胃前壁病変の内視鏡診断

Endoscopic Diagnosis of Lesions on the Anterior Wall

　胃の後壁病変のX線診断に関しては，二重造影法の開発によりほぼ完成されたと言っても過言ではないが，前壁病変に関しては腹臥位二重造影法あるいは圧迫検査によって目ざましい向上をみたとはいえ，技術的な問題も含めて未だに困難が多いことは否めない事実である．これに反して，内視鏡検査では前壁はレンズ面からの良好な観察距離が容易に保たれ，広い視野での観察が可能な部位である．このことから考えても，前壁病変については内視鏡検査が優れた診断能を発揮し，とくに前壁病変の存在診断に関しては極めて能率の良い検査法であることが首肯されるのである．したがって，良好な内視鏡的条件で，すなわち，病変部を十分に伸展させた状態のもとに正面直上方向，ならびに斜方向からの観察が適確な距離で行なわれておりさえすれば，前壁病変の診断に関しては鑑別診断すなわち観察された病変の内視鏡的質診断のみが残された問題として登場するはずである．しかし，実際問題としては，上述した観察あるいは撮影が十分に行なわれていたか否かが重要な問題であり，本稿ではかかる観点から下記の問題点について，前壁病変の内視鏡診断を考察してみたい．

　Diagnostic capability of endoscopy in the lesions on the anterior wall of the stomach has been studied on the basis of nine cases published in this journal for the past five years as well as of 33 of gastric resection performed in the author's department. The results are as follows:

1. All of nine cases of lesions on the anterior wall reported in the “Stomach and Intestine” were correctly diagnosed by preoperative endoscopy.

2. The resected stomach opened along the greater curvature was divided equally into eight parts in the longuitudinal axis as in Fig. 1, and the upper second and third sections were considered as belonging to the anterior wall. Consequently, any lesion localized within these sections was regarded as a lesion on the anterior wall.

3. Of 40 lesions on the anterior wall, 28 (70%) were detected at the initial x-ray. The existence diagnosis of a lesion by endoscopy was accurate in 36 lesions (90%).

4. Two lesions (5 %) in the prepyoric region eluded both x-ray and endoscopy. Another two lesions (5 %) in the oral part of the stomach were found by x-ray but overlooked by endoscopy.

5. Excavated lesions on the anterior wall are often visualized greater than they really are because the mucosa around the lesion tends to hang down, so that the nature of the lesion as well as depht of cancer invasion is often over-estimated. The same applies to protruding lesions as well in evaluating their height and surface irregularity.

6. Not only for lesions on the anterior wall but also for those in other segments of the stomach, endoscopy is still confronted with many difficulties, such as qualitaive diagnosis of small protruding lesions and correct estimation of depth invasion of cancer. There is still many a lesion to which coemployment of biopsy is indispensable for its qualitative diagnosis.