拡大内視鏡が慢性胃炎の診断をどう変えたか

Magnifying Endoscopic Diagnosis for Gastric Intestinal Metaplasia

要旨●胃癌リスクに応じた上部消化管内視鏡のサーベイランス間隔を考慮するうえで，腸上皮化生の診断は重要である．腸上皮化生の存在診断に関しては，有用な拡大観察所見が複数報告されている一方で，内視鏡画像の鮮明化に伴い非拡大観察での診断能も向上している．腸上皮化生のうち不完全型腸上皮化生は完全型腸上皮化生に比べ胃癌発生リスクがより高いとする報告が多く，筆者らはNBI併用の拡大観察を用い，微細粘膜構造と腸上皮化生サブタイプの関連性を検討した．NBI拡大観察で畝状の表面構造が優勢である腸上皮化生は，不完全型である割合が高い傾向にあったが，正確な鑑別は困難であった．

　The diagnosis of gastric intestinal metaplasia is essential to consider the surveillance interval of gastroscopy depending on the risk of gastric cancer.

　Regarding the diagnosis of intestinal metaplasia, several useful findings with magnifying endoscopy have been reported. In addition, high-resolution endoscopic imaging has enhanced the diagnostic ability of non-magnifying endoscopy.

　Regarding intestinal metaplasia, research has revealed that incomplete intestinal metaplasia poses a higher risk of gastric cancer occurrence than complete intestinal metaplasia.

　We examined the association between the microsurface pattern of the corpus mucosa and the subtype of intestinal metaplasia using ME-NBI（magnifying endoscopy combined with narrow band imaging）.

　In ME-NBI, the proportion of incomplete intestinal metaplasia tends to be high in the region with dominant ridge crypt openings ; however, this was not a precise method of discrimination.