WEEK 8 - EYE

Question 1

What does the bony orbit of the eye house

Answer 1

eyeball, extra-oricular muscles, lacrimal gland, periorbital fat, nerves and blood vessels

Question 2

what is the bony orbit lined with

Answer 2

orbital periosteum and filled with orbital fascia - coarsely loculated fat

Question 3

list the seven bones that contribute to the bony orbit

Answer 3

• frontal
• zygomatic
• maxilla
• sphenoid
• ethmoid
• lacrimal
• palatine

Question 4

bone of the roof of the orbit

Answer 4

frontal and lesser wing of sphenoid

Question 4

bones of the floor of the orbit

Answer 4

maxilla, zygomatic and palatine

Question 5

bone of the medial wall of the orbit

Answer 5

maxilla, lacrimal, ethmoid, sphenoid body

Question 6

bones of the lateral wall of the lateral wall of the orbit

Answer 6

zygomatic
greater wing of sphenoid

Question 7

list the seven muscles of the extrinsic eye muscles that move the eyeball within the bony orbit

Answer 7

• four recti > superior, inferior, medial and lateral
• two oblique > superior and inferior
  LEVATOR PALEBRAE SUPRIORIS (ELEVATES UPPER EYELID)

Question 8

what are the extrinsic eye muscles innervated by

Answer 8

oculomotor nerve
except for superior oblique > trochlear nerve

Question 9

function of levator palpebrae superioris

Answer 9

elevates the upper eyelid
frontal nerve is superior to LPS in orbit

Question 10

where do recti muscles insert into

Answer 10

SCLERA about 6mm behind cornea and anterior to equator of eyeball

Question 11

where do all recti muscles arise from

Answer 11

tendinious ring around optic nerve

Question 12

what does the lateral rectus have an addition of

Answer 12

additional head that originates from lateral margin of superior orbital fissure

Question 13

where does the superior oblique muscle originate from

Answer 13

body of sphenoid

Question 14

where does the inferior oblique muscle arises from

Answer 14

orbital surface of maxilla lateral to nasolacrimal groove

Question 15

where are lacrimal glands located

Answer 15

superolateral orbit
some in eyelid lateral to tarsal plate between conjuctiva and palpebral fascia

Question 16

what do lacrimal glands secrete

Answer 16

serous products under the control of the facial PNS fibers that hitchhike on the lacrimal gland

Question 17

what do tears contain

Answer 17

• serous secretion
• mucus secretion
• sebaceous secretion

Question 18

where do tears drain from

Answer 18

into the medial corner of the eye and from there via lacrimal puncta into lacrimal canaliculi and lacrimal sac and ultimately into the nasolacrimal duct

Question 19

where does the nasolacrimal duct drains into

Answer 19

inferior nasal meatus of nasal cavity

Question 20

where does the tendon of levator palpebrae superioris insert into

Answer 20

upper eyelid

Question 21

list the three layers of the eyeball

Answer 21

• fibrous layer
• vascular layer , uvea
• neural layer

Question 22

what is within the fibrous layer of the ey

Answer 22

sclera and cornea

Question 23

what is within the vascular layer of the eye

Answer 23

choroid, ciliary body and iris

Question 24

what is within the neural layer of the eye

Answer 24

retina

Question 25

which component of the eye is the main refractive appartus of the eye and functions to focus light onto retins

Answer 25

cornea

Question 26

what does the cornea continue as posteriorly

Answer 26

sclera

Question 27

list the three parts of uvea

Answer 27

- choroid - ciliary body - iris

Question 28

list the two parts of the retina

Answer 28

sensory retina non sensory retina

Question 29

how many layers does sensory retina have

Answer 29

10

Question 30

what does non sensory retina forms

Answer 30

- posterior part of the ciliary body and iris

Question 31

what is the junction with non sensory retina of ciliary body

Answer 31

ora serrata

Question 32

where is the pigmented epithelium of sensory retina

Answer 32

rods and cones

Question 33

what are the other layers of sensory retina

Answer 33

bipolar and ganglion cells involved in transmitting signal from photoreceptors to optic nerve

Question 34

what is the optic disc

Answer 34

special region of the sensory retina at the site of the entry of optic nerve

Question 35

what is macula/fovea

Answer 35

region adjacent to the optic disc where all elements of the retina except cones are reduced = region of greatest visual acuity

Question 36

what does the iris control

Answer 36

amount of light entering the eye through pupil

Question 37

what does the anterior and posterior part of iris consists of

Answer 37

- anterior > uvea - posterior > non sensory retina

Question 38

what can the iris do

Answer 38

contract and dilate

Question 39

how does contractin in iris occur via

Answer 39

circular muscle > pupillary sphincter around pupil that is controlled by parasympathetic fibrs of oculomotor region

