Section of Otolaryngology, Department of Surgical Sciences, Head and Neck Surgery.
Section of Orthopedics, Department of Surgical Sciences, Uppsala University Hospital, Uppsala, Sweden.
Otol Neurotol. 2018 Jul;39(6):e429-e435. doi: 10.1097/MAO.0000000000001831.
We sought to study the anatomic variations of the cochlear aqueduct and its accessory canals in human temporal bones using micro-CT and a 3D reconstruction paradigm. More knowledge about the anatomic variations of these structures, particularly at the basal turn of the cochlea and round window niche, may be important to better preserve residual hearing as well as the neural supply during cochlear implant surgery.
An archival collection of 30 human temporal bones underwent micro-CT and 3D reconstruction. A surface enhancement paradigm was applied. The application displays reconstructed slices as a 3D object with realistic 3D visualization of scanned objects. Virtual sectioning or "cropping" of the petrous bone presented subsequent areas. Thereby, the bony canals could be followed from inside the basal turn of cochlea and middle ear to the jugular foramen.
The cochlear aqueduct was always paralleled by an accessory canal containing the inferior cochlear vein. It ran from the basal turn of the cochlea and exited laterally in the jugular foramen. In 70% of the cases, a secondary accessory canal was observed and it derived mostly from a depression or infundibulum located in the floor of the round window niche. This canal also exited in the jugular foramen. The secondary accessory canal occasionally anastomosed with the primary accessory canal suggesting that it contains a vein that drains middle ear blood to the cranial sinus.
Micro-CT with 3D surface reconstruction paradigm offers new possibilities to study the topographic anatomy of minor details in the human inner ear. The technique creates simulated transparent "castings" of the labyrinth with a coinciding surface view through enhancement of contrast between boundaries. Accessory canals that drain blood from the cochlea, spiral ganglion, and middle ear could be characterized three-dimensionally.
我们旨在通过微 CT 和 3D 重建范式研究人类颞骨耳蜗导水管及其附属管道的解剖变异。更好地了解这些结构的解剖变异，尤其是在耳蜗基底回和圆窗龛处，对于更好地保留残余听力以及在耳蜗植入手术中保护神经供应可能非常重要。
对 30 个人类颞骨进行了微 CT 和 3D 重建的档案收集。应用了表面增强范例。该应用程序将重建的切片显示为 3D 对象，对扫描对象进行了逼真的 3D 可视化。对岩骨的虚拟切片或“裁剪”呈现了后续区域。由此，可以从耳蜗基底回和中耳内部追踪到骨管，直至颈静脉孔。
耳蜗导水管始终与包含下耳蜗静脉的附属管道平行。它从耳蜗基底回开始，在颈静脉孔处向外侧退出。在 70%的情况下，观察到一个次要的附属管道，它主要源自位于圆窗龛底部的凹陷或漏斗。这条管道也在颈静脉孔处退出。次要附属管道偶尔与主要附属管道吻合，表明它包含一条将中耳血液引流至颅窦的静脉。
微 CT 与 3D 表面重建范例相结合，为研究人类内耳小细节的拓扑解剖提供了新的可能性。该技术通过增强边界之间的对比度，创建了迷路的模拟透明“铸件”，并具有相应的表面视图。可以对从耳蜗、螺旋神经节和中耳引流血液的附属管道进行三维特征描述。
