拡大内視鏡

Magnifying Endoscopy

要旨　拡大内視鏡の現況について，その有用性と限界を混じえ述べた．拡大観察の有用性は高いものの，あまりにも専門的になりすぎたきらいがある．拡大倍率と操作性は相反する関係にあり，一般臨床に普及させるためには20倍以上の高倍率を有する機種のみでなく5倍程度の低倍率であっても操作性の良好な機種が必要である．また，電子内視鏡の利点ともいえる画像処理を行うことにより主観的診断から客観的診断へと発展する可能性がある．

　A magnifying endoscopic examination is defined as an examination which enables one to observe gastric or colonic pits and villi in details. Gastric or colonic pits are 30 to 50 μm and small intestinal villi are 0.2 to 1 mm in size. However, the regenerative epithelium around a gastric ulcer is 30 to 300μm in sine. Twenty power magnification would be necessary to observe the fine mucosal findings of the alimentary tract. Therefore, a 20 power magnified view is defined as a magnifying observation and under 20 power magnified one is defined as a close-up observation. There have been many studies concerning the effectiveness of a magnifying observation. However, a magnifying observation is not regarded as a routine endoscopic exmination yet. We demonstrate the validities and restrictions of a magnifying endoscopic examination and mention the future prospect of this examination.