超音波内視鏡からみたH2受容体拮抗薬療法の限界

Limitation of H2-Receptor Antagonist Therapy of Peptic Ulcer Judging from Endoscopic Ultrasonography (EUS)

要旨　胃潰瘍症例31例34病変を対象とし，胃潰瘍の治癒過程におけるEUS像の変化について検討した．胃潰瘍のEUS像は潰瘍の治癒に従い陥凹部の幅，深さの減少，陥凹底部の低エコーの領域の縮小が認められた．Ul-Ⅳの潰瘍のEUS像は陥凹底部の低エコーの領域と潰瘍辺縁における第2，4層の収束所見により4型に分類でき，各エコーtypeの間に移行が認められた．難治性潰瘍はEUSにてUl-Ⅳの潰瘍で，潰瘍の辺縁で第2層と第4層が収束し，潰瘍底は厚い低エコーの領域により取り囲まれていた．すなわち，潰瘍の難治化には粘膜筋板と固有筋層の融合および潰瘍底の厚い線維層の所見が関与していた．

　A study was made on the healing process of gastric ulcer using EUS in 31 cases. The ulcers were observed to decrease in width and depth as well as the low echo area in ulcer base as they became healed. The ultrasonographic appearance of Ul-Ⅳ ulcer was classified into four types based on the findings of the low echo area in ulcer base (homogenous or biphasic) and of the fusion of the second and fourth layer at the ulcer edge (fusion or non-fusion). These four types were abbreviated Hn, Hf, Bn and Bf. Ul-Ⅱ ulcer tended to contract faster than Ul-Ⅳ ulcer. Contracion rate of the width of low echo area in ulcer base was slower than that of the width of gastric ulcer crater. Thus, it is suggested that the inner change of ulcer persists even after the superficial change has healed. The intractability of gastric ulcer to H₂-receptor antagonist therapy depended on the existence of the fusion of muscularis mucosa and muscularis propria and the thick subserosal fibrosis in ulcer base. Such an intractability of gastric ulcer can be diagnosed by EUS more effectively than any other methods.