Facial nerve+ MLB +V.O.T pathways Flashcards
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
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
Receptors of Vestibular pathway are ?
Macula of saccule + utricle
Crista ampullaris in semicircular canals
_____________________________________________Sending to Vestibular gnaglion giving vestibular nerve emerging from internal acoustic meatus with facial nerve then enter posterior cranial fossa then in Cerebellopontine angle reaching Brain stem
then to Vestibular nuclei :
1-Vestibluocerebellar to fluuclondoular node
2-Vestibulospinal for motor neurons for posture and balance
3-Connected to MLB To nuclei of 3,4,6 cranial nerves and spinal nuscleus of trigmental for regulated head movemnt + Conjugate eye movement
4-Thalamus to corticoVestibular area
Vestibular path :-
Receptors = .,…….+……..
sending to …..ganglion giving …..nerve
emerging from ………. with ……. then enter …..fossa then to cerebellopontine angle reaching brain stem then to ,,,,,nuclei
giving fibers :
…………TO flucclondilar node
……………….to motor neurons for posture and balance
connected to MLB conencting it to …….and…and…and……
Thalmamus to………….
Macula + Crista Ampullaris
Vestibular - Vestibular
Internal acoustic meatus with facial nerve
enter posterior cranial fossa
Vestivular nuclei
1-Vestiblo cereebellar
2-Vestiublospinal
3- occlumotor , trochlare- abucent nucei and spinal nucelis of trigmenial
4- to CorticoVestibular area
Describe Vestibular cortical area
Lies in the superior temporal gyrus near primary auditory area
Receving infromation about Head postition and movments from vestibular nuclei after realyin on VPMN of thalamus
Lesion of Vestibular nerve leads to ?
Diseqilibrium + vertigo
Tinnits + deafness + vertigo + Facial palsy occurs in case of ?
Cerebellopontine angle compression
Swhannomma of the neruilemmal sheath of Vestibulochoclear nerve
Causing compression of facial nerve + Vestibulochoclear nerve
Mention components of olfactory pathway
Olfactory epithelium receptors
Oflactory nerve
Olfactory bULB
Olfactory Tract
Olfactyory stria
Olfacroty cortex
Mention components of olfactory pathway
Olfactory epithelium receptors
Oflactory nerve
Olfactory bULB
Olfactory Tract
Olfactyory stria
Olfacroty cortex
Mention components of olfactory pathway
Olfactory epithelium receptors
Oflactory nerve
Olfactory bULB
Olfactory Tract
Olfactyory stria
Olfacroty cortex
Olfactory epithelium Describe + olfacroty nerves
Lining of ciribifrom pate of ehthmoid or roof of nose
Has the Peripheral process of the receptor cells Bipolar nerves
for receving sensations
Developed from surface ectoderm not neuroectoderm
Turnover = 3months
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Olfactory nerve: Formed of central process of Bipolar neurons Traversing ciribriform of ethomid to end in oflcatory bulb
Desscribe olfactory bulb
= lies in the Orbital sulcus in the Orbital surface of frontal lobe where olfactory nerves run
Synapsing with ( Mitral + Tufted) cells
Whose axons run in Olfactory Tract
Olfactory tract widens in the anterior apsec of ,,,,,,,, ending in ,,,,,,,,,,,
Anterior Perforated substance
___________
three olfcatory stria
Which stria ends in Primary olfactory cortex ?
Lateral olfactory stria
Which stria ends in Primary olfactory cortex ?
Lateral olfactory stria it is the most important
Medial olfactory stria terminates in ?
App
Paraterminal gyrus
paraolfactory gyrus
Anterior Commisure
Parts of septal area involved in olfcatory path ?
2P
Paraterminal + ParaOlfactory gyrus
Linking Olfaction + limbic system =
Anterior commisure of Medial stria
Ending in olfactory tubrcle ( a small tubercle in anterior Perforated substance )
Intermediate Olfactory stria
Mention parts of Primary olfactory cortex
I and U
-Insula apex
-Amygdala part
-Uncus
_________
Recviving from Lateral Olfactory stria giving ? ? 2nd Olfactory cortex
Enthorinal area repesnts ……… cortex
Reciving from ……
it lies in ,…….
2ry olfacrotry cortex
1ry one
Anterior part of parahippocamap gyrus
Unilatearl ansomia due to ?
Bilateral due to ?
Unilateral : Frontal lobe tunor
Bilateral : Fracute of Ciribrifrom plate of ethomid
Or cold and Rhinitis
Both Amygdala and Septal areas are connected to ?
Hypothala,us
Why smell can cause autonomic effects ?
This is due to connection between amydala and septal areas which represents areas of olfactory cortex to Hypothalamus in which autonoic centers exist
So smell induces Visceral Respneses as Salivation to pleasnet smell
and Vomiting +nausea to offensive one
Receptors of taste found in ..?
Turnover= ?
Tongue + Epiglottis + Soft palate
Turnover =10 days
Taste senastion is carried by 3 Cranial nervces explain
1-Facial nerve ant 2/3 of tongue
2-Glossopharyngeal post 1/3 of tongue
3-Vagus = most posterior tongue + Epiglottis
Describe taste pathway
Impulses from receptors to first ordere neurons:-
-Facial nerve fibers from ant 2/3 of tongue
-Glossopharyngeal from post 1/3 of tongue
-Vague from most posterior tongue + Epiglottis
to Nucelus soliratus then
2nd order neruons begin to forming Solitariothalamic Tract to reach Thalamus VPMN then
3rd Order Neuron Reaches the insula from VPMN
Smell and taste are functionally InterRelated show >
Hi3
Both are related to food intake=-=
Both terminates in ipsilateral cortex
Both integrated in insula + Oribtofrontal gyrus
Both affects hypothalamus Autonomic centers
Smell and taste are functionally InterRelated show >
Both are related to……………=-=
Both terminates in …………….
Both integrated in ………. + …………..
Both affects ………….
Smell and taste are functionally InterRelated show >
Both are related to food intake=-=
Both terminates in ipsilateral cortex
Both integrated in insula + Oribtofrontal gyrus
Both affects hypothalamus Autonomic centers
فلا هزيمةَ فيها ولا يأس
… فرصة تتلوها الفرصة
فاغتنم الخبرة….
. ولا تيأس
“الحمدلله رب العالمين “
.
