Letter to the editor: The course of lingual artery from transoral robotic view.

To the Editor: Goyal et al recently published an anatomic study about the surgical anatomy of the supraglottic larynx using the da Vinci robot. In this publication, the course of lingual artery has been described as lateral to hyoglossus muscle, which separates the artery from the lingual nerve. The authors exposed the lingual artery while describing the endoscopic anatomy of the supraglottic larynx. However, the lingual artery has been shown lateral to the digastric muscle in their Figures 3, 4, 5, and 6. The above findings were not confirmed with lateral neck (transcervical) exploration either. This article challenges previous anatomic studies, to the best of our knowledge, lingual artery arises from the external carotid artery as a second anterior branch; it first runs obliquely upward and medialward to the greater cornu of the hyoid bone; it then curves downward and forward, forming a loop that is crossed by the hypoglossal nerve, and passes medial to the digastric and stylohyoid muscles (Figure 1), and lateral to styloglossus muscle (Figure 2). Then, it runs lateral to the hyoglossus muscle and enters to the base of tongue. Because the lingual artery courses beneath the digastric and stylohyoid muscles and superior to greater horn of hyoid bone (Figures 1 and 2), neck dissection performed over these muscles prevents lingual artery injury in daily practice. Similarly, dissecting medial to the styloglossus muscle may prevent lingual artery injury during transoral robotic base of tongue interventions (Figure 1C). We have used 2 fresh cadavers to confirm the relationship between the course of the styloglossus muscle and lingual artery. All cadavers were dissected via transoral route and then the transorally described structures were confirmed by lateral neck exploration. Our dissections revealed that the muscle that was described as the digastric muscle by Goyal et al should be the styloglossus muscle. This misinterpretation of the styloglossus muscle may cause confusion during transoral robotic surgery and consequent vascular complications.