内視鏡による高周波胃ポリペクトミー

Endoscopic Gastric Polypectomy with High Frequency Currents

　最近数年間，胃内視鏡器械は胃生検の精度向上を目指して，著しくその精巧さを増してきている．それにつれて，胃生検技術を応用して，胃内において病変の病態生理の検査や処置ないし治療が試みられている．昭和44年常岡ら¹⁾²⁾は胃生検用ファイバースコープを用い，鉗子孔にワイヤーループを通して胃ポリープの機械的な絞約切断法を発表した．この方法は内視鏡的治療法のパイオニアとして注目を集めた．近年，ポリープの内視鏡的切断に高周波電流を応用することにより，出血防止対策が一歩進んだため，大腸ポリープ³⁾を始めとして，消化管の内視鏡的ポリープに対する治療法⁴⁾が次第に広く試みられて来ている^5)～8)．しかし，現時点においては出血対策及び偶発症予防対策は充分であるといえない．一般にルーチン化されるためには更に出血防止対策⁹⁾が進歩しなければならない．

　なお著者は胃ポリペクトミーの言葉をポリープ切断の術式と解釈し，この方法によって，一定条件をそなえた異型上皮や隆起性胃癌をも対象にしうると考えている．

　Progress of endoscopic diagnosis along with improved instruments has now made it possible to excise polyp of the colon by means of high frequency current. Over the years the author has studied the application of this technique to the excision of gastric polyp, and now it has become a safe procedure and the technique is clinically well established. In this paper are put forth general remarks about endoscopic polypectomy of the stomach with some reference to endoscopic excision of duodenal polyp that is now also made possible.

　At the outset the author contrived a transformer generating high frequency current solely for the use of endoscope. The transformer was characterized by heightened safety and effectiveness and also by guarding against high tension current with the adoption of high frequency blend waves. Trial manufacture has also been made of several kinds of loop wire for excision, rod wire for cautery and forceps for excision and catching the severed polyp, with their merits and demerits compared with one another. Furthermore, side-viewing 2-channel gastrofiberscope of large caliber for treatment has been devised by the author together with other fiberscopes for treatment. Their relative merits have been appraised.

　Clinical results obtained by the above-mentioned instruments are summarized as follows: For guarding against massive bleeding, it is safer to confine this maneuver to subpedunculated or pedunculated polyp. Broad-based polyp should be avoided. The size of the stalk's basis is more important than the greatest diameter of the polyp itself. Too strong current should naturally be avoided because of increasing chance of bleeding, deepening of ulcer or perforation. The site of shaving off the stalk should be several mm away from the mucosal surface. If too close, ulcer may develop over the mark of injury. For this purpose, 2-channelled side-view fiberscope of larger caliber is needed. When the injured part is either flat or eroded one day after high frequency excision, the mean time for its epithelialization is 11 days. In shallow ulcer, it is 23 days, and in deeper ulcer, 33 days. It is of great interest that as compared with other preventive measures of gastric ulcer the days needed for. healing of ulcer cauterized with high frequency current are far shorter.

　The author is now of the opinion that as gastric polypectomy represents only a curative procedure, atypical epithelium and gastric cancer of protruding type can also be subjected to the present procedure.