Module 07A Flashcards
what is the scalp
layers of subcutaneous tissue and skin that cover the bones of the skull
how many layers of the scalp are there
5
s - of scalp
skin
skin of scalp
contains all of the epidermal appendages including hair follicles and sebaceous glands
c- scalp
dense connective tissue
dense connective tissue
this highly vascularized and innervated layer also contains hair follicles,
- scalp lacerations that penetrate this layer may bleed profusely due to rich blood supply found here
a- scalp
aponeurosis
aponeurosis
- thin, board, tendon-like sheet that covers the dome of the skull and serves as an intermediate tendon between the occipitalis muscle posteriorly and frontalis muscle anteriorly
function of the occipitalis muscle and frontalis
move the scalp, wrinkle the forehead, raise the eyebrows
l- scalp
loose connective tissue
loose connective tissue
this layer may be referred to as the ‘danger area of the scalp’
- infections can easily spread within it and enter the cranial cavity
- easy plane of separation between the upper three layers and the pericranium (the external periosteum of the skull)
p- scalp
pericranium (periosteum)
pericranium (periosteum)
thin layer of connective tissue that covers the bones of the skull
- protect the skull and provides nutrients to the bone
complication with hair transplants
- nerve damage
- prolonged pain
nerve damage of hair transplant
- numbness/lack of sensation from nerve damage and/or bleeding from vascular damage of the skin and connective tissue (dense) layers of the scalp
prolonged pain- from hair transplant
- post pain surgery is part of the normal recovery process as the follicles are healing
- pain that doesn’t subside after 4-5 weeks is abnormal and may indicate an infection of the new follicles
what are the 3 major salivary glands?
parotid gland
sublingual gland
submandibular gland
how much saliva is produce from the 3 glands?
0.5-2.0 liters a day
parotid gland- how do the secretions exit
- through stensen’s duct (parotid duct)
Stensen’s duct path
passes superficial to the masseter muscle, and then pierces the buccinator to open into the oral cavity (opposite the second upper molar tooth)
what is the largest salivary gland?
submandibular gland
where can the submandibular gland be palpated
in the neck medial to the lower border of the mandible
where do secretions of the submandibular exit
through Whartons duct (submandibular duct) into the sublingual papillae behind the lower incisors on the side of the lingual frenulum
what is the inferior part of the parotid gland sometimes referred to as
the ‘parotid tail’
salivary gland stones
- calcified stones form when chemicals in the saliva accumulate in the duct or gland
- can affect both parotid and submandibular glands
stones in the parotid gland
tend to be larger and less common
symptoms of salivary gland stone in parotid duct
- swelling of the gland and check, pain in the lower jaw near the duct, especially of eating and difficulty opening the mouth from a blockage of the flow of saliva in the duct
when do salivary gland stones occur
- randomly
- etiology is unknown
- reduce saliva production and/or thickened saliva may be risk factors for the development of salivary gland stones as they reduce the flow saliva
factors that lead to reduced/thickened salivary production
- dehydration
- poor eating
- use of certain medications (BP and bladder control)
- trauma to the salivary gland
- genetics- males have higher risk of less production
muscles of facial expression
- specialized group of voluntary muscles that protect the orifices of the face by acting as sphincters and dilators
contraction of buccinator facial muscle
- pulls the cheeks tightly against the teeth, preventing food from collecting between the teeth and gums during mastication and working in concert with the tongue to keep food between the molars
what is the 7th cranial nerve
facial nerve
facial nerve branches
- temporal
- buccal
- cervical
- zygomatic
- marginal mandibular
buccinator muscle strain
- occur from strenuous activity of the jaw such as chewing gum for extended period of time, ill-fitting mouthpieces, or contact sport injury
where would pain occur with a buccinator muscle strain?
