Anatomy Exam 3/Lecture 5-Temporal region
Which nerve innervates the parotid gland 3,7, or 9?
9 - glossopharyngeal
What CN makes you smile and cry?
CN VII
How do the nerve fibers go from the Otic ganglion to the parotid gland?
Goes with the mandibular division(trigeminal) and postganglionic fibers join the auriculotemporal n which enters the parotid gland
What branches do you have coming from the maxillary artery after it branches from the external carotid artery which supply blood to the temporalis?
Deep temporal arteries providing blood supply to temporalis
What nerve supplies the temporalis which aides in mastication?
Deep temporal nerve - Mandibular division of Trigeminal
What are the anterior branches which are motor? Which nerve is the exception?
Deep temporal nerves - supply temporalis-MOTOR Masseter nerve- MOTOR Lateral pterygoid- MOTOR BUCCAL NERVE - SENSORY - looks like it will innervate buccinater but buccinater is muscle of facial expression which is innervated by facial nerve so this muscle should not be innervated by trigeminal, and it is not it actually penetrates the buccinater to supply the inside of your mouth and supply mucosa of mouth
Within the TMJ you have 2 joints, one is between the head of the mandible and the ________ and the other is between that and the _____________.
1 joint between head of mandible and fibrous disc/cartilage Other joint it between the disc/cartilage and the temporal bone
There are ____ muscles to open your mouth and _____ muscle(s) to close your mouth.
1 to open and 3 muscles to close your mouth.
Where do you find the Otic ganglion?
Medial side of mandibular division of trigeminal nerve
The remaining part of CN 8, 9, 10, 11,and 12 all come from what part of brain?
Medulla
Mandibular division of trigeminal nerve enters infratemoral fossa through foramen ovale, before its splits into anterior and posterior divisions it gives off what branch?
Meningeal branch
The main trunk of the facial nerve has a branch that extends inferiorly to supply what 2 muscles? At this point the facial nerve is purely motor.
Nerve to posterior belly of digastric muscle and stylohyoid muscle
CN 5, 6,7 and part of 8 come from what part?
Pons
What part of the brainstem is the facial nerve nucleus found?
Pons CN VII - facial
What are the 3 muscles responsible for closing your mouth?
Temporalis Masseter Medial Pterygoid
What muscle is attached to the coronoid process of mandible?
Temporalis - muscle of mastication - supplied by the mandibular division of trigeminal nerve
What are the 4 muscles of mastication?
Temporalis, masseter, medial pterygoid, lateral pterygoid
What ligaments protect the TMJ and do not allow your mandible to go too far down?
Temporomandibular ligament sphenomandibular ligament Stylomandibular ligaament
A patient has right Trigeminal nerve injury, which way will the jaw be pushed towards?
The right! If the right pterygoids are paralyzed due to a right trigeminal nerve injury, the remaining left muscles of mastication including the left pterygoids will push the jaw to the right.
What is the parasympathetic function of CN III oculomotor?
constricts your pupil, light accommodation reflex
Greater petrosal nerve + Deep petrosal nerve =
nerve of pterygoid canal
The infraorbital nerve will give off 3 branches what are they?
one to the lower eyelid(palprebral) one to the lateral part of the nose (Nasal) one to the upper lip (Labial)
How is the maxillary artery divided into 3 parts?
1st part is from its origin at the external carotid artery to the lateral pterygoid muscle 2nd part is where it runs on top of the muscle 3rd part is where it goes between the 2 heads of the pterygoids and enters the pterygopalatine fossa.
What 4 structures go through foramen ovale?
(MEAL) Mandibular division of Trigeminal nerve Emissary Vein Accessory middle meningeal artery Lesser petrosal nerve
This patient has an infection in the Pterygopalatine fossa, where will it spread???(it will not spread to this area of the head? if one of the options is middle ear - NO it will not spread there).
-Communicates laterally through pterygomaxillary fissure to infra temporal fossa. - Communicates medially through sphenopalatine foramen to Nasal Cavity -Communicates superiorly through inferior orbital fissure to Orbit -Communicates inferiorly through greater palatine canal to Palate -Communicates posteriorly to foramen rotundum to middle crania fossa
How many parasympathetic ganglia are there in the head? What are they?
4 -Cililary - 3rd nerve oculomotor light reflex -Otic - parotid gland through 9th nerve glossopharyngeal -Pterygopalatine- supply lacrimal gland and nasal - 7th nerve facial -Submandibular- submandibular and sublingual salivary gland - 7th nerve facial nerve
What nerves can be affected by a parotectomy that went wrong?
