Glossopharyngeal Neuralgia
Introduction
Glossopharyngeal Neuralgia is similar to Trigeminal Neuralgia but is much less common. The shooting pain occurs in the throat, tonsil region, and base of the tongue on one side. The pain may be spontaneous or triggered by swallowing.
Like Trigeminal Neuralgia, the condition is caused most frequently by an abnormal looping artery impinging against the Glossopharyngeal nerve (cranial nerve 9) at the root entry zone into the brain stem. Although an MRI scan is indicated to rule out the presence of a tumor as a cause of Glossopharyngeal Neuralgia, the blood vessel is usually difficult to see even when present. The best diagnostic test is the topical application of cocaine or viscous xylocaine to the throat and tonsilar fossa on the affected side, which should provide temporary pain relief and can be used to allow the patient to eat as well as to confirm the diagnosis.
Treatment
Initial treatment of Glossopharyngeal Neuralgia is medical with carbamazepine (Tegretol®) and gabapentin (Neurontin®) being the medications of choice. Unfortunately, these medications are not as effective for Glossopharyngeal Neuralgia as they are for Trigeminal Neuralgia. As a result, the majority of patients require Microvascular Ddecompression (MVD) which is the only advisable surgical procedure.
Microvascular Decompression
This procedure involves entering the skull behind the ear and locating a loop of blood vessel contacting the root entry zone of the 9th cranial nerve. The blood vessel is lifted away and padded a safe distance off the nerve with a Teflon® felt sponge. The incision is closed watertight. Most patients will experience immediate relief of their pain after this procedure. The first night post-operatively is spent in the intensive care unit for observation. Most people will be discharged home by the third post-operative day.