Anatomy [Week 2] Flashcards
What are the 3 CT layers of the meninges?
dura mater, arachnoid mater, pia mater
Where does the majority of venous blood flow in the brain?
dural venous sinuses (into the IJV)
What filters blood plasma to form CSF? Where is it located?
CHOROID PLEXUS; lining walls of all 4 VENTRICLES {flows out of 4th ventricle via apertures)
Where does CSF go from the APERTURES of the 4th VENTRICLE?
out of the median/lateral apertures into SUBARACHNOID SPACE between the arachnoid mater and pia mater
How does CSF get from the SUBARACHNOID MATER back into the VENOUS SINUSES?
via the ARACHNOID VILLI and capillary absorption
What composes the DURA MATER?
PERIOSTEAL and MENINGEAL layers
Where are the 2 layers of the DURA MATER separate?
inseparably bound through most of internal lining but separate at some locations to for DURAL SEPTAE and DURAL VENOUS SINUSES
To what is the PERIOSTEAL layer of the brain attached?
internal surface of the skull via SHARPEY FIBERS; strongly anchored to sutures
What is the MENINGEAL LAYER of dura mater? What special structures does it line?
continuous with dura mater lining internal surface of vertebral canal; envelopes CRANIAL NERVES
What are the DURAL SEPTAE?
folds of MENINGEAL LAYER of dural mater that restrict movement of brain within cranial vault
What is the FALX CEREBRI and where is it located?
layer of MENINGEAL dural mater vertically within longitudinal cerebral fissure; attaches to CRISTA GALLI anteriorly and to TENTORIUM CEREBELLI posteriorly
What is the TENTORIUM CEREBELLI and where is it located?
courses horizontally between PETROUS parts of temporal bone and internal lining of OCCIPITAL bone; separates occipital loves of cerebrum from cerebellum
What does the TENTORIUM CEREBELLI enclose?
TRANSVERSE and SUPERIOR PETROSAL sinuses
What is the DIAPHRAGMA SELLAE?
horizontal hood of DURA MATER that covers the PITUITARY GLAND over the SELLA TURCICA
What is the EPIDURAL SPACE?
potential space between CRANIUM and PERIOSTEAL LAYER of dura mater
When does an EPIDURAL SPACE appear?
pathology; ex. blood hemorrhaging from torn MIDDLE MENINGEAL ARTERY that separates dural mater from skull
Where does the PERIOSTEAL LAYER of the dura mater end and what does that mean for the EPIDURAL SPACE?
it ends at the FORAMEN MAGNUM, which means that it is separate from spinal epidural space
What is SUBDURAL SPACE?
not a natural space; seen during pathology-ex. rupture of cerebral-bridging vein where blood separates dura and arachnoid mater interface
What space is seen when there is a rupture of the CEREBRAL-BRIDGING VEIN?
SUBDURAL SPACE (between dura and arachnoid maters)
What is the LEPTOMENINGES and what is contained in in?
aka SUBARACHNOID SPACE; contains CSF, thin, CELLULAR TRABECULAE of arachnoid mater and many CEREBRAL VESSELS
Which type of cells and cell junctions primarily make up the ARACHNOID MATER?
squamous and cuboidal cells, desmosome cell junctions
What are ARACHNOID VILLI (granulations) and where are they located?
highly folded arachnoid mater projecting into the superior sagittal sinus (often produce indentations in inner surface of calvaria)
What is the purpose of ARACHNOID VILLI?
they are sites where CSF diffuses into blood of SUPERIOR SAGITTAL SINUS
What is the PIA MATER and where is it located?
a 1-2 cell thick layer following the traversing brain and covering blood vessels as they course into the fissures and sulci
What is the relationship to the PIA MATER and CHOROID PLEXUS?
pia mater joins with EPENDYMAL CELLS that line ventricles of brain to form choroid plexus
What is the function of the PIA MATER?
to protect brain and serve as an essential regulatory layer between the subarachnoid space and brain
What does the VENTRICULAR SYSTEM OF THE BRAIN consist of?
2 paired lateral ventricles, and a 3RD and 4TH midline ventricle connected via the CEREBRAL AQUEDUCT; 4th ventricle continuous with central canal of spinal cord
What is the CEREBRAL AQUEDUCT?
connected the 3RD and 4TH VENTRICLES; allows movement of CSF between them
What do the LATERAL VENTRICLES communicate with? Through which opening?
with the 3RD VENTRICLE via the INTERVENTRICULAR FORAMEN
Where is the 3RD VENTRICLE located?
space between the right and left halves of the DIENCEPHALON
What is the 4TH VENTRICLE and where is it located?
diamond-shaped fossa posterior to PONS and MEDULLA and anterior to CEREBELLUM; tapers infeciorly into narrow channel that continues inferiorly as the CENTRAL CANAL
What is CSF composed of and where does it come from?
clear, watery fluid with some electrolytes/protein that arises as ultrafiltrate and secretory product of CHOROID PLUSES of ventricles; receives minor contributions from capillaries in brain and EPENDYMAL lining of ventricles
What is the CEREBRAL AQUEDUCT OF SYLVIUS?
narrow channel within MIDBRAIN that connects 3RD/4TH VENTRICLES; DOES NOT CONTAIN CHOROID PLEXUS
Does the CEREBRAL AQUEDUCT contain choroid plexus?
