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CASE REPORT |
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Year : 2014 | Volume
: 1
| Issue : 2 | Page : 24-26 |
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Variation of branch of glossopharyngeal nerve leading to the submandibular gland
Ozan Turamanlar1, Ercan Akbay2, Yucel Gonul1, Alaettin Celik1, Ahmet Songur1
1 Department of Anatomy, Faculty of Medicine, Afyon Kocatepe University, Afyonkarahisar, Turkey 2 Department of Otolaryngology, School of Medicine, Mustafa Kemal University, Hatay, Turkey
Date of Web Publication | 22-May-2014 |
Correspondence Address: Ozan Turamanlar Department of Anatomy, Faculty of Medicine, Afyon Kocatepe University, Afyonkarahisar Turkey
Source of Support: None, Conflict of Interest: None | Check |
DOI: 10.4103/2148-7731.132966
Submandibular gland is the second largest salivary gland and comprised of two parts, superficial and deep part. The medial side of the superficial part of the gland neighbors to several structures like glossophayngeal nerve. It is innervated by lingual nerve (sensorial fibers) tympanic chord (parasympathetic fibers) and sympathetic trunk. During a routine dissection, a variant branch of glossopharyngeal nerve entering submandibular gland was observed in an adult male cadaver. During that surgical procedure in the parapharyngeal and submandibular spaces, preservation of the gland function and innervation has a major physiological importance. We did not have any chance to observe the clinical effect of this variation since it was demonstrated on a cadaver. To the best of our knowledge, there is no study published regarding this variation. To bear in mind that submandibular gland can be innervated from glossopharyngeal nerve as a variation is important to preserve the glandular function and to prevent cutting this nerve accidentally during surgery. Keywords: Glossopharyngeal nerve, submandibular gland, variation
How to cite this article: Turamanlar O, Akbay E, Gonul Y, Celik A, Songur A. Variation of branch of glossopharyngeal nerve leading to the submandibular gland. Sifa Med J 2014;1:24-6 |
How to cite this URL: Turamanlar O, Akbay E, Gonul Y, Celik A, Songur A. Variation of branch of glossopharyngeal nerve leading to the submandibular gland. Sifa Med J [serial online] 2014 [cited 2024 Mar 29];1:24-6. Available from: https://www.imjsu.org/text.asp?2014/1/2/24/132966 |
Introduction | | |
Submandibular gland is the second largest salivary gland and it weighs approximately 7-16 g. This gland is located in the submandibular triangle, which is framed with inferior border of the mandible on the upper part and with anterior and posterior venter of digastric muscle on the lower part. Superior part of the gland is covered with platysma muscle and fascia of the neck. In addition, nodi lymphatici submandibulares, facial artery and vein, mylohyoid muscle, linguinal nerve, hypoglossal nerve are located in this triangle. Submandibular gland is located posterolateral to mylohyoid muscle in the most cases. [1] Submandibular gland comprised of two parts, superficial and deep part. The medial side of the superficial part of the gland neighbors to several structures such as glossopharyngeal nerve. [2]
Submandibular gland differentiates from embryologic oral ectoderm in the 6 th weeks of intrauterine life. [1] This gland is very sensitive to the metabolic/physiologic changes. [3] It is innervated by linguinal nerve (sensorial fibers) tympanic chord (parasympathetic fibers) and sympathetic trunk. Parasympathetic fibers reach lingual nerve via tympanic chord and following a synapse at the submandibular ganglion. Then, these fibers reach to the gland. In contrast, sympathetic fibers synapse at superior cervical ganglion and cruise at a close proximity to the vessels (external carotid artery and facial artery) before reaching submandibular gland. [2]
Glossopharyngeal nerve is a mixt nerve consisting of somatomotor, parasympathetic and sensitive fibers. Somatomotor part innervates stylopharyngeus muscle. Parasympathic part induces secretion in the parotid gland, posterior part of tongue and the glands that are adjacent to the mucosa of the pharynx. Sensitive part collects taste sense from the one-third of the posterior tongue and general sense of oropharynx, palatine tonsil, throat, and one-third of the posterior tongue. [4]
