Anatomy Flashcards
which 2 vertebrae are different
C1- no vertebral body, occipital condyles
C2- bifid spinous process, odontoid process
know the foramens
inc jugular, ovale, rotundum, magnum
what passes through jugular foramen?
CN IX, X, XI
function and structure of external ear
collects sound waves and funnels them towards middle ear
auricle, EAM, tympanic membrane, pinna
innervation of external ear
helix- C2,C3
internal helix- CN V3
EAM- upper CN VII, lower CN X
ear lobe- C2, 3 (greater auricular nerve)
function of middle ear
conduct sounwaves in air towards fluid filled cavities of inner ear via bones- ossicles
structure of middle ear
temporal bone, ossicles (maleolus, incus, stapes), 2 synovial joints, 2 muscles
what is the posterior wall of middle ear
epitympanic recess
what are the skeletal muscles of middle ear
tensor tympani muscle: dampens malleus- CN V3
stapedius muscle: reduces vibrations of stapes on oval window- CN VII
what is CN VII’s journey
leaves at pons> IAM > ear > through temporal bone and then splits
what is the sensation aspect of CN VII
chorda tympani conveys taste from anterior 2/3rds of tongue
PS secretomotor function of CN VII
to submandibular, sublingual glands
somatic motor function of CN VII?
muscles of facial expression
the 6 branches of CN VII are…
temporal, zygomatic, buccal, mandibular, cervical
what is eustachian tube’s function?
equalises pressure between middle ear and nasopharynx. CN IX sensory nerve supply. may spread infection e.g.. tonsillitis > OM
glossopharyngeal nerve run down
leaves at oblongata > jugular foramen > enters parapharyngeal space and lies on stylopharngeal muscle
sensation of CN IX
middle ear, Eustachian tube, nano/oropharynx
somatic motor of CN IX
stylopharyngeus muscle, posterior 1/3rd of tongue
PS secretomotor function of CN IX
parotid gland
3 layers of inner ear
otic capsule, bony lap (perilymph- cochlea and vestibule), membranous labyrinth (ducts suspended in bony lab- endolymph)
cochlear apparatus
hair cells in organ of corti, cochlear ducts suspended by spiral ligaments
hair cells…
convey fluid motion into neural stimuli > travel along cochlear nerve (CN VIII branch)
vestibular apparatus…
semi-circular canal (detect angular movement), vestibule (trice and saccule- detect linear), hair cells
hair cells in VA
found at maculae of utricle and saccule and ampullae of SC ducts, covered in crystals (otoconia) > travel along vestibular nerve (CN VIII)
where does CN VIII (vestibulocohlear nerve) divide
once entered the ear
function of cochlear apparatus
hearing: TM vibrates > ossicles > stapes on oval window > pressure waves in perilymph > hair cells in cochlear generate AP > cochlear nerve (CN VIII)
function of vestibular apparatus
balance: hair cells stimulated by movement of andolymph
Internal acoustic meatus joins into where
lies in temporal bone and connects inner ear to posterior cranial fossa (CN VIII, CN VII< labyrinthine artery and vestibular ganglion)
nasal cavity
nose- 2 osseocartilaginous cavities- paranasal sinuses, lacrimal sac, nasopharynx
what are conchae and meatuses
conchae- make hair turbulent to allow more time for it to be cleaned
spaces above and below conchae are meatuses
what are the conchae and their corresponding meatuses
sphenoethmoidal recess superior nasal conchae superior meatus middle nasal conchae middle meatus inferior nasal conchae inferior meatus
name the arteries of the nose and the plexus that is susceptible to epistaxis
internal carotid artery > anterior ethmodial & posterior ethmoidal artery
external carotid > sphenopalatine artery, greater palatine artery
external carotid > lateral nasal artery, superior labial artery
kisselback’s plexus (in Little’s area)- made up of anterior, posterior ethmoidal cells, spehnopalatine and greater palatine artery, superior labial artery
how many paranasal sinuses are there and what is their function
4 pairs- reduce weight of skull & assist in vocal resonance
what drains into which sinuses
sphenoethmodial recess> sphenoid sinus
superior meatus> posterior ethmoidal air cells
middle meatus> ethmoidal air cells
nasolacrimal duct> inferior meatus
what are 2 regions of oral cavity
oral vestibule and oral cavity proper (from external surface of teeth to oropharynx)
tongue innervation
posterior 1/3rd= CN IX
anterior 1/3rd=
- CN VII= taste
- CN V3= general sensory
which is the only taste bud not for taste
filiform- touch, temp
what are the muscles of mastication
food in mouth: obicularis oris, buccinator
open: lateral pterygoid
close mouth: medial pterygoid, massteter, temporalis
arterial supply of head and neck
cranial cavity: internal carotid artery, vertebral artery
face: ICA & ECA
neck: ECA & subclavian artery
venous drainage of head and neck
follow arteries- all ultimately drain into internal jugular vein
T/F: parasympathetic nerve fibres synapse early and have long course to target organ
F: PS have ganglion close to target organ
S synapse at sympathetic chain and then have long journey to organ
sensory innervation has 1st, 2nd, 3rd order neurones with 2nd order Ns synapsing at thalamus
where do supra-glottic tumours drain into
cervical LNs, sub-glottic tumours drain to paratracheal nodes
what are the longitudinal muscles of pharynx
salpingopharyngeus, palatopharyngeus, stylopharyngeus
what are circular muscles of pharynx
constrictor muscles (sup, middle, inf)
what are the 3 protective mechanisms of the pharynx
Waldeyer’s tonsillar ring (pharyngeal, tubal, lingual, palatine), salivary glands (parotid, submand, sublingual), gag reflex
larynx is at the _____ spinal level
C4-C6, made up of 9 cartilage rings suspended from hyoid- mainly hyaline. also has arytenoid cartilage with conriculate cartilage. 2 joints (cricothyroid, cricoarytenoid)
innervation of larynx
above vocal folds > internal laryngeal nerve
mucosa below vocal folds> inferior laryngeal nerve
muscles- recurrent laryngeal nerve (except cricothryoid- superior LN)
where does inferior laryngeal nerve originate from
CN X> recurrent laryngeal nerve > inferior LN
what is main CN innervation of throat
CN X
sub glottal pressure causes air to cross vocal cords = vibration. laryngeal muscles (CN X) change way of speech
inc pitch= cricothyroid
dec pitch= thyroarytenoid
aDduction= arytenoid
aBduction= posterior cricoarytenoid
3 phases of swallowing- oral, pharyngeal, oesophageal… describe these
Oral: mastication (CN V3, CN VII, CN XII, CN X)
pharyngeal: bolus to oropharynx, hyolaryngeal elevation
oesophageal: once UOS opens bolus passes into stomach
what triggers gag reflex?
posterior 3rd of tongue, palatine tonsils, wall of oropharynx (CN IX)
innervation of laryngeal nerves
CN X- constrictors
CN IX and X- longitudinal muscles
what are the main components of the embryo head and neck that go on to form many structures
arches, pouches, clefts
how many arches are there and what they go on to form
1st arch- maxillary (maxilla, zygomatic bone), mandibular (mandible, incus/ malleus, temporal bone)
2nd- stapes, upper hyoid
3rd- lower hyoid
4th-6th- laryngeal cartilage
cranial nerves and arches
1st arch- CN V
2nd arch- CN VII
3rd arch- CN IX
4-6- CN X
what is a pathology from pharyngeal cleft malformation
cervical cyst
how does cleft lip form
malunion between inter maxillary process and palate shelves