- deep pain in the cheek that can resemble a painful cavity or even an abscessed tooth
- the strained muscle may cause pain during movements like chewing, moving food around in mouth, smiling, swallowing
what is the 5th cranial nerve
trigeminal nerve
function of cranial nerve
- carries sensory (touch, pain, temp) and motor innervation to face
what are the 3 branches of the trigeminal nerve
- mandibular (v3)
- maxillary (V2)
- ophthalmic (V1)
mandibular (v3)
- supplies the skin of lower lip, lower face, temporal region, and upper part of external ear
what branch of trigeminal only carriers motor innervation to the muscles of mastication?
mandibular (v3)
maxillary V2
innervates the skin of the lateral sides of the nose, lower eyelid, cheek, temporal region, and upper lip
ophthalmic (V1)
carries sensory information from the skin of the forehead, upper eyelid, and midline of the nose
trigeminal neuralgia
- chronic pain condition resulting from trigeminal nerve impairment
- impairment can be caused by compression of the trigeminal nerve by neighboring structures (blood vessel, tumor) multiple sclerosis (affects nerves), or natural aging process
- damage to nerve could also be from surgery
symptoms of trigeminal neuralgia
- brief periods of stabbing or shooting pain following the path of the trigeminal nerve in the teeth, jaw, upper gums
- forehead pain
- pain triggered by brushing teeth, shaving, brushing front of hair, putting on facial cream
- pain can last few seconds -> few min with multiple attach a day
how many extraocular muscles control the eye
7
horizontal axis eye movements
- elevation of the eyeball with the pupil in the midline (superior rectus and inferior oblique muscles)
- depression is facilitated by the inferior rectus and superior oblique muscles
vertical axis movements of eye
- abduction: lateral rectus muscle
- adduction: medial rectus muscle
ophthalmic artery
- branch off the internal carotid artery
- enters the orbit with the optic nerve through the optic canal
branches of ophthalmic artery + example
supply contents of the orbit and the eyelids
- central retinal artery
central retinal artery
nourishes the retina of the eyelid
superior ophthalmic vein
- formed by smaller veins that drain the orbit
- passes through the superior orbital fissure to drain into the cavernous sinus
cavernous sinus
- rich plexus of veins that surrond the internal carotid artery
inferior ophthalmic vein
usually joins the superior ophthalmic vein before draining into the cavernous sinus
what is pyomyositis of the extraocular muscles
- acute bacterial infection usually caused by staphylococcus aureus which is a bacterium frequently found in the upper respiratory tract and on the skin
- affects skeletal muscles and if found in the orbit of they eye is becomes this condition
symptoms of pyomyositis of the extraocular muscles
- pain
- swelling (bulging), redness in the eye as a immune response
- movement of eye restricted due to swelling of muscles and pain
- inflamed muscles can compress the optic nerve leading to vision impairments
what may occur with pyomyositis of the extraocular muscles depending on the location
central retinal artery occlusion, compressing blood supply to the eye
the ear
- contain organs of hearing and balance
- divided into 3 parts external ear, middle ear, inner ear
function of the middle ear
- air-containing space within the temporal bone of the skull which functions to transmit vibrations from the tympanic membrane (ear drum) to the internal ear
how many borders of the middle ear are there?
6
lateral border of the middle ear
- lateral membranous wall of the middle ear is formed by the tympanic membrane
medial border of the middle ear
the medial (labyrinthine) wall separates the middle ear from the inner ear
posterior wall of the middle ear
- thin bone separating the tympanic cavity from the mastoid air cells in the temporal bone
roof of the middle ear
- also known as tegmental wall
formed by a thin plate of the bone, the tegmen tympani, which separates the middle ear from the middle cranial fossa
floor of the middle ear
- also known as jugular wall
- thin bone separating the middle ear from the internal jugular vein below
anterior wall of the middle ear
- thin bone that separates the tympanic cavity from the internal carotid artery
- the upper anterior wall is incomplete because it has an opening for the Eustachian tube
what is the eustachian tube
- channel between the middle ear and nasopharynx
what does the eustachian tube do?
