Facial nerve+ MLB +V.O.T pathways Flashcards
(53 cards)
بسم الله الرحمن الرحيم
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The nerve of 2nd phrayngeal arch
Facial nerve CN7 supplying muscles developed from mesoderm of 2nd pharyngeal arch
Facial nerve is mixed nerve fromed of,,,,,,,,,,+,,,,,,,called(…..)
large motor root + small sensory root called nervus intermedius
Sensory root of Facial nerve also supplies …..+……+…… by its ,,,,,,, fibers
Submandibular + sublingual + Lacrimal glands by its secretomotor fibers
Sensory Ganglion of Facial nerve called….. located in ……….
Geniculate ganglion
In intrapetrous part of facial nerve
Nuclei and fivers of facial nerve
MS2P
Motor facial nucleus of pons giving axons winding around the abucent nucleus formin the facial colliculus then go out through cerebellopontine anngle
Parasymp : From superior salivatory nucleus + lacrimal nuscleus
Fibers to nucelus solitarus from chorda tympani and greater petrosal
Fibers to Spinal nuscles of trigeminal for chonca
Explain COrtical control of facial motor nucleus
The dorsal part of facial nuscleus responsbile for upper facial muscles receives bilateral corticonuclear fibers so Lesion un UMNL don’t cause upper facial palsy
The ventral part of facial nucleus respobnisble for lower lower facial muscles receving only contralateral Corticonuclear fibers so lesion
in UMNL;
spared upper face+ contralateral lower face palsy
Exit of facial nerve from brain
From lower pons cerebello pontine angles fibers arragned FROM MEDIAL TO LATEARL
Motor root then Nervus intermedius
then the Vestibulo choclear nerve lateral to them
After exiting pons , facial nerve pass through ,,,,,,,,,,,, with ,,,,,,,,, + ,,,,,,,,,,,,,
IAM internal acoustic meatus with Vestibulochoclear + Larbynithial artery a branch of Basilar arterty for inner ear
if facial canal facial nerve runs laterally above ,,,,,, of ,,,,,,,…. / this part ends at ,,,,,,,,,,,
Then backwards in medial wall of ,,,,,,,,, above ,,,,,,,,,
then downwards descending vertcitally behind tympanic cavity down the ,,,,,,,, to exit skull
Vestibule of internal ear ending at Geniculate ganglion
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medial wall of tympanic cavity above Proomomtery
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Down the stylomastoid foramen to exist sklull
Extra cranial part of facial nerve begins after leaving ,……… giving 3 branches then enter the parotid ,,,,,, surface divding it into superfical and deep parts
Inside the parotid it forms a pleux called ……… then gives it 5 prominent Branches :Temporal zygomatic buccal mandibular cervical exiting parotid from ,,,,, surface ?
stylomastoid foramen
Posteromedial surface
Pes anserinus
anteromedial surface
Classify facial nerve branches
3 in petrous temporal bone
3 after leaving stlomastoid foramen
5 terminal branches from parotid
Mention branches of Facial nerve in petrous temporal bone
pts
1-Greater petrosal from geniculate ganglion
2-Chorda tympani
3-Nerve to Stapedius
Mention branches of facial nerve after leaving stylomastoid foramen
1- Post auricular
2- Muscular to posterior belly of digastric + stylohyoid muscle
5 terminal branches supply?
Temporal for orbiuclar oculi + frontalis
Zygomatic for orbiuclaris oculi
Buccal for buccinator
Mandibular for Lower lip
Cervical for ?Platysma
Greater petrosal nerve
fibers
Orgin ?
Course?
passes through its haitus in pertous temporal bone tor reach ,,,,,,,,,,,,, passing …….. trigemnial ganglion to the foramen,,,,,,,,
where it joins ,,,,,,, nerve to from ,,,,,,,,,
that relay in ,,,,, ganglion ?
Preganglioninc parasympathtatic fibers
taste fibers
Origin : geniculate ganglion
Course :
Middle cranail cavity
below tirgmenial ganglion to forament lacerum
where it joins deep petrosal nerve
to form
Nerve to pterygoid canal
Relay in pterygopalatine ganglion
Chorda tympani type of fibers
taste from ant 2/3 of tongue
Preganglionic parasympathatlic to submandiblar + sublingual salivary glands
Course of chorda tympani explain
Arise 6mm above stylomastoid forament then cross layers of tympanic membrane mallus and incus to ptereotympanic fissure to reach ?
InfraTemporal fossa to Joint Lingual Nerve!
To reach submanidbular ganglion
and taste for 2/3 tongue
What happens in case of suparnucler lesion of facial nerve
Contralateral lower side of face is affected
It is called UMNL
most common cause is Hemmhorage to internal capsule
What happens in case of nuclear & infranuclear lesion of facial nerve
Ipisilateral facial palsy
Called LMNL
Nuclear : Vascular accident of pons
Infranuclear : damage to nerve after emerging from pons
Exposure of face to cold can cause?
Bell’s palsy =
Ipislateral facial palsy
Test for Facial nerve
Eyebrows elevation for Frontalis
Closing eyes against resistane for Orbiuclaris oculi
Puff out the cheeks + reveal teeth for Buccniator
.إذا غامرت في شرف مروم ..
فلا تقنع بما دون النجوم
الحمدلله رب العالمين
Medial longitudian lbundle
Is fibers extending in brainstem paralle to Median plane ENding:
superiorly : Interstsisial nucelus of Cajal of post commisure
inferiorly : Medial Vestibulospinal Tract
What are the connections made by MLB?
Medial longitudinal bundle : - connects
Vestibular and choclear nuclei with :
1-Motor cranial nerves 3,4,6 and 3+6 with each other for ( lateral conjugate eye movements )
2-Spinal nucleus of trigeminal For Coordinated movemnt of eyeball + head in response to Vestobulochochlear stimuli
