ANATOMICAL AND SURGICAL LANDMARKS OF THE STYLOGLOSSUS MUSCLE IDENTIFIED THROUGH TRANSORAL ENDOSCOPIC DISSECTION OF THE PARAPHARYNGEAL SPACE
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Abstract
Background: Transoral endoscopic approaches to the parapharyngeal space (PPS) are increasingly used to avoid morbidity of external routes, yet they remain challenging because of the narrow working corridor and the “inside‑out” anatomical view.
Objectives: To describe endoscopic identification of the styloglossus muscle (SGM), evaluate its relationship with high‑risk neurovascular structures, and propose an SGM‑based stepwise orientation for PPS surgery.
Methods: A descriptive cadaveric dissection study was performed on 10 fresh adult cadaveric heads (20 sides). Transoral endoscopic dissections were carried out to expose the prestyloid PPS, identify the SGM, and measure distances from the SGM to the lateral pharyngeal mucosa, the lingual nerve at two levels, and the external carotid artery (mm).
Results: The SGM was identified in all specimens as an oblique muscular bundle running from the styloid region to the tongue base. It appeared early after removal of prestyloid fat and consistently overlaid the external carotid artery and its branches posteriorly. The lingual nerve coursed superolateral to the SGM and approached it toward the tongue base.
Conclusions: The SGM is a reliable soft‑tissue landmark for transoral endoscopic access to the PPS and may serve as the posterior safe limit of the prestyloid compartment before entering the vascular‑rich poststyloid region.
Keywords
styloglossus, parapharyngeal space, transoral endoscopy, anatomical landmark, cadaveric dissection
Article Details
References
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