Department of Normal and Clinical Anatomy, Interfaculty Chair of Anatomy and Histology, Medical University of Lodz, Łódź, Poland.
Department of Neurosurgery, Seattle Science Foundation, Seattle, Washington.
Clin Anat. 2020 May;33(4):585-591. doi: 10.1002/ca.23452. Epub 2019 Aug 20.
The latest research suggests that the abducens nerve may be divided into subbranches that reach functionally distinct zones of the lateral rectus muscle. The goal of the study was to examine this muscle's innervation, including the detailed distribution of the intramuscular subbranches of the abducens nerve. Twenty-five lateral rectus muscle specimens were harvested (with the orbital segment of the abducens nerve), fixed in 10% formalin solution, and stained with Sihler's whole mount nerve staining technique. Subbranches running to the lateral rectus divided into two main groups: superior and inferior. Both groups of subbranches are distributed in a fan-shaped manner, show a characteristic "tree-like" branching pattern and form terminal plexus near the proximal half of the lateral rectus muscle. However, some smaller subbranches run as far as the muscle's insertion, and recurrent subbranches also reach its origin. With respect to their course to the muscle's origin or insertion, the smallest subbranches running within the muscle may be associated with innervation of the tendon. In the majority of cases (88%), superior and inferior subbranches of the abducens nerve overlapped in the central one-third of the lateral rectus muscle's width so that any clearly distinct anatomical segments of the muscle could be observed based on Sihler's technique. In the remaining 12% of specimens, superior and inferior groups of subbranches innervated two distinct compartments of the lateral rectus muscle with no overlapping. Dense, fan-shaped distribution of abducens nerve intramuscular subbranches can be observed within the lateral rectus muscle. Clin. Anat. 33:585-591, 2020. © 2019 Wiley Periodicals, Inc.
最新研究表明，外展神经可能分为亚支，这些亚支到达外直肌的功能不同的区域。本研究的目的是检查该肌肉的神经支配，包括外展神经肌内亚支的详细分布。采集 25 个外直肌标本（带有外展神经眶段），用 10%甲醛溶液固定，用 Sihler 全脊神经染色技术染色。支配外直肌的分支分为两组：上支和下支。两组分支呈扇形分布，呈特征性的“树状”分支模式，并在外直肌近段形成终末丛。然而，一些较小的分支可延伸至肌肉的止点，还有一些返支也可达其起点。就其到达肌肉起点或止点的行程而言，在肌肉内走行的最小分支可能与肌腱的神经支配有关。在大多数情况下（88%），外展神经的上、下支在外直肌宽度的中央三分之一处重叠，因此可以根据 Sihler 技术观察到肌内有明显的解剖节段。在其余 12%的标本中，上、下两组分支支配外直肌的两个不同区域，没有重叠。在外直肌内可以观察到外展神经肌内分支密集的扇形分布。临床解剖学 33:585-591,2020. © 2019 Wiley Periodicals, Inc.