NO!!!!!
What do the cells of the CHOROID PLEXUS serve as?
a blood-CSF barrier (BBB)
What is the volume of the CSF within VENTRICLES and SUBARACHNOID SPACE?
about 125-150 mL
Of the CSF in ventricles/subarachnoid space, how much is intracranial and how much in spinal cord?
intracranial=125 mL; 25 mL in ventricles and 100 in subarachnoid space
spinal cord=25 mL
What is the function of CSF?
to provide a hydraulic cushion to buoy and protect brain and spinal cord within bony encasements; also prevents weight of brain from compressing CRANIAL NERVES and blood vessels
Describe the circulation of CSF from the CHOROID PLEXUS to the SUBARACHNOID SPACE.
about 450 mL/day CSF produced from choroid plexus–>leaves lateral ventricles, down intraventricular foramen to 3rd ventricle then through cerebral aqueduct to 4th ventricle–>CSF enters subarachnoid space via:
(1) MEDIAN APERTURE OF MAGENDIE
(2) LATERAL APERTURE OF LUSCHKA
What is the MEDIAN APERTURE OF MAGENDIE?
UNPAIRED opening that drains CSF from 4th ventricle into CISTERNA MAGNA of subarachnoid space
What is the CISTERNA MAGNA?
type of subarachnoid space; posterior to pons and anterior to cerebellum; MEDIAN APERTURE drains to here
What is the LATERAL APERTURE OF LUSCHKA?
PAIRED openings that drain CSF from 4th ventricle into CEREBELLOPONTINE ANGLE CISTERN of subarachnoid space
What is the CEREBELLOPONTINE ANGLE CISTERN?
type of subarachnoid space; LATERAL APERTURE of 4th ventricle drains here
Why can increased CSF volume result in vision deficit?
CSF surrounds CRANIAL NERVES as it exits the 4th ventricle into the subarachnoid space; the optic nerve, CN II, is particularly vulnerable
How is CSF ultimately absorbed back into systemic blood stream?
via MENINGEAL CAPILLARIES, EXTRACRANIAL LYMPHATICS and ARACHNOID VILLI
From which 3 arteries do the DURA MATER and overlying SKULL BONES receive their arterial supply?
ANTERIOR MENINGEAL ARTERY (AMA)
MIDDLE MENINGEAL ARTERY (MMA)
POSTERIOR MENINGEAL ARTERY (PMA)
From where does the ANTERIOR MENINGEAL ARTERY originate and what does it supply?
originates from the ANTERIOR and POSTERIOR ETHMOIDAL ARTERIES; supplies DURA MATER in anterior cranial fossa
From where does the MIDDLE MENINGEAL ARTERY ORIGINATE and what does it supply?
originates from the MAXILLARY ARTERY (infratemporal fossa) and traverses the FORAMEN SPINOSUM and courses along the SQUAMOUS part of temporal bone–>bifurcates into FRONTAL and PARIETAL branches; supplies dura mater and overlying skull
What is an important relationship between the MMA and AURICULOTEMPORAL NERVE?
auriculotemporal nerve SPLITS and courses around both sides of the MMA prior to joining together again adjacent to TEMPOROMANDIBULAR joint
From where does the POSTERIOR MENINGEAL ARTERY ORIGINATE and what does it supply?
PMA originates from OCCIPITAL ARTERY and supplies dura mater in POSTERIOR cranial fossa
Where are the DURAL VENOUS SINUSES located?
between periosteal and meningeal layers of dura mater
What are a few characteristics of the DURAL VENOUS SINUSES?
lined with endothelium, LACK VALVES, serve as vessels for blood from the cerebral veins, diploic veins and emissary veins, receive CSF drained by arachnoid granulations
Where does the blood from the DURAL VENOUS SINUSES primarily drain? How about secondarily? Why?
primary=INTERNAL JUGULAR VEINS
secondarily=SUPERIOR OPHTHALMIC VEINS or PTERYGOMAXILLARY PLEXUS (because no valves)
Where does the SUPERIOR SAGITTAL SINUS course?
from FALX CEREBRI at FORAMEN CECUM where it communicates with nasal cavity [*danger triangle]; courses along superior border and drains into confluence of sinuses where deviates to RIGHT side (usually) as TRANSVERSE SINUS
What is the course of BRIDGING VEINS?
from brain, pierce ARACHNOID and DURA maters and drain directly into SUPERIOR SAGITTAL SINUS
What is the course of the INFERIOR SAGITTAL SINUS?
in midline along inferior forder of FALX CEREBRI along CORPUS CALLOSUM; receives veins from medial surface of cerebrum and joins with GREAT CEREBRAL VEIN OF GALEN to form STRAIGHT SINUS
What is the course of the STRAIGHT SINUS?
along line of attachment of FLAX CEREBRI to TENTORIUM CEREBELLI; continuation of INFERIOR SAGITTAL SINUS and drains into TRANSVERSE SINUS
What is the course of the OCCIPITAL SINUS?
