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.
Anatomy and Physiology of the Autonomic Nervous System
Kenneth J. Broadley in Autonomic Pharmacology, 2017
The parasympathetic innervation arises from the medulla, the Vllth cranial nerve synapsing in the submandibular ganglia before reaching the submandibular and sublingual salivary glands. The IXth cranial nerve synapses in the otic ganglion before innervating the largest of the salivary glands, the parotid gland. The nerve endings penetrate the basal membrane and come into direct contact with the acinar cells. Parasympathetic stimulation produces a profuse watery saliva rich in enzymes to aid digestion. Although Ach is the primary parasympathetic neurotransmitter, the neuropeptide VIP is also found in parasympathetic neurones supplying the salivary glands, where it is involved in the vasodilator response (see Chapter 12).
SBA Answers and Explanations
Vivian A. Elwell, Jonathan M. Fishman, Rajat Chowdhury in SBAs for the MRCS Part A, 2018
The secreto-motor supply to the parotid (for secretion of saliva) is by way of parasympathetic fibres of the glossopharyngeal nerve, synapsing in the otic ganglion and relaying onwards to the parotid gland through the auriculotemporal nerve. The importance of knowing this lies in a phenomenon known as Frey’s syndrome which may occur, not infrequently, following parotid surgery, or penetrating trauma to the parotid gland. It is caused by misdirected reinnervation of the auriculotemporal nerve fibres to the sweat glands in the facial skin following its injury. The patient may complain of gustatory sweating (i.e., a stimulus intended for saliva production produces sweating instead).
Beyond chronic migraine: a systematic review and expert opinion on the off-label use of botulinum neurotoxin type-A in other primary headache disorders
Published in Expert Review of Neurotherapeutics, 2021
Andreas A. Argyriou, Dimos-Dimitrios Mitsikostas, Elisa Mantovani, Michail Vikelis, Stefano Tamburin
Four open-label studies, which explored BoNTA injection in head/neck muscles [65,68] and the sphenopalatine ganglion [66,67], documented some improvement, with a consistent number of side effects in the latter site of injection. A single open-label study of otic ganglion BoNTA injection reported mild adverse events, but no significant effect on CH outcomes [69]. Taken together, these studies indicate BoNTA as a possible therapeutic strategy for intractable CH, but the need for RCTs to shed light on this topic. Indeed, the pathogenesis of CH attacks rely upon CNS mechanisms in the hypothalamus [7] and blocking of peripheral pain mediators might not be sufficient to reduce their incidence.
Galcanezumab for the prevention of cluster headache
Published in Expert Opinion on Biological Therapy, 2020
Luca Giani, Alberto Proietti Cecchini, Massimo Leone
After a correct diagnosis of CH, nearly all the patients are prescribed preventive treatments [16]. Due to the unsatisfactory level of evidence, drugs for CH prevention are commonly prescribed as off-label drugs. More than 20–40% of CH patients rate ‘poor’ current preventive treatments as verapamil, steroids, and lithium; and are even more unsatisfied with the other drugs [17]. The unmet need is high for these patients. More than 30% of CCH patients do not respond to the preventive treatments indicated in current treatment guidelines [17]. Usually, these drugs need high dosages, with a consequent low tolerability profile potentially leading to discontinuation [18,19]. Due to the shortcoming of preventative therapies, patients often seek help from costly and unproven alternative approaches such as acupuncture, herbal treatment, chiropractic treatment [4], illicit psychoactive substances [16]. Almost a quarter of patients undergo useless invasive procedures, such as sinus surgery and teeth removal [3,6]. Semi-invasive and invasive neurostimulation treatments have been developed including vagus nerve stimulation [20,21], stimulation of sphenopalatine ganglion [22], occipital nerve stimulation [23,24], and deep brain stimulation [25,26]. Ongoing active or recruiting trials for preventive treatments in CH (as of 2020/06/10, source http://clinicaltrials.gov/) involve the use of Sphenopalatine Ganglion Pulsed Radiofrequency (NCT03567590), Lysergic Acid (NCT03781128), Botulinum Toxin Type A Blockade of the Sphenopalatine Ganglion (NCT03944876), Civamide (NCT01341548, not yet recruiting), Psilocybin (NCT04280055 & NCT02981173), L-cysteine (NCT02310828), greater occipital nerve injection with Methylprednisolone (NCT04014634). Results of the recently completed trials with Botulinum Toxin Type A Block of the Otic Ganglion (NCT03066635), Continuous Positive Airway Pressure (CPAP, NCT03397563) and Occipital Nerve Stimulation (NCT01151631) are awaited.
Related Knowledge Centers
- Ciliary Ganglion
- Eustachian Tube
- Glossopharyngeal Nerve
- Infratemporal Fossa
- Mandibular Nerve
- Parasympathetic Ganglia
- Pterygopalatine Ganglion
- Parotid Gland
- Foramen Ovale
- Submandibular Ganglion