Module 07 - Head and Neck Flashcards
Case Presentation:
62 yo male recently moved to warmer climate and has undergone facial reconstruction surgery, hair transplant and was fitted for dentures all completed 2 weeks ago.
He’s experiencing facial pain on his right cheek (beneath his eye down to mandible). and on and off near the top of his forehead. The cheek area is slightly swollen Has been having difficulty eating and drinking and has been brushing his hair despite surgeon telling him not to.
Targeted regions
4 DDX
Most like diagnosis + treatment
1- Hair follicles, scalp, facial vasculature, innervation, and musculature, oral cavity and proximal anatomical structures
2-
a) Postoperative complications from his hair transplant. Can cause nerve damage (numbness/lack of sensation, bleeding) or infections
b) Salivary gland stones can be caused by trauma to the salivary gland and cause swelling of the gland (and therefore cheek), pain near the duct, especially after eating, and difficulty opening mouth
c) Buccinator muscle strain causing deep pain in the cheek and/or during movements
d) trigeminal neuralgia is a chronic pain condition from trigeminal nerve impairment. brief periods of stabbing or shooting pain in teeth, jaw, gum and sometimes forehead
Trigeminal neuralgia and salivary gland stones are both reasonable diagnosis - Need x ray to confirm salivary gland stone
Small stone: sucking on a lemon or sour candies can stimulate saliva flow and help the stone pass naturally. Or massaging the cheeks to push stone out
Large stone: surgery; small incision is made in oral cavity to remove stone
What are the layers of the scalp?
mnemonic SCALP Skin (dense) Connective tissue Aponeurosis Loose connective Tissue Periosteum
What structures can you find in the skin layer of the scalp?
epidermal appendages such as hair follicles and sebaceous glands
What structures can you find in the dense connective tissue layer of the scalp?
Highly vascularized and innervated layer, also contains hair follicle
What layer of the scalp must be penetrated for a scalp laceration to bleed profusely?
dense connective tissue layer
describe the anatomy of the aponeurosis layer and its function?
Thin, broad, tendon-like sheet covering dome of skull.
Serves as an intermediate tendon between occipitalis muscle posteriorly and frontalis muscle anteriorly
What are the 2 muscles that move the scalp?
occipitalis and frontalis
What is the danger area of the scalp and why?
Loose connective tissue layer, because infections can easily spread within it and enter cranial cavity
Which layer provides an easy plane of separation between the upper 3 layers and the pericranium (external periosteum)?
Loose connective tissue layer
Describe the anatomy of the periosteum and its function
Very thin layer of connective tissue covering the bones of the skull
Protects the skull and provides nutrients to the bone
What are the 3 salivary glands?
parotid gland
sublingual gland
submandibular gland
How much saliva do the salivary glands produce per day?
0.5 to 2.0 liters
What’s the duct of the parotid gland and where is it anatomically?
Stensen’s duct
Superficial to the masseter muscle, piercing the buccinator muscle to open into the oral cavity opposite the second upper molar tooth
What is the result of the contraction of the buccinator?
pulls the cheek tightly against the teeth preventing food from collecting between the teeth and the gums during mastication. Works in concert with the tongue to keep the food between the molars
Which nerves provide both sensory and motor innervation to the face?
CNVII Facial Nerve
CN V Trigeminal Nerve
What are the 5 branches of the facial nerve?
1- Temporal 2- Zygomatic 3- Marginal mandibular 4- Cervical 5- Buccal
Which branch of what nerve innervate the buccinator?
Buccal branch of Facial nerve
What are the 3 division of the trigeminal nerve (CN V)?
V1 - Ophthalmic
V2 - Maxillary
V3 - Mandibular
What is the function of the mandibular division of CN V?
Sensory supply skin of lower lip, lower face, temporal region, and upper part of external ear.
Motor information to the muscles of mastication
What is the function of the maxillary division of CN V?
sensory: skin of the lateral sides of the nose, lower eyelid, cheek, temporal region, and upper lip
What is the function of the ophthalmic division of CN V?
Sensory: skin of forehead, upper eyelid and midline of the nose
Case Presentation
Patient suffers from seasonal allergies, but this year it seems worse than unusual. Itchy, red watery eyes, itchy ears, runny nose, itchy throat, post-nasal drip and loss of taste and smell.
