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82 Cards in this Set
- Front
- Back
Under unusual conditions, this layer of the eyelid may accumulate fluid (black eye).
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What is the subcutaneous tissue layer
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These structures may become infected and form a sty.
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What are the ciliary glands?
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What pathology could cause complete ptosis?
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destruction of the oculomotor nerve or one of its branches to the levator palpebrae superioris m. --> paralysis of this muscle
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What muscle (part )is responsible for gentle closing of the eyelid?
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palpebral portion of the orbiculari oculi m
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What muscle (part) is responsible for increasing lid contact to the surface of the eyeball and dilation of the lacrimal sac?
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lacrimal portion of orbicularis oculi m
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Paralysis of this muscle is responsible for the slight ptosis seen in horner's syndrome.
Why? |
1. tarsal muscle
2. This muscle is innervated by post-gang symp fibers |
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What is the significance of differentiating b/w partial and complete ptosis?
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partial = horner's syndrome (tarsal muscle)
complete = destroyed CN III which innervates the LPS m. |
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What is the location of the lacrimal gland?
Where do its ducts drain? |
1. lacrimal fossa of the orbit
2. drain into apex of superior fornix |
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What is the PSNS and SNS innervation to the lacrimal gland?
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1. PSNS: SSN --> CN VII --> greater superficial petrosal n --> vidian n --> SPG (synapse) -->maxillary n--> zygomatic n--> lacrimal n --> gland
2. SNS: SCG --> int carotid plexus --> deep petrosal n --> vidian --> etc. |
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What is the course of tears from the lacrimal gland to the nose?
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gland --> medially across cornea --> lacrimal canaliculi --> punctum --> papilla --> lacrimal sac --> nasolacrimal duct --> inferior meatus (inf. concha).
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What portion of the optic nerve is especially vulnerable to ischemia due to orbital fracture?
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The intracanalicular portion
This can happen when forces are transmitted from temporal, maxillary, and frontal regions |
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What is the most likely cause of a traumatic optic neuropathy?
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head struck by blunt object
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What passes into/out of the orbit via the superior orbital fissure?
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CN III, IV, V, & VI
ophthalmic vein |
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What passes into/out of the orbit via the inferior orbital fissure?
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infraorbital a/v
zygomatic n |
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What may happen to the structures w/in the orbit as a result of a blow-out fracture?
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herniation of structures (periorbita, inf oblique m, inf rectus m, orbital fat pad) into maxillary sinus.
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What is the classification of a maxillary fracture that occurs transversely just above the alveolar processes?
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Le Fort Type 1
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What is the classification of a maxillary fracture that involves the medial margin of one of the orbits?
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Le Forte type II
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What is the classification of a maxillary fracture that occurs transversely across the many facial bones, including both orbits?
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Le Fore type III (craniofacial dysfunction)
"panda bear face" face separates from base of the skull |
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In a Le Forte type III fracture, what would you want to be aware of possibly dripping out the nose?
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CSF ---> going to get meningitis!
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This dural layer is continuous w/ periosteal fascia, palpebral fascia, and the periosteum of the orbital rim.
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What is the endosteal dura?
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This dural layer is continuous with the sheath of the optic nerve and bulbar fascia.
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What is the meningeal dura?
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What fascia covers the optic nerve and entire eyeball except the cornea?
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Bulbar fascia
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!!!!! All of the extraocular muscles are innervated by the ____ except the _____ & _____. What are they exceptions innervated by?
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All are CN III
except: Sup oblique: IV Lateral Rectus: VI SO4 LR6 R3! |
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Paralysis of what muscle results in complete ptosis?
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LPS
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Paralysis of what muscle results in inability to abduct and ELEVATE the affected eye?
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SR
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Paralysis of what muscle results in inability to adduct the affected eye?
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MR
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Paralysis of what muscle results in aBduct and DEPRESS the affected eye?
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IR
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Paralysis of what muscle results in adduct and elevate the affected eye?
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IO
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Paralysis of what muscle results in inability to adduct and depress the affected eye?
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SO
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Paralysis of what muscle results in inability to abduct the affected eye?
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LR
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Increased ICP may compress what nerve and result in paralysis of what muscle?
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nerve: abducens (VI)
muscle: LR |
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What is the main sensory nerve to the eyball?
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nasociliary nerve (GSA)
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What nerves accompany the cavernous portion of the ICA?
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CN III, IV, V1, V2, & VI
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What are the afferent and efferent components to the corneal reflex?
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A: nasociliary nerve (VI)
E: zygomatic branch of VII |
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What are the components of the direct and consensual corneal reflex?
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Stim: lightly touch cornea
Rec: naked nerve endings on cornea Afferent: nasociliary nerve (long ciliary nn) Sensory nucleus: Descending nucleus of V Motor nucleus: facial nucleus Eff: facial n Effector: orbicularis oculi m Response: blinking |
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The ciliary canglion is located b/w what 2 structures?
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optic n
LR muscle |
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What is the general pathway of the PSNS innervation of the intrinsic muscles of the eye?
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Edinger-westphal nucleus --> ciliary ganglion --> sphincter pupillae & ciliary m
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Accommodation is a ______-mediated response.
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cortically (NOT a reflex)
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Thickening of the lens is controlled by what division of the nervous system?
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PSNS
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paralysis of what nerve results in external strabismus, complete ptosis, & dilated/unreactive pupils?