within FLAX CEREBELLI from confluence of sinuses and terminates at FORAMEN MAGNUM with the INTERNAL VERTEBRAL VENOUS PLEXUS (smallest of dural venous sinuses)
What is the CONFLUENCE OF SINUSES?
the union of: -SUPERIOR SAGITTAL SINUS -STRAIGHT SINUS -OCCIPITAL SINUS at internal occipital protuberance
What is the course of the TRANSVERSE SINUS?
laterally from CONFLUENCE OF SINUSES within tentorium cerebelli inferiorly as SIGMOID SINUS; receives INFERIOR CEREBRAL and INFERIOR CEREBELLAR VEINS
Why is the RIGHT transverse sinus usually larger than the left?
because it is a continuation of the SUPERIOR SAGITTAL SINUS!
What is the course of the SIGMOID SINUS?
continuation of TRANSVERSE SINUS; descending S-shaped groove; unites with SUPERIOR PETROSAL SINUS at the JUGULAR FORAMEN to form the IJV
Where is the CAVERNOUS SINUS located?
on each side of the SELLA TURCICA, extending from the superior orbital fissure to the petrous part of temporal bone
What courses through the middle of the CAVERNOUS SINUS? What courses anteriorly through its lateral walls?
in middle= INTERNAL CAROTID ARTERY and CN VI
anteriorly=CN III, CN IV, CN VI, CN V2
How does the CAVERNOUS SINUS communicate with the PTERYGOID VENOUS PLEXUS?
via EMISSARY VEINS and SUPERIOR/INFERIOR OPTHALMIC VEINS (in orbit)
How does the CAVERNOUS SINUS communicate with the TRANSVERSE SINUS?
via SUPERIOR PETROSAL SINUS
How does the CAVERNOUS SINUS communicate with the INTERNAL JUGULAR VEIN?
via SUPERIOR/INFERIOR PETROSAL SINUS
What is the course of the SUPERIOR PETROSAL SINUS?
along superior portion of PETROUS part of temporal bone from CAVERNOUS SINUS to TRANSVERSE SINUS
What is the course of the INFERIOR PETROSAL SINUS?
along inferior portion of PETROUS part of temporal bone from CAVERNOUS SINUS to IJV
What is the SPHENOPARIETAL SINUS?
variable sinus that is more likely combination of sinus of LESSER WING of sphenoid bone and MIDDLE MENINGEAL VEIN; joins CAVERNOUS SINUS
What is the course of DIPLOIC VEINS?
within SPONGY portion of cranial bones and drain into most of DURAL VENOUS SINIUSES
What is the course of EMISSARY VEINS?
EXTRACRANIALLY from scalp into DURAL VENOUS SINUSES intracranially
Describe LYMPHATICS in the context of the brain and spinal cord.
lymphatic vessels DO NOT EXIST within parenchyma of brain/spinal cord
What gives the DURA MATER general SENSORY and SYMPATHETIC INNERVATION (to blood vessel smooth muscle)?
MENINGEAL BRANCHES of 3 divisions of CN V and C2-C3 spinal nerves
Where is pain from the dura mater usually referred? What nerves are responsible for this?
to the head; it is perceived as a headache; from mucosal regions supplied by CN V or C2-C3 dermatomes
How is GRAY and WHITE matter arranged in the spinal cord?
gray=inside
white=outside
A patient comes to the ER after getting hit in the side of the head with a softball during an intramural game. He passed out at the scene then regained consciousness, so his teammates thought he was okay. Later, however, he lost consciousness again. In the ER you notice swelling of the patient’s head that stops abruptly as a “lensticular” shape. What would be in your differential diagnosis and what structures would be involved? What is the worst outcome anatomically?
- the ball probably hit the PTERION SUTURE, causing a fracture and laceration of the FRONTAL, MIDDLE MENINGEAL ARTERY, leading to an EPIDURAL HEMATOMA (separation of peritoneal layer of dura mater from skull bone); “lensticular” shape is due to dura mater’s strong attachment to cranial sutures, limiting spread of blood
- worst outcome would be that the brain is compressed down through the FORAMEN MAGNUM
A patient comes to the ER after a car accident during which the patient had to slam on her breaks. In the ER you notice amorphous swelling of the patient’s head. What would be in your differential diagnosis and what structures would be involved?
because the dura matter and arachnoid mater is connected tightly to the skull, the sudden stop would cause the brain to move within its casing, causing sheering of the BRIDGING VEINS (in the SUBARACHNOID SPACE) leading to a SUBARACHNOID HEMATOMA
A patient comes to the ER because he has a terrible headache. He tells the doctor he was playing a drinking game to The Dark Knight where he took a shot every time Christian Bale did his Batman voice. What is the physiological cause of this headache?
alcohol causes you to become dehydrated (it is a diuretic) and so your CSF volume decreases, causing the bath of CSF fluid around the brain to decrease, stimulating CN V sensory nerves due to mechanical forces on the brain (it isn’t suspended anymore)
What groove runs along the anterior portion of the TENTORIUM CEREBELLI attachment?
