презентация Glossofaryngeas

1. TheThe glossopharyngeal nerveglossopharyngeal nerve is the ninth ofis the ninth of
twelve pairs oftwelve pairs of cranial nervescranial nerves. It exits the. It exits the
brainstem out from the sides of the upperbrainstem out from the sides of the upper
medullamedulla, just rostral (closer to the nose) to the, just rostral (closer to the nose) to the
vagusvagus nervenerve..

2. FunctionsFunctions
 There are a number of functions of the glossopharyngeal nerve:There are a number of functions of the glossopharyngeal nerve:
 It receivesIt receives sensory fibressensory fibres from the posterior one-thirdfrom the posterior one-third
of theof the tonguetongue, the, the tonsilstonsils, the, the pharynxpharynx, the, the middle earmiddle ear
and theand the carotid bodycarotid body..
 It suppliesIt supplies parasympatheticparasympathetic fibres to thefibres to the parotid glandparotid gland
via thevia the otic ganglionotic ganglion..
 It suppliesIt supplies motor fibresmotor fibres toto stylopharyngeus musclestylopharyngeus muscle
 It contributes to theIt contributes to the pharyngeal plexuspharyngeal plexus..

3. nucleusnucleus
The glossopharyngeal nerve, being mostly sensory, does not have aThe glossopharyngeal nerve, being mostly sensory, does not have a
cranial nerve nucleuscranial nerve nucleus of its own. Instead it must project into manyof its own. Instead it must project into many
different structures in the brainstem:different structures in the brainstem:
 Solitary nucleusSolitary nucleus: Taste from the posterior one-third of the tongue and: Taste from the posterior one-third of the tongue and
information frominformation from carotid baroreceptorscarotid baroreceptors andand carotid body chemoreceptorscarotid body chemoreceptors
 Spinal nucleus of the trigeminal nerveSpinal nucleus of the trigeminal nerve: Visceral pain as well as somatic: Visceral pain as well as somatic
sensory fibers from the skin of the outer ear.sensory fibers from the skin of the outer ear.
 Nucleus ambiguusNucleus ambiguus: The: The lower motor neuronslower motor neurons for thefor the stylopharyngeusstylopharyngeus
muscle.muscle.
Inferior salivatory nucleusInferior salivatory nucleus:: ParasympatheticParasympathetic input to theinput to the parotidparotid andand
mucous glandsmucous glands

4. PathPath
 From theFrom the medulla oblongatamedulla oblongata, the glossopharyngeal nerve passes laterally, the glossopharyngeal nerve passes laterally
across theacross the flocculusflocculus, and leaves the skull through the central part of the, and leaves the skull through the central part of the
jugular foramenjugular foramen, in a separate sheath of the, in a separate sheath of the duradura matermater, lateral to and in, lateral to and in
front of the vagus and accessory nerves. Within the jugular foramen, thefront of the vagus and accessory nerves. Within the jugular foramen, the
glossopharyngeal nerve forms the superior ganglion (the glossopharyngealglossopharyngeal nerve forms the superior ganglion (the glossopharyngeal
neve is also associated with an inferior ganglion).neve is also associated with an inferior ganglion).
 In its passage through the jugular foramen, it grooves the lower border of theIn its passage through the jugular foramen, it grooves the lower border of the
petrouspetrous partpart of theof the temporal bonetemporal bone; and, at its exit from the; and, at its exit from the skullskull, passes forward, passes forward
between thebetween the internal jugular veininternal jugular vein andand internal carotid arteryinternal carotid artery. It descends in front of. It descends in front of
the latter vessel, and beneath thethe latter vessel, and beneath the styloidstyloid processprocess and the muscles connected with it,and the muscles connected with it,
to the lower border of theto the lower border of the stylopharyngeusstylopharyngeus. It then curves forward, forming an arch. It then curves forward, forming an arch
on the side of the neck and lying upon theon the side of the neck and lying upon the stylopharyngeusstylopharyngeus andand
middle pharyngeal constrictormiddle pharyngeal constrictor muscle. From there it passes under cover of themuscle. From there it passes under cover of the
hyoglossushyoglossus muscle, and is finally distributed to themuscle, and is finally distributed to the palatine tonsilpalatine tonsil, the mucous, the mucous
membrane of the fauces and base of the tongue, and the mucous glands of themembrane of the fauces and base of the tongue, and the mucous glands of the
mouth.mouth.

5. BranchesBranches
1. Tympanic1. Tympanic
2. Stylopharyngeal2. Stylopharyngeal
3. Tonsillar3. Tonsillar
4. Nerve to carotid sinus4. Nerve to carotid sinus
5. Branches to the posterior third of tongue5. Branches to the posterior third of tongue
6. Lingual branches6. Lingual branches
7. A communicating branch to the Vagus nerve7. A communicating branch to the Vagus nerve
Note: The glossopharyneal nerve contributes in theNote: The glossopharyneal nerve contributes in the
formation of the pharyngeal plexus along with the vagusformation of the pharyngeal plexus along with the vagus
nerve.nerve.

6. Testing the glossopharyngeal nerveTesting the glossopharyngeal nerve
 The gag reflex is absent in patients withThe gag reflex is absent in patients with
damage to the glossopharyngeal nerve as it isdamage to the glossopharyngeal nerve as it is
responsible for the afferent limb of the reflexresponsible for the afferent limb of the reflex

7. Testing the glossopharyngeal nerveTesting the glossopharyngeal nerve
 The gag reflex is absent in patients withThe gag reflex is absent in patients with
damage to the glossopharyngeal nerve as it isdamage to the glossopharyngeal nerve as it is
responsible for the afferent limb of the reflexresponsible for the afferent limb of the reflex