5,7,and 9
What is a combined joint?
A joint that is coupled with another joint and cannot move unless the other one moves as well
What is the Pterygopalatine fossa?
A small/narrow space inferior to the apex of the orbit and medial to infra temporal fossa and posterior to maxillary sinus
The mandible will move towards the _________ side in a trigeminal nerve injury.
AFFECTED
If you are above the zygomatic arch you are in the ________ region, if you are below the zygomatic arch you are in the ________ region.
Above - temporal region Below - PAROTID region
What is Freyes syndrome?
After parotidectomy the parasympathetic fibers within the auriculotemporal nerve(supplies skin) would try to regenerate and reach the skin of the temple. When the inferior salivatory nucleus is stimulated (when thinking about food ect.) the blood vessels in the temple will be dilated resulting in redness and sweating
What muscles would help in opening the jaw other than the lateral pterygoid?
All the supra hyoid muscles help to open jaw
What other muscles are innervated by the mandibular division of the trigeminal other that the 4 muscles of mastication?
Anterior belly of digastric Tensal tympani Tensal palantine Mylohyoid
What is a ganglion?
Any collection of nerve cell bodies that lie outside the CNS
What nerve supplies the TMJ and what kind of nerve is it? What kind of fibers run through it?
Auriculotemporal - Sensory and has parasympathetic fibers that run with it from the 9th Cranial nerve glossopharyngeal
What nerve supplies the TMJ temporomandibular joint?
Auriculotemporal n. - runs from beneath the TMJ supplying it and then going up over the temporalis muscle to supply the skin
What nerve originates in front of the ear and runs over the temporal is muscle? Is it sensory or motor?
Auriculotemporal nerve - nerve of the anterior portion of the scalp - Sensory
What are the posterior branches of mandibular nerve?
Auriculotemporal nerve -SENSORY Lingual nerve- SENSORY Inferior alveolar nerve - SENSORY to teeth of lower jaw Nerve to mylohyoid - innervates mylohyoid and anterior belly of digastric -MOTOR
Why is it impossible to dissect the parotid gland as a whole?
Because if you can transversely or vertically you will either cut the facial nerve and branches or the external carotid artery and retromandibular vein. This is why is must be dissected in pieces. Most commonly a small branch of the facial nerve being damaged is a complication.
If your parotid gland gets infected (acute parotiditis) and you have inflammation why is it so painful?
Because the parotid gland in encased in deep cervical facia which is inelastic and does not allow for stretch so when the parotid gland enlarges it presses on all those nerves surrounding it.
If someone has a fracture of petrostemporal bone what will happen to the facial nerve?
Bleeding through ear - facial paralysis on one side also loss of production of tears and saliva
What is the nerve of pterygoid canal?
Branch of facial nerve that supplies parasympathetic input
What is the whistling muscle or muscle you use to suck out of a straw?
Buccinator
Which cranial nerve supplies the parotid gland?
CN IX - glossopharyngeal
Where does the salivation signal start?
CN IX glossopharyngeal nerve starts in the medulla Starts when you see food you like, smell food, or even think about it.
What nerve coming from the back joins and runs with the lingual nerve?
Chorda tympani
A child has chronic Otitis media and is not eating anything, what is the connection?
Chorda tympani the nerve that supplies taste to anterior 2/3rds of tongue actually runs through the middle ear which can be affected by Otitis media and cause the child to loose taste.
If you see a patient that has full paralysis in one side of the face, what has occurred?
Damage to nerve - bells palsy
What is the action of the anterior half of temporalis?
Elevation on mandible
What connects the pterygoid plexus of veins to the cavernous sinus?
Emissary veins - which go through foramen Ovale
What clinical symptoms will you see in someone who has had a stroke in the left cortex?
Everything will be normal, wrinkles still present and can open/close eyes, however you will see the angle of their mouth is depressed in the right side and the corner of mouth only goes up in unaffected left side.
What 2 large vessels run through the parotid gland vertically?
External carotid artery and retromandibular vein
The anterior division of retromandibular veins joins with the ________ vein to form the common facial vein.
Facial
The _______ nerve enters the parotid gland and divides into 5 branches which are:
Facial nerve -Temporal -Zygomatic - Buccal - Mandibular - Cervical
how does the facial nerve control the lacrimal gland?
