Session 9 Flashcards
What are the intrinsic muscles of the tongue?
- 4 paired muscles
- Lie entirely within tongue
- Run longitudinally, vertically and transversely
- Blend with extrinsic muscles
What is the innervation of the intrinsic muscles of the tongue?
- Hypoglossal nerve
- Motor innervation
What are the extrinsic muscles of the tongue?
- Genioglossus
- Hyoglossus
- Styloglossus
- Palatoglossus
What is the innervation of the extrinsic muscles of the tongue?
- Motor innervation from hypoglossal nerve
- Innervates genioglossus, hyoglossus, styloglossus
- Palatoglossus innervated by Vagus nerve
What is the action of the extrinsic muscles of the tongue?
- Protrusion (genioglossus, used to test hypoglossal nerve)
- Protraction
- Retraction
- Side-to-side move
- Anchor tongue
Outline the sensory innervation of the tongue
- Anterior 2/3 receives sensation from lingual nerve (trigeminal nerve) and taste from chorda tympani branch of facial nerve
- Posterior 1/3 receives sensation and taste from glossopharyngeal nerve
What are the salivary glands that secrete saliva into the oral cavity?
- Parotid glands
- Submandibular glands
- Sublingual glands
- Secrete saliva under influence of autonomic nervous system
Which duct is associated with the submandibular glands?
- Wharton duct
Which duct is associated with the parotid glands?
- Stensen duct
Outline the properties of the sublingual glands?
- Produce 3-5% of saliva
- Smallest and most diffuse of the salivary glands
- 8-20 excretory ducts per gland
Outline Sialolithiasis
- Salivary gland stones
- Most stones located in submandibular glands
- Due to dehydration or reduced salivary flow
- Most stones <1cm
What are the symptoms of sialolithiasis?
- Pain in gland
- Swelling
- Can fluctuate in realtion to eating
- Infection can occur due to stasis
How is sialolithiasis diagnosed?
- History
- X-ray
- Sialogram
What are the signs and symptoms of tonsilitis?
- Fever
- Sore throat
- Pain/difficulty swallowing
- Cervical lymph nodes (jugulodigastric)
- Bad breath
What causes tonsilitis?
- Viral causes most common
- Bacterial causes due to strep pyogenes
- Causes inflammation of palatine tonsils
Where are the palatine tonsils located?
- Between palatoglossal arch and palatopharyngeal arch
- Uvula central
What are the causes of peritonsillar abscesses?
- Follow on from untreated or partially treated tonsillitis
- Or can arise on their own due to aerobic or anaerobic bacteria
What are the symptoms of peritonsillar abscesses?
- Severe throat pain
- Bad breath
- Drooling
- Difficulty opening mouth
What are the boundaries of the nasopharynx?
- Base of skull to upper border of soft palate
- Posterior border is C1 and C2
- Anterior border is nasal cavity
What is found within the nasopharynx?
- Orifice of eustachian tube
- Pharyngeal tonsil
Where is the pharynx located?
- Base of skull
- Extends to C6
- Forms part of digestive tract
- Superior part lies posterior to nasal and oral cavities
What are the boundaries of the oropharynx?
- Soft palate to epiglottis
- Anterior border is oral cavity
- Posterior border is C2 and C3
What is found within the oropharynx?
- Palatine tonsils found between palatopharyngeal arch and palatoglossal arch
What are the boundaries of the laryngopharynx?
- Oropharynx to oesophagus
- Epiglottis to cricoid cartilage
- Anterior border is larynx
- Posterior border is C4, C5, C6
What are the muscles of the pharynx?
- 3x longitudinal muscles
- Stylopharyngeus
- Palatopharyngeus
- Salpingopharyngeus
What is the action of the pharyngeal muscles?
- Elevate pharynx and larynx during swallowing
- This widens aperture for food to go down oesophagus
- Reduces distance food has to travel to enter oesophagus
Outline the origin and insertion for Stylopharyngeus
- Styloid process - posterior border of thyroid cartilage
- Glossopharyngeal nerve
Outline the origin and insertion for palatopharyngeus
- Hard palate - posterior border to thyroid cartilage
- Pharyngeal branch of Vagus nerve
Outline the origin and insertion for salpingopharyngeus
- Cartilaginous part of Eustachian tube
- Merges with palatopharyngeus
- Pharyngeal branch of vagus nerve
What are the pharyngeal constrictors?
- 3x circular muscles
- Superior pharyngeal constrictor
- Middle pharyngeal constrictor
- Inferior pharyngeal constrictor (thyropharyngeal and cricopharyngeal)
What is the origin and insertion of the superior pharyngeal constrictor?
- Origin is pterygomandibular raphe
- Vagus nerve
What is the origin and insertion of the middle pharyngeal constrictor?
- Origin is hyoid bone
- Vagus nerve
What is the origin and insertion of the inferior pharyngeal constrictor?
