Sinus, Nasal, Ear, Orbit Flashcards
what are the 3 external nasal muscles?
- procerus
- nasalis - 2 parts
- levator labii superioris alaeque nasi
- all innervated by facial n.
- supplied by facial a. and ophthalmic a.
what are all of the components of the external nose?
- nasal bones
- lateral cartilage
- septal cartilage
- alar cartilage
- fibroareolar tissue
- external nares
what features make up the lateral walls of the nasal cavity?
- superior, middle, and inferior nasal conchae
- superior, middle, and inferior nasal meatuses
major sources of blood for the lateral nasal cavity
- ICA
- ophthalmic a.
- ethmoidal aa.
- ophthalmic a.
- ECA
- facial a.
- maxillary a.
- sphenopalatine
- lateral posterior nasal aa.
- sphenopalatine
major sources of blood for the nasal septum
- ICA
- ophthalmic – ethmoidal arteries – anterior septal branches
- ECA
- maxillary – sphenopalatine – posterior septal branches
- facial – septal branch of superior labial artery
innervation of the nasal cavity
- V-1 – anterior nasal septum and cavity
- Anterior ethmoidal nerve
- V-2 – rest of the nasal septum and cavity
- Sphenopalatine branch of V-2 via the sphenopalatine foramen
- CN I
how does the nasal cavity communicate with the paranasal sinuses?
- opening of nasolacrimal duct
- extends down into nasal cavity
what are the paranasal sinuses?
- hollow chambers named for bones in which they reside
- frontal sinus
- ethmoid sinus (air cells)
- maxillary sinus
- sphenoid sinus
how are the paranasal sinuses connected?
- frontal sinus - yellow
- maxillary sinus - orange
- ethmoid air cells - red and green
- semilunar hiatus - purple arrow
- maxillary hiatus (ostium) - blue circle
- they all drain into the nasal cavity
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how many drainage points are there in the paranasal sinuses?
5 sites of drainage
- drainage of the sinuses
- maxillary hiatus
- semilunar hiatus
- sphenothemoidal recess
- drainage of the orbit
- lacrimal duct
- drainage of the ear
- pharyngeal orifice of pharyngotympanic tube
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describe innervation of the external surface of the ear
- helix
- lesser occipital n. (C2)
- external auditory meatus
- auriculotemporal branch of the mandibular n. (V3)
- tragus
- auriculotemporal branch of the mandibular n. (V3) and great auricular n. (C2, C3)
- lobule
- great auricular n. (C2, C3)
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describe sensory innervation of the tympanic membrane
- CN V3
- X (outer)
- IX (inner)
which 2 palate muscles can be used to help clear the ears?
tensor veli palatini and levator veli palatini
describe innervation and blood supply of the middle ear - tympanic cavity
- CN IX
- CN VII
- branches of maxillary artery
what do ossicles do in the middle ear?
transform vibrations in the air (external) to waves in fluid (internal)
describe the 3 bones of the middle ear
- malleus
- on tympanic membrane
- incus
- middle bone
- stapes
- pushes on the oval window
- causes pressure gradients inside the ear to create sound
describe the internal ear
- cochlea
- semicircular canals
- innervated by CN VIII
describe the external ear muscles, what innervates them, and what arteries supply them
- auricularis anterior
- auricularis superior
- auricularis posterior
- innervated by CN VII
- supplied by p. auricular and superficial temporal aa.
what muscle closes the eyelid? and what nerve innervates it?
- orbicularis oculi m.
- CN VII
what muscles elevate the eyelid? what is the innervation?
- levator palpebrae superioris m.
- CN III
- superior tarsal m.
- sympathetics from T1 spinal cord
describe sympathetics to the superior tarsal m.
- preganglionic - T1
- postganglionic - superior cervical ganglia
- follow ICA toward targets
describe the function, drainage, innervation, and vasculature of the lacrimal apparatus
- function
- production of tears via lacrimal gland
- drainage
- medial into lacrimal sac and then nasolacrimal duct
- innervation
- greater petrosal - parasympathetic input that causes tears to be produced
- V1 is strictly sensory
- vasculature
- ophthalmic a.
describe the layers of the eyeball
- sclera/cornea
- cornea - V1 sensory; functions to refract incoming light
- choroid layer
- ciliary m. - suspensory ligaments and lens
- parasympathetic innervation (CN III)
- iris
- sphincter pupillae m. VM CN III
- ciliary m. - suspensory ligaments and lens
- retina - CN II; somatic sensory - sight
- fovea centralis
light traveling from a point very close needs ___ refraction to focus on retina.
light traveling from a distance needs ___ refraction to focus on retina.
- more
- less
describe innervation of the ciliary m. and sphincter pupillae
- CN III visceral motor parasympathetic
- arises from accessory oculomotor nucleus, synapses at ciliary ganglion, then travels to targets
describe innervation of the dilator pupillae muscles and superior tarsal muscles
sympathetic
what resutls when sympathetics to the head is interrupted?
Horner’s syndrome
- ptosis - droopy eyelid
- anhydrosis - decreased sweating
- miosis - constricted pupil
PAM has Horn’s
describe the pupillary reflex
- consensual reflex
- bilateral contraction of sphincter pupillae muscles
- CN II - input; synpase at olivary pretectal nucleus
- CN III - output; synapse at ciliary ganglion and heads to targets
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what is the primary action, secondary action, and innervation of the lateral rectus muscle?
- primary action: abduction
- secondary action: none
- innervation: CN VI
what is the primary action, secondary action, and innervation of the medial rectus muscle?
- primary action: adduction
- secondary action: none
- innervation: CN III, inferior branch
what is the primary action, secondary action, and innervation of the superior rectus muscle?
- primary action: elevation
- secondary action: adduction and medial rotation
- innervation: CN III, superior branch
what is the primary action, secondary action, and innervation of the inferior rectus muscle?
- primary action: depression
- secondary action: adduction and lateral rotation
- innervation: CN III, inferior branch
what is the primary action, secondary action, and innervation of the superior oblique muscle?
- primary action: depression and abduction
- secondary action: medial rotation
- innervation: CN IV
what is the primary action, secondary action, and innervation of the inferior oblique muscle?
- primary action: elevation and abduction
- secondary action: lateral rotation
- innervation: CN III, inferior branch
describe vasculature of the orbit
- ICA
- ophthalmic a. - enters orbit via optic foramen
- central artery of the retina
- ophthalmic a. - enters orbit via optic foramen
name the 3 superficial orbit muscles, their innervation, and blood supply
- orbicularis oculi
- corrugator supercilii
- depressor supercilii
- CN VII
- facial and ophthalmic aa.