Because both of these cranial nerves are intimately related, they are described here together. The glossopharyngeal nerve has a sensory and motor component. The motor fibers develop from the nucleus uncertain situated in the horizontal the main medulla. Combined with vagus and accessory nerves, they leave the skull through the jugular foramen. They source the stylopharyngeus muscle whose purpose is to elevate the pharynx. Autonomic efferent fibers of the glossopharyngeal nerve develop from the poor salivatory nucleus. The preganglionic fibers go to the otic ganglion through the reduced light petrosal nerve. and postganglionic fibers move across the auriculotemporal branch of the sixth nerve to achieve to reach the Parotid gland. The nuclei of the sensory fibers of the glossopharyngeal nerve are situated in the petrous ganglion which lies within the petrous bone below the jugular foramen and also the remarkable ganglion, which will be small. The exteroceptive fibers source the faucial tonsils, posterior wall of the pharynx, the main smooth palate, and taste sensations from the posterior next to the tongue.
The vagus: Here is the best among most of the cranial nerves. The motor fibers develop from the nucleus ambiguous and source most of the muscles of the pharynx, smooth palate, and larynx, except for tensor veli palatine and stylopharyngeus. The parasympathetic fibers develop from the dorsal efferent nucleus and leave the medulla as preganglionic fibers of the craniosacral part of the autonomic worried system. These fibers end on ganglia near the viscera which they source by post-ganglionic fibers.
They are parasympathetic in function. Therefore vagal stimulation produces bradycardia, bronchial constriction, the release of gastric and pancreatic liquid, and increased peristalsis. The sensory part of the vagus has its nuclei in the jugular in ganglion and ganglion nodosum. The vagus holds sensations from the posterior aspect of the additional auditory meatus and surrounding pinna and pain experienced from the dura mater lining the posterior cranial fossa. vcfs
Testing: It is much better to test the 9th and 10th nerve features together as they are influenced frequently together. Ask for signs like dysphagia, dysarthria, nasal regurgitation of liquids, and hoarseness of voice. The motor portion is tried by analyzing the uvula when the individual is designed to open his mouth. The Uvula is generally in the midline. In unilateral vagal paralysis, the palatal arch is compressed and lowered ipsilaterally. On phonation, the uvula deviates to the standard side.
The fun reflex or the pharyngeal reflex is elicited by making use of a stimulus, like a tongue blade or cotton to the posterior pharyngeal wall or tonsillar region. If the reflex occurs, you will see elevation and contraction of the pharyngeal musculature followed closely by retraction of the tongue. The afferent arch of this reflex is subserved by the glossopharyngeal whilst the efferent is through the vagus. That reflex is missing in either 9th or 10th nerve lesions. Test for general sensations over the posterior pharyngeal wall, smooth palate and faucial tonsils, and taste over the posterior next to the tongue. These are impaired in glossopharyngeal paralysis.
Separated involvement of either nerve is rare and frequently they are included together, usually, the eleventh and twelfth nerves may also be affected. Glossopharyngeal neuralgia resembles trigeminal neuralgia, but it is not as common. It occurs as paroxysmal extreme pain originating in the neck from the tonsillar fossa.
It might be associated with bradycardia and in such cases, it is called vegoglossopharyngeal neuralgia. A test of phenytoin or carbamazepine is normally efficient in treating pain. Mind base wounds like motor neuron infection, general wounds such for instance horizontal medullary infarction or bulbar poliomyelitis make a difference in these nerves together leading to bulbar palsy. Rear fossa tumors and basal meningitis might include these nerves outside the mind stem. Total bilateral vagal paralysis is incompatible with life. Engagement of the recurrent laryngeal nerves, particularly the left, occurs in thoracic wounds and this produces only hoarseness of style without dysphagia