- Thyropharyngeal originates at thyroid cartilage
- Cricopharyngeal originates ay cricoid cartilage
- Vagus nerve
What is a pharyngeal pouch?
- A posteromedial (false) diverticulum
- Arises in weakness between 2 parts of inferior constrictor
What causes pharyngeal pouch?
- Failure of upper oesophageal sphincter to relax
- Abnormal timing of swallowing
- Higher pressure in laryngopharynx
- Weakness in inferior constrictor muscle produces outpouching
- Symptoms related to food material collecting in pouch or disruption of swallow
What are the symptoms of pharyngeal pouch?
- Bad breath
- Regurgitation of food
- Occasional choking on fluids
- General difficulty swallowing
Where is the pharyngeal plexus located?
- Mainly on surface of middle constrictor muscle
- Vagus, glossopharyngeal and cervical sympathetic nerves
What is the motor innervation of the pharyngeal plexus?
- CN X innervates all muscles
- Except stylopharyngeus (CN IX)
What is the sensory innervation of the pharyngeal plexus?
- Nasopharynx (maxillary nerve CN Vb)
- Oropharynx (glossopharyngeal nerve CN IX)
- Laryngopharynx (vagus nerve CN X)
Outline the oral stage of swallowing
- Voluntary
- Preparatory phase makes bolus
- Transit phase - bolus compressed against palate and pushed into oropharynx by tongue and soft palate
- Hypoglossal nerve
Outline the pharyngeal stage of swallowing
- Involuntary
- Tongue positioned against hard palate so food cannot re-enter mouth (CNXII)
- Soft palate elevated sealing off nasopharynx (CN Vc and CN X)
- Eustachian tube opened
- Suprahyoid and longitudinal muscles shorten - pharynx widens and shortens to receive bolus
- Larynx elevated and sealed off by vocal cords
Outline the pharyngeal stage of swallowing
- Involuntary
- Tongue positioned against hard palate so food cannot re-enter mouth
- Soft palate elevated sealing off nasopharynx
- Eustachian tube opened
- Suprahyoid and longitudinal muscles shorten - pharynx widens and shortens to receive bolus
- Larynx elevated and sealed off by vocal cords
- Epiglottis closes over larynx
- Bolus moves through pharynx by contraction of constrictors
- Relaxation of UOS
Outline the oesophageal stage of swallowing
- Involuntary
- Upper striated muscle of oesophagus
- Lower smooth muscle
What might cause dysphagia?
- Stroke
- Oesophageal cancer
- ## Blockage
What are the signs and symptoms of dysphagia?
- Coughing and choking
- Sialorrhoea (drooling)
- Recurrent pneumonia
- Change in voice/speech (wet voice)
- Nasal regurgitation
What cranial nerve problems can affect the pharynx?
- IX, X
- Absent gag
- Uvula deviated away from lesion
- Dysphagia
- Taste impairment
- Loss of sensation in oropharynx
- Caused by medullary infarct, jugular foramen issue
What are the functions of the nasal cavity?
- Olfaction
- Filtering and humidifying inspired air
- Drainage of secretions from paranasal sinuses and nasolacrimal ducts
Outline the structure of the external nose
- Predominantly cartilaginous
- Frontal processes of maxillae and nasal bones form root
What can injuries to the nose cause?
- Septal haematomas
- Septal deviations
- Nasal bone fractures
Outline the structure of the nasal cavity?
- Roof
- Lateral wall
- Medial wall
- Floor
- Nostrils anteriorly
- Chonae posteriorly
What are the regions of the nasal cavity?
- Vestibule
- Respiratory region
- Olfactory region
What are the bones that contribute to the nasal cavity?
- Roof: frontal bone, ethmoid bone, sphenoid bone, nasal bones
- Floor: palatine bone, maxilla
What is important clinically about the nasal vestibule?
- Route through which surgeons operate on pituitary gland
What is the function of the concha?
- Slow down air flow
- Increase surface area
- For warming and humidification
What are the meatuses?
- Superior, middle, inferior
- Formed from lateral wall of nasal cavity
- Drainage
- Connection with paranasal air sinuses and nasolacrimal duct
What is a septal haematoma?
- Trauma to cartilage causes the perichondrium to be stripped off
- Can lead to avascular necrosis
- Saddle nose deformity
How common are nasal bone fractures?
- Account for 50% of all facial fractures
How does a nasal bone fracture present?
- Lots of swelling seen
- Commonly see epistaxis
How do we treat nasal bone fracture?
- X-rays not generally required
- Follow up in several days in outpatient clinic once swelling has settled
What can nasal bone fracture result in?
- Rare complications include CSF leak and anosmia
- Can lead to a deviated septum and blocked nose
What is the blood supply to the nasal cavity like?
- Rich blood supply
- Anterior and posterior ethmoidal arteries (branches of ophthalmic artery) supply medial wall
- Sphenopalatine artery and greater petrosal artery (branches of maxillary artery) supply lateral wall
Why does the nose need such a rich blood supply?