Facial nerve has a geniculate ganglion from which arises the greater petrosal nerve which joins with deep petrosal nerve to form the nerve of pterygoid canal (vidyans nerve) which ends in the pterygopalatine ganglion from which branches arise and run through the maxillary division of trigeminal nerve to supply lacrimal gland
The masseter, temporalis, and medial pterygoid all do what action? What does the lateral pterygoid do?
First 3 all elevate mandible and help close jaw. The Lateral pterygoid helps protude mandible or Open the mouth. ALL are innervated by the mandibular division of trigeminal (V)
What are the 3 foramen present in the greater wing of sphenoid which is roof of infra temporal fossa?
Foramen Ovale, Foramen Spinosum, and Foramen Rotundrum
Which foramen does the middle meningeal artery run through?
Foramen Spinosum
What foramen do you expect to see in the roof of the Pterygopalatine fossa ( which is greater wing of sphenoid bone)?
Foramen rotendum
Where does the tympanic nerve of glossopharyngeal travel and what does it form?
Forms a tympanic plexus of nerves in middle ear and gives off the lesser petrosal nerve
Cranial nerves 3-12 nuclei are found where?
In brainstem
Where are the parasympathetic and sensory branches of the facial nerve given off?
In the facial canal before it leaves through the stylomastoid foramen and becomes purely motor.
The maxillary artery is going to give off 16 branches. The branch that run through the mandible is what branch?
Inferior Alveolar Artery - blood supply to teeth of lower jaw
What nerve would you block if you were doing a procedure in the lower jaw? Why might sometimes you end up with a numb tongue as well?
Inferior alveolar nerve - can hit the lingual nerve by accident since it lies right next to the inferior alveolar nerve
What does the Pterygopalatine fossa communicate with laterally?
Infratemporal fossa through pterygomaxillary fissure
Where does the facial nerve enter in the skull with the 8th CN?
Internal acoustic meatus
The common facial vein drains into what larger vein?
Internal jugular vein
Any infection in infratemporal fossa can easily spread where, what lobe of brain? why?
Into the intracranial space above and to the temporal lobe of brain through the 2 openings foramen ovale and spinosum.
What are the characteristics of the TMJ, why is it complex?
It is a combined joint, a synovial joint, it is complex because there is a fibrous disc within the joint cavity. It is called a simple joint because it involves only 2 bones.(if there are more than 2 bones in a joint it is called compound)
What do we know about lesser petrosal nerve?
It is the parasympathetic branch that comes from the tympanic plexus which is within the middle ear that carries the parasympathetic fibers from glossopharyngeal CN IX it goes through foramen oval to reach otic ganglion jumps onto auriculotemporal nerve to reach parotid gland.
How can you identify the Auriculotemporal nerve?
It will have 2 roots that will join to form it with the middle meningeal artery running through the 2 rootlets
What happens if the lingual nerve is cut BEFORE the chorda tympani nerve joins it?
Just loss of general sensation, patient still can taste and has salivary production
Excessive contraction of which muscle can cause the heads of the mandible to dislocate past the articular tubercles?
LATERAL PTERYGOIDS
What is responsible for pulling the articular disk forwards?
Lateral Pterygoid muscle - helps to fully open your mouth pulling the head of mandible forwards
What are the contents of the Infratemporal Fossa?
Lateral and medial pterygoid muscles Small part of temporalis Maxillary artery Pterygoid venous plexus Branches of CN V3 Chordae tympani Otic ganglion
Right pterygoids make your mandible go the the _____ side. Vice Versa
Left
What nerve comes from the middle ear and joins the Otic ganglion?
Lesser petrosal nerve (Chorda tympani also comes from middle ear and merges with the lingual nerve)
If you are asked to identify the middle meningeal artery what is a good landmark to look for?
Look for an artery that goes between 2 nerves where they split which is auriculotemporal nerve.
How can you test the 9th cranial nerve if someone comes in why chronic dry mouth from lack of saliva production?
Look for gag reflex, lack of gag reflex = problem with IX glossopharyngeal
What happens if chorda tympani is cut?
Loss of taste in the anterior 2/3rds of the tongue in that side where it was cut and loss of salivary production from those 2 glands
By the time the facial nerve comes out of the stylomastoid foramen it is purely a ______ nerve.
MOTOR
If there is a muscle which is being innervted by the Trigeminal nerve it has to be the ________ division because it is the only one that is has a motor component.
Mandibular
Nerve to mylohyoid is a branch of ?
Mandibular - trigeminal
What nerve innervates the temporalis muscle and what is its purpose?
