鼓膜(膜鼓膜)是一個11×9毫米的薄半透明橢圓形板,將外耳道與鼓腔(中耳)分開。鼓膜固定在耳道的末端,在顳骨的鼓部分的凹槽中。該膜的低得多的部為拉伸部分(平坦部tensa),和上,約2毫米寬,鄰接顳骨鱗狀部分,稱為鬆弛部分(鬆弛部)。相對於外耳道的軸線,鼓膜傾斜地定位並且其下壁與外部形成45-55°的打開角度。在膜的中心有一個加深的 - umbo mebranae tympani,對應於從其內側連接錘柄的端部。鼓膜由纖維組織構成,其周圍區域的纖維主要是徑向取向的,中心是圓形的。外部鼓膜覆蓋有形成的表皮層(皮狀層),並從鼓膜表皮 - 粘膜 - 粘膜層(層mucosum)。在鼓膜未拉伸的部分沒有纖維層,皮膚層直接屬於粘膜層。
Translation Disclaimer: For the convenience of users of the iLive portal this article has been translated into the current language, but has not yet been verified by a native speaker who has the necessary qualifications for this. In this regard, we warn you that the translation of this article may be incorrect, may contain lexical, syntactic and grammatical errors. |