豚鼠半规管阻塞术中听性脑干反应的变化

Changes of ABR Threshold During Semicircular Canal Occlusion in Guinea Pigs

目的 观察正常豚鼠行三个半规管阻塞术中ABR反应阈值的动态变化。方法 健康白色纯种豚鼠10只 ,分别于术前、打开听泡、开放与阻塞各个半规管后测ABR阈值。结果 三个半规管阻塞结束后 ,ABR阈值平均升高 6 .82dB。各个半规管开窗前后ABR阈值上升较明显 ,而阻塞前后ABR阈值变化不明显。结论 半规管阻塞术中的听力下降是一个渐进的过程 ,引起听力下降的主要原因可能是外淋巴的流失 。

Objective To observe the changes of ABR threshold during semicircular canal occlusion in normal guinea pigs.Methods 10 guinea pigs were tested.The auditory brainstem response(ABR) was recorded before operation,after opening the otocyst,drilling and blocking each canal.Results The ABR threshold increased 6.82 dB after finishing all the procedure,similar to the conclusion in our previous observation.ABR threshold increased significantly after drilling of the canal,while it did not increase significantly after blocking the canal.Conclusion The changes of ABR threshold showed a step-by-step process, mainly due to the loss of perilymph.Stimulation of the labyrinth did not have much contribution to the increase of ABR threshold.