SUPERIOR PETROSAL groove (contains the venous sinus)
Which 2 canals are part of the JUGULAR FORAMEN and which structures go through the each?
VASCULAR canal=INTERIOR JUGULAR FORAMEN
NERVOUS canal=CN IX, X, XI
What is the path of venous drainage when standing up?
- superior sagittal sinus and confluence of sinuses drain into…
- transverse sinus which drain into…
- [superior transverse sinus and] sigmoid sinus which drains into..
- IJV which track through…
- JUGULAR CANAL
Where does the PTERYGOID VENOUS PLEXUS drain?
directly to CAVERNOUS SINUS
You need to do an emergency procedure to put in a CENTRAL VENOUS CATHETER. Which side and through which structure should you put the catheter?
through the IJV on the RIGHT side by finding SCM and inserting the needle between the insertion of the clavicle and sternum; RIGHT because IJV meets subclavian and goes all the way across the midline on the left side before it dumps into the RIGHT ATRIUM (so would need longer catheter on left side)
What are the tributaries to the DANGER ZONE OF THE FACE?
- ANGULAR (supraorbital=sup/inf. ophthalmic v.; supratrochlear, external nasal)*
- SUPERIOR LABIAL*
- DEEP FACIAL*
- INFERIOR LABIAL*
- TONSILLAR
- SUBMENTAL
- SUBMANDIBULAR
- exposed to surface of face
Why is the DANGER ZONE OF THE FACE dangerous?
a clotting cascade from infection or the infection itself have direct access to the CAVERNOUS SINUS, and therefore to the brain
A teenager picked a pimple two days ago on his nose and now he cannot look laterally (eye stuck medially) with his left eye and he has double vision. What happened and which nerve is affected?
the angular vessels of CN VII drain directly into cavernous sinus which, when an infection gets in, can swell and affect CN VI (innervating the LATERAL RECTUS MUSCLE of the eye)
Which nerves are close in proximity to the CAVERNOUS SINUS? Which is the closest?
- CN III, CN IV, CN V (1 &2), CN VI
- CN VI is the closest
A patient has a cavernous sinus THROMBOSIS. Which nerve is most likely to be affected and how will the patient present?
CN VI (abducens); lateral rectus muscle not working–>eye pointed in medially and patient would have double vision due to venous swelling
A patient has a stabbing pain on the bridge of his nose. Which nerve is the CAVERNOUS SINUS THROMBOSIS affecting?
CN V (1)
A patient has a stabbing pain on his upper lip. Which nerve is the CAVERNOUS SINUS THROMBOSIS affecting?
CN V (2)
From what is the ANTERIOR CRANIAL FOSSA formed?
- orbital plates of frontal bone
- jugum of sphenoid
- lesser wings of sphenoid
- crista galli and cribriform plate of ethmoid
What goes through the OLFACTORY FORAMINA?
olfactory nerve (CN I)
What surrounds the OLFACTORY BULB?
subarachnoid space with CSF
What provides attachment for the FLAX CEREBRI in the ANTERIOR CF?
CRISTA GALLI
What usually goes through the FORAMEN CECUM?
emissary vein
How might a fracture of the floor of the ANTERIOR CF result in leakage of CSF from the nose?
the OLFACTORY BULB is surrounded by CSF and is connected to the nasal opening via cribriform plates; subarachnoid space and nasal cavity are in continuity
What is CSF RHINORRHEA?
when a cribriform fracture causes the CSF surrounding the olfactory bulb to leak out the nose
How might a fracture of the floor of the ANTERIOR CF result in decreased sensitivity to smell? Can the sense of smell be regained?
it would sheer off olfactory nerves (CN I); yes, because stem cells within the olfactory epithelium can regenerate after injury
What is HYPOSMIA/ANOSMIA?
decreased sense of smell
From what structures is the MIDDLE CF formed?
- sphenoid bone (TUBURCULA SULLAE, sphenoid sinus, ANTERIOR CLINOID, DORSUM SELLAE)
- temporal bone (SUPERIOR PETROSAL PROCESSES)
- parietal bone
What is the ANTERIOR CLINOID?
medial sides of the lesser wings of the sphenoid bone; “clinoid” means “4-poster bed”; in MIDDLE CF
What covers the PITUITARY GLAND in the MIDDLE CF?
DIAPHRAGMA SELLAE
Where is the OPTIC CANAL?
between the lesser wing and body of the sphenoid
What goes through the OPTIC CANAL?
optic nerve (CN II) and opthalmic ARTERY
What is the path of CN II from the OPTIC CANAL to the OCCIPITAL LOBE?
OPTIC CANAL–>optic tracks–>lateral geniculate nucleus of the thalamus–>primary visual cortex in the OCCIPITAL LOBE
Where is the SUPERIOR ORBITAL FISSURE?
between the greater and lesser wings of the sphenoid
Which structures go through the SUPERIOR ORBITAL FISSURE?
ocular motor = CN III, CN IV, CN VI
sensory = CN V (1)
vascular = superior opthalmic VEIN
What goes through the FORAMEN ROTUNDUM?
CN V(2) (then enters pteygopalatine fossa)
When CN V(2) enters the PTERYGOPALATINE FOSSA, what does it branch into?