Case Report | | |
The aim of this case report is discuss to an innervation variant between submandibular gland and glossopharyngeal nerve. During a routine dissection, a branch of glossopharyngeal nerve entering submandibular gland was observed in an adult male cadaver. As a variation, glossopharyngeal nerve was giving a branch into the superficial lobe of the right submandibular gland [Figure 1] and [Figure 2]. On the other hand, the location and anatomical structure of lingual nerve were noted as normal. | Figure 1: The relationship between right submandibular gland and glossopharyngeal nerve. (a) glossopharyngeal nerve, (b) the branch of glossopharyngeal nerve leading to the superfi cial lobe of submandibular gland, (c) superficial lobe of submandibular gland. Note: The description of superficial lobe of submandibular gland used for small lobe of gland which is located on the mylohyoid muscle
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| Figure 2: Right lingual nerve, the relationship between glossopharyngeal nerve and submandibular gland (a) glossopharyngeal nerve, (b) the cut short portion of branch leading to the submandibular gland which separated from the glossopharyngeal nerve, (c) lingual nerve, (d) superficial lobe of submandibular gland
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Discussion | | |
Close neighborhood of the inner superficial part of submandibular gland and glossopharyngeal nerve can provide a basis for the coexistence of these two different tissues as an unusual variation. Even though, submandibular gland more sensitive to the physiological changes than nerve innervation, we still cannot conclude that this variation does not change the function of the gland. We do not have any chance to observe the clinical effect of this variation since it was demonstrated on a cadaver. To the best of our knowledge, there is no study published regarding this variation. This branch may be originated from the parasympathetic fibers of glossopharyngeal nerve entering into the parotid gland. If the anastomosis between glossopharyngeal nerve, facial and vagal nerve was especially considered, there may be a relationship between our variation and these anastomosis. [5]
Surgery in the floor of the mouth is performed for submandibular gland excision or non-glandular masses and for the congenital anomalies. During the surgical procedure, preservation of the glandular duct and nerve innervation have major physiological importance. Furthermore, due to the growing interest of functional outcomes of head and neck surgery is especially related to the swallowing and residual pain. Surgeons should be aware of on the anatomy of the extracranial course of the glossopharyngeal nerve. [6] To bear in mind that submandibular gland can be innervated from glossopharyngeal nerve as a variation. Hence, it is important to avoid than accidentally cutting this nerve during surgery.
Result | | |
We believe that this anatomical study will convey to surgeons a greater understanding of this complex anatomy. It provides them with indicators to identify the anatomic structures and to guide them when accessing the submandibular gland and lower cranial nerves, in particular, the glossopharyngeal nerve in the parapharyngeal and submandibular spaces with transoral and transervical approaches.
References | | |
1. | Myers EN, Ferris EL. Anatomy, function, and evaluation of the glands. In: Holsinger FC, Bui DT, editors. Salivary Gland Disorders. Berlin Heidelberg: Springer; 2007. p. 1-17. |
2. | Sancak B, Cumhur M. Fonksiyonel Anatomi. 2 nd ed. Ankara: Metu Press; 2002. |
3. | Whelton H. Introduction: the anatomy and physiology of salivary glands. In: Edgar M, Dawes C, O'Mullane D, editors. Saliva and Oral Health. 3 rd ed. London: British Dental Association; 2004. p. 1-3. |
4. | Arýncý A, Elhan A. Anatomi. 3rd ed. Ankara: Güneº Kitabevi; 2001. |
5. | Ozveren MF, Türe U. The microsurgical anatomy of the glossopharyngeal nerve with respect to the jugular foramen lesions. Neurosurg Focus 2004;17:E3. |
6. | Prades JM, Gavid M, Asanau A, Timoshenko AP, Richard C, Martin CH. Surgical anatomy of the styloid muscles and the extracranial glossopharyngeal nerve. Surg Radiol Anat 2014;36:141-6. |
[Figure 1], [Figure 2]
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