Where is glossopharyngeal nerve located

Functional parotid gland changes may be unnoticed, as the other salivary glands remain unaffected [ 1 ]. More debatable is the possibility of secondary gland atrophy after denervation. Parotid atrophy has been reported in cases of chronic trigeminal denervation, as the auriculotemporal nerve conveys the gland innervations [ 30 ]. Though we found no previous articles on parotid gland atrophy related to lesions affecting the GPN pathway, tympanic neurectomies were reported to show that atrophy [ 31 ] and the radiologist should consider this possibility Fig.

Glossopharyngeal nerve dysfunction. Low cranial nerves palsy. A slightly hypointense mass eroding the right jugular foramen arrow was demonstrated to be a glomus jugulare paraganglioma. The normal stylopharyngeus muscle arrowhead on the left and its relationship with the external carotid artery eca help to recognise the muscle atrophy on the right side.

Stylopharyngeus muscle atrophy is one of the few specific imaging signs of glossopharyngeal nerve dysfunction. An asymmetric oropharyngeal lumen due to a descending soft palate on the right arrow and constrictor muscle atrophy the arrowhead points to the normal muscles on the left.

These are signs of vagus nerve dysfunction, which is normally associated with glossopharyngeal nerve changes. The uvula arrow is displaced to the left side the dotted midline has been drawn to emphasise that displacement , which is the other typical sign of vagus nerve palsy.

Intriguingly, this patient also showed a right parotid gland pg atrophy, which might be related to the glossopharyngeal nerve dysfunction. Also note the fat replacement of the right side of the tongue due to hypoglossal nerve palsy. The novelty of this article is the specific focus on the glossopharyngeal nerve GPN in cross-sectional imaging, which systematises the anatomical relationships of the main trunk and its branches. Semin Neurol — Butterworths, Boston, pp — Google Scholar.

Neuroimaging Clin N Am — Article PubMed Google Scholar. Diagn Interv Imaging — Gross anatomy, cross-sectional imaging references and pathology.

Testut L Nervios craneales. Salvat, Barcelona, pp 53— Masson, Barcelona, pp — Harcourt, Madrid, pp — Neurosurgery — Eur J Radiol — Simon E, Mertens P Functional anatomy of the glossopharyngeal, vagus, accessory and hypoglossal cranial nerves.

Neurochirurgie — Liang C, Du Y, Xu J et al MR imaging of the cisternal segment of the posterior group of cranial nerves: neurovascular relationships and abnormal changes. Rubinstein D, Burton BS, Walker AL The anatomy of the inferior petrosal sinus, glossopharyngeal nerve, vagus nerve, and accessory nerve in the jugular foramen. Neurosurgery 61 3 Suppl — PubMed Google Scholar. Harnsberger HR The carotid space.

In: Harnsberger HR ed Handbook of head and neck imaging, 2nd edn. Mosby Year Book, St. Louis, pp 75— Kiya N, Sawamura Y, Dureza C, Fukushima T Minimally invasive surgical exposure of the extreme high cervical internal carotid artery: anatomical study. J Clin Neurosci — Borges A Imaging of denervation in the head and neck.

World Neurosurg — Radiology — Magn Reson Med Sci — Histopathologic, histochemical, and clinical study. Arch Otolaryngol — Download references.

The manuscript comes from an electronic poster presented as an educational exhibit during the European Congress of Radiology ECR held in Vienna in March , where it was distinguished with a cum laude award. You can also search for this author in PubMed Google Scholar. Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Reprints and Permissions. Tracking the glossopharyngeal nerve pathway through anatomical references in cross-sectional imaging techniques: a pictorial review. Insights Imaging 9, — Download citation. Received : 04 October Revised : 09 April Accepted : 16 April Published : 13 June Issue Date : August Anyone you share the following link with will be able to read this content:. Sorry, a shareable link is not currently available for this article.

Provided by the Springer Nature SharedIt content-sharing initiative. Skip to main content. Search all SpringerOpen articles Search. Download PDF. Abstract The glossopharyngeal nerve GPN is a rarely considered cranial nerve in imaging interpretation, mainly because clinical signs may remain unnoticed, but also due to its complex anatomy and inconspicuousness in conventional cross-sectional imaging.

