Template:Tube

 Structure [ edit] <img alt="" src="https://upload.wikimedia.org/wikipedia/commons/thumb/2/2e/Blausen_0872_UpperRespiratorySystem.png/220px-Blausen_0872_UpperRespiratorySystem.png" width="220" height="194" class="thumbimage" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/2e/Blausen_0872_UpperRespiratorySystem.png/330px-Blausen_0872_UpperRespiratorySystem.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/2e/Blausen_0872_UpperRespiratorySystem.png/440px-Blausen_0872_UpperRespiratorySystem.png 2x" data-file-width="2500" data-file-height="2200" style="border: 1px solid rgb(204, 204, 204); vertical-align: middle; background-color: rgb(255, 255, 255);">  Upper respiratory system, showingentrance to auditory tube near middle. The Eustachian tube extends from the anterior wall of the middle ear to the lateral wall of the nasopharynx, approximately at the level of the inferior nasal concha</a>. It consists of a bony part and a cartilaginous</a> part. <p style="margin: 0.5em 0px; line-height: 22.4px; color: rgb(37, 37, 37); font-family: sans-serif; font-size: 14px; widows: 1; background-color: rgb(255, 255, 255);">A portion of the tube (1/3) proximal to the middle ear is made of bone; this bony part is about 12 mm in length. It begins in the carotid wall of the tympanic cavity</a>, below the septum canalis musculotubarii, and, gradually narrowing, ends at the angle of junction of the squama</a> and the petrous portion</a> of the temporal bone</a>, its extremity presenting a jagged margin which serves for the attachment of the cartilaginous portion</a> of the rest of the tube,<sup id="cite_ref-3" class="reference" style="line-height: 1; unicode-bidi: -webkit-isolate; font-size: 11.2px;">[3]</a> and this raises a tubal elevation, the torus tubarius</a>, in the nasopharynx where it opens. <p style="margin: 0.5em 0px; line-height: 22.4px; color: rgb(37, 37, 37); font-family: sans-serif; font-size: 14px; widows: 1; background-color: rgb(255, 255, 255);">There are four muscles associated with the function of the Eustachian tube: <ul style="margin: 0.3em 0px 0px 1.6em; padding: 0px; list-style-image: url(data:image/svg+xml,%3C%3Fxml%20version%3D%221.0%22%20encoding%3D%22UTF-8%22%3F%3E%0A%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20version%3D%221.1%22%20width%3D%225%22%20height%3D%2213%22%3E%0A%3Ccircle%20cx%3D%222.5%22%20cy%3D%229.5%22%20r%3D%222.5%22%20fill%3D%22%2300528c%22%2F%3E%0A%3C%2Fsvg%3E%0A); color: rgb(37, 37, 37); font-family: sans-serif; font-size: 14px; line-height: 22.4px; widows: 1; background-color: rgb(255, 255, 255);"><li style="margin-bottom: 0.1em;">Levator veli palatini</a> (innervated by the vagus nerve</a>)</li><li style="margin-bottom: 0.1em;">Salpingopharyngeus</a> (innervated by the vagus nerve)</li><li style="margin-bottom: 0.1em;">Tensor tympani</a> (innervated by the mandibular nerve</a> of CN V</a>)</li><li style="margin-bottom: 0.1em;">Tensor veli palatini</a> (innervated by the mandibular nerve of CN V)</li></ul>