INFRAORBITAL, POSTERIOR and INTRA-ALVEOLAR nerves
Where is the INFERIOR ORBITAL FISSURE?
between the orbit and pterygopalatine fossa
What passes through the INFERIOR ORBITAL FISSURE?
- infraorbital nerve (CN V(2) ) [–>to infraorbital canal]
- infraorbital artery/vein
- zygomatic nerve
Where is FORAMEN OVALE located?
posterior to FORAMEN ROTUNDUM
What passes through FORAMEN OVALE?
- CN V(3) [–>to infratemporal fossa –> to muscles of mastication]
- lesser petrosal nerve
- accessory meningeal artery
Where is FORAMEN SPINOSUM located?
posterolateral to foramen ovale
What passes through FORAMEN SPINOSUM?
middle meningeal artery/vein (artery has a groove)
Where is FORAMEN LACERUM?
lateral to carotid canal; opening partially occluded by cartilage
What structures pass through FORAMEN LACERUM?
- carotid artery with venous and sympathetic nerve plexus [into circle of Willis]
- Greater petrosal nerve [pre-ganglionic, PNS]
- Deep Petrosal nerve [post-ganglionic, PNS]
- Meningeal branch of ascending pharyngeal artery
Which two nerves come together to form the NERVE OF THE PTERYGOID CANAL?
greater and deep petrosal nerves
Where does the GREATER PETROSAL NERVE synapse after it goes through the PTERAGOID CANAL?
synapses in the CILLIARY GANGLION [then goes to lacrimal, nasal, and palatine mucosal glands]
If a pituitary tumor grows superiorly, which physical sign/symptom might occur?
because the pituitary gland is in the hypophyseal fossa and the optic chiasm is located superior to it, the tumor might grow into the fibers, causing VISUAL FIELD DEFECTS
What resides in the HYPOPHYSEAL FOSSA of sella turcica?
PITUITARY GLAND
What makes up the POSTERIOR CF?
part of sphenoid bone, the sphenoid/mastoid part of the temporal bone and part of the parietal and occipital bones
What two important structures are housed in the POSTERIOR CF?
CEREBELLUM and BRAINSTEM
Where is the INTERNAL ACOUSTIC MEATUS located?
on the temporal bone in the POSTERIOR CF
What passes through the INTERNAL ACOUSTIC MEATUS?
CN VII, VIII, labyrinthine artery/vein
Describe the path of the FACIAL NERVE from the INTERNAL ACOUSTIC MEATUS.
IAM–>FACIAL CANAL—>branches to lacrimal, sublingual, submandibular and nasal glands
What are the two functions of CN III?
hearing and balance
What structure does the LABYRINTHINE ARTERY and VEIN supply?
inner ear
What goes through the JUGULAR FORAMEN?
CN IX, X, XI, meningeal artery, sigmoid sinus, inferior petrosal sinus, internal jugular vein
Which structures pass through the FORAMEN MAGNUM (unpaired)?
medulla, CN XI, vertebral arteries, spinal arteries
Which structures pass through the HYPOGLOSSAL CANAL?
CN XII [to provide motor innervation to tongue; 4 intrinsic, 3 extrinsic]
What structures are in the INCISIVE FOSSA?
nasopalatine nerve and (sometimes) the nasopalatine artery
What structures pass through the GREATER PALATINE FORAMEN?
greater palatine nerve/artery (hard palate)
What structures pass through the LESSER PALATINE FORAMEN?
lesser palatine nerve/artery
What passes through the STYLOMASTOID FORAMEN?
CN VII to supply motor innervation
Where is the PHARYNGEAL TUBERCLE located? What is attached to it?
in front of FORAMEN MAGNUM; attached by the pharyngeal raphe that makes up the walls of the pharynx
What is the CONDYLAR CANAL and what goes through it?
an inconstant opening allowing the passage of emissary veins
Where is the PTERYGOID CANAL located?
just anterior to FORAMEN LACERUM
Which structures go though the PTERYGOID CANAL?
deep petrosal nerve (post-ganglionic SNS traces this nerve), greater petrosal nerve (branch of CN VII carrying pre-ganglionic PNS fibers)
A tumor, called a Schwannoma (neuroma) may arise from cells surrounding the VESTIBULOCOCHLEAR NERVE. A Schwannoma can also affect the function of the FACIAL NERVE if the tumor is located in which passage within the skull?
INTERNAL ACOUSTIC MEATUS
Increased intracranial pressure can cause herniation of portions of the cerebellum through which opening in the cranial cavity?
FORAMEN MAGNUM
What bones are on the floor of the TEMPORAL FOSSA?
the bones in the region of the PTERION (frontal, parietal, temporal, sphenoid)
Which muscle is in the TEMPORAL FOSSA? Where does it insert?
temporalis muscle; inserts into the bone of the skull (originates at coronoid process)
Where is the INFRATEMPORAL FOSSA located?
inferior to the zygomatic arch, deep to ramus of the mandible and posterior to the maxilla
What muscles are in the INFRATEMPORAL FOSSA?
