Withnell R H
Auditory Physiology Laboratory, Northwestern University, Evanston, Illinois, USA.
Ear Hear. 2001 Feb;22(1):75-7. doi: 10.1097/00003446-200102000-00008.
The extra-cellular cochlear microphonic is believed to be generated predominantly by outer hair cells and therefore it would seem reasonable to assume that the presence of a cochlear microphonic excludes outer hair cell dysfunction. Indeed, a diagnosis of auditory neuropathy might be, and has been, made on the basis of a cochlear microphonic present with an abnormal auditory brainstem response. Animal studies, however, have shown that the cochlear microphonic recorded from the round window is dominated by cellular generators located in the base of the cochlea. Primarily on this basis, it is argued that the presence of a cochlear microphonic does not exclude outer hair cell pathology and so outer hair cell integrity should not necessarily be inferred from the presence of the cochlear microphonic alone. In contrast, the absence of an otoacoustic emission in such cases is consistent with outer hair cell dysfunction.
细胞外耳蜗微音电位被认为主要由外毛细胞产生，因此可以合理推测，存在耳蜗微音电位可排除外毛细胞功能障碍。实际上，听觉神经病的诊断可能且已经基于存在耳蜗微音电位但听觉脑干反应异常而做出。然而，动物研究表明，从圆窗记录到的耳蜗微音电位主要由位于耳蜗底部的细胞发生器主导。主要基于此，有人认为存在耳蜗微音电位并不能排除外毛细胞病变，因此不能仅从存在耳蜗微音电位就必然推断出外毛细胞的完整性。相比之下，在这种情况下没有耳声发射则与外毛细胞功能障碍一致。
