Glossopharyngeal Neuralgia
Glossopharyngeal neuralgia is a rare cranial neuralgia characterised by severe, unilateral, electric shock-like, paroxysmal pain in the throat, base of the tongue and ear, in the distribution of the ninth cranial nerve (glossopharyngeal nerve). First-line treatment is with anticonvulsants; in refractory cases, microvascular decompression is the main surgical option.
最終更新: 2026-06-07
Definition
Glossopharyngeal neuralgia (GPN) is a rare cranial neuralgia presenting with severe, unilateral and paroxysmal (sudden-onset, sudden-offset) pain localised to the distribution of the ninth cranial nerve. It is far less common than trigeminal neuralgia. The pain is felt in the tonsillar region, base of the tongue, oropharynx and the ipsilateral deep ear. It is electric shock-like or stabbing and lasts from seconds to a few minutes.
Causes and Pathophysiology
In most cases the cause is compression of the nerve by a blood vessel (most often the posterior inferior cerebellar artery) at the root entry zone where the ninth nerve leaves the brainstem (neurovascular compression). Pulsatile compression damages the nerve myelin and leads to abnormal, spontaneous discharges. In the primary (idiopathic) form there is no structural lesion. Secondary causes include cerebellopontine angle tumours (schwannoma, meningioma, epidermoid cyst), jugular foramen lesions, multiple sclerosis and oropharyngeal tumours. In a subset of patients a vagal (tenth nerve) component is present; in these cases the pain may be accompanied by bradycardia, hypotension and syncope.
Symptoms
The pain is sharp, electric shock-like and unilateral; it is localised to the tonsillar fossa, base of the tongue, soft palate, oropharynx and the ipsilateral deep ear. The most common trigger is swallowing; speaking, laughing, coughing and chewing can also provoke attacks. The period between attacks is usually pain-free. Because swallowing triggers the pain, patients may avoid eating, which can lead to weight loss. In cases with a vagal component, bradycardia, low blood pressure and fainting may occur during the pain.
Diagnosis
The diagnosis is clinical: unilateral, paroxysmal, electric shock-like pain in the tonsillar fossa-tongue base-ear region, provoked by triggers such as swallowing, is essential. Reproduction of pain by stimulating the trigger zone on oropharyngeal examination supports the diagnosis. Contrast-enhanced brain MRI with high-resolution thin-slice sequences (FIESTA/CISS) is mandatory to exclude secondary causes; MR angiography demonstrates the neurovascular relationship. If cardiovascular symptoms are present, ECG and Holter monitoring are performed. Temporary disappearance of pain after applying topical local anaesthetic to the trigger zone supports the diagnosis. The differential diagnosis includes trigeminal neuralgia, Eagle syndrome and oropharyngeal pathology.
Medical (Conservative) Treatment
As in trigeminal neuralgia, first-line treatment is with anticonvulsants. Carbamazepine is the first choice; it is started at a low dose and increased gradually. Monitoring is required because of its side effects (dizziness, drowsiness, hyponatraemia, changes in blood counts and liver enzymes). Oxcarbazepine is a frequently preferred alternative because it is better tolerated. Gabapentin, pregabalin and baclofen may be used as adjuncts or alternatives. Drug therapy initially controls the pain in a substantial proportion of patients, but its efficacy may decline over time and side effects may limit treatment.
Surgical and Interventional Treatment
Surgery is considered in patients refractory to drug therapy, with intolerable side effects, or with syncope due to a vagal component. Microvascular decompression (MVD) is the gold-standard surgery: through a posterior fossa craniotomy, the vessel compressing the ninth nerve is separated from it and a soft insulator (Teflon) is interposed. The success rate is high and it offers a durable solution; accompanying cardiovascular symptoms also improve substantially. Possible complications include transient or permanent swallowing/voice disturbance, cerebrospinal fluid leak and meningitis. In elderly or high-risk patients unsuitable for surgery, stereotactic radiosurgery (Gamma Knife) is a non-invasive option; its effect is delayed and its success rate is lower than MVD. In cases with severe bradycardia-asystole, a pacemaker may be required.
Prognosis
Because it is a rare disease, diagnosis is often delayed. Drug therapy controls the pain in most patients initially, but it may become refractory over time. Microvascular decompression can provide high and durable success in refractory cases. Cases with a vagal component require a more urgent approach because of the risk of syncope and cardiac complications. The treatment plan is individualised for each patient, and no outcome can be guaranteed in advance.
参考文献
- Greenberg MS. Greenberg's Handbook of Neurosurgery. 10th ed. Thieme; 2023:1874-1875.
- Singh PM, Kaur M, Trikha A. An uncommonly common: glossopharyngeal neuralgia. Ann Indian Acad Neurol. 2013;16(1):1-8.
- Headache Classification Committee of the International Headache Society (IHS). The International Classification of Headache Disorders, 3rd edition. Cephalalgia. 2018;38(1):1-211.
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