Wang Minghao, Chae Ricky, Vigo Vera, Winkler Ethan, McDermott Michael W, El-Sayed Ivan H, Abla Adib A, Rubio Roberto Rodriguez
Department of Neurosurgery, First Affiliated Hospital of China Medical University, Shenyang, China; Skull Base and Cerebrovascular Laboratory, University of California, San Francisco, San Francisco, California, USA.
Skull Base and Cerebrovascular Laboratory, University of California, San Francisco, San Francisco, California, USA; Department of Neurological Surgery, University of California, San Francisco, San Francisco, California, USA.
World Neurosurg. 2019 Jul;127:e1083-e1096. doi: 10.1016/j.wneu.2019.04.048. Epub 2019 Apr 11.
The lower clivus (LC) is one of the most difficult areas to access in neurosurgery. Several microsurgical approaches to the LC have been reported, including the subtonsillar, far-lateral (FL), extreme-lateral (EL), and endoscopic far-medial (Endo-FM). However, no consensus has been reached regarding the optimal approach. We aimed to quantify and compare the surgical exposure and freedom (angle of attack) for various targets at the LC using these 4 surgical approaches.
The subtonsillar, FL, EL, and Endo-FM approaches were performed on 5 cadaveric specimens (total 10 sides). Surgical exposure and freedom were measured using the neuronavigation system.
At the LC, the Endo-FM approach provided the greatest area of exposure (459.3 ± 82.2 mm). For surgical freedom, the EL approach provided the greatest angle of attack at the jugular foramen (98.1° ± 9.2°) and hypoglossal canal (128.8° ± 26.1°). The Endo-FM was the only approach that provided access to the midline of the LC in all specimens. However, the surgical freedom at the midline (20.9° ± 2.4° at the level of the jugular foramen; 24.2° ± 2.9° at the level of hypoglossal canal) was limited by its deep surgical corridor (104.3 ± 11.2 mm) compared with the EL and FL approaches.
The Endo-FM approach provided the greatest surgical freedom at the ventral aspect but the least freedom at the lateral aspect. The EL approach provided maximal values for most parameters among the open approaches; however, the craniotomy with the EL approach was the most complicated. Our quantitative results could guide neurosurgeons in preoperative planning for LC lesions, including awareness of the maximum exposure limits and the advantages and disadvantages of each surgical approach.
下斜坡是神经外科手术中最难到达的区域之一。已经报道了几种针对下斜坡的显微手术入路，包括扁桃体下、远外侧（FL）、极外侧（EL）和内镜远内侧（Endo-FM）入路。然而，关于最佳入路尚未达成共识。我们旨在使用这4种手术入路量化并比较下斜坡不同靶点的手术显露范围和自由度（攻击角度）。
对5具尸体标本（共10侧）进行扁桃体下、FL、EL和Endo-FM入路手术。使用神经导航系统测量手术显露范围和自由度。
在下斜坡，Endo-FM入路提供了最大的显露面积（459.3±82.2平方毫米）。对于手术自由度，EL入路在颈静脉孔（98.1°±9.2°）和舌下神经管（128.8°±26.1°）处提供了最大的攻击角度。Endo-FM是所有标本中唯一能够到达下斜坡中线的入路。然而，与EL和FL入路相比，由于其手术通道较深（104.3±11.2毫米），中线处的手术自由度有限（颈静脉孔水平为20.9°±2.4°；舌下神经管水平为24.2°±2.9°）。
Endo-FM入路在腹侧提供了最大的手术自由度，但在外侧提供的自由度最小。EL入路在开放入路中大多数参数的值最大；然而，EL入路的开颅手术最为复杂。我们的定量结果可以指导神经外科医生对下斜坡病变进行术前规划，包括了解最大显露范围限制以及每种手术入路的优缺点。
