Gross Block B Flashcards
enteric nervous system is involved with
the gut
Cerebrum is composed of 3 parts
cortex, basal ganglia, and thalamus
basal ganglia is associated with
movement
thalamus is aka
diencephalon
thalamus is a relay to
the senses
4 basic parts of the CNS
cerebrum, brainstem, cerebellum, and spinal cord
3 parts of brainstem
midbrain, pons, medulla
optic chiasm-
bridge between 2 optic nerves before they separate
CN 1 =
olfactory nerve
CN 1 exit
cribiform plate
CN 1 components
SVA
main action of CN1
smell
CN2 =
optic nerve
CN2 exit
optic canal
CN2 components
SSA
main action of CN2
vision
CN3 =
occulomotor nerve
CN3 exit
superior orbital fissure
cn3 components
GSE, GVE
main function of cn3
eye movements, accomodation
cn4 =
trochlear nerve
cn4 exit
superior orbital fissure
cn4 components
GSE
cn4 main function
eye movements and accomodation
cn5 =
trigeminal nerve
cn5 exits
V1- superior orbital fissure
V2- foramen rotundum
V3- Foramen Ovale
cn5 components
GSA, SVE
cn5 main actions
sensor of head, dura, jaw movement
cn6 =
abducens nerve
cn6 exit
superior orbital fissure
cn6 components
GSE`
cn6 main function
eye movements, accomodation
cn7 =
facial nerve
cn7 exit
internal acoustic meatus
cn7 components
SVA, GVE, SVE, GSA
cn7 main actions
muscles of facial expression, taste, saliva, tearing
cn8 =
vestibulocochlear nerve
cn8 components
SSA
cn8 main actions
hearing and balance
cn9 =
glossopharyngeal nerve
cn9 exit
jugular foramen
cn9 components
SVE, SVA, GVA, GVE
cn9 main actions
taste, saliva, visceral sensor
cn10 =
vagus nerve
cn10 exit
jugular foramen
cn10 components
SVE, GVA, GVE
cn10 main actions
swallowing, speaking, visceral sensor, main component of parasympathetic
cn11 =
spinal accessory nerve
cn11 exit
jugular foramen
cn11 components
GSE
cn11 main actions
motor to trapezius and sternocleidomastoid
cn12 =
hypoglossal
cn12 exit
hypoglossal canal
cn12 components
GSE
cn12 actions
motor to tongue
cn13 =
spinal cord
epidural space of skull is _____ space
potential
______ is pushed up against dura mater in skull
arachnoid
subdural space is _____ space
potential
subarachnoid space contains
CSF and blood vessels held between arachnoid and pia
what meningeal layer is intimate with the brain
pia mater
brain is suspended by
arachnoid trabecula
dura is very sensitive, well innervated by what nerves?
CN 5, CN 10, C2, C3
the nerve supplying dura mater generally follow
arteries
dura has own blood supply via
middle meningeal artery
dura has what 2 layers
periosteal and meningeal
periosteal/meningeal layers split in what 4 places
falx cerebri, dural sinuses, tentorium cerebelli, and tentorial incisura
falx cerebri-
sickle-shaped double layer of dura mater lying between the cerebral hemispheres. divides the two hemispheres
dural sinuses-
spaces between the periosteal and meningeal layers of dura
large veins from surface of the brain empty into _______ and most of the blood from teh brain ultimately drains through them into the _______
- dural sinuses
- internal jugular veins
tentorium cerebelli-
separates cerebrum from cerebellum
tentorium cerebelli divides the cranial cavity into
supratentorial and infratentorial spaces
supratentorial space contains
cerebrum, telencephalon, and diencephalon
infratentorial space contains
cerebellum and brainstem
most pediatric brain tumors are in the ______ space
infratentorial
most adult brain tumors are in the ______ space
supratentorial
tentorial incisura/tentorial notch-
opening in the tentorium cerebelli for the passage of brainstem
CSF is produced in
choroid plexuses of ventricles
choroid plexuses are ______ cells that line all 4 ventricles of brain
epithelial (modified ependymal)
We produce ___ cc of CSF/hour
20
CSF is absorbed by _____ and goes back into venous circulation
arachnoid villi
which ventricles are largest
lateral ventricles
each lateral ventricle opens through an ______ into the 3rd ventricle
interventricular foramen (foramen of Monro)
which ventricle is located between the 2 halves of the thalamus
3rd ventricle