Key structures
4 DDX
Most likely diagnosis + treatment
1- Eye, ear, nose, oral cavity
2
a) Pyomyositis of the extrocular muscles; acute bacterial infection usually caused by Staph. Causes pain, swelling, redness in the eye as a result of the immune response . movement of the eye can also be restricted. can sometims lead to vision impairment and central renal artery occlusion (due to swelling)
b) eustachian tube dysfunction: inability to equalize pressure, causes dulled hearing and a feeling of pressure or fullness in affected ear
c) nasal polyps, soft painless noncancerous growths that hang down like teardrops, caused by chronic inflammation, they can block nasal passageways leading to loss of smell, breathing problems and post-nasal drip
d) dysgeusia, distortion of sense of taste,
Nasal polyps confirmed with endoscopy
treatment:
medication to reduce blood to maxillary and ophthalmic artery to reduce swelling
surgery to remove the polyps. Long term management is reducing inflammation
What are the 2 axis in the movement of the eye?
Horizontal and Vertical
What are the muscles of the horizontal axis or the eye?
Superior rectus
Inferior rectus
inferior oblique muscle
superior oblique muscle
What muscles facilitate elevation of the eyeball with the pupil in the midline?
superior rectus and inferior oblique muscle
What muscles facilitate depression of the eyeball with the pupil in the midline?
inferior rectus and superior oblique muscles
What are the muscles of the vertical axis?
lateral rectus muscle
medial rectus muscle
Which muscle allows for the abduction of the eyeball?
lateral rectus muscle
Which muscle allows for the adduction of the eyeball?
medial rectus muscle
Which artery supplies the contents of the orbit and eyelids?
ophthalmic artery
Where does the ophthalmic originate?
internal carotid artery
How does the ophthalmic artery enter the orbit?
Through the optic canal with the optic nerve
Which nerve provides special sensory information from the eyeball?
optic nerve
Which veins are responsible for venous drainage of the orbit?
Superior ophthalmic vein
Inferior ophthalmic vein
Where does the superior and inferior ophthalmic veins drain into?
cavernous sinus
What are the borders of the middle ear?
lateral: tympanic membrane
medial: medial (labyrinthine) wall
posterior: posterior wall, thin bone separating tympanic cavity and mastoid aircells in temporal bone
anterior: carotid wall, thin bone that separates tympanic cavity from internal carotid artery (incomplete because eustachian tube)
Floor: jugular wall, thin bone separating middle ear from internal jugular vein
roof: tegmental wall is made by thin plate of bone; the tegmen tympani
What is eustachian tube?
channel between the middle ear and nasopharynx. Helps equalize the pressure on either side of the tympanic membrane, allowing it to vibrate properly
What are the components of the nasal septum?
vertical plate of ethmoid bone superiorly, vomer bone inferiorly, and septal cartilage anteriorly
What is the nasal septum?
common medial wall separating right and left nasal cavities - important supporting structure of the nasal cavity
What are the components of the arterial supplys of nasal septum?
carotid arteries, ophthalmic and maxillary arteries, kiesselbach’s plexus
describe the arterial supply of the nasal septum
internal and external carotid arteries ascend towards nasal septum. Ophthalmic arteries branch off internal carotid artery and maxillary artery branches off the external carotid artery. Branches of the ophthalmic and maxillary arteries anastomose to form the kiesselbach’s plexus, a richly vascularizes area in the anterior portion of the nasal septum
What are the nerves that innervate the nasal septum and what types of innervation?
Trigeminal nerve (CN V) - sensory information Ophthalmic division innervate anterosuperior part, maxillary division innervates the rest
Olfactory nerve (CN I) - special sensory information (smell)
What is the roof of the mouth ?
Hard palate made of bone
Soft palate, posteriorly, made of soft tissues
What is the floor of the mouth ?
Mylohyoid myscle
What are the 3 nerves that innervate the tongue and what does each nerve innervate + type of innervation?
Glossopharyngeal nerve (CN IX) has lingual branches that supply general and special sensory (taste) to the posterior 1/3 of the tongue
Trigeminal nerve (CN V) mandibular branch further gives rise to the lingual nerve. General sensory innervation to the ANTERIOR 2/3 of the tongue
Facial Nerve (CN VII) through the chorda tympani (nerve) special sensory (taste) to the ANTERIOR 2/3 of the tongue. Chorda tympanie joins the lingual nerve
What common surgical clinical application do oral surgeons need to keep in mind the location of the lingual nerve?
Extraction of the third molar (wisdom teeth)
Describe the arterial supplys of the tongue
external carotid artery ascends in the neck and gives rise to several branches including the maxillary and lingua artery
lingual artery supplies the tongue, sunlingual gland, and the floor of the mouth
Maxillary artery supplies the upper jaw region and nose
What are the 2 pterygoid muscles of mastication?
medial pterygoid
Lateral petrygoid
What are the 4 paired muscles of mastication?
