウスや消化管穿孔などの重篤な結果となることもあり，早期の発見が重要である．近年カプセル内視鏡やバルーン内視鏡の登場により，小腸の評価でも内視鏡が選択肢のひとつに含まれるようになった．しかし，CTやMRIの技術進歩もめざましく，腸管壁や腸間膜血管の評価も可能となっている．本稿ではCT・MRIの立場から狭窄を伴う小腸疾患の診断へのアプローチについて症例を提示しながら概説する．

　The causes of small intestine disease with stricture formation are roughly divided as follows：inflammatory disease and tumorous stenosis. Small intestine inflammatory disease and tumorous stenosis are rare compared with other gastrointestinal tract diseases. Diagnosis of small intestine stenotic disease cannot be observed on the commonly performed radiographic and endoscopic examinations. It often takes more time to diagnose small intestine disease. Inflammatory stenosis sometimes has severe consequences, such as ileus and intestinal perforations; thus, early diagnosis is important. Recently, capsule and balloon endoscopy evaluations of the small intestine have been included. However, technological progress in CT（computed tomography）and MRI（magnetic resonance imaging）is remarkable, and it has become possible to evaluate the intestinal wall and mesenteric vessels. Here we present a discussion of cases in which CT and MRI demonstrated stenosis resulting in intestinal lesions.