5) 大腸―大腸腫瘍性病変に対して適切な治療方針に導く拡大内視鏡観察のコツを中心に

Know-How for Magnifying Observation : Photography, How to Focus, How to Use Different Pigments, Etc.―Mainly the Know-how for Magnifying Endoscopic Observation to Decide Appropriate Therapeutic Strategy Against Neoplastic Colorectal Lesion

要旨　日常臨床の場で拡大内視鏡観察・撮影を良好な条件下で行うための手順と良い写真撮影を行う工夫および色素の使い分けなどについて症例の提示も含めて解説をした．すなわち，まず病変の洗浄から始まり，通常観察では病変全体像や病変周囲健常粘膜の性状の把握が大切である．次に行う色素観察では腺管開口部内に色素液を貯留させて腺管の開口部形態（pit pattern）を診断するコントラスト法（IIIL型やIV型pit patternを示す隆起型や表面隆起型病変の腫瘍か非腫瘍かの質的診断に最適）と腺管開口部は染色されず不染部として描出され，この不染部の形態を観察しpit pattern診断を行う染色法（コントラスト法で観察が困難なIIIs型やV型pit patternを明瞭に描出させることができる）の使い分けが大切である．染色法（クリスタルバイオレット染色下）の拡大観察では，特に通常・色素（インジゴカルミン撒布）内視鏡観察にてSM深部浸潤癌を疑う部分（領域性）の正確なpit pattern診断がその病変の治療方針決定に重要となるため，その領域性全体のpit patternを把握できる弱～中拡大像をよく観察・撮影し，内視鏡像・実体顕微鏡像・病理組織像との一対一対応ができるような内視鏡観察・撮影をするためのコツについて解説をした．

　The procedure for magnifying endoscopic observation and photography under good conditions in daily clinical practice is interpreted through example cases related to ingenuity for good photography and how to use different pigments. Namely, the procedure starts from cleaning the lesion, and in ordinary observation, it is important to grasp the entire picture of the lesion and the status of the peri-lesion normal mucosa. In pigments of observation, it is important to separately use the contrast method in which the gland duct pit pattern is diagnosed by retention of a pigment fluid in the gland duct pit (suitable for qualitative diagnosis of protruding tumors with a pit pattern of Type-IIIL or Type-IV, neoplastic or non-neoplastic) and the staining method in which the gland duct pit is visualized as the non-stained part and the pit pattern is diagnosed by observing the non-stained part (a pit of Type-IIIs or Type V which can hardly be observed by the contrast method can be clearly visualized). In magnifying observation using the staining method (under crystal violet staining), the exact pit pattern diagnosis of the part at which SM deep invasion is suspected (range-type) in conventional colonoscopy or the chromoendoscopy (indigo-carmine spray) is important for deciding the therapeutic strategy against the lesion concerned. There is an explanation of the know-how necessary for the sufficient observation and photography of a low power image enabling a grasp of the pit pattern througout the entire area. In addition there is explanation of the endoscopic observation/photography needed to obtain correspondence between the endoscopic image, stereomicroscopic image and histopathological image.