Schmidt S H, Hellström S, Carlsöö B
Arch Otorhinolaryngol. 1984;240(2):159-66. doi: 10.1007/BF00453474.
Four different local anaesthetic agents were tested on the tympanic membrane of the rat in order to detect any structural changes. Specimens were obtained for examination under the light microscope 10 min, 24 h, 1 week, and 2 weeks after exposure to each anaesthetic. The histological changes observed were, in general, rather similar for all agents tested, although certain differences were noted. The initial change observed was damage of the outer epithelial layers, later also accompanied by changes in the corresponding endothelial cover. No perforations were observed macroscopically. The healing process was characterized by hyperplasia of the connective tissue layers of the drum. However, the most prominent feature of this process was the hyperplastic epithelium, ingrowing from the periphery of the membrane to cover denuded areas. During certain stages of the healing process the thickness of the membrane amounted to 40 times that of the normal drum. The initial changes appeared severe both with the clinically more potent and effective anaesthetics (phenol and Bonain's liquid), and with Xylocaine spray.
为检测任何结构变化，在大鼠鼓膜上测试了四种不同的局部麻醉剂。在暴露于每种麻醉剂后10分钟、24小时、1周和2周获取标本，用于光学显微镜检查。尽管注意到了某些差异，但总体而言，所有测试药剂观察到的组织学变化相当相似。观察到的初始变化是外层上皮层受损，随后相应的内皮覆盖物也发生变化。肉眼未观察到穿孔。愈合过程的特征是鼓膜结缔组织层增生。然而，该过程最显著的特征是增生的上皮细胞从膜的周边向内生长以覆盖裸露区域。在愈合过程的某些阶段，鼓膜厚度达到正常鼓膜的40倍。使用临床上效力更强、效果更好的麻醉剂（苯酚和博纳因液）以及利多卡因喷雾剂时，初始变化似乎都很严重。