equalize the pressure on either side of the tympanic membrane allowing the tympanic membrane to vibrate properly for transmission of sound to the inner ear
nasopharnx
- the upper part of the pharynx that connects to the nasal cavity
eustachian tube dysfunction (ETD)
- usually a temporary caused by the inability to equalize the pressure in the middle ear
- may be experienced as dulled hearing and a feeling of pressure or fullness in the affected ear
symptoms of eustachian tube dysfunction (ETD)
- pain
- plugging
- muffing
- poor balance
causes of eustachian tube dysfunction (ETD)
- problems equalizing pressure
- tympanic membrane bulges out
- pressure pushes air bubble
- tube may not be open, tumoring scarring
- chemicals in middle ear (because the tube is always open)
- cannot clear the muscus (cilia problems)
what does the nasal septum form
the medial wall that separates the right and left nasal cavities
what forms the nasal septum
cartilage and bone
what does the anterior portion of the nasal septum contain
a rich anastomosis of arteries
irritation to arteries in anterior portion of nasal septum
irritation caused by allergens, bacteria, foreign objects can cause swelling restricting breathing
what supplies the nasal septum
- carotid arteries
- ophthalmic and maxillary arteries
-kisesselbachs plexus
carotid arteries
The internal and external carotid arteries ascend towards the nasal septum.
Ophthalmic and Maxillary Arteries of nose
The ophthalmic artery branches off the internal carotid artery and the maxillary artery branches off the
external carotid artery.
Kiesselbach’s plexus
Branches of the ophthalmic and maxillary arteries anastomose to form Kiesselbach’s plexus, a richly
vascularized area in the anterior portion of the nasal septum.
Sensory information from the nasal septum
carried by branches of the trigeminal nerve (C N V ),
whereas special sensory information (sense of smell) is carried by the olfactory nerve (C N I).
The anterosuperior part of the nasal septum is innervated by the
ophthalmic branch (V1) of the
trigeminal nerve
the rest of the nasal septum is innervated by the
maxillary branch (V2).
Irritation
caused by allergens, bacteria, or foreign objects can
irritate the nerves of the nasal septum and cause an “itchy” sensation upon repeated stimulation
Nasal polyps
- soft, painless, noncancerous growths that hang down like teardrops or grapes from the lining of the nasal cavity.
- common in adults
Causes of Nasal polyps
chronic inflammation (swelling) of the vascular supply in the walls of
the nasal cavity which may be associated with asthma, recurring infection, allergies, drug sensitivity, or
certain immune disorders.
Symptoms of nasal polyps
Small nasal polyps may not cause any symptoms. Larger growths or groups of nasal polyps can block
the nasal passages (congestion) leading to a loss of smell, breathing problems, and a post-nasal drip.
The oral cavity is bounded by
roof: palate
floor: a mucous
membrane covering the mylohyoid muscle.
lying on the floor of the oral cavity
is the tongue
The ninth cranial nerve
glossopharyngeal nerve
glossopharyngeal nerve
lingual branches that supply both general and special sensory innervation to the posterior ⅓ of the tongue.
trigeminal nerve oral cavity
mandibular division gives rise to the lingual nerve which supplies general sensory innervation to the anterior ⅔ of the tongue.
facial nerve- oral cavity
(taste) from the anterior ⅔ of the tongue is carried by the lingual nerve to the chorda tympani
chorda tympani
branch of the facial (VII) nerve.
the lingual artery wehre is it from
- external carotid artery ascends in the neck and gives rise to several branches including the maxillary and lingual artery
what does the liguinal artery supply
the tongue sublingual gland, and the floor of the mouth
what does the maxillary artery supply
supplies the upper jaw region and nose
Dysgeusia
distortion of the sense of taste.
about Dysgeusia
- distortion in the sense of taste is a symptom, and the diagnosis is usually complicated since the
sense of taste is tied to both the facial (chorda tympani) and glossopharyngeal nerves.
symptoms of Dysgeusia
distortion of taste, issues with swallowing and an impaired gag reflex, as these functions are controlled by the glossopharyngeal nerve.
nasal endoscopy
procedure to look at the nasal and sinus passages using a narrow tube instrument with a lighted magnifying lens or camera
what are muscles of mastication
4 paired muscles that attach to the mandible and are responsible for movements of the jaw
where are the pterygoid muscles located
on the inner surface of the mandible, deep to the temporalis and massester muscles
the lateral (external) pterygoid muscle
- fibers run horizontally to insert into the neck of the mandible as well as the capsule and articular disc of the temporomandibular joint (TMJ)
the medial (internal) pterygoid muscle
- fibers run obliquely downward and backwards to insert on to the medial surface of the mandible near its angle
actions of the muscles of mastication
chewing
muscles in elevation of chewing
elevation: temporalis, masseter, medial pterygoid
muscles in depression of chewing
Depression: primarily gravity and relaxation of the muscles
muscles in lateral (side to side) of chewing
medial and lateral pterygoids
muscles of protraction of chewing
lateral pterygoid
retraction muscles in chewing
temporalis
innervation of muscles of mastication
trigeminal nerve (C N V ) provides motor innervation to the muscles of mastication from the mandibular nerve (V3) branch.
