1Division of Neurological Surgery and.
2Department of Neuropathology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona.
J Neurosurg. 2020 Jan 1;132(1):277-283. doi: 10.3171/2018.6.JNS18856. Epub 2019 Jan 4.
In the current neurosurgical and anatomical literature, the intracanalicular segment of the ophthalmic artery (OphA) is usually described to be within the optic nerve dural sheath (ONDS), implying direct contact between the nerve and the artery inside the optic canal. In the present study, the authors sought to clarify the exact relationship between the OphA and ONDS.
Ten cadaveric heads were subjected to endoscopic endonasal and transcranial exposures of the OphA in the optic canal (5 for each approach). The relationship between the OphA and ONDS was assessed. Histological examination of one specimen of the optic nerve and the accompanying OphA was also performed to confirm the relationship with the ONDS.
In all specimens, the OphA coursed between the two layers of the dura (endosteal and meningeal) and was not in direct contact with the optic nerve, except for the first few millimeters of the proximal optic canal before it pierced the ONDS. Upon reaching the orbit, the two layers of the dura separated and allowed the OphA to literally float within the orbital fat. The meningeal dura continued as the ONDS, whereas the endosteal dura became the periorbita.
This study clarifies the interdural course of the OphA within the optic canal. This anatomical nuance has important neurosurgical implications regarding safe exposure and manipulation of the OphA.
在当前的神经外科和解剖学文献中，眼动脉（OphA）的管内段通常被描述为视神经硬脑膜鞘（ONDS）内，这意味着在视神经管内神经和动脉之间存在直接接触。在本研究中，作者试图阐明 OphA 与 ONDS 的确切关系。
10 具尸体头颅接受了经鼻内镜和颅内外暴露视神经管内 OphA 的手术（每种方法 5 具）。评估了 OphA 与 ONDS 之间的关系。还对视神经和伴随的 OphA 的一个标本进行了组织学检查，以确认与 ONDS 的关系。
在所有标本中，OphA 位于硬脑膜的两层（内骨膜和脑膜）之间，除了在它穿透 ONDS 之前的视神经管的前几毫米处，与视神经没有直接接触。到达眼眶后，硬脑膜的两层分开，使 OphA 实际上可以在眶脂肪内漂浮。脑膜硬脑膜继续作为 ONDS，而内骨膜硬脑膜成为眶骨膜。
本研究阐明了 OphA 在视神经管内的硬脑膜间走行。这一解剖学细微差别对 OphA 的安全暴露和操作具有重要的神经外科意义。