Temporalis, lateral pterygoid, medial pterygoid
Which blood vessels are in the INFRATEMPORAL FOSSA?
- Maxillary artery (middle meningeal, inferior alveolar)
- pterygoid (deep temporal, muscular branches)
- pterygopalatine (posterior superior alveolar, infraorbital, artery of pterygoid canal, descending palatine, sphenopalatine)
Which nerves/nervous structures are in the INFRATEMPORAL FOSSA?
- CN V(3): muscular branches, buccal (sensory), auriculotemporal (through otic ganglion), inferior alveolar, lingual (taste to ant 2/3 tongue)
- CN VII: Chorda tympani [through otic ganglion with lesser petrosal and auriculotemporal n]
- otic ganglion
Which kind of joint is the TEMPOROMANDIBULAR JOINT (TMJ)? What actions can it do?
-hinge type of synovial joint [between mandibular condyle and mandibular fossa]
Which ligaments connect the MANDIBLE to the CRANIUM?
lateral ligament, stylomandibular ligament, phenomandibular ligament
Which ligament in the TEMPOROMANDIBULAR JOINT (TMJ) limits jaw movement?
sphenomandibular ligament
A patient come to the ER holding her jaw. She was yawning and her jaw popped out of its socket. What kind of dislocation occurred and how do you fix the dislocation?
- anterior dislocation due to spasms of pterygoid muscles
- push down and in
Which structures pass through the PTERYGOPALATINE FOSSA?
- maxillary artery/nerve
- infraorbital nerve
- sphengopalatine artery
- nerve of pterygoid canal
- greater and lesser palatine nerves
What does the MAXILLARY artery pass through to get into the PTERYGOPALATINE FOSSA?
pterygomaxillary fissure
What does the INFRAORBITAL NERVE pass through to get into the PTERYGOPALATINE FOSSA? To get out?
- in = inferior orbital fissure
- out = infraorbirtal canal
What does the SHENOPALATINE ARTERY pass through to get into the PTERYGOPALATINE FOSSA?
sphenopalatine foramen
What does the MAXILLARY NERVE pass through to get into the PTERYGOPALATINE FOSSA?
foramen rotundum
What does the NERVE OF PTERYGOID CANAL pass through to get into the PTERYGOPALATINE FOSSA?
pterygoid canal
What does the GREATER PALATINE NERVE pass through to get into the PTERYGOPALATINE FOSSA?
greater palatine foramen
What does the LESSER PALATINE NERVE pass through to get into the PTERYGOPALATINE FOSSA?
lesser palatine foramen
What structure does the LESSER PALATINE NERVE ultimately innervate?
hard palate
What structure does the GREATER PALATINE NERVE ultimately innervate?
soft palate
TEMPORALIS MUSCLE
O: temporal fossa
I: coronoid process
N: CN V3
A: elevates/retracts mandible; closes mouth
MASSETER MUSCLE
O: zygomatic arch
I: lateral surface and angle of mandible (NOT in temporal fossa)
N: CN V3
A: elevates mandible; closes mouth
LATERAL PTERYGOID MUSCLE
O:greater wing and lateral pterygoid plate
I: TMJ capsule and condyloid process
N: CN V3
A: Bilateral = protracts mandible and depresses (opens mouth) chin; unilateral = large chewing
MEDIAL PTERYGOID MUSCLE
O: lateral pterygoid plate
I: ramus of mandible (medial surface)
N: CN V3
A: Bilateral = elevates mandible; protrudes chin; Unilateral = small chewing motions
What is the ONLY muscle that OPENS the mouth actively?
lateral pterygoid muscle
The ARTICULAR DISC of the TMJ joint has 2 compartments. What are they and what does each do?
- sliding movements = upper compartment [loose fibers]
- rotation movements = lower compartment [tight connections]
As the jaw opens, the mandible slides _____.
Forward
From which vessel does the MANDIBULAR ARTERY come?
external carotid artery
Which artery goes through the MENTAL FORAMEN and from which vessel does it branch from?
mental branch of INFERIOR ALVEOLAR ARTERY; comes from MAXILLARY ARTERY
To which structure does the SPHENOPALATINE ARTERY go and from which vessel does it branch?
- nasal septum
- maxillary artery
To which structure does the DESCENDING PALATINE ARTERY go and from which vessel does it branch?
- to hard/soft palates
- maxillary artery
Which vessel does the V3 branch of the TRIGEMINAL nerve form a circle around near a person’s temple?
middle meningeal artery
Describe the PNS nerve path of CN IX to the PAROTID GLAND.
Brain (CN IX)—->jugular foramen—> (tympanic n.) through tympanic canaliculus—>middle ear—>tympanic plexus—>through hiatus of lesser petrosal n./foramen ovale—>SYNAPSE at otic ganglion (follows V3)—>PAROTID!!!
What is the name of the oral cavity that opens to the environment?
ORAL FISSURE
What is the name of the structure that opens to the oral part of the pharynx?
OROPHARYNGEAL ISTHMUS
What is the ORAL VESTIBULE?
between teeth and the cheeks
What are the functions of the HARD PALATE?
phonation (speech), food compression, attachment site for upper teeth
Which foramina does the HARD PALATE have?