- Allows it to perform two of its functions:
1. Humidification
2. Warming incoming air
Which blood vessel is the ophthalmic artery a branch of?
- Internal carotid artery
Which blood vessel is the maxillary artery a branch off?
- External carotid artery
What is the nervous supply to the nasal cavity?
- Trigeminal nerve - ophthalmic branch and maxillary branch
What are nasal polyps?
- Benign swellings of the nasal mucosa
What is the epidemiology of nasal polyps?
- Typically seen in those >40 years old
- Affects more males than females
- Normally bilateral
What are the symptoms of nasal polyps?
- Nasal congestions
- Rhinorrhoea
- Hypo- or anosmia
- Snoring
- Post nasal drip
What are the symptoms of rhinitis?
- Nasal congestion
- Rhinorrhoea
- Sneezing
- Post-nasal drip
- Nasal irritation
What are the paranasal air sinuses?
- Air filled spaces that are extensions of the nasal cavity
- Lined with respiratory mucosa (ciliated and secrete mucus)
What can infection in the nasal cavity lead to?
- Sinusitis
- Maxillary sinus most commonly affected
What are the various functions of the paranasal air sinuses?
- Humidify and warn inspired air
- Reduce weight of the skull
Where do the paranasal air sinuses drain to?
- Drain into the nasal cavity via small channels (ostia) into a meatus
What does the middle meatus drain?
- Frontal sinus
- Maxillary sinus
- Anterior ethmoid sinus
What does the middle meatus drain?
- Frontal sinus
- Maxillary sinus
- Anterior ethmoid sinus
What does the inferior meatus drain?
- Nasolacrimal duct
What does the superior meatus drain?
- Sphenoid sinus
What is the general sensory innervation of the sinuses?
- Va supplies frontal, ethmoidal and sphenoid sinuses
- Vb supplies the maxillary sinuses
What usually causes sinusitis?
- Viral upper respiratory tract infection
- Spreads to sinuses
What is the pathophysiology of sinusitis?
- Inflammation of respiratory mucosa causes swelling, reduced cilia movement and increased secretions
- Ostia can become blocked
- Fluid builds up in sinus
- Can develop a secondary bacterial infection
How is sinusitis diagnosed?
- Recent URTI
- Blocked nose and rhinorrhoea +/- green/yellow discharge
- Pyrexia
- Headache/facial pain (in area of affected sinus) - worse on leaning forward
How is sinusitis managed?
- Conservatively
What makes acute bacterial sinusitis more likely?
- Symptoms particularly severe at onset
- Symptoms >10 days without improvement but < 4 weeks
- Symptoms that worsen after an initial improvement (suggesting secondary bacterial infection)
Which organisms cause bacterial sinusitis?
- Streptococcus pneumonia
- Haemophilus influenzae
- Moraxella catarrhalis are most common bacteria
How can most nosebleeds be stopped?
- Pinching in front of (not on) the bony bridge of the nose and holding it for 15-20 minutes
Which vessels coalesce at Kiesselbach’s area?
- Greater palatine
- Sphenopalatine
- Superior labial arteries
- Anterior and posterior ethmoidal arteries
What is the site of origin of most nosebleeds?
- The cartilaginous part of the septum known as Little’s area
Why can bleeds from the sphenopalatine artery be particularly problematic?
- Blood in this vessel tends to be at higher pressure
- And as it is posteriorly located in the nasal cavity, it is harder to reach to stop the bleed
What can cause nosebleeds?
- Spontaneous
- Or with very minor trauma to the nose
- May be due to underlying systemic causes e.g. abnormal coagulation and connective tissue disorders
Who is most commonly affected by nosebleeds?
- Very young people (2-10 years old)
- Old people (50-60 years old)
Why are serious nosebleeds so dangerous?
- Significant blood loss
- Rarely can cause death
How is epistaxis managed?
- Applying simple compression
- Leaning forward
- If these steps fail, attempts should be made to cauterise a visible bleeding point using silver nitrate
What do we do if bleeding is significant or the bleeding point cannot be identified?
- May mean that cauterisation is difficult
- Anterior packing with nasal tampons can be used instead
- These packs expand within the nasal cavity and tamponade the area of bleeding
What do we do if bleeding is significant or the bleeding point cannot be identified?
- May mean that cauterisation is difficult
- Anterior packing with nasal tampons can be used instead
- These packs expand within the nasal cavity and tamponade the area of bleeding
What do we do if anterior packing of the nasal cavity fails?
- Posterior packing
- Surgical intervention as a last resort e.g. embolization, ligation of blood vessels
What needs to be monitored in severe epistaxis?
- ABCDE approach
- Closely monitor patient
- Blood tests to check Hb levels and clotting
- Any underlying systemic causes for the bleeding should be sought and treated e.g. coagulopathies