3rd ventricle is connected to the 4th ventricle via the
cerebral aqueduct
4th ventricle is ____ shaped
pyramid
4th ventricle is located within
pons/upper medulla
4th ventricle is where CSF leaves the ventricular system via ________ to enter subarachnoid space
median and lateral apertures
arachnoid granulations/villi-
small projections of arachnoid mater into the superior sagittal sinus
what is the main site of CSF absorption into the venous system
arachnoid villi/granulations
CSF goes pathway:
ventricles–>subarachnoid space–>arachnoid granules–> superior saggital sinus–> internal jugular veins
brain is __ % body mass but takes up ___% of blood supply, ___% of glucose, and ___% of O2
- 2
- 20
- 25
- 20
85% of strokes are
15% are
- occlusive
- hemorrhagic
circle of willis consists of what arteries (5)
posterior cerebral artery (PCA), Posterior communicating artery (PComA), Internal carotid artery (ICA), Anterior cerebral artery (ACA), and Anterior communicating artery (AComA)
Circle of willis isnt always complete. Most often missing artery is
anterior communicating artery
basic layout of venous drainage in the brain is brain–>?
–>dural venous sinuses–>internal jugular veins
dural venus sinuses are located
between the 2 layers of dura
superior saggital sinus-
dural venous sinus that lies in convex attached border of teh falx cerebri. Major sinus along superior medial portion of the brain
5 dural venous sinuses to know
superior saggital sinus, straight sinus, transverse sinus, sigmoid sinus, inferior and superior petrosal sinus.
confluence of sinuses-
point where superior saggital, straight, occipital and transverse sinuses meet
blood collected in the confluence of sinuses is drained by
the transverse sinus
the transverse sinus becomes the
sigmoid sinus
sigmoid sinus drains into the
internal jugular vein
cavernous sinus-
large venous plexus located on each side of the sella turcica on the upper surface of the body of the sphenoid
a lot of traffic comes through the cavernous sinus, including what 6 things
internal carotid artery, CN 6, 3, 4, 5(V1 and 2)
name the only place in the body where a major artery passes through a pool of venous blood
cavernous sinus
danger zone-
cavernous sinus. if infection enters it, it can easily be transferred to the brain
cavernous sinus allows for heat exchange between
venous blood in cavernous sinus and ICA
non communicating hydrocephalus-
occlusion of CSF through ventricles
communicating hydrocephalus
normal pressure hydrocephalus. arachnoid villi arent taking up CSF, resulting in too much volume
communicating hydrocephalus has acute/chronic onset?
acute
common solution to communicating hydrocephalus
use a shunt: run a tube from ventricle to peritoneal cavity
communicating hydrocephalus is common in what age group
elderly
The communicating hydrocephalus triad
mental decline, urinary incontinence, and magnetic gait
5 major parts of the brain:
telencephalon, diencephalon, brain stem, cranial nerves, ventricles
telencephalon structures
neocortex, limbic, basal ganglia
telencephalon is responsible for
perception, thinking, emotion, memory, drives
diencephalon structures
thalamus and hypothalamus
diencephalon is responsible for
filtering of senses, motor relay, visceral ‘brain’ (hypothalamus)
brain stem structures
midbrain, pons, medulla
midbrain is home to what CNs
3 and 4
pons is home to what CNs
5, 6, 7, 8
medulla is home to what CNs
9, 10, 11, 12
surgeons avoid sulci because
that is where veins and arteries tend to cozy up
glial cells outnumber neurons in what ratio
10:1
2 major types of glial cells
oligodendroglia and astroglia
oligodendroglia
responsible for CNS myelination
astroglia
support cells, establish BBB
what chemical is injected in blood to show efficacy of BBB
horseradish peroxidase
where are your superciliary arches
above the eyebrows
what 2 processes lie on the temporal bone
mastoid process and styloid process
pterion-
area formed by the frontal bone, parietal bone, greater wing of sphenoid bone, and the temporal bone
