ENTRIES A–Z
Philip Winn in Dictionary of Biological Psychology, 2003
The solitary tract, in which the nucleus of the solitary tract sits, is a band of fibres near the midline at the top of medulla oblongata. The nuclei themselves are positioned like a pair of cigars laid at the top of the medulla, within the solitary tract, running from front to back. The two nuclei almost converge together at the midline at their most caudal points, but angle outwards slightly as they run forward, forming a V shape together. The front section of the nucleus of the solitary tract is sometimes referred to as the gustatory or taste nucleus. Taste sensory neurons project from the tongue and palate to this section of the nucleus of the solitary tract through two cranial nerves. The FACIAL NERVE (seventh cranial nerve) carries fibres from taste receptors located in the front and middle regions of the tongue. The GLOSSOPHARYNGEAL NERVE (ninth cranial nerve) carries fibres from receptors located at the back of the tongue and the palate. Both nerves project to gustatory neurons within the anterior one-third of the nucleus of the solitary tract. Within this nucleus, an array of neurotransmitters are found: glutamate, GABA, ENKEPHALIN, CHOLECYSTOKININ, and NEUROPEPTIDE Y, among others.
Examination of the Nervous System
Julian L Burton, Guy Rutty in The Hospital Autopsy, 2010
The first muscle encountered is the sternomastoid. This, supplied by its spinal accessory nerve, is divided at the mid-point. Samples may be taken and the cut ends then reflected upwards and downwards, thus exposing the carotid sheath. At this point, if required, the two bellies of the digastric muscle can be dissected out and sampled. The anterior belly is innervated by the trigeminal nerve and the posterior belly by the facial nerve. The carotid sheath containing the common and internal carotid arteries, internal jugular vein and the vagus nerve can now be explored. The internal carotid artery and vagus nerve are dissected upwards up to their point of entry into the skull. The swelling of the vagus nerve below the skull denotes the position of its inferior ganglion. The hypoglossal and accessory nerves emerge close to the vagus at this point. The glossopharyngeal nerve is to be found between the internal carotid artery and the internal jugular vein running towards the pharynx.
Clinical Neuroanatomy
John C Watkinson, Raymond W Clarke, Christopher P Aldren, Doris-Eva Bamiou, Raymond W Clarke, Richard M Irving, Haytham Kubba, Shakeel R Saeed in Paediatrics, The Ear, Skull Base, 2018
The glossopharyngeal nerve emerges from the brainstem in line with the vagus and accessory nerves and exits from the skull via the jugular foramen. It descends between the jugular vein and carotid artery, picking up sympathetic fibres from the carotid plexus as it loops forwards and medially to reach the soft tissues of the oropharynx, posterior tongue and palate. In its course, it gives off the lesser petrosal nerve conveying the secretomotor fibres for the parotid gland to the otic ganglion. An important nerve, the carotid branch, conveys chemoceptor and stretch reflex information, respectively, from the carotid body and carotid sinus centrally for respiratory and circulatory reflex function. The final branches of the glossopharyngeal nerve are the pharyngeal, tonsillar and lingual branches, conveying general sensation and taste sensation from the posterior third of the tongue and oropharynx.
Glossopharyngeal neuralgia as initial symptom in combined hyperactive dysfunction syndrome: case report
Published in British Journal of Neurosurgery, 2023
Pelin Kuzucu, Tolga Türkmen, Göktuğ Ülkü, Mesut Emre Yaman, Şükrü Aykol
Microvascular decompression was performed via the retrosigmoid approach. Superior cerebellary artery (SCA) was the offending vessel anterosuperior to the trigeminal nerve exit zone (Figure 2(a)). After meticulous dissection of the nerve from the vessel, a small piece of shredded Teflon was placed between these two structures (Figure 2(d)). Compression caused by the vein of the middle cerebellary peduncle was seen to the facial nerve exit zone (Figure 2(b)). The vein and the nerve were separated from each other, without sacrificing the vein. A Teflon sponge was placed between the vein and the nerve (Figure 2(e)). The arachnoid dissection was advanced inferiorly to visualize the lower cranial nerves. The glossopharyngeal nerve was compressed by anterior inferior cerebellary artery (AICA) (Figure 2(c)). Teflon was placed between the nerve and artery (Figure 2(f)). Postoperatively the patient was without any neurological deficit. Immediately after surgery, the patient expressed complete relief from all of his previous symptoms. He remained neurologically intact and asymptomatic up to his 1-year follow-up.
The carotid body and associated tumors: updated review with clinical/surgical significance
Published in British Journal of Neurosurgery, 2019
Nasir Butt, Woong Kee Baek, Stefan Lachkar, Joe Iwanaga, Asma Mian, Christa Blaak, Sameer Shah, Christoph Griessenauer, R. Shane Tubbs, Marios Loukas
Horner’s syndrome, carotid body syndrome, and sensorineural symptoms such as hearing loss and tinnitus are far less common but have been reported. In 2010, Gama and Cabral reported a case of a 46-year-old woman who presented with sudden and repeated episodes of syncope.21 The CBT was stretching the baroreceptors of the carotid sinus, which is located in the wall of the internal carotid artery 38 mm above the bifurcation. This, in turn, resulted in paroxysmal overstimulation of the parasympathetic system. And the ensuing bradycardia led to the syncopal episodes. Athanasios et al.12 reported a case of a 57-year-old man with a painless left-sided neck mass that had been present for several years. His presenting symptoms included dysphagia, alteration of taste, and pain on palpation of the left auricle.12 This patient’s clinical manifestation was due to a CBT’s direct impingement on the lingual branch of the glossopharyngeal nerve and the auricular branch of the vagus nerve, which innervates the posterior third of the tongue and supplies sensory fibers to the skin of external acoustic meatus, respectively. In both cases, surgical removal of the tumors successfully restored the functional deficits. The patients remained asymptomatic at the 2-year follow-up.
Comparison between landmark and ultrasound-guided percutaneous peristyloid glossopharyngeal nerve block for post-tonsillectomy pain relief in children: a randomized controlled clinical trial
Published in Egyptian Journal of Anaesthesia, 2022
Abdelrhman Alshawadfy, Ahmed A. Ellilly, Ahmed M. Elewa, Wesam F. Alyeddin
Several studies have described glossopharyngeal nerve block in pain therapy or post-operative analgesia using different techniques; however, the current trial is novel in comparing the landmark techniques against ultrasound techniques in pediatric age group undergoing tonsillectomy with a primary outcome of time to first analgesic requirement and secondary outcomes giving a spotlight on easiness and anesthetist satisfaction. Earlier trials of glossopharyngeal nerve block used the intraoral technique [8], and some performed the para-pharyngeal not the peristyloid technique in cadaver and volunteer sonoanatomy study [9]. Some studies compared the extraoral and intraoral routes of glossopharyngeal nerve block for pain relief in patients with carcinoma of the tongue, and some trials used extra oral glossopharyngeal nerve block in glossopharyngeal neuralgia [9–11].
Related Knowledge Centers
- Brainstem
- Cranial Neural Crest
- Jugular Foramen
- Embryo
- Medulla Oblongata
- Cranial Nerves
- Nose
- Vagus Nerve
- Basal Plate
- Flocculus