Objective: To establish a New Zealand rabbit animal model of laryngopharyngeal reflux disease (LPRD) using esophageal balloon together with metal internal stent dilation and to investigate the changes of mucosa. Methods: 20 New Zealand rabbits were randomly divided into experimental group and control group, with 10 in each group. Balloon dilatation and metal internal stent dilation were carried out in experimental group to reproduce the animal model of LPRD.The middle of balloon was placed at the lower esophageal sphincter (LES) while the stent was placed at the upper esophageal sphincter (UES). The guide wire was placed in the control group, but the balloon was not expanded and the stent was not placed. The general condition, pH value of hypopharynx, laryngeal histopathology and changes of pepsin content of New Zealand rabbits were observed regularly. The difference between experimental group and control group was compared. Results: The 24-hour Dx-pH monitoring results showed that the number of reflux episodes(20.0[9.5, 35.0], 13.0[6.5, 22.0]), and the percent time below pH 5.5 (1.36%[0.60%, 4.57%], 1.36%[0.43%, 2.77%]) in the experimental group at the 2nd and 4th week were significantly different from those in the control group (0[0,3.0], 1.0[0.5, 3.8]; 0[0, 0.01%], 0[0, 0], respectively, all P<0.01), suggesting that the experimental group New Zealand rabbits developed LPRD. Compared with the control group under microscope, lymphocytes infiltration and submucosal gland hyperplasia increased in the mucosa of the throat of the experimental group. The results of pepsin immunohistochemical staining between the two groups were statistically significant (P=0.014). Conclusion: The use of balloon dilatation of the LES combined with metal stent dilatation of the UES can successfully establish a laryngopharyngeal reflux model, and lesions in the throat tissue can be observed.
目的： 利用食管内支架联合食管球囊扩张的方法建立新西兰兔咽喉反流动物模型，并探讨模型动物咽喉部组织的病理变化。 方法： 20只新西兰兔随机数字表法分为实验组和对照组，每组10只。实验组采用以球囊扩张食管下括约肌同时联合金属支架扩张食管上括约肌的方法制作咽喉反流动物模型，对照组采用同样的方法置入食管球囊扩张导丝和食管支架置入导丝，但不进行球囊扩张及支架置入。定期观察新西兰兔一般状况、下咽部pH值变化、声带组织病理学改变及胃蛋白酶含量变化，比较实验组与对照组间差异。 结果： Dx-pH监测结果显示术后第2周和第4周实验组pH<5.5咽喉反流的次数均明显高于对照组（20.0[9.5,35.0]次比0[0,3.0]次，13.0[6.5,22.0]次比1.0[0.5,3.8]次），反流总时间百分比亦均明显高于对照组（1.36%[0.60%,4.57%]比0[0,0.01%]，1.36%[0.43%,2.77%]比0[0,0]），差异均有统计学意义（P值均<0.01）。光镜下观察喉部组织标本，与对照组相比，实验组新西兰兔声带标本可见淋巴细胞浸润较多，黏膜下腺体增生。对两组间胃蛋白酶免疫组化染色阳性率进行统计，差异有统计学意义（P=0.014）。 结论： 运用球囊扩张食管下括约肌同时联合金属支架扩张食管上括约肌的方法可成功建立新西兰兔咽喉反流动物模型，咽喉反流可造成咽喉部组织的病变。.
Keywords: Laryngopharyngeal reflux; Models, animal; Pepsin; pH monitoring.