what is just inside the pterion
middle meningeal artery
lambda-
point where the lambdoid suture joins the superior saggital suture
bregma-
point where the coronal suture joins the sagittal suture
asterion-
junction of three sutures (parietomastoid, occipitomastoid, and lambdoid)
inion-
most prominent point of external occipital protuberance
glabella-
smooth prominence above the nasion
SCALP covers the
calvaria
SCALP stands for-
skin, connective tissue, aponeurosis, loose connective tissue, and periosteum
superficial infections of the scalp tend to remain superficial because
the fibrous tissue is dense
the 2 main arteries contributing blood to the scalp
external and internal carotid arteries
branches of the external carotid artery that supply the scalp(3)
occipital artery, posterior auricular artery, and superficial temporal artery
internal carotid branches of the scalp (2)
supratrochlear and supraorbital arteries (which branch from the opthalmic artery that branched from the internal carotid)
2 dorsal rami that supply the scalp
greater occipital nerve (C2) and Third occipital nerve (C3)
2 ventral rami that supply the scalp
greater auricular nerve (C2, C3) and lesser occipital nerve (C2, C3)
4 divisions of CN 5 that supply the scalp
auriculotemporal nerve (V3), zygomaticotemporal nerve (V2), supratrochlear nerve (V1), supra-orbital nerve (V1)
galea aponeurotica-
aponeurosis + epicranius muscle
epicranius muscle-
muscles of facial expression
Danger area of scalp-
loose connective tissue layer, especially near the frontalis muscle. Infection can enter the skull via emissary veins
emissary veins-
go from the outside to inside of skull
diploic veins-
veins in between the outer and inner layer of the skull
diploic veins can make connections with _______ veins
emissary
where is the pericranium continuous with the endocranium?
at the sutures and foramina
SMAS stands for
superficial musculo-aponeurotic system
SMAS extends from where to where?
platysma muscle to galea aponeurotica
SMAS is continuous with ______ and _______
temporoparietal fascia and galea aponeurotica
what is risorious m. for?
smiling
buccinator muscle is found in
the cheek
Facial nerve sends out a _________ branch which supplies some of the posterior muscles and occipitalis muscle
posterior auricular branch
posterior auricular nerve innervates
posterior auricular muscle and occipitalis muscle
4 motor branches of facial nerve
temporal, zygomatic, buccal, marginal mandibular, cervical
marginal mandibular branches of facial nerve go towards
the mouth
if facial nerve is damaged immediately after the stylomastoid foramen, what will happen?
all the muscles of facial expression will be knocked out
if damage to facial nerve is immediately after the genticulate ganglion, then what will happen?
all muscles of facial expression will be knocked out as well as the other functions of CN VII
largest cranial nerve
cranial nerve
trigeminal nerve originates from the
trigeminal ganglia located in the skull
3 branches of trigeminal nerve
opthalmic, maxillary, and mandibular
which branch of trigeminal nerve has motor innervation
V3
the ____ segment of V3 is deep to the _____ segment
motor; sensory
opthalmic division (V1) gives off what branches? (5)
supraorbital, supratrochlear, infratrochlear, lacrimal, and external nasal nerves
branches of maxillary division (V2)`
infraorbital, zygomaticofacial, and zygomaticotemporal nerves
branches of mandibular division (V3) (sensory)
buccal, mental, and auriculotemporal nerves
buccal nerve pierces _____ and supplies ______ (sensory)
- buccinator
- mucosa on inside of cheek
mental nerve supplies __________ (sensory)
mucosa of gingiva and skin of the chin
the nerves that supply sensory to the face-
V1, 2, 3, and the greater auricular nerve
trigeminal neuralgia-
sudden attack of excruciating pain along distribution of maxillary, mandibular, or opthalmic divisions of trigeminal nerve
causes of trigeminal neuralgia-
aberrant blood vessels, aneurysms, brain tumor compressing trigeminal root.