Temporalis
Masseter
Lateral pterygoid
Medial pterygoid
Describe the lateral (external) pterygoid muscle
Fibres run horizontally to insert into the neck of the mandible as well as the capsule and articular disc of the temporomandibular joint
describe the medial (internal) pterygoid muscle
Fibres run obliquely downwards and backwards to insert on to the medial surface of the mandible near its angle
What muscles participate in the elevation of the mandible?
Temporalis, Masseter, medial pterygoid
What muscles participate in the depression of the jaw?
Mostly gravity, and relaxation of the muscles. not an active process
What muscles participate in lateral chewing?
medial and lateral pterygoids
What muscle participates in protraction of the mandible?
lateral pterygoid
What muscle participates in the retraction of the mandible?
temporalis
What nerve innervates the muscle of mastication?
trigeminal nerve CN V through the mandibular branch
Describe the temporomandibular joint
Synovial, modified hinge joint between the head (condyle) of the mandible, the mandibular fossa, and the articular tubercles of the temporal bone. Between the articular surfaces is a fibrocartilaginous articular disc
Describe the arterial supply of the masticatory apparatus
Maxillary artery supplies the muscles of mastication (terminal branch of external carotid artery)
An important branch of the maxillary artery is the Middle Meningeal artery, which enters the cranial cavity to supply much of the dura matter
Describe the anatomy of the pharynx
Fibromuscular tube that extaens from the base of the skull to the upper esophageal sphincter (UES). Fibromuscular walls of the phraync are formed by 3 pairs of constrictor muscles
What are the 3 muscles of the pharynx
Superior, middle, inferior constrictors
What are the 3 muscles of the pharynx
Superior, middle, inferior constrictors
Which muscle participates in the formation of the upper esophageal sphincter (UES)
Inferior constrictor
Which structure prevents the reflux of food into the airway and prevents air from entering the digestive tract?
Upper esophageal sphincter
What structures unite the respiratory and digestive systems
- pharynx
- oral cavity
What are the 3 sections of the pharynx?
Nasopharynx
Oropharynx
laryngopharynx
Which structure allow the nasopharynx to communicate with the nasal cavities?
Choanae
Where are the lower openings of the eustachian tubes located?
Lateral walls of the nasopharynx
What is the pharyngeal tonsil?
Collection of lymphatic tissue of the roof of the nasopharynx
What structure links the nasopharynx to the oropharynx?
Pharyngeal isthmus
The elevation of the soft palate closes which structure?
pharyngeal isthmus
What can the enlargement of the pharyngeal tonsil cause?
Almost completely fill the nasopharynx and cause difficulty in nasal breathing as well as obstruction of the eustachian tubes, with resultant loss of hearing
If you were going to do a nasopharyngeal swab test for covid 19, describe the path of the cotton swab
Swab enters the nasal cavity through the nasal vestibule and travels through the nasal cavity parallel to the nasa conchae. At the posterior end of the conchae, the swab travels across the choana and then past the openings of the eustachian tube. The collection point is in the nasopharynx inferior to the pharyngeal tonsil
What does the swelling of the palatine tonsils cause?
Typically due to an infection, can affect the glossopharyngeal nerve (CNXII_ and refer pain to the middle ear which is felt as earache
The oropharyngeal isthmus connects which structures?
the oral cavity and the oropharynx
What are the 2 folds of mucous membranes on each side of the oropharynx called?
palatoglossal arch
palatopharyngeal arch
describe the anatomy of the palatoglossal and palatopharyngeal arches
they consist of 2 folds of mucous membranes supported by underlying muscles
the palatopharyngeal is located posteriorly and medially to the palatoglossal arch
describe the location and anatomy of the palatine tonsils
Lymphatic tissue locatel between the arches (palatoglossal/palatopharyngeal arches). Its medial surface projects into the oropharynx and its lateral surface lies against the superior constrictor muscle
describe the location of the laryngopharynx
extends from the oropharynx to the esophagus
What and where is the laryngeal inlet?
Opening of the pharynx into the larynx, located anteriorly in the laryngopharynx
What and where are the piriform recesses?
On each side of the laryngeal inlet, they form channels that direct food from the oral cavity to either side of the raised laryngeal inlet toward the esophagus
Where is a common site where swallowed objects such as fish bones can get lodged?
Piriform recesses, and usually needs to be removed by a physician
