自制内镜注射针经喉镜注射氢氧化钠构建兔食管良性狭窄模型

The establishment of benign esophageal stricture model in rabbits through laryngoscopic injection of NaOH with a self-made endoscopy injection needle

目的探讨一种新的兔食管良性狭窄模型构建方法——自制内镜注射针经喉镜注射氢氧化钠（NaOH）构建食管良性狭窄模型，为支架置入体内相关介入研究提供实验基础。方法自制注射针：将一次性胃镜注射针外层导管去除，取含针头端长约70mm内芯导管。将针头剪至2mm长并磨成斜坡状，去除针柄及部分塑料管，然后接上内芯导管无针头端。选择2—3奴健康兔10只，3％戊巴比妥（1ml/kg）经耳缘静脉注射麻醉，左侧卧位固定于DSA操作台；透视下将泥鳅导丝插入胃腔，8mm×40mm球囊置于食管下段贲门处，喉镜下距球囊近端约1cm处选取环周4个点，经自制内镜注射针分别注入1．5％NaOH0．25ml。术后2周和4周分别作喉镜及造影检查；术后4周处死实验兔，取材作组织病理学检查。结果术后2周喉镜检查显示食管中下段溃疡形成。无明显狭窄；造影显示食管中下段管壁不光整。术后4周喉镜显示食管中下段瘢痕形成、食管狭窄；造影显示食管中下段局部狭窄：组织病理学检查提示局部溃疡、黏膜下层增厚、瘢痕形成。食管管径狭窄率为平均49．54％（44．89％～56.65%）；狭窄长度造影测量为平均18．0mm（14．6-22．8mm），标本测量为平均16．3mm（13．1-21．1mm）。结论自制内镜注射针经喉镜注射1．5％NaOH可成功构建兔食管良性狭窄模型,方法简单易行,狭窄程度和部位易控。

Objective To discuss a new method for the establishment of benign esophageal stricture in rabbits, i.e. through laryngoscopie injection of sodium hydroxide （NaOH） with a self-made endoscopy injection needle to establish benign esophageal stricture model, in order to provide experimental basis for the interventional studies associated with stent implantation, Methods The self-made endoscopic injection needle was prepared as follows. The outer layer of a disposable gastroscopy injection needle was removed in order to obtain an ~out 70 mm-length inner core catheter with needle tip, this needle tip was cut to 2 ram long and was ground to form a slope shape. The needle handle and part of its plastic tube were cut off, then it was connected with the needle-free end of the inner core catheter, Ten healthy rabbits of 2-3 kg body weight were selected, 3% pentobarbital （1 ml/kg） was injeeted via ear-margin vein to make general anesthesia. The experimental rabbit was fixed on the DSA operating table in left lateral recumbent position. Under fluoroscopic guidance, the guide wire was inserted into the gastric cavity, an 8 mm by 40 mm balloon was placed at the lower segment of esophagus near the cardia. Under laryngoscopic observation, 4 points around the esophageal lumen, which were about one cm from the proximal end of the balloon, were selected to separately receive the injection of 0.25 ml of 1.5% NaOH through the self-made endoscopic injection needle, Laryngoscopeexamination and esophagography were performed at 2 and 4 weeks after the injection. The experimental rabbits were sacrificed at 4 weeks after the treatment, and the tissue samples were collected for pathological examination. Results Laryngoscope examination at two weeks after operation showed that ulceration was formed at the middle and lower part of the esophagus, but no obvious stricture was observed; esophagography revealed that the mucous membrane of the middle and lower part of esophagus became rough. Laryngoscope examination at four weeks after treatment indicated that there were scar formation and esophageal stenosis at the middle and lower part of the esophagus; esophagography showed that local stenosis was formed at the middle and lower part of the esophagus. Histopathological examination revealed that there were local ulcer, submucosal thickening and scar formation. The mean esophageal stenosis rate was 49.54% （44.89%-56.65%） ; the mean length of the stricture measured on esophagographs was 18.0 mm（ 14.6 mm-22.8 mm）, which was 16.3 mm（13.1 mm-21.1 mm） when measured on the specimens. Conclusion Laryngoscopic injection of 1.5% NaOH with a self-made endoscopy injection needle can successfully establish benign esophageal stricture model in rabbits. This method is simple and easy to operate, besides, the degree and location of the stenosis can he easily controlled.