Session 9 Flashcards
Tongue muscles
Parotid gland anatomy
Features of salivary gland stones
Sialolithiasis
- Most stones are located in the submandibular glands
- Dehydration, reduced salivary flow
- Most stones less than 1cm diameter
Symptoms of salivary gland stones
Eating stimulates
Pain in gland, swelling, infection
Diagnosis of salivary gland stones
History, X ray, sialogram
Features of tonsillitis
Inflammation of palatine tonsils
Fever, sore throat, dysphagia, cervical lymph nodes, bad breath
Viral causes most common
Bacterial up to 40% of cases, e.g Strep pyogenes
Features of peritonsilar abscess
Severe throat pain, fever, bad breath, drooling, difficulty opening mouth
Can follow on from untreated or partially treated tonsillitis
Can arise on its own from aerobic and anaerobic bacteria
Nerve innervation of pharynx plexus
Pharyngeal plexus
Located mainly on surface of middle constrictor muscle
Vagus, glossopharyngeal, and cervical sympathetic nerves
Nerve innervation of pharynx- motor
CN X innervates all muscles
Except stylopharyngeus (glossopharyngeal nerve CN 9)
Nerve innervation of pharynx- sensory
Nasopharynx (maxillary nerve CN Vb)
Oropharynx (glossopharyngeal nerve CN 9)
Laryngopharynx (vagus nerve CN X)
Submandibular gland duct
Wharton duct
Parotid gland duct
Stensens duct
IX and X Cranial nerve problems in mouth area
Absent gag, deviated uvula (away from lesion)
Dysphagia, taste impairment posterior tongue, loss of oropharynx sensation
Caused by medullary infarct, jugular foramen issue (fracture)
XII cranial nerve problems in mouth area
Wasted tongue
Deviated tongue when stuck out - damage to nerve itself (point to side of lesion)
Muscle wasting
Fasiculations
Oral cavity consists of
2 lateral walls, a floor and a roof
Lateral walls- buccinators
Roof- Hard and soft palate
Floor- 2 mylohyoid muscles, tongue
The oral cavity begins anteriorly at the
Oral fissure- bounded by the lips
Oral cavity extends posteriorly to the
Oropharyngeal isthmus (arch formed by soft palate above and upper surface of tongue below)
Sides of the Oropharyngeal isthmus are formed by the
Anterior and posterior pillars of the fauces
Formed by palatoglossus (anterior) and palatopharyngeal (posterior) muscles
What does contraction of palatoglossus and palatopharyngeal muscles cause
Pulls soft palate down towards back of tongue, closes Oropharyngeal isthmus, ensures food remains in oral cavity
What lies between the anterior and posterior pillars of fauces
Tonsillar fossa, within this the palatine tonsil, making up Waldeyer’s ring
Palatine tonsil is often easily visible and readily noticed when swollen due to inflammation in
Tonsillitis
Broadly describe the tongue
Entirely muscular tissue covered in mucous membrane (squamous epithelium)
Intrinsic and extrinsic muscles
Describe the intrinsic muscles of the tongue
4
Lie entirely within the tongue and run longitudinally, vertically and transversely
Alter shape of tongue
Blend with extrinsic muscles as have no attachment to bone
Describe the extrinsic muscles of tongue
Change position of tongue
Protrusion, retraction and side-to-side
Anchor tongue to surrounding structures
What do the extrinsic muscles anchor the tongue to
Hyoid and mandible below
Styloid process and soft palate above
Most important of four extrinsic muscles
Genioglossus- one on each half of tongue
Contraction protrudes the tongue (action for determining hypoglossal nerve function)
Hypoglossal nerve innervates what part of tongue
All muscles of tongue except 1- the palatoglossus (forms shape of anterior arch and soft palate, vagus nerve)
Why does the tongue receive afferent innervation from a number of cranial nerves
Because of its different embryological origins from several pharyngeal arches
Innervation of the tongue posterior 1/3
Glossopharyngeal
Motor innervation of tongue
