Ear, Eye

Front 1

the external ear canal is through what bone?

Back 1

the temporal bone

Front 2

the ear canal is 2–3cm long, what are the different parts of it?

Back 2

lateral 1/3rd: cartilaginous with auricular skin

medial 2.3rds bony with skin cont. with tympanic membrane

Front 3

What is the lining of the tympanic membrane?

Back 3

externally: lined with thick skin
internally: with mucous membrane

Front 4

the tympanic cavity or the middle ear is an air cavity within the temporal bone, what is its contents?

Back 4

auditory muscles
audiotry ossicles
tympanic plexus (from glossopharyneal n)
chorda tympani nerve (CN VII)

communicates with the pharynx via pharygotympanic tube

Front 5

what are the borders of the middle ear compartment? as a box

Back 5

sup roof: thin plate of temporal bone
lateral wall: membranous with tympanic mem
inf floor: jugular wall (separates from IJV)
medial wall: labyrinthe wall
posterior wall: mastoid wall
anterior: carotid wall

Front 6

where are the auditory ossicles located?

Back 6

Front 7

what are the articulations between the malleus, the incus and the stapes?

Back 7

incus articualrtes with the he'd of the malleus and the head of stapes

Front 8

where is the malleus imbedded into?

Back 8

the tympanic membrane

Front 9

what two structures does the 3 auditory ossicles connect to conduct vibrations?

Back 9

tympanic membrane to the ovale window

Front 10

what is the pharyngotympanic tube?

Back 10

connects the tympanic cavity to the nasopharynx

function to equalise pressure within the middle ear

upper 1/3 is bony

lower 2/3 cartilaginous

Front 11

what is the vestibulocochlear apparatus?

Back 11

recess in the temporal bone which form tiny bony labyrinths

vestibular and semi-circular ducts are involved with the position and motion of the head

Front 12

what is the difference between conductive hearing loss or sensorineural hearing loss?

Back 12

conductive: external middle ear problem-sound waves aren't be transmitted

sensorneural: damage to neural pathways and cochlear hair cells, CN VIII, brain damage

Front 13

what muscle helps reduce white noise?

Back 13

tensor timpani-innervated by mandibular nerve

Front 14

What is the conjunctiva?

Back 14

covers the eyeball

palpebral conjunctiva: on inferior eyelid refecting onto eyeball

bulbar conjuctiva: covers sclera

Front 15

where do the lines of replection of palpebral conductiva meet and what do they form?

Back 15

superior and inferior conjuctival fornices and the conjunctival sac enables free movement of eyelids

Front 16

what is the lacrimal apparatus?

Back 16

canaliculi (small canals) that carry lacrimal fluid from lake (in medial corner of eye) to sack

Front 17

what is the caruncle?

Back 17

small mound of moist modified skin in medial corner of eye

Front 18

what are the 3 layers of the eyeball?

Back 18

fibrous layer(outer)-shape resistance

vascular layer(middle)

inner layer (inner coat)

Front 19

which part is the sclera and the cornea and what is their funciton

Back 19

sclera: white, tough and 5/6ths of eye and provides attachments for muscles

cornea: transparent layer, 1/6 of eyeball, protrudes from eyeball, innervated by CN V1-blinking and tears

Front 20

what is contained within the vascular layer?

Back 20

choroid-between sclera and retina, cont with ciliary body

ciliary body-ring like thickening, connects choroid to iris, attachment for lens and controls thicknesss of lens for focus and the aq. humour which fills the ant. segment of the eye

iris- ant of lens, thin, contractile diaphragm, pupil is central aperture to transmit light

Front 21

what are the parts of the inner layer?

Back 21

optic part: neural layer and pigmented

non-visual part: cont of pigment layer, covers ciliary body and covers post. iris

Front 22

what are the parts of the retina?

Back 22

fundus: where the light is focused includes optic disc, no photo receptors

macula: yellow spot, oval shaped, specialised for acuity,macula lutea (outer) fovea centralism (middle) foveola (inner)

Front 23

The eye can be divided into anterior and posterior division, what is in and where is the anterior chamber?