what can cause lateral pyerygoid strain
overuse, or clenching of the jaw, perhaps when one is
under stress.
symptoms of lateral pterygoid strain
Chewing can become very painful if the tongue, or food, is pressed against the location of the muscle itself
- pain maxilla
- pain at TMJ
- TMJ dysfunction
what can lateral pterygoid strain result in
T M J dysfunction, due to its insertion on the neck of the mandible and capsule of the T M J
Pain radiating to the maxilla (jaw)
Pain will follow the pathway of the mandibular nerve (V3) innervating the lateral pterygoid.
Pain at T M J
Palpating the T M J itself may be painful due to strain at the muscle insertion. The muscle itself would
cause pain, aggravated by the act of chewing.
T M J Dysfunction
If the lateral pterygoid is strained, it can result in displacement of the articular disc of T M J , resulting in
an impairment of masticatory function. A clicking noise may be heard due to this resulting
misalignment at the joint.
what is the temporomandibular joint (T M J )
- synovial, modified hinge joint between the head (condyle) of the mandible, the mandibular fossa, and the articular tubercle of the temporal bone.
- Between the articular surfaces is a fibrocartilaginous articular disc.
movements of the TMJ
- during chewing it acts like a hinge between the head and the mandible and the articular disc
- during wide opening: mandible is depressed and pulled forward by the lateral pterygoid muscles, head of mandible and articular disc slide anteriorly on to the articular tubercles
- elevation : by the temporalis and masseter muscles and retraction by the temporalis
Temporomandibular joint (T M J ) syndrome
- can arise from problems with the
muscles of the jaw - T M J syndrome can also be caused by the joint itself becoming
compromised - typically due to excessive teeth grinding and jaw clenching which can result in misalignment of the articular disc, and potentially damage to the articular cartilage of the joint itself
symptoms of TMJ
- clicking
- Pain and tenderness in the jaw
- Pain in one or both temporomandibular joints
- Difficulty chewing
- Locking of the joint
maxillary artery for the supply of the muscles of mastication
terminal branch of the
external carotid artery
branch of the maxillary artery
middle meningeal artery
middle meningeal artery
enters the cranial cavity to supply much of the dura mater
epidural hematoma
- when branches of the middle meningeal artery run in the dura mater of the skull and a fracture in the skull can tear them and cause internal bleeding and increase intracranial pressure
causes of epidural hematoma.
are related to a blunt injury: a head injury from a motor
vehicle collision, physical assaults, or accidental falls. A break in the temporal bone of the skull may
result in this life-threatening condition.
symptoms of epidural hematoma.
initial loss of consciousness following trauma, a rapid neurological deterioration, and severe headaches due to the increase in intracranial pressure. Nearby intracranial structures may also be affected (e.g. cranial nerves). Hence, clinicians will often perform examinations that test for cranial nerve function.