Mandibular division of Trigeminal nerve (V) - Mastication
What is the deep temporal nerve which innervates the temporalis a branch of?
Mandibular division of trigeminal
Which division of trigeminal is innervating the anterior belly of digastric muscle?
Mandibular division of trigeminal
In the TMJ where does the head of the mandible articulate?
Mandibular fossa of temporal bone
What 3 structures form the TMJ?
Mandibular fossa of temporal bone Articular Tubercle (of temporal bone) Condylar process/ head of mandible
CN 3 and 4 come from what part of the brain?
Midbrain
What branch of the maxillary artery is going to go through the foramen spinosum as well as being surrounded by the 2 nerve rootlets of auriculotemporal nerve.
Middle Meningeal artery- goes through spinosum and into epidural space
What other artery is present deep to the pterion as well as the middle meningeal artery that can be damaged if struck in this area?
Middle cerebral artery
What could lead to loss of taste to anterior 2/3rds of tongue?
Middle ear infections - since chorda tympani comes from middle ear
What goes through foramen spinosum?
Middle meningeal artery
Exactly deep to the Pterion there is an important blood vessel which is ? Why is this fatal if struck?
Middle meningeal artery (located in the dura) If you have a blow to the Pterion area it can rupture this middle meningeal artery and cause an epidural hematoma which would put pressure on the brain and end up pushing down the brainstem.
The anterior division of the mandibular nerve is mainly ______ and one ______ nerve.
Motor and 1 sensory
Epidemic parotitis is also know as ______.
Mumps
If someone has a stroke within the internal capsule of the right side, will the left upper side be affected?
NO because the left upper face also receives corticonuclear tracts from the left side.
After the lesser petrosal nerve arises from the tympanic plexus from the glossopharyngeal nerve it goes through the foramen ovale and enters what ganglion?
Otic ganglion
The mandibular nerve (branch of trigeminal) enters the infratemporal fossa through foramen _______, and gives anterior and posterior branches.
Ovale
If someone has a stroke on the left side cortex what will you see in the face?
Paralysis in Lower RIGHT side
What would you see in a patient if the anterior division of the mandibular nerve (branch of trigeminal) on the right side was accidentally cut during surgery?
Paralyze muscles of mastication Mouth will go the the right because the left medial and lateral pterygoids would push jaw to opposite side.
All glands in the body are innervated by _________ nerves, except the sweat glands.
Parasympathetic (sympathetic NS will shut off all the glands except sweat glands - when you are extremely nervous you sweat and cannot swallow)
The ______ duct runs anteriorly from the parotid gland crosses over masseter muscle and pierces the ____________ to enter the vestibule located opposite the 2nd molar.
Parotid (stensons) , buccinator
80% of the saliva we make comes from the ______ gland.
Parotid - largest salivary gland - serous
What branches off the main trunk of the facial nerve to supply the occipitalis?
Posterior Auricular n.
The retromandibular vein divides into an anterior and posterior vein. The posterior division of the retromandibular vein joins with what vein to form the external jugular vein?
Posterior auricular vein
Infants have 6 fontanels that becomes specific regions where the bones meet as they mature. The 2 anteriolateral fontanels in an infant become what structure?
Pterion
The floor of the temporal region/fossa is made up of 4 bones (H shaped) which form the ________.
Pterion (frontal, parietal, temporal and greater wing of sphenoid)
The facial nerve supplies what 2 parasympathetic gangia, what are they?
Pterygopalatine (lacrimal and nasal gland) and submandibular
What is the action of the posterior half of temporalis?
Retraction of mandible
Maxillary vein and superficial temporal vein join to form what larger vein?
Retromandibular vein
What are the boundaries of Pterygopalatine fossa?
Roof - greater wing of sphenoid Medial wall - vertical plate of palatine bone Floor- pyramidal process of palatine bone Anterior -Posterior surface of maxilla Posterior - pterygoid process of sphenoid
What is cancer of a connective tissue origin?
Sarcoma
The posterior branch of mandibular nerve is mainly ______ besides one branch which is ______.
Sensory and only 1 Motor (opposite of anterior division)
What are boundaries of the Infratemporal Fossa?
Space behind maxilla and below temporal region. Superior - Greater wing of sphenoid Medially- lateral pterygoid plate of sphenoid Laterally - Ramus of mandible Anteriorly - Posterior Maxilla Inferior- near angle of mandible
The Pterygopalatine fossa is also known as ______________.
