Kartum Tufan Agah, Kucukyuruk Baris, Kaya Alperen, Aydin Levent, Tanrıöver Necmettin, Sanus Galip Zihni
Neurosurgery Clinic, Midyat State Hospital, Mardin, Türkiye.
Microsurgical Neuroanatomy Laboratory, Cerrahpaşa Faculty of Medicine, Istanbul University-Cerrahpasa, Istanbul, Türkiye.
J Neurol Surg B Skull Base. 2024 Feb 9;86(1):27-33. doi: 10.1055/a-2235-9956. eCollection 2025 Feb.
The absence of precise landmarks in the middle fossa floor and frequent anatomical variations make it difficult to localize the internal acoustic canal (IAC) during the middle fossa approach (MFA). We aimed to investigate the reliability and utility of the neuronavigation system (NNS) in the MFA and to delineate specific technical considerations regarding NNS during the approach. One-millimeter-thin section computed tomography scans were performed on five formalin-fixed human cadavers (10 sides). During the MFA, structures, such as the IAC, vestibule and cochlea hidden in the temporal bone were investigated under NNS guidance. All the superficial landmarks, such as the foramen spinosum and ovale were correctly localized by NNS. Deeper landmarks, such as the central part of the IAC lying beneath the surface of the petrous apex could not be localized via NNS. The exact area of bone removal along roof of IAC was determined by using the orientation provided by the probe placed between the basal turn of cochlea and the vestibule. We were able to validate the location of the IAC via a medial to lateral drilling by using the navigation this reference point. The NNS can be used effectively during the MFA, and localizing superficial landmarks on the middle fossa floor with a higher accuracy may prove helpful in identifying the IAC from above. By referring to the cochlea-vestibule junctional area, the exact location of the trace of the IAC can be revealed.
中颅窝底缺乏精确的解剖标志且解剖变异频繁，使得在中颅窝入路（MFA）过程中难以定位内耳道（IAC）。我们旨在研究神经导航系统（NNS）在MFA中的可靠性和实用性，并阐述该入路过程中关于NNS的具体技术要点。对5具经福尔马林固定的人体尸体（10侧）进行了1毫米薄层计算机断层扫描。在MFA过程中，在NNS引导下对颞骨内隐藏的结构，如IAC、前庭和耳蜗进行了研究。所有浅表标志，如棘孔和卵圆孔，均通过NNS准确定位。位于岩尖表面下方的IAC中央部分等更深层的标志无法通过NNS定位。通过使用置于耳蜗底转和前庭之间的探针所提供的方向，确定了沿IAC顶部的精确骨质去除区域。利用该参考点进行导航，我们能够通过从内侧到外侧的钻孔来验证IAC的位置。NNS在MFA过程中可以有效使用，以更高的精度定位中颅窝底的浅表标志可能有助于从上方识别IAC。通过参考耳蜗 - 前庭交界区域，可以揭示IAC轨迹的准确位置。
