Comparative analysis of endoscopic endonasal far-medial, far-lateral transcondylar and combined approaches to the foramen magnum region: volumetric analysis and quantitative insights on surgical exposure and maneuverability

IF 1.9 3区医学 Q3 CLINICAL NEUROLOGY

Acta Neurochirurgica Pub Date : 2026-09-28 Epub Date: 2026-10-01 DOI:10.1007/s00701-026-07039-3

Rachel Blue, Yan Zhou, Kamila Bond, Sonia Ajmera, Reinier Alvarez, Ross Moseley, Patrick Hosokawa, A. Samy Youssef

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引用次数: 0

Abstract

Background

Surgical access to the anterior craniovertebral junction (CVJ) and foramen magnum region remains technically challenging due to dense neurovascular anatomy and limited working corridors. Although the far-lateral transcondylar and endoscopic far-medial approaches are both employed clinically, direct quantitative comparisons of maneuverability and volumetric exposure are still lacking.

Objective

To quantitatively assess and compare surgical maneuverability, anatomic limits and volume of exposure of the endoscopic far-medial, far-lateral, and combined approaches.

Methods

Five latex-injected cadaveric heads underwent dissection via an endoscopic endonasal far-medial approach (EEFM), contralateral far-lateral transcondylar approach (FL), and a combined approach. Surgical freedom, horizontal and vertical angles of attack, and volumetric exposure were measured using neuronavigation and 3D CT-based segmentation. Site-specific measurements were obtained at the hypoglossal canal, jugular foramen, and vertebrobasilar junction. Statistical comparisons were made using Wilcoxon rank-sum tests.

Results

The FL demonstrated significantly greater surgical freedom (363 mm² vs. 6.8 mm², P = .01), horizontal angle of attack (99° vs. 8.1°, P = .01), and vertical angle of attack (78° vs. 15.4°, P = .01) compared to the EEFM. The EEFM yielded the smallest mean total volume (5.53 ± 2.01 cm³), primarily concentrated in the anteromedial compartment (4.70 ± 1.67 cm³). The FL offered a significantly larger mean total exposure (15.12 ± 1.93 cm³, p < 0.001), dominated by posterolateral access (12.60 ± 2.16 cm³, p < 0.001). The combined approach provided the greatest overall exposure volume (18.76 ± 3.58 cm³), with substantial access to both the posterolateral (12.90 ± 2.32 cm³) and anteromedial (5.86 ± 1.95 cm³) compartments.

Conclusion

The far-lateral approach offers superior surgical freedom and posterolateral exposure, while the far-medial endoscopic approach provides a direct but limited midline corridor predominantly anteromedial foramen magnum lesions. The combined approach maximizes volumetric access and should be considered for extensive foramen magnum lesions particularly engulfing or anterior to neurovascular structures.

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鼻内窥镜下大孔区远内、远外侧经髁入路和联合入路的比较分析：体积分析和手术暴露和可操作性的定量见解。

背景：由于密集的神经血管解剖结构和有限的工作通道，手术进入前颅椎交界处（CVJ）和枕骨大孔区域在技术上仍然具有挑战性。尽管临床上均采用远外侧经髁入路和内窥镜远内侧入路，但仍然缺乏可操作性和容积暴露的直接定量比较。目的：定量评估和比较内镜下远内侧入路、远外侧入路和联合入路的手术可操作性、解剖限制和暴露量。方法：采用内镜下鼻内远内侧入路（EEFM）、对侧远外侧经髁入路（FL）和联合入路对5例注射乳胶的尸体头部进行解剖。使用神经导航和基于3D ct的分割测量手术自由度、水平和垂直攻角以及体积暴露。在舌下管、颈静脉孔和椎基底动脉连接处进行了特定部位的测量。采用Wilcoxon秩和检验进行统计学比较。结果：FL表现出更大的手术自由度(363 mm2 vs. 6.8 mm2, P =。01)，水平攻角(99°vs. 8.1°，P =。01)，垂直攻角(78°vs. 15.4°，P =。01)与EEFM相比。EEFM平均总容积最小（5.53±2.01 cm3），主要集中在前内侧室（4.70±1.67 cm3）。FL提供了更大的平均总暴露量（15.12±1.93 cm3, p 3, p 3），可大量进入后外侧（12.90±2.32 cm3）和前内侧（5.86±1.95 cm3）隔室。结论：远外侧入路提供了更好的手术自由和后外侧暴露，而远内侧内镜入路提供了一个直接但有限的中线通道，主要是前内侧大孔病变。联合入路可最大限度地扩大手术容量，对于大枕骨大孔病变，特别是吞噬或前部神经血管结构的病变应予以考虑。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Acta Neurochirurgica 医学-临床神经学

CiteScore

4.40

自引率

4.20%

发文量

342

审稿时长

1 months

期刊介绍： The journal "Acta Neurochirurgica" publishes only original papers useful both to research and clinical work. Papers should deal with clinical neurosurgery - diagnosis and diagnostic techniques, operative surgery and results, postoperative treatment - or with research work in neuroscience if the underlying questions or the results are of neurosurgical interest. Reports on congresses are given in brief accounts. As official organ of the European Association of Neurosurgical Societies the journal publishes all announcements of the E.A.N.S. and reports on the activities of its member societies. Only contributions written in English will be accepted.