Barrett食道の内視鏡診断

Endoscopic Diagnosis of Barrett's Esophagus

要旨　前癌病変として知られるBarrett食道の内視鏡像について検討した．多くの症例は扁平上皮と円柱上皮の間に食道炎の介在を認めたが，経過の長い症例ではその移行は明瞭であった．粘膜面は周囲の炎症の程度により発赤肥厚の中に萎縮した扁平上皮の遺残島を認めたり，淡い萎縮性の発赤として観察され，一様ではない．血管透見は炎症の進行中の症例では見られることは少ない．電子スコープの近接観察では胃小窩模様の観察ができる．Barrett上皮を選択的に染色する方法はないが，crystal violetが今後期待される色素剤である．Barrett上皮内のdysplasia，carcinomaへの初期変化を捉えるにはこまめな生検が大切である．また一度形成された食道の円柱上皮は逆流防止手術をしても完全消失は期待できない．

　Repairing process of esophagitis induces columnar epithelialization in a pin-point area, then spreading gradually. We have already proposed to classify this histological change into Barrett's esophagus, which involves the mucosa circumferentially, and Barrett's epithelium, which does not involve the mucosa circumferentially. Both Barrett's esophagus and epithelium are well known as precancerous conditions.

　We report here endoscopic findings associated with these mucosal changes. Between the areas of normal squamous epithelium and columnar change, in many cases, is interposed mucosal changes of esophagitis which is clearly demarcated especially in chronic cases. There were such various mucosal changes of esophagitis as residual islands of squamous epithelium in a reddish hypertrophic lesion and atrophic change with reddish tinge. In cases in which inflammation is in progress, vascular pattern was seldom seen. Close-up view using an electronic endoscopy revealed gastric alveolus pattern. Although no dye is so far known to selectively stain Barrett's epithelium, Crystal Violet seems promising.

　Out of 236 cases of postoperative esophagitis 21 cases of columnar epithelialization and 2 cases of cancer of the esophagus were detected. Thus, it is important to perform periodic examination to detect early cancer or dysplasia arising from Barrett's epithelium, even after surgical repair of reflux esophagitis.