Method: 30% trichloroacetic acid solution was used to cauterize the inner wall tissue.The residual and necrotic substances were removed to make the wounds clean, then MEBO was applied locally.

• 方法:采用30%25三氯醋酸烧灼瘘道内壁组织,再去除残渣坏死物,以达新鲜创面;