Kim H J, Chole R A
Department of Otolaryngology, School of Medicine, University of California, Davis 95616-8647, USA.
Ann Otol Rhinol Laryngol. 1998 Feb;107(2):129-34. doi: 10.1177/000348949810700208.
Mongolian gerbils have a remarkable propensity for the development of aural cholesteatoma; canal cholesteatomas develop spontaneously in aged animals. In the present study, cholesteatomas were produced in a single species, Meriones unguiculatus, by three different methods of induction: 1) external canal ligation (ECL), 2) eustachian tube obstruction (ETO) by electrocautery, and 3) application of propylene glycol (PG) into the middle ear. Each method of induction resulted in cholesteatomas with characteristic features and success rates. With ECL, cholesteatomas could be induced in all ligated ears; stage III and IV cholesteatomas were seen in 4 of 12 ears after 8 weeks. With ETO, cholesteatomas were seen in 7 of 9 animals 8 weeks after induction. With PG, cholesteatomas developed in 2 of 7 animals 4 weeks after induction, although keratin accumulation in the external auditory canal could be found in all animals injected. Although epithelial hyperplasia of the external auditory canal was most prominent in the ECL group, it was also seen in the ETO and PG groups. Keratin accumulation in the ECL or PG group was much greater than that in the ETO group. Thickening of the tympanic membrane, which was most prominent in the PG group, was quite variable in the other groups. Adhesions of the tympanic membrane began at the prominence of the cochlea in the ECL group. In contrast, adhesions in the PG group usually began at the superior bulla, the area in which PG was applied. Each of the three methods of inducing cholesteatoma may be helpful in investigating different clinical aspects of this disease.
蒙古沙鼠极易患上耳胆脂瘤；老年动物会自发形成外耳道胆脂瘤。在本研究中，通过三种不同的诱导方法在单一物种长爪沙鼠（Meriones unguiculatus）中产生胆脂瘤：1）外耳道结扎（ECL），2）通过电灼法阻塞咽鼓管（ETO），以及3）将丙二醇（PG）注入中耳。每种诱导方法都产生了具有特征性表现和成功率的胆脂瘤。采用ECL法，所有结扎耳朵均可诱导出胆脂瘤；8周后，12只耳朵中有4只出现了III期和IV期胆脂瘤。采用ETO法，诱导8周后，9只动物中有7只出现了胆脂瘤。采用PG法，诱导4周后，7只动物中有2只出现了胆脂瘤，不过在所有注射动物的外耳道中均发现有角蛋白积聚。尽管外耳道上皮增生在ECL组最为明显，但在ETO组和PG组中也可见到。ECL组或PG组中的角蛋白积聚远多于ETO组。鼓膜增厚在PG组最为明显，在其他组中则变化较大。ECL组中，鼓膜粘连始于耳蜗突出处。相比之下，PG组中的粘连通常始于上鼓室，即应用PG的区域。这三种诱导胆脂瘤的方法中的每一种都可能有助于研究该疾病的不同临床方面。