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oculomotor (III)
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Paralysis of what nerve results in inablity to adduct and depress the affected eye? The pt tends to tilt his head away from the affected eye.
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trochlear
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Paralysis of what nerve results in inability to abduct the affected eye? Diplopia occurs due to the internal strabismus.
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Abducens
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The opthalmic a courses with what nerve within the orbit?
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nasocilliary n
(later the infratrochlear n) |
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What is the chief artery of the orbit and is usually the first branch of the ICA?
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ophthalmic artery
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The opthalmic artery gives rise to the ______ & _____, both of which supply the optic nerve.
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posterior ciliary a
central retinal a |
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What is the main arterial supply to the retina?
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central retinal artery
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What 2 arteries form the arterial circle of Zinn-Haller?
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posterior ciliary a
central retinal a |
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The opthalmic a courses with what nerve within the orbit?
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nasocilliary n
(later the infratrochlear n) |
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What is the chief artery of the orbit and is usually the first branch of the ICA?
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ophthalmic artery
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The opthalmic artery gives rise to the ______ & _____, both of which supply the optic nerve.
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posterior ciliary a
central retinal a |
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What is the main arterial supply to the retina?
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central retinal artery
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What 2 arteries form the arterial circle of Zinn-Haller?
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posterior ciliary a
central retinal a |
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The central artery supplies the four quadrants of the retina through what "end" arteries?
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upper and lower temporal branches
upper and lower nasal branches |
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This is the term for the presence of blood in the anterior chamber of the eyeball (usually) due to trauma.
What artery must rupture? |
1. hyphema
2. arterial circle of iris |
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Subconjunctival hemorrhage is due to rupture of what?
Where is the bleeding restricted to? |
1. deep pericorneal plexus
2. restricted to subconjunctival tissue or bulbar fascia |
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What blood vessels are involved in conjunctivitis?
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superficial pericorneal plexus
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What nerve courses through the anterior and posterior mallear folds?
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Chorda tympani n.
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What nerve innervates the tensor tympani m?
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mandibular nerve (V)
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What two muscles protect the inner ear from excessive sound vibrations?
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1. tensor tympani m --> tightens tympanic membrane (attenuates vibrations)
2. stapedius m --> pulls out of fenestra vestibuli |
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The inner ear is supplied by what artery?
Arteriosclerosis of this artery may result in what? |
1. labyrinthine a. (from AICA)
2. vertigo, nausea, & other inner ear abnormalities |
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The bony core of the cochlea is referred to as the _____, through which the _____ passes.
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1. modiolus
2. cochlear nerve |
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The cochlear duct is attached to what structure?
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the spiral lamina
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All veins of the orbit drain into what?
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the cavernous sinus
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What CN's are tested with the corneal reflex?
What fibers/specific nerves constitute the afferent part of the reflex? |
1. V1/V2 tested
2. GSA pain/tactile fibers --> long ciliary nerves |
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What is the specific site for resorption of aqueous humor?
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sinus venosus sclera (on inner surface of irido-corneal angle)
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What is sympathetic ophthalmia?
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Condition where the damaged choroid layer of a traumatized eye may release factors that trigger an autoimmune rejection of the normal eye
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What is the site of production of aqueous humor?
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ciliary processes
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What is the afferent and efferent of the direct light reflex?
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A: optic nerve
E: oculomotor (PSNS) |
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What is the important structure in the brain responsible for the consenual light reflex?
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The posterior commisure
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What is the pathway for the direct/consensual light reflex?
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Light in retina
optic n optic tract brachium of superior colliculus superior colliculus pretectum (posterior commisure for consenual) E-W nucleus oculomoter n ciliary ganglion pupillary constrictor muscles (constriction) |
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What is the pathway for the pupillary dilation response?
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decreased light
retina optic n superior colliculus (sophisticated response involving cortical areas) pretetum reticular formation lateral reticulospinal tract pregang symp neurons (ILCC at T1) superior cervical ganglion pupillary dilator muscles (dilation) |
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What makes up the components of the triad of accommodation?
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convergence of vision (gaze)
pupillary constricion thickening of lens |
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What is the pathway for accommodation?
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(This is cortically mediated)
frontal eye field (8) corticorectal fibers superior colliculus E-W nucleus --- oculomotor nucleus ciliary ganglion \/ convergance of gaze ---- pupillary constriction/lens thickening |
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What is the critical link of the direct light reflex?
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pretectum
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What is the critical link of pupillary dilation?
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ILCC at T1
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What is the critical link of accommodation?
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cortically-mediated response
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What is the critical link of the consensual light reflex?
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posterior commisure
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You discover a pt.'s pupil will constrict upon accomodation but is unreactive to light.
What is the pathology? What structure is damaged? What is the name of this phenomenon? |
1. neurosyphilis
2. probably pretectum 3. argyll-robertson pupil |
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What is holmes-adie pupil?
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benign condition
lesion of ciliary ganglion tonic pupil --> slow to constrict on convergence |
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What are 3 mechanisms of protection from trauma in the inner ear?
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1. sudden loud sounds: footplate of stapes rocks side-to-side
2. continous loud sounds: contraction of stapedius & tensor tympani m 3. cochlear path is CNS can filter, focus, and attenuate sound. |
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Match type of sound conduction with structures responsible:
1. air transmission 2. bone conduction 3. fluid conduction |
1. EAM
2. ossicles of middle ear 3. inner ear |
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What is located in the inferio-posterior portion of the tympanic membrane?
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fenestra cochleae
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