Glossopharyngeal neuralgia is a condition characterized by recurring episodes of severe pain in the tongue, throat, ear, and area near the tonsils. The painful episodes may last from a few seconds to few minutes.
Glossopharyngeal neuralgia is a rare disorder. It usually begins after the age of 40, and is more common in men. The symptoms include severe pain in areas connected to the ninth cranial nerve (glossopharyngeal nerve). These areas include the back of the throat, tonsillar region, the back third of the tongue, back of the nose, larynx, and the ear. This nerve is involved in the movement of the tongue and transfers important information from the brain to the tongue, the throat and then back again.
Although brief and intermittent, the attacks cause excruciating pain. The attacks are sometimes be triggered by a particular action, such as chewing, swallowing, speaking, coughing, or sneezing.
What Causes Glossopharyngeal Neuralgia?
Glossopharyngeal neuralgia is caused by irritation of the ninth cranial nerve. In some cases, the source of irritation is never found. We do know that one potential cause of the condition is an abnormally positioned artery that puts pressure on (compresses) the glossopharyngeal nerve. We have also observed that the condition can be caused by an unusually long, pointed bone at the base of the skull (styloid process) that causes the compresses the nerve. AS a neurosurgeon, I'm typically looking for one of these possible causes:
- Blood vessels pressing down on the glossopharyngeal nerve
- Growths or lesions at the base of the skull
- an unusually long styloid process
- Tumors or infections of the throat and mouth
The condition is very similar to trigeminal neuralgia and is sometimes misdiagnosed by physicians who have less experience with the condition*. TN affects the except that TN affects the5th cranial nerve..., not the 9th.
How is Glossopharyngeal Neuralgia Diagnosed?
A variety of tests may be performed to identify problems. The test may include MRI’s, CT Scans, or X-rays. The condition can sometimes be identified by a physical "trigger" where the doctor touches the area of the nerve. If this test suggests GPN, then an MRI will almost certainly be indicated.
How is GPN treated?
The first line of defense is almost always with drugs..., typically carbamazepine, gabapentin, or pregabalin. There are reports of NSAIDs being effective, but the information is sketchy and not well supported in medical literature.
Unfortunately, patients often build up a tolerance for these drugs and their effectivenesss diminishes.
Nerve Blocks are administered with a needle and involve the injection of local anesthetics, steroids, or neurolytic agents (phenol, alcohol, glycerol, etc.). The block is often a part of the confirmation of a diagnosis of GPN.
Although drugs are sometimes effective in treatment, surgery may be required for permanent relief from the pain. Surgery is considered effective for cases that do not benefit from medications. When the pain results from an abnormally positioned artery pressing on a cranial nerve, the pain can be relieved by a surgical procedure called microvascular decompression.
The glossopharyngeal nerve is separated from the artery that is compressing it by placing a small sponge between them. In order to access the nerve/artery compression, a small hole is cut in the skull, and then the brain is lifted slightly to expose the nerve.
The procedure itself is very similar to the surgical treatment of trigeminal neuralgia. It is critical that this surgery be performed by an experienced and well trained neurosurgeon.
You can learn more about glossopharyngeal neuralgia at the European Neurology Journal.
Princeton Brain & Spine neurosurgeon Mark McLaughlin, M.D. trained with Peter Jannetta, M.D., the "father" of modern microvascular decompression surgery for trigeminal neuralgia, hemifacial spasm, glossopharyngeal neuralgia, and other cranial nerve rhizopathies. Dr. McLaughlin worked closely with Dr. Jannetta in the ongoing research, and was the lead author of the paper "Microvascular decompression of cranial nerves: lessons learned after 4400 operations" published in the Journal of Neurosurgery in January 1999. On PUBMED
* NIH An uncommonly common: Glossopharyngeal neuralgia