Sphenopalatine fossa - Pterygoid plates are part of the bone sphenoid
What is the parasympathetic function of CN VII?
Stimunates the lacrimal gland
What foramen does the main trunk of the facial nerve emerge from?
Stylomastoid foramen
In the temporal region you can see the external carotid artery giving off what 2 terminal branches?
Superficial temporal (runs on top of the temporalis) and maxillary artery which is going deep
What artery and vein are on top of the temporalis?
Superficial temporal artery and vein
The teeth of the upper jaw are supplied by another branch of the maxillary artery called what?
Superior Alveolar Artery
What are the boundaries of the parotid gland?
Superiorly - zygomatic arch Posteriorly - mastoid process/external ear Medially - ramus of mandible Anteriorly - masseter muscle Inferiorly - angle of mandible
What are the boundaries of the temporal region?
Superiorly and posteriorly- temporal lines Anteriorly - frontal bone and zygomatic bone Inferiorly - zygomatic process(zygomatic process of temporal bone)
What type of joint is TMJ temporomandibular joint?
Synovial joint - there is a gap in between 2 bones filled with fluid - freely movable (has a capsule to contain the fluid
What goes through foramen rotendum?
The Maxillary division of Trigeminal nerve
What creates a capsule for the parotid gland?
The investing layer of deep cervical facia (same one that covers the trapezius goes up and attaches to the zygomatic bone) - forms the parotid sheath.
The nucleus for facial nerve is split into 2 halves, the nucleus for upper face and nucleus for lower face. How do they differ?
The nucleus for upper face receives corticonuclear tracts from BOTH sides, whereas the nucleus for the lower face only receives corticonuclear tracts from the OPPOSITE side.
You have a patient that has chronic middle ear infection and also has trouble producing saliva, what is the connection?
The tympanic plexus is within the middle ear, it is from this plexus that the lesser petrosal nerve arises and reaches the parotid gland
If a patient can bring their bottom set of teeth more anterior to their top set of teeth what does this tell you?
Their pterygoids are good
What happens if the lingual nerve is cut after the chorda tympani nerve joins it?
There will be loss of general sensations (touch, pain, temperature) as well as Taste and parasympathetic input to submandibular and sublingual glands.
Facial nerve, there are fibers going to lacrimal gland, fibers going to salivary gland, fibers supplying muscles of the face and sensory fibers for taste. What can happen after a fracture to the petrosotemporal bone when the facial nerves start to regenerate?
They can get switched and fibers that are suppose to go the the lacrimal gland will go to salivary gland and vice versa = you see food/ smell food you start crying. This is called crocodile tear syndrome. Damage was within the petrostemporal bone - in outward part.
How does the Pterygopalatine fossa region communicate with the Middle cranial fossa which is posterior to it?
Through foramen rotundem
What happens when both the left lateral and medial pterygoids contract? Which way do they pull the mandible?
Towards the RIGHT side (deviate the mandible in the opposite direction) When the right and left side contract at the same time you will have side to side movement.
How can an infection in the infra temporal fossa travel to the cavernous sinus and cause thrombosis?
Travel up through foramen ovale by emissary veins
Which of the cranial nerves are not formed in the parotid gland? CN 5 CN 7 CN 9 CN 10
We see 5 going through the gland - trigeminal We see 7 going through the gland - Facial We see 9(glossopharyngeal) going with 5(trigeminal) through the gland NOT CN 10
Why do we get a headache?
When an artery pulsates in the brain or epidural space it stretches the duramater which is very sensitive (pulsate headache)
Where is the geniculate ganglion?
Where the facial nerve makes a "bend" back within the facial canal
If someone has a stroke within the internal capsule of the right side cortex, will the lower left side of face be affected?
YES because the lower face receives its input only from the opposite side
The maxillary nerve passes through the foramen rotundum into pterygopalatine fossa, gives off ganglionic branches to the pterygopalatine ganglion through infraorbital fissure where it becomes ___________ nerve and then exits infraorbital foramen to supply face with ________ innervation.
infraorbital , sensory
The lateral and medial pterygoids are deep to the masseter and are both _______ to the joint (TMJ).
medial
What is the chorda tympani nerve?
sensory and parasympathetic branch of facial nerve (which enters lingual nerve) which carries taste from anterior 2/3rds of the tongue and innervates submandibular and sublingual salivary glands
The hypothalamus give signal to medulla to the inferior salivary nucleus and that gives off a nerve called ?
tympanic nerve
