消化管のPolypectomyの現況と問題点―胃（特に高周波スネアー法と電気的効果について）

Endoscopic Surgery (Stomach): Present state and problems of gastric polypectomy; with special reference to the high-frequency current snare method and its electric effect

　胃polypectomyは，部分生検にかわる完全生険とポリープの切除治療との2つの観点から1968年本邦で創始されて以来^1～4)，ファイバースコープの進歩開発と共に観察し得る全消化管のpolypectomyが可能となった．当初ワイヤーループによる押切り法で始まったpolypectomyは，危惧せられた出血の対策として高周波電流を応用した凝固止血・切断の手順による高周波スネアー法が今では専ら普及している．胃ポリープの性格分類も明らかになり⁹⁾，内視鏡的polypectomyは，従来の胃切除または胃の部分切除にかわり，患者にとって侵襲の極めて少ない安全な治療法の位置づけがなされた⁵⁾．

　しかるに，近年でも大出血，穿孔等の偶発症が見られ開腹例や死亡例の報告もある^6,7)．押切り法には見られなかった高周波電流を用いたための新たな問題がある．実施者の高周波電流およびスネアーの扱い方と偶発症の解決を含め，高周波スネアー法を中心に内視鏡的pclypectomyの実際について述べる．

　Since the introduction of high-frequency current snare coupled with a measure to counter bleeding, endoscopic polypectomy has replaced gastrectomy hitherto considered essential. This new method is now firmly established as a secure treatment for gastric polyp with far less risk to the patients. Nonetheless, from time to time we would come across reports of accidental bleeding of serious degree or even perforation of the gastric wall, at times necessitating emergency laparotomy or even causing death from loss of blood. Introduction of high-frequency current itself has bred a new problem.

　In order to lessen untoward complications in endoscopic polypectomy, we have made experiments on pieces of meat using high-frequency snare method. For high-frequency generator, we have used Machida HC-80L with mixed wave type. Good results with electrocoagulation and removal of the polyps were obtained by reducing the area of cutting section through more tight closing made possible by the use of wires of smaller caliber and augmented electric current.

　In clinical applications, basic maneuvers for the secure removal of the polyps were tight snare closing, fixing and current application. As a rule, electricity was turned on for two seconds. Our yardsticks for cutting of the polyp were white belt, bubbles or emmission of smoke seen around a part of the snare. Complete cutting of the polyp was finally confirmed by response of the grip at hand and gentle breakaway of the snare.

　Here are illustrated instruments necessary for hemostatic procedure. Also is showh effectiveness of stanching by compression with forceps and hemostatic procedure by coagulation with the use of a flat tip coagulator. For polyps of greater dimensions in which larger or more numerous blood vessels were suspected to interfere polypectomy, hemostatic procedure with ligature was effective as a pre-operative step to polyp cutting.

　For flat polyp, employment of two forceps or partition cutting of the polyp were proved successful.

　High-frequency snare method is a safe method for polypectomy, provided that the means of adequate hemostatic procedure is always available at hand. Emphasis is put on the fact that most of accidental complications could be prevented if the examiners be familiar with the characteristics of high-frequency current and pay great attention to how to manipulate the snare as it should be done.