Hypoglossal except Palatoglossus (vagus)
Sensory innervation of anterior 2/3 tongue
Lingual branch of V3 from trigeminal
Taste innervation of anterior 2/3 tongue
Chorda tympani branch of Facial 7, carried by lingual branch
Innervation of tongue overview
Dorsal surface of tongue is covered in
Papillae
Location for sensory receptors for tastes ie taste buds
Hypoglossal nerve lesion sign and vagus nerve lesion sign
Hypoglossal = tongue deviation
vagus nerve = uvula deviation
Describe the pharynx
Muscular tube that continues as the oesophagus, arising from base of skull extending down to level of C6
Narrowest part of oesophagus
Inferior end where it becomes continuous with the oesophagus
Posterior wall of pharynx is covered with and lies against
Buccopharyngeal fascia,
lies against prevertebral layer of deep cervical fascia (where we find retropharyngeal space)
Order of 3 parts of pharynx
Nasopharynx
Oropharynx
Laryngopharynx
Where does the Nasopharynx lie
Superior to soft palate
Posterior extension of nasal cavities, open into it through nasal apertures/choanae
C1 vertebrae lies posteriorly
What lies within the Nasopharynx
Orifice of the Pharyngotympanic/Eustachian tube
Collection of lymphoid tissue- pharyngeal tonsil/adenoids
Where is oropharynx
Level of soft palate to superior border of epiglottis
C2 and C3 vertebral bodies lie posteriorly
Palatine tonsils lie on either side in interval between palatoglossal and palatopharyngeal arches
Where is laryngopharynx
Epiglottis to the oesophagus, level of inferior border of cricoid cartilage
Vertebral bodies of C3-6 lie posteriorly
Piriform fossa on each side of laryngeal inlet
Walls of the pharynx
Externally- circular superior, middle and inferior constrictors
Vagus nerve
Posterior common insertion point of pharyngeal constrictors
Common midline tendinous insertion called the pharyngeal raphe
Inferior pharyngeal constrictor consists of
2 muscle bellies, thyropharyngeus and cricopharyngeus
Small area of weakness known as Killian’s dehiscence between the muscle belly components
Clinical relevance of Killian’s dehiscence
In coordination of pharynx
Pressure rises
Part of pharyngeal mucosa herniated through Killian’s dehiscence, forming pharyngeal pouch or diverticulum
Internally, the wall of the pharynx consists of
3 longitudinal muscles that act to shorten and widen the pharynx, during swallowing and speaking
Majority of the nerve supply to the pharynx is derived from the
Pharyngeal plexus of nerves - formed by branches of the vagus, glossopharyngeal and sympathetic branches from the superior cervical ganglion
Vagus nerve supplies
All muscles of the pharynx and soft palate except the stylopharyngeus (supplied by CN 9)
Sensory supply to pharynx
Nasopharynx- maxillary branch of trigeminal CN Vb
Oropharynx and Pharyngotympanic tube- glossopharyngeal nerve CN IX
Laryngopharynx- vagus nerve CN X
What is Waldeyer’s ring
Lymphoid ring formed around Nasopharynx and oropharynx
Pharyngeal tonsils, palatine tonsils and lingual tonsils
Features of pharyngeal tonsils/adenoids
Prominent in children
Undergo atrophy after puberty
Adenoiditis (chronic inflammation) may obstruct passage of air causing mouth breathing and nasal tone
Can block exit of the Pharyngotympanic tube and lead to middle ear infections (acute otitis media) or otitis media with effusion
Pharyngotympanic tube provides a
Potential route for infection in the pharynx to spread to the middle ear
Common for URTI to be complicated by middle ear infections
Tonsillitis may require
Tonsillectomy from tonsillar bed
May result in profuse bleeding from the rich blood supply to the tonsil- via tonsillar branch of facial artery
What is clinical relevance of piriform fossa
Potential site for foreign bodies entering pharynx to become lodged
Site for pharyngeal cancers