Back 23

between cornea and irish and pupil

occupied by aqueous humour

Front 24

what is in and where is the posterior chamber?

Back 24

between lens and ciliary body

ciliary body produces aq. humour

Front 25

what is aqueous humour?

Back 25

clear, watery solution, provides nutrients to cornea and lens, passes through pupil to anterior chamber, drains through trabeolar meshwork into scleral venous sinus and it is removed by gimbal plexus

controls intra-occular pressure

Front 26

what anchors the lens capsule?

Back 26

zonular ligaments

Front 27

what is the function of the lens?

Back 27

fine tune focus, ciliary muscle changes the shape of the lens

less convex for for far vision, more convex for near vision

Front 28

what happens to the ciliary muscle to look at distant ojects?

Back 28

if no stimulation, ciliary muscle is relaxed zonular fibres are under tension causing the lens to be stretched thin to refract light for distant vision

Front 29

what kind of stimulation stimulates the ciliary body to contract for near vision to allow the zonular fibres to relax so the lens can be more spherical?

Back 29

parasympathetic stimualtion

Front 30

what is vitreous humour?

Back 30

watery fluid, enclosed in virtues body and transmits light and holds retina in place and supports the lens

Front 31

what occurs in cataracts?

Back 31

loss of transparency of the lens and areas of opaqueness, treat by surgical removal

Front 32

what muscles contract and dilate the pupil?

Back 32

sphincter pupila: pupil contrictor (circular)

dilator pupila (long fibres)

Front 33

what are the bones that make up the floor of the orbit?

Back 33

palatine bone,zygomatic and maxilla

Front 34

what bones make up the lateral wall of the eye?

Back 34

greater wing of sphenoid and zygomatic

Front 35

what bones make up the roof of the eye?

Back 35

frontal bone and lesser wing of sphenoid

Front 36

what bones make up the medial wall of the orbit?

Back 36

ethmoid, lacrimal, palatine and maxilla

Front 37

where do the rectus muscles attatch?

Back 37

common tendinous ting to the ant 1/2 of the eyeball

Front 38

what is the innervation of the the rectus muscles?

Back 38

oculomotor nerve (CNIII)

except lateral rectus=abducent CN VI

Front 39

what is the action of the superior and inferior rectus?

Back 39

sup: elevation, adduction, medial rotation

inferior: depression, adduction and lateral rotation

Front 40

what is the attatchment and the innervation of the superior oblique?

Back 40

sphenoid bone to post 1/2 of the eye

trochlear nerve CN IV

Front 41

what is the attatchment and the innervation of the inferior oblique?

Back 41

med floor of orbit post to rim to posterior 1/2 of the eye

occulomotor nerve CN III

Front 42

what is the blood supply to the eye?

Back 42

internal carotid-opthalmic artery-opthalmic artery branches to supply the eye

Front 43

where is the opthalmic artery in relation to the optic nerve?

Back 43

both pass through the optic canal and the nereve is inferior and lateral to the nerve than moves superior and medial

Front 44

what is the venous drainage of the eye?

Back 44

superior opthalmic vein (through sup. orbital fissure to cavernous sinus) and inferior opthalmic vein (through sup. orbital fissure into cavernous sinus)

Front 45

what fibres are contained within the optic tract?

Back 45

medial fibres from the opposite eye and lateral fibres of the same eye, surrounded by cranial meninges and leaves via the optic canal

Front 46

what part of the eye would be damage to create monocular blindness?

Back 46

the optic nerve (directly behind the eye ball)

Front 47

what part of the eye would be damaged to produce bitemporal hemianopias? (only see the two inner halfs of each eye)

Back 47

the optic chaism (contains medial fibres of each eye)

Front 48

what part of the eye would be damaged to produce left homocygous hemianopia (left side is black on both eyes)

Back 48

between chiasm and cortex on the RIGHT SIDE