Glossopharyngeal neuralgia is rare, more commonly affecting men, usually after age 40.
Glossopharyngeal neuralgia sometimes results from nerve compression by an aberrant, pulsating artery similar to that in trigeminal neuralgia and hemifacial spasm. The nerve may be compressed in the neck by an elongated styloid process (Eagle syndrome).
Rarely, the cause is a tumor in the cerebellopontine angle or the neck, a peritonsillar abscess, a carotid aneurysm, or a demyelinating disorder.
Often, no cause is identified.
As in trigeminal neuralgia, paroxysmal attacks of unilateral brief, excruciating pain occur spontaneously or are precipitated when areas innervated by the glossopharyngeal nerve are stimulated (eg, by chewing, swallowing, coughing, talking, yawning, or sneezing). The pain, lasting seconds to a few minutes, usually begins in the tonsillar region or at the base of the tongue and may radiate to the ipsilateral ear.
Occasionally, increased activation of the vagus nerve due to its connections with the glossopharyngeal nerve causes sinus arrest with syncope; episodes may occur daily or once every few weeks.
Diagnosis of glossopharyngeal neuralgia is clinical.
Glossopharyngeal neuralgia is distinguished from trigeminal neuralgia by the location of the pain. Also, in glossopharyngeal neuralgia, swallowing or touching the tonsils with an applicator tends to precipitate pain, and applying lidocaine to the throat temporarily eliminates spontaneous or evoked pain.
MRI is done to exclude tonsillar, pharyngeal, and cerebellopontine angle tumors and metastatic lesions in the anterior cervical triangle. X-rays or CT can be done to look for an elongated styloid process below the ear, which could be compressing the nerve. Local nerve blocks done by an otolaryngologist can help distinguish between carotidynia, superior laryngeal neuralgia, and pain caused by tumors.
Treatment of glossopharyngeal neuralgia is the same as that for trigeminal neuralgia (eg, oxcarbazepine, baclofen, lamotrigine, gabapentin, phenytoin, amitriptyline).
If oral drugs are ineffective, local anesthetics can provide relief. For example, topical cocaine applied to the pharynx may provide temporary relief. However, surgery to decompress the nerve from a pulsating artery (microvascular decompression) may be necessary. If pain is restricted to the pharynx, surgery can be restricted to the extracranial part of the nerve. If pain is widespread, surgery must involve the intracranial part of the nerve.
The pain of glossopharyngeal neuralgia is similar to that of trigeminal neuralgia.
Distinguish glossopharyngeal neuralgia from trigeminal neuralgia based on the pain's location and response to touching and to lidocaine applied to the pharynx.
Do MRI to distinguish glossopharyngeal neuralgia from tumors and metastatic lesions.
Treat as for trigeminal neuralgia (usually with antiseizure drugs).
If drugs are ineffective, try local anesthetics, but microvascular decompression may be necessary.