The glossopharyngeal nerve (IX-9^th) nerve supplies sensation to the deep throat.  This region has significant overlap with the vagus (X-10^th ) nerve, which is also responsible for swallowing.

Figure 1: demonstrates the relationship of the glossopharyngeal and vagus nervese to the brainstem. Compression of the glossopharyngeal and vagus nerves most often occurs directly at the level of the brainstem where it emerges into the fluid space. This is commonly not recognized by inexperienced surgeons.  These nerves are located under and deep to the hearing and balance nerve making access particularly challenging.  A blood vessel(s) could cause the compression or possibly a  vein maybe responsible.

When small vessels cause compression at the origin of glossopharyngeal nerve and the vagus nerve, it results in a severe pain syndrome creating electrical shocks or “knife like stabbing pain” in the deep throat. The pain may radiate and travel into the deep ear as well. The pain is aggravated by swallowing, especially cold liquids and spicy food.  The pain may also come and go with periods of remission but often will progress overtime.

Figure 2:  A small artery is seen (circled area) causing compression of the glossopharyngeal (IX) and vagus(X)  nerves at their origin at the brainstem.

There are many forms of treatment recommended but in general they fall into 3 categories:

1. Medical therapy
2. Ablative therapy
3. Microvascular decompression

Medical Therapy:

Drugs similar to that for trigeminal Neuralgia have been tried for glossopharyngeal neuralgia with little success.  These medications are intended to calm or improve the function of the nerve. In general these are medications often used for seizures of the brain (Tegretol, Dilantin and Lamictal).  Unfortunately these rarely provide consistent relief and may create unwanted side-effects, such as, sedation, lethargy, cognitive impairment amongst others. Under these circumstances patients may wish to consider other therapies.

Ablative Therapy:

These therapies are designed to ablate or selectively destroy specific fibres of the glossopharyngeal nerve.  The procedure consists of a variety of approaches of cutting or sectioning the nerve.  In our experience these are unsuccessful and may close the door for subsequent definitive therapy.

Microvascular Decompression:

This procedure is intended to move the offending vessel and create a cushion or pad between the glossopharyngeal nerve and the upper two branches (fassicles) of the vagus nerve and the offending vessel(s).  The decompression addresses the root cause of glossopharyngeal neuralgia by dealing with vessel that is causing the compression.  The approach involves a minimally invasive keyhole retromastoid approach.  This approach involves making a small incision behind the ear and a key whole opening in the bone. Using the natural space that is created when the cerebrospinal fluid is drained direct access to the glossopharyngeal and vagus nerve and offending vessel is provided.  Using this space there is little need for manipulation of the brain and nerves.  Small pads of Teflon are placed between the nerve and vessel.  Occasionally also treating the Nervus Intermedius may improve the outcome.