Introduction The glossopharyngeal nerve GPN or IX cranial nerve is one of the most unattended cranial nerves in imaging examinations. Functional anatomy and clinical manifestations The GPN conveys: 1 sensory afferents retroauricular region , visceral afferents posterior third of the tongue, pharyngeal tonsil, posterior pharynx, middle ear and Eustachian tube and taste afferents posterior third of the tongue ; 2 parasympathetic afferents carotid sinus baroreceptors and carotid body chemoreceptors and efferents parotid gland ; and 3 motor efferents stylopharyngeus muscle [ 1 , 2 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 ].

Cross-sectional anatomy For the purpose of systematisation, we will follow the pattern of Policeni and Smoker [ 3 ]. Origin in the brain stem The GPN and vagus nerve are mixed nerves that contain motor, branchial, sensory and autonomic fibres [ 16 ].

Full size image. It then curves forward, forming an arch on the side of the neck and lying upon the stylopharyngeus and middle pharyngeal constrictor muscle.

From there it passes under a cover of the hyoglossus muscle, and is finally distributed to the palatine tonsil, the mucous membrane of the fauces and base of the tongue, and the mucous glands of the mouth. In passing through the jugular foramen, the nerve presents two ganglia, the superior and the petrous:.

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Log In. Sign Up. Become a Gold Supporter and see no ads. Log in Sign up. Articles Cases Courses Quiz. About Recent Edits Go ad-free. Edit article. View revision history Report problem with Article. Citation, DOI and article data. Wahba, M. At that point, the glossopharyngeal nerve sends off the carotid sinus nerve, which then runs downward in the neck to the carotid artery.

Next, it runs under the hyoglossus muscle, which comes up the side of the neck and connects to the tongue. It then gives off its three terminal branches:. Many nerves have anatomical variations that doctors, especially surgeons, need to be familiar with so they don't inadvertently injure them during procedures.

Knowing about them can also help diagnose problems with nerve function. In most people, the glossopharyngeal nerve curves around the front of the stylopharyngeus muscle, but in some cases, it penetrates this muscle instead. Some research has shown that a small percentage of people have abnormal connections between the glossopharyngeal and vagus nerves where they travel close together inside the skull. That's especially important during surgery in that area to keep the nerve fibers from being cut.

The glossopharyngeal nerve serves a variety of functions in the head and neck through different types of nerve fibers and its various branches.

The glossopharyngeal nerve plays a sensory role in numerous important structures. In the middle ear, via its tympanic branch, it becomes part of the tympanic plexus. That's a network of nerves that provides sensory function to the middle ear, the eustachian tube, and the internal surface of the tympanic membrane your eardrum.

The carotid sinus nerve, which connects to the carotid artery, provides information to your brain about blood pressure and oxygen saturation. The pharyngeal branch provides sensation to the mucous membranes in the opening to the throat between the soft palate and epiglottis.

The tonsillar branch supplies sensation to the tonsils. The lingual branch performs the specialized task of transmitting taste information to your brain. It connects with the taste buds on the rear third of your tongue and down into the throat, and it also provides that area with general sensory information about things like touch, temperature, and pain.

The chorda tympani nerve , which is a branch of the facial nerve the seventh cranial nerve , innervates the forward two-thirds of the tongue. The lingual branch and chorda tympani provide what's called inhibition to each other's signals, meaning that they dampen the signals that are sent to the brain.

Experts think this might happen in order to allow the brain to tell the difference between a wider variety of tastes. Damage to one of these nerves takes away that inhibiting effect and can lead to an increase in your perception of particular tastes as well as an increase in tongue-related pain. The glossopharyngeal nerve provides motor function to the stylopharyngeus muscle. Located in the pharynx, which is the portion of your throat behind the nose and mouth, this muscle is involved in swallowing.

It shortens and widens the pharynx and lifts the larynx commonly called the voice box when you swallow. The sympathetic and parasympathetic nervous systems are part of the autonomic nervous system. They work to counterbalance each other. The "fight-or-flight" response to danger or stress comes from sympathetic activity. Parasympathetic activity deals with what's often called "rest-and-digest" functions—in other words, the normal activity that your body engages in when you're not in a situation that requires an intense physical reaction.

The lesser petrosal nerve of the glossopharyngeal nerve, which connects to the parotid gland, contains parasympathetic fibers and stimulates the release of saliva, which is called a secretomotor function. This is part of the parasympathetic nervous system because saliva is involved in the digestive process. Problems with the glossopharyngeal nerve can impact all of the processes it's involved with.

Damage to the nerve can be caused by injury or surgery to the head and neck, as well as by strokes, diseases that affect nerve function, or tumors that grow on or compress the nerve.