- Incisive fossa [posterior to central incisor teeth]
- Greater palatine foramina (x2) [medial to 3rd molar tooth
- Lesser palatine foramina (x2) [posterior to greater palatine foramina]
What goes through the INCISIVE FOSSA?
NASOPALATINE nerves/vessels (from nose)
What are the main functions of the SOFT PALATE?
allow for swallowing food bolus without the bolus going up into the nasal cavity, lowered for breathing through nose
Which muscles make up the SOFT PALATE?
- Tensor veli palatini
- Levator veli palatinai
- Palatoglossus
- Palatopharyngeus
- Musculus uvulae
Which muscles does the VAGUS nerve innervate in the SOFT PALATE?
- Levator veli palatinai
- Palatoglossus
- Palatopharyngeus
- Musculus uvulae
Which muscles does CN V3 innervate in the SOFT PALATE?
TENSOR VELI PALATINI
The hard and soft palates receive their sensory innervation via branches of _________.
CN V2
Parasympathetic and special sensory innervation hitchhikes along branches of _______ to reach the palates.
CN V2
Where does the NASOPALATINE NERVE provide information? What kind?
- to anterior region of hard palate
- sensory
Where does the GREATER PALATINE NERVE provide information? What kind?
- hard palate
- general sensory
Where does the LESSER PALATINE NERVE provide information? What kind?
- soft palate
- general sensory
In the soft palate, the PARASYMPATHETIC nerves originate from the ________ nerve of CN ____ via the pterygopalatine ganglion. These fibers then travel with the __________ nerve and ________ nerve.
- greater petrosal
- VII
- greater palatine
- lesser palatine
In the soft palate, the TASTE (special sensory) fibers travel with the ____ and ____ nerves to the _____ nerve of CN _____.
- greater palatine
- lesser palatine
- greater petrosal
- VII
Name the 3 arteries of the palate and which main branch each comes from.
- Greater palatine a. = maxillary a.
- Lesser palatine a. = maxillary a.
- Ascending palatine = facial a.
The ________ is the primary muscle of the the lips and the _______ is the primary muscle of the cheeks.
- orbicularis oris
- buccinator
The _____ and ______ arteries supply the UPPER LIP and the _____ and ______ supply the LOWER LIP.
- superior labial branches (of facial a.)
- infraorbital arteries
- inferior labial branches (of facial a.)
- mental arteries
The ________ branches of the _______ artery supply the CHEEKS.
- buccal
- maxillary
The _____ of _____ nerves innervates the UPPER LIP and the _____ of ______ nerves innervates the LOWER LIP.
- superior labial branches
- infraorbital nerves (V2)
- inferior labial branches
- mental nerves (V3)
The ____ branches of the ______ nerve innervate the CHEEKS.
- buccal
- mandibular (V3)
What are the LABIAL FRENULA?
folds of mucous membrane in the midline of the upper, lower lips and within oral vestibule
What is superior to the BUCCINATOR MUSCLES?
buccal fat pads
Name the 3 parts of a tooth:
- crown
- neck
- root
Name the 4 types of teeth. How many of each are there on one half of the mouth on the superior part?
- Incisors (2)
- Canines (1)
- Premolars (2)
- Molars (3)
What innervates the UPPER TEETH? The LOWER TEETH?
- CN V2
- CN V3
Which arteries supply the TEETH?
- superior/inferior alveolar arteries
2. branches of the maxillary artery
What are the muscles that make the floor of the ORAL CAVITY? What is their action?
- geniohyoid
- mylohyoid
- depress the mandible (retraction)
MYLOHYOID MUSCLE innervation
the nerve to the mylohyoid muscle (branch of CN V3)
GENIOHYOID MUSCLE innervation
(paired, cord-like muscles) branch of ansa cervicalis that courses with hypoglossal nerve XII
What delineates the anterior 2/3 (oral part) and posterior 1/3 (pharyngeal part) of the tongue?
terminal sulcus (V-shaped groove)
How many INTRINSIC TONGUE muscles are there and what do they do?
- 4
- alter tongue shape (roll tongue)
Name the 4 EXTRINSIC TONGUE muscles. What are the functions?
- Genioglossus
- Hyoglossus
- Styloglossus
- Palatoglossus
- move position of tongue
Describe the MOTOR innervation of the tongue.
- All innervated by XII except
- Palatoglossus, which is innervated by pharyngeal branch of CN X
A patient is asked to protrude their tongue. The tongue deviates to the left. Which nerve is injured? Which muscle?
- Left CN XII [“lick their wound”]
- Genioglossus
General sensory info from the anterior 2/3 of tongue comes from the _______. Special sensory innervation comes from the ______.
- Lingual n. (branch of CN V3) {ex. cold, hot, rough, etc.}
- Chorda tympani n. (branch of VII) {ex. sweet}
General sensory info from the posterior 1/3 of tongue comes from the _______. Special sensory innervation comes from the ______.
