Attacks may be triggered by a particular action, such as chewing, swallowing, talking, coughing, or sneezing. 12, 13Īttacks of glossopharyngeal neuralgia are brief and occur intermittently, but they cause excruciating pain similar to trigeminal neuralgia. 1 There is also a pharyngeal-facial variant of Guillian-Barre syndrome involving CN IX, the glossopharyngeal, and the post-infections syndrome of varicella zoster. Occasionally glossopharyngeal neuralgia is caused by a lesion associated with the onset of multiple sclerosis. There are case reports of a schwannoma of the nerve itself, 9, 10 which may also account for symptoms. 3 The cause is rarely a tumor in the brain or neck or by dissection of the carotid artery. Often, its cause is unknown, but sometimes glossopharyngeal neuralgia results from an abnormally positioned artery that compresses the CN IX near where it exits the brain stem. It usually begins after age 40 and occurs more often in men. Glossopharyngeal neuralgia is a rare disorder. 5, 7, 8 The same mechanism likely accounts for swallow syncope, where consciousness is lost during or immediately after a swallow even though there is no pain. In glossopharyngeal neuralgia, the nerve dysfunction induces a reflex syndrome of pain, bradycardia (or actual stoppage of the heart temporarily), and syncope. Glossopharyngeal neuralgia can be associated with fainting in 1 to 2 percent of affected people due to its reflex association with CN X. Glossopharyngeal neuralgia and “swallow syncope.” The most important and common syndrome caused by a disorder of the CN IX is glossopharyngeal neuralgia. Lesions in the motor portion may be reflected in some difficulty swallowing, although the gag reflex itself may be normal. Tactile sense in the pharynx is normally rolled into the gag reflex, but can be tested using light touch and direct inquiry about problems with aspiration. The sensory function of the nerve can be tested by evaluating taste (sweetness) on the posterior one-third of the tongue. Lesions to the CN IX are often accompanied by lesions to the CN X. The glossopharygeal nerve has a communicating branch to the vagus nerve (CN X). The cell bodies of the neurons forming the lower motor neuron portion of the CN IX, which innervates the stylopharynegeus muscle, are located in the nucleus ambiguous of the medulla. The nerve supplies parasympathetic fibers to the parotid gland that originate in the inferior salivary nucleus. Parasympathetic visceral fibers to the CN-IX arise in the carotid bodies of the neck. The sensory division of the nerve projects to the solitary nucleus (taste). 1– 5 The sensory division receives general sensory fibers from the tonsils, pharynx, middle ear, and the posterior one-third of the tongue, as well as taste fibers from the posterior third of the tongue. CN IX is innervated bilaterally and has sensory, parasympathetic, and motor components. This article reviews these and other syndromes related to cranial nerves IX through XII that might be seen by psychiatry.Īnatomy. Supranuclear lesions of cranial nerve XII are involved in pseudobulbar palsy and ALS, and lower motor neuron lesions of cranial nerve XII can also be present in bulbar palsy and in ALS patients who also have lower motor neuron involvement. Finally, unilateral hypoglossal (craniel nerve XII) nerve palsy is one of the most common mononeuropathies caused by brain metastases. A cervical lesion to the nerve roots of the spinal accessory nerve (craniel nerve XI) can cause a cervical dystonia, which sometimes is misdiagnosed as a dyskinesia related to neuroleptic use. Vagus nerve funtion (craniel nerve X) can be compromised in schizophrenia, bulimia, obesity, and major depression. Also, swallowing function occasionally is compromised in a rare but disabling form of tardive dyskinesia called tardive dystonia, because the upper motor portion of the glossopharyngel nerve projects to the basal ganglia and can be affected by lesions in the basal ganglia. To summarize briefly, the most important and common syndrome caused by a disorder of the glossopharyngeal nerve (craniel nerve IX) is glossopharyngeal neuralgia. Neuroanatomy, cranial nerve 9 (glossopharyngeal).This article concludes the series on cranial nerves, with review of the final four (IX–XII). Neuroanatomy, cranial nerve 12 (hypoglossal). Neuroanatomy, cranial nerve 10 (vagus nerve). Neuroanatomy, cranial nerve 1 (olfactory). Neuroanatomy, cranial nerve 11 (accessory). Neuroanatomy, cranial nerve 8 (vestibulocochlear). You can learn more about how we ensure our content is accurate and current by reading our editorial policy. We link primary sources - including studies, scientific references, and statistics - within each article and also list them in the resources section at the bottom of our articles. Medical News Today has strict sourcing guidelines and draws only from peer-reviewed studies, academic research institutions, and medical journals and associations.
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