Question 40

how does dilation in iris occur via

Answer 40

- radial muscles (pupillary dilator) controlled from sympatheric fibers

Question 41

what is the lens tethered to

Answer 41

ciliary body by zonular fibers

Question 42

what is the lens covered by

Answer 42

acellular capsule

Question 43

how many cell layers thick is the lens

Answer 43

2 cell layers

Question 44

what does the anterior layer of the lens consist of

Answer 44

cuboidal epithelial cells

Question 45

what does the posterior layer of the lens consist of

Answer 45

elongated cells

Question 46

what does the ciliary body consist of

Answer 46

- ciliary body - ciliary processes

Question 47

what is the ciliary body for

Answer 47

accomodation for far and near visionj

Question 48

what does the ciliary processes produces

Answer 48

aqueous humour

Question 49

what does the ciliary processes consists of

Answer 49

uvea anteriorly non-sensory retina posteriorly

Question 50

how does ciliary body accomodate for near vision

Answer 50

sphincter of ciliary body contracts > resulting in less tension on zonular fibres and LESS pull > lens rounds out

Question 51

how does ciliary body accomodate for far vision

Answer 51

sphincter of ciliary body relaxes > more tension on zonular fibres, MORE pull on lenses > flattens the lens

Question 52

list the segments of the chambers

Answer 52

anterior and posterior segments

Question 53

list the two humours

Answer 53

- aqueous humour - vitreous humour

Question 54

where is aqueous humour produced in

Answer 54

folds of ciliary body and transported into posterior chamber, passes through pupil into anterior chamber

Question 55

where does the aqueous chamber drain via

Answer 55

drains from eye via scleral venous sinus (canal of schlemm) and from there into venous system while the remaining 20% drains into the uveoscleral ang;e

Question 56

what does the vitreous humour fill up

Answer 56

vitreous chamber behind the lens

Question 57

list the contents in the refractive media

Answer 57

cornea aqueous humour lens vitreous body

Question 58

what does optic nerve innervate

Answer 58

vision

Question 59

what does oculomotor innervate

Answer 59

most extrinsic eye muscles except for superior oblique and lateral rectus

Question 60

what does trochlear nerve innervate

Answer 60

superior obliquew

Question 61

what does abducens nerve innervate

Answer 61

lateral rectus muscle

Question 62

what does the maxillary nerve pass into orbit as

Answer 62

infraorbital nerve

Question 63

where does oculomotor, trochlear, ophthalmic and abducens nerve pass through

Answer 63

cavernous sinus along with internal carotid artery which carry sympathetic plexus

Question 64

what does the optic nerve contain predominantly

Answer 64

sensory nerves afferents to the brain

Question 65

where does the optic nerve pass across

Answer 65

inner surface of the retina and through the optic disc to become the optic nerve

Question 66

what else does the optic nerve contain

Answer 66

efferent (motor) Fibres that play a role in light adaptation and reflex

Question 67

ciliary parasympathetic ganglions are innervated by

Answer 67

oculomotor nerve which is connected to the inferior division via small connecting branch

Question 68

what is ciliary ganglion connected to

Answer 68

nasociliary ganglions via sensory root

Question 69

where is ciliary ganglion located

Answer 69

lateral region of orbit ~1cm anterior to the tendinuous ring surrounding optic nerve

Question 70

what does trochlear nerve supply

Answer 70

superior oblique muscles superior border of superior oblique muscle

Question 71

what does abducen nerve supply

Answer 71

lateral rectus muscle

Question 72

where does ophthalmic nerve pass through

Answer 72

superior orbital fissure

Question 73

list the terminal branches of ophthalmic nerve

Answer 73

LATERAL TO MEDIAL lacrimal frontal nasocilliarey

Question 74

what does lacrimal nerve supply

Answer 74

sensory to lacrimal gland and skin

Question 75

where does frontal nerve pass

Answer 75

over LPS and divides into two cutanoues brnaches

Question 76

list the two cutaneous branches of LPS

Answer 76

supratrochlear supraorbital

Question 77

what does nasociliary nerve gives rise to

Answer 77

anterior and posterior ethmoidal nerves

Question 78

where does parasympathetic and sympathetic fibres pass through

Answer 78

sclera to reach iris and ciliary body

Question 79

purpose of parasympathetic innervation

Answer 79

contract sphincters of pupils and ciliary body