treatment for tic douloureux-
usually just have to cut sensory root
facial artery branches into
superior and inferior labia arteries
superficial temporal artery runs anterior to
ear
facial vein is sometimes referred to as
angular vein
superficial temporal vein and maxillary vein join to form
retromandibular vein
retromandibular vein divides and sends anterior branch that joins with ______ to become ______
anterior facial vein
common facial vein
retromandibular vein divides and sends posterior branch that joins with ______ to become ______
posterior auricular vein
external jugular vein
external jugular vein goes diagonally across ______ and drains into ______
sternocleidomastoid muscle
subclavian vein
any infection can run back into the skull via ______, _____, ______, or ________
superior opthalmic vein, inferior opthalmic vein, dural venal sinuses, or pterygoid plexus
infection entering pterygoid plexus can cause
cavernous sinus thrombosis
parotid gland lies on _____ muscle
masseter
name 3 structures in parotid gland from superficial to deep
facial nerve, retromandibular vein, external carotid artery
parotid duct crosses over ____ muscle, penetrates _____ muscle, and opens into _________
- masseter
- buccinator
- vestibule of oral cavity opposite second maxillary molar
all sympathetics to head must synapse in
superior cervical ganglion
parasympathetic nerve to parotid gland
CN IX (inferior salivary nucleus)
what nerve component of CN IX acts on parotid gland
GVE
CN IX synapses at ________ in the infratemporal fossa before going to parotid gland
otic ganglion
subdural hematomas occur from vessels that supply the
brain
all muscles of mastication are derived from
the first pharyngeal arch
functional components of CN V3
GSA and SVE
nerves that lie in ITF
branches of V3, chorda tympani, lesser petrosal nerve, and otic ganglion
veins that lie in ITF (5)
superficial temporal, pterygoid plexus, maxillary, deep facial, and retromandibular
2 major foramen of ITF
foramen ovale and spinosum
foramen spinosum is anterior/posterior to foramen ovale?
posterior
groove leading up to foramen spinosum is created by
MMA that enters this foramen
pterygoid fovea location
anterior-medial face of head of mandible
intrinsic ligaments of TMJ
joint capsule and lateral ligament
extrinsic ligaments of TMJ
stylomandibular ligament and sphenomandibular ligament
stylomandibular ligament runs from _______ to ______
styloid process of temporal bone to posterior aspect of mandible
sphenomandibular ligament runs from ____ to ____
spine of sphenoid to lingula of mandible
what is the main ligament of the TMJ
sphenomandibular ligament
______ serves as the check ligament to prevent excessive motion of the mandible
sphenomandibular ligament
________ acts as a fulchrum for jaw movement
sphenomandibular ligament
what kind of joint is TMJ
modified hinge joint
actions of superior cavity of TMJ
protrusion/retrusion
actions of inferior cavity of TMJ
depression, elevation, and rotation
pain from jaw dislocation is transmitted via what nerves?
auriculotemporal, and masseteric nerves
lateral pterygoid m inserts on __________
pterygoid fovea and articular disc
all muscles of mastication are derivatives of
first pharyngeal arches
distal attachment of temporalis m
coronoid process of mandible and anterior border of ramus of mandible
action of temporalis m
the major elevator of mandible. also retracts the jaw
masseter m proximal and distal attachments
zygomatic arch and ramus of mandible/coronoid process of mandible
action of masseter m
elevator and protruder of mandible
which 2 muscles of mastication form a powerful sling with each other around the angle of the mandible?
masseter and medial pterygoid
proximal attachments of medial pterygoid
superficial head- tuberosity of maxilla and pyramidal process of palatine bone
deep head- medial surface of lateral pterygoid plate
distal attachment of medial pterygoid m.
medial surface of ramus and angle of mandible
action of medial pterygoid muscle
elevate and protrude the mandible
proximal attachments of lateral pterygoid m
superior head- infratemporal surface and crest of greater wing of sphenoid bone
inferior head- lateral surface of lateral pterygoid plate
distal insertion of lateral pterygoid m
joint capsule and articular disc of TMJ; pterygoid fovea
action of lateral pterygoid m
protrudes mandible, initiates jaw opening, and lateral mandibular movements
the only muscle that actively opens and protrudes the jaw
lateral pterygoid muscle
the maxillary artery usually sits superficially to the _____ muscle
lateral pterygoid
CN V3 is mostly sensory/motor?