- lingual branch of GLOSSOPHARYNGEAL n (CN IX)
- lingual branch of CN IX
The _______ artery (branch of ____) supplies the tongue: _____ arteries supply the root and _______ supply the anterior part of the tongue
- Lingual
- External Carotid Artery
- dorsal lingual
- deep lingual
Which veins supply the tongue?
dorsal and deep lingual veins—>IJV
Which 3 structures make up the POSTERIOR ORAL CAVITY?
- palatoglossal arch (ventral)
- palatopharyngeal arch (dorsal)
- palatine tonsils (lymphatic tissue)
All the muscles of mastication close the jaw except the ______, which OPENS the JAW.
lateral pterygoid muscle
The PAROTID DUCT goes through the _____ muscle and enters the oral cavity next to the ________.
- buccinator
- superior 2nd molar
What kind of nerves PNS innervate the PAROTID gland? Where does the preganglionic nerve synapse?
- glossopharyngeal
- synapses at otic ganglion
Sympathetic innervation of the PAROTID gland is derived from _______ ganglia through ______ plexus. What is the function of this innervation?
- cervical ganglia
- external carotid nerve plexus
- vasoconstriction to prevent salivation
The which duct is between the mylohyoid and hyoglossus muscles, opening in 1-3 orifices at lingual frenulum?
Submandibular duct
What kind of nerves PNS innervate the SUBMANDIBULAR gland? Where does the preganglionic nerve synapse?
- fibers in chorda tympani (CN VII)
- submandibular ganglion
Sympathetic innervation of the SUBMANDIBULAR gland is derived from _______ ganglia and travel along these vessels. What is the function of this innervation?
- superior cervical ganglia
- vasoconstrictor
What arteries supply the SUBMANDIBULAR GLAND?
submental arteries
Which type of duct opens into the floor of the mouth along the folds?
sublingual
What kind of nerves PNS innervate the SUBLINGUAL gland? Where does the preganglionic nerve synapse?
- fibers in chorda tympani (CN VII)
- submandibular ganglion
Sympathetic innervation of the SUBLINGUAL gland is derived from _______ ganglia and travel along these vessels. What is the function of this innervation?
- superior cervical ganglia
- vasoconstrictor
Which arteries supply the SUBLINGUAL GLAND?
submental and sublingual
The initial stage of swallowing is ______ and requires the _____ to move anteriorly for the bolus to enter the pharynx. The second stage is ______ and involves ____ movements that constrict the esophagus in waves.
- voluntary
- soft palate (epiglottis)
- involuntary
- parastalsis
Why do kids tend to have a higher incidence in middle ear infections after an upper respiratory infection?
Because kids’ pharyngeal tube (auditory tube) is bigger (bigger torus tubarius) and more horizontal and so when they blow their nose hard, bacteria will enter the middle ear.
Why is there so much lymphatic tissue in the pharynx?
to fight potential pathogens
Which muscle is bent around the PTERYGOID HAMULUS?
Tensor veli palatini
Which two bones make up the hard palate?
maxilla and palatine
Which tooth has 2 sensory nerve supplies? Which nerves are they?
- 3rd superior molar
- middle superior alveolar and posterior superior alveolar nerves (CN V2)
The doctor asks the patient to lift his tongue upward. He is using which extrinsic muscle? Now the doctor asks the patient to move his tongue to the right. He is using which extrinsic muscle?
- levator veli palatini
- tensor veli paatini
Which muscle is associated with the PHARYNGEAL TUBE opening?
Tensor veli palatini
Why, in adults, when you take an airplane flight when you have an upper respiratory infection are you prone to middle ear infections?
When you reach altitude, the change in pressure causes you to equalize your ear drum that is pulled outward (concave); then when you come down from the flight, your ear drum is pulled in (convex) do to another pressure change so that when you plus and blow your nose, a ton of bacteria goes up into your middle ear through your pharyngeal tube.
Are palatine tonsils very or not very vascular?
VERY
The MAXILLARY SINUS drains into what structure in the nose?
Middle meatus
A patient comes in with an awful sinus infection, complaining of painful pressure near his cheekbones. He also complains of another symptom. What is it?
excessive runny nose because of draining into middle meatus
A patient comes into the office because she is having problems getting food stuck in her oral vestibule. She only can get it out with her finger. Which muscle is atrophied?
buccinator
Which nerve innervates all the lower teeth?
inferior alveolar nerve (CN V3)
Which branches of the inferior alveolar nerve innervates the 3 molars and 1 1/2 premolars on the lower jaw? How about the 1/2 premolar and 3 incisors?
- dental branch
- incisive branch
The anterior 2/3 of the tongue is supplied by nerves of which 2 arches? Which nerves associate with them?
- Arch 1 = CN V3 (lingual n.)
- Arch 2 = Chorda tympani (CN VII)
The posterior 1/3 of the tongue is supplied by nerves of which 2 arches? Which nerves associate with them?
- Arch 3 = [GSA and taste] CN IX
- Arch 4 = [GSA and taste] CN X (internal laryngeal)
A patient arrives at the ER with a myocardial infarction. He needs meds (nitroglycerine) as quick as possible and he has no IV in him yet. Where should the doctor place the medicine?
underneath his tongue because there are many deep and dorsal lingual arteries/veins that the meds will diffuse into quickly (<1 min)
