胃と腸54巻2号

2019年02月発行

今月の主題 胃・十二指腸内視鏡拡大観察の基本と最新知見

主題

胃癌診断体系以外の有用な所見—white opaque substance（WOS）

著者： 中西宏佳¹ 土山寿志¹

所属機関： ¹石川県立中央病院消化器内科

ページ範囲：P.202 - P.205

文献概要

要旨●白色不透明物質（WOS）は，NBI併用拡大内視鏡で明瞭に視覚化される粘膜表層の白色物質である．慢性胃炎粘膜の腸上皮化生，胃の上皮性腫瘍にしばしば認められる．WOSの正体は，上皮内，上皮下に集積した微小な脂肪滴であり，内視鏡からの投射光が強く散乱または反射されるために白色として認識される．WOSがあると上皮下の微小血管まで投射光が到達しないため，血管の視認性が低下する．WOSの形態学的特徴の違い（regular/irregular）は，癌と腺腫の鑑別に有用な指標となる．

参考文献

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