sensory
components of CN V3
GSA and SVE
Where does CN V3 leave skull?
foramen ovale
besides muscles of mastication, what 4 muscles does CN V3 innervate?
mylohyoid, anterior belly of diagastric, tensor tympani, and tensor veli palatini
undivided trunk of CN V3 exits foramen ovale then splits to give off what 2 divisions
anterior and posterior divisions
2 motor nerves coming off undivided trunk of CN V3
tensor tympani, tensor veli palatini, and medial pterygoid nerves
sensory nerve coming off undivided trunk of CN V3`
recurrent meningeal nerve
4 nerves coming off anterior division of CN V3
masseteric, deep temporal, lateral pterygoid, and long buccal nerves
masseteric nerve-
travels thru mandibular notch to masseter muscle and does a little bit of sensory innervation to the TMJ
deep temporal nerves innervate
temporalis muscle
components of nerve to lateral pterygoid
GSA GSE
long buccal nerve is sensory to
skin and mucosa of cheek.
long buccal nerve travels in between
the 2 heads of the lateral pterygoid muscle
2 major branches of posterior division of CN V3
lingual and inferior alveolar nerves
inferior alveolar nerve travels through what structure
mandibular foramen
inferior alveolar nerve emerges from mental foramen as _____ nerve
mental
inferior alveolar nerve has a motor branch that innervates
mylohyoid muscle and anterior belly of diagastric muscle
lingual nerve supplies-
mucosa of anterior 2/3 of the tongue, mucosa of floor of mouth, and gingiva of lingual aspect of mandible
______ ganglion is suspended from lingual nerve
submandibular ganglion
what nerve hitches a ride on the lingual nerve?
chorda tympani nerve
auriculotemporal nerve branches off of-
posterior division of CN V3
what nerve loops around the MMA
auriculotemporal nerve
auriculotemporal nerve sensory innervates (6)
TMJ, Tympanic membrane, skin over parotid gland, skin of temporal region, skin of auricle, skin of external auditory canal
otic ganglion is inferior to what foramen?
foramen ovale
components of chorda tympani
SVA, GVE
chorda tympani exits skull via _______ as part of the facial nerve then travels into ______ and continues across _______ before entering the ITF
- internal acoustic meatus
- middle ear
- tympanic membrane
chorda tympani provides SVA to
anterior 2/3 of tongue (taste)`
parasympathics of chorda tympani supply
salivary glands
preganglionic parasympathetic cell bodies of chorda tympani are found in
superior salivary nucleus
parasympathetic fibers of chorda tympani synapse at
submandibular ganglion
postsynaptic parasympathetic fibers of chorda tympani supply
submandibular and sublingual glands and mucosa on floor of mouth
if you lose feeling to anterior 2/3 of tongue, what nerve is damaged?
trigeminal nerve issue
if you cannot taste, what nerve is damaged?
facial nerve
if you lose both taste and sensation to tongue, what nerve is damaged?
most likely the lingual nerve
lesser petrosal nerve is a branch of
CN IX (glossopharyngeal nerve)
lesser petrosal nerve brings parasympathetic preganglionic fibers to _________, where they synapse. The postsynaptics then leave and join the ________ nerve for distribution to the parotid gland
- otic ganglion
- auriculotemporal nerve
external carotid artery ends as what 2 arteries?
superficial temporal and maxillary
maxillary artery is divided into 3 portions:
mandibular, pterygoid, and pterygopalatine branches
4 branches of mandibular portion of maxillary artery
deep auricular, anterior tympanic, middle meningeal, and inferior alveolar arteries
what artery supplies teeth?
inferior alveolar artery
middle meningeal artery enters skull through _______
foramen spinosum
*** there is often an accessory MMA
4 branches of pterygoid portion of maxillary artery
deep temporalis, pterygoid, masseteric, and buccal arteries
buccal artery travels with
long buccal nerve
______ plexus of veins drains into the maxillary veins, which drain into _______
- pterygoid
- retromandibular vein
pterygoid plexus communicates with _______ sinus
cavernous