what is the clicking sound from TMJ from
- displacement of the articular disc within the TMJ
- abnormal position relationship between the articular disc and the mandibular condyle, articular tubercle, and/or articular fossa
5 treatment options for TMJ syndrome
- physio to ease muscle pain
- medication to reduce pain and inflammation
- wearing a night guard or bit plate
- braces or other dental work to correct a misaligned bite
- surgery
how many cranial nerves are there
12
what does cranial nerve disorders affect
smell, taste, vision, sensation of the face, hearing, balance, speech, swallowing, muscles of the neck
CN VI
abducens nerve
CN VI abducens nerve
- lateral rectus and medial rectus must be activated to maintain a forward gaze and an imbalance would cause the eye to drift to one side
what innervates the lateral rectus of eye
CN VI abducens
CN V
trigeminal nerve
CN V- trigeminal nerve
carries general sensory information from the upper and lower jaw
- lower jaw is specifically the mandibular nerve
CN VII
facial nerve
CN VII - facial nerve
provides motor innervation to the muscles of the face / cuases expressions
CN XII
hypoglassal nerve
CN XII- hypoglassal nerve
- controls the muscles of the tongue
- if damaged moving tongue in and out as well as speaking or swallowing would be compromised
CN VIII
vestibulocochlear nerve
CN VIII- vestibulocochlear nerve
- transmits information regarding sound and equilibrium
- if damaged balance and hearing is impaired
what is the automatic nervous system divided into
parasympathic and sympathetic
parasympathetic ganglia (top to bottom in the figure)
- ciliary
- pterygopalatine
- submandibular
- otic ganglia
what do the parasympathic ganglia receive
preganglionic fibers from oculomotor (CN III), facial (CN VII), and glossopharyngeal nerves (IX)
otic ganglion
- small ganglion
- parasympathetic
- functionally associated with the glossopharyngeal nerve and innervates the parotid gland
the preganglionic parasympathetic fibers of the otic ganglion
- leave the medulla oblongata of the brainstem as the glossopharyngeal nerve (CN IX)
postganglionic parasympathetic fibers of the otic ganglion
- join the auriculotemporal nerve
auriculotemporal nerve
a branch of the mandibular division (V3) of the trigeminal nerve to innervate the parotid gland
what would happen if the auriculotemporal nerve was damaged
the parasympathetic nerve fibers to the partoid gland may switch course to a sympathetic response resulting in ‘gustarory sweating” or sweating in the anticipation of eating, instead of the normal salivary response by the parotid gland (freys syndrome)
freys syndrome
often results as a side effect of surgeries of or near the parotid gland
- diagnosed by having the individual eat and acidic lemon (should increase saliva) but if they have freys it will result in excessive sweating
more about the ophthalmic artery
- branch of the internal carotid artery
- supplies eyes and forehead
terminal branches of ophthalmic artery form?
extensive anastomoses with branches of the facial, maxillary, and superficial temporal arterteries all come from the external carotid artery
the superficial temporal artery
- arises from the external carotid artery in the parotid gland
- ascends the side of the face and crosses over the zygomatic arch to supply the skin and muscles of the temple and scalp and parotid gland
the facial artery
- enters the face by passing over the lower border of the mandible, running in a tortuous course towards the medial angle of the eye
what does the facial artery supply
- superficial structures of the skin and face such as muscles of the face and mastication
arteries that branch of the internal carotid artery that supply the face
- ophthalmic artery
arteries that branch of the external carotid artery that supply the face
- superficial temporal artery
- facial artery
superficial temporal artery (STA) aneursym
is the bulging or weakening of an artery wall
- brought on my traumatic injury such as a blunt force to the head
- symptoms headaches because it supplies temple and scalp
what is the main vein that drains the face
facial vein
facial vein
travels alongside the facial artery and empties into the internal jugular vein
how can infections spread through the facial vein
- veins of the face do not contain valves, allowing blood to flow in either directions
- thus the facial vein can be a conduit for infections to spread from the face intracranially to the cavernous sinuses
what nerves could be affect by infection in the cavernous sinus
CN IV, CN VI, CN-V3
what is the danger triangle
- CN IV, CN VI, CN- v3
lymph nodes of head and neck
superficial reing of nodes (collar nodes), superficial and deep cervical nodes
The collar nodes
the name originates from the location of the traditional collar at the junction of the head and the neck.
The superficial cervical nodes
found on the surface of the sternocleidomastoid (S C M ) muscle and are associated with the external jugular vein.
The deep cervical nodes:
found deep to S C M and are closely related to the internal jugular vein.
lymphatic system
- network of organs, vessels and over 600 lymph nodes
location of swollen lymph node
- doesnt always indicate a issue
- superficial lymph nodes such as those in head and neck signal the presense of common infections, autoimmune disorders, and even tumors
all lymphatic drainage of head and neck
empties into the deep cervical nodes
- deep cervical nodes continue to drain into the right lymphatic duct and thoracic duct draining the right and left sides of the head
