26 - Glossopharyngeal Nerve Block: Intraoral Approach

Abstract

The glossopharyngeal nerve exits from the jugular foramen in proximity to the vagus and accessory nerves and the internal jugular vein. The glossopharyngeal nerve contains both motor and sensory fibers. The motor fibers innervate the stylopharyngeus muscle. The sensory portion of the nerve innervates the posterior third of the tongue, palatine tonsil, and mucous membranes of the mouth and pharynx. Special visceral afferent sensory fibers transmit information from the taste buds of the posterior third of the tongue. Information from the carotid sinus and body that helps control blood pressure, pulse, and respiration is carried via the carotid sinus nerve, which is a branch of the glossopharyngeal nerve. Parasympathetic fibers pass via the glossopharyngeal nerve to the otic ganglion. Postganglionic fibers from the ganglion carry secretory information to the parotid gland. Glossopharyngeal nerve block via the intraoral approach is used when anatomic distortion secondary to tumor or prior surgery precludes the use of the extraoral approach. Glossopharyngeal nerve block can be used for prognosis and diagnosis as well as for treatment of acute pain emergencies such as glossopharyngeal neuralgia. This technique is also useful in the palliation of cancer pain.