The orbital cavity: eye and lacrimal apparatus

Question 1

The medial orbital wall consists of four bones

Answer 1

the frontal process of the maxillary bone: the lacrimal bone, the orbital plate of the ethmoid bone, and the lesser wing of the sphenoid bone.

SO attaches to orbit

Question 2

difference between the axis of the eyeball (parallel) and axis of the orbit ( divergent)

Answer 2

axis of the eyeballs stragtiht through the eye straight whereas axis of the orbit is more triangular at base of pyramid from the base of pyramid

Question 3

roof or orbit formed by

Answer 3

frontal bone

Question 4

inferior wall of orbit formed by

Answer 4

maxilla and zygomatic

Question 5

medial wall of orbit

Answer 5

SELMn sphenoid ethmoid and lacrimal and maxilla

Question 6

lateral wall

Answer 6

zygomatic bone and sphenoid greater wing

Question 7

apex id the opening to

Answer 7

optic canal

Question 8

what muscles close the eyelids

inneravtion

Answer 8

orbicularis oculi

facial N. -7 hook close

Question 9

what muscle lifts the upper eyelid to open eyes

Answer 9

levator palpeerde superioris

oculomotor nerve - hold eye open

Question 10

droopy eyelid

Answer 10

interrupted sympathetic supply to mullers muscle

or ocuclomot nerve due to levator palpeerde superioris

Question 11

what glands lubricate eyelash lids

Answer 11

tarsal glands - long sebaceous glands

Question 12

lacrimal gland is made up of two bits the larger orbital gland and smaller palpebral gland. 12 ducts drain into the superior conjunctival fornix what nerve supply to this gland

Answer 12

7th cranial nerve initially and jumps onto the maxillary nerve and zygomatic branch then finally lacrimal branch

Vivian nerve/greater petrosal nerve

Question 13

contraction of lateral rectus

Answer 13

moves eye laterally

Question 14

contraction of superior rectus muscle

Answer 14

moves eye up and medially

Question 15

suprieiro oblique contraction

Answer 15

eye down and out /laterlly

incyclptrosion

Question 16

inferior oblique up and out

Answer 16

abduction and elevation and excyclotorsion

Question 17

testing the eyes

SR

Answer 17

look laterally and up

Question 18

testing IR

Answer 18

look laterally and down

Question 19

testing LR

Answer 19

laterally

Question 20

testing MR

Answer 20

look medially

Question 21

IO testing

Answer 21

look medially and up

Question 22

SO testing

Answer 22

medially and down

Question 23

right eye normal left eye is very medial what is the problem

Answer 23

palsy to laterally rectus muscle as there is no muscle tone pulling the eye laterally therefore the abducnets nerve had been palsied

Question 24

left eye normal
right eye is laterally and depressed - down and out what nerve palsy
also droopy eyelid lost levator plapeioirs
pupils dilated too - parasymptathic nerve repsonse lost

Answer 24

oculomotor never nerve injury

damage to IO and IR

Question 25

right eye fine left eye up and medially probably with head tilt

Answer 25

trochelar nerve injury - superior oblique

Question 26

3 layers of the eyeball

Answer 26

fibrous vascular inner layer

Question 27

what is contained in the fibrous layer of th eye

Answer 27

sclera and cornea

Question 28

Papilledema no pain §

Answer 28

Papilledema is swelling of your optic nerve, which connects the eye and brain. This swelling is a reaction to a buildup of pressure in or around your brain that may have many causes. Often, it's a warning sign of a serious medical condition that needs attention, such as a brain tumor or hemorrhage In patients with papilledema, vision is usually not affected initially, but seconds-long graying out of vision, flickering, or blurred or double vision may occur. Patients may have symptoms of increased intracranial pressure, such as headache or nausea and vomiting. Pain is absent.

Question 29

junction where sclera meet the cornea

Answer 29

limbus

Question 30

treatment fro retinal detachment

Answer 30

scleral buckle

Question 31

sclera icterus - due to hepatic failure and jaundice

Answer 31

yellow eyes - bilirubin build up

Question 32

red blood shot eye due to to

Answer 32

vessel dilating - sign of allergic reaction or irritation

Question 33

what is conjunctiva

Answer 33

tissue that lines the inside of the eyelids and covers the sclera

Question 34

corneal abrasion - scratch on eye

Answer 34

most people recover in few days

Question 35

keratoconus sx

Answer 35

cornea forms a cone the black bit of the eye looks like it is dropping eye cannot focus as well centrally

Question 36

vascular layer of th eye is composed of

Answer 36

choroid , ciliary body and iris

Question 37

iris is like a diaphragm | ciliary body controls shape of

Answer 37

the lens

Question 38

nerve supply of ciliary muscles

Answer 38

CN3 - para supply and ganglion close to eyeball

Question 39

ciliary muscle does what

Answer 39

lgimanets pull lens out | when it contract it relaxes suspensor ligaments and the lens become more spherical

Question 40

ctatcarct surrgyer

Answer 40

phacoemulsifcation | inside of lens stopped out and replaced with a plastic one

Question 41

parasympathetic stimulation causes circular muscle to contract - constrict synpathetic stimulation causes radial muscle to contact - dilate all consoled by what

Answer 41

iris

Question 42

horners syndorme

Answer 42

ptosis - one eye ( two could be problem with mysathneai) anhidrosis and misois ( constructed pupil) constricted pupil , misois and ptosis

Question 43

drugs fro dilating pupils - mydriatic medications

Answer 43

tropicamide and atropine ( parasympathetic antagonist) gives opthalmogist a better view of retina and optic nerve contracts the radial pupil smooth muscle making it much bigger and clearer to see

Question 44

inner eyes contain the retina | rods and cones what is the difference

Answer 44

rods see black and white - used at night - sensitive to low light conditions - rods are mainly round periphery of your retina so look out the corner of your eye cones - work ind daylight conditions - colour and tightly packed in the centre of the retina to get high reolstuion in the centre of your eye colour vision evolved when we ate fruits seeing red apple against leaves 3cones blue - chromosome 7 red and green - x chrosmoem - which is why you get red green colourblindness most commonly in males - inherited from the mum

Question 45

centre of retina called

Answer 45

macula - got a yellow pigment | retina ends at ora serratus at the peripheries

Question 46

under light ophthalmoscope where do you find the macular and optic disc

Answer 46

macular is dead centre and optic disc is towards the right edge - medially aspect of the eye

Question 47

age related macular degeneration - blinds rare sx

Answer 47

forms a cloud in the centre of the pcitreu yellow drusen - loss of sensory cells and get colour vision loss and lose centra vision wet and dry dry - build uo wet - get new vessel formation - treated with lcuentivez stop progression

Question 48

retinitis pigmentosa

Answer 48

dangerous for driving

Question 49

ant chamber and post chamber either side of the

Answer 49

iris

Question 50

what fluid in ant chamber

Answer 50

aqueous humour

Question 51

what fluid in post chamber

Answer 51

vitreous chamber has hyaloid canal - can get a vessel if it drops off and forms floaters in the ey - look like colourless worms of hair

Question 52

pending retinal detachment

Answer 52

eye floaters due to vitreous humour vitrectomy procedure

Question 53

aqueous humour ha high turn over | too high build of aqueous humour causes what

Answer 53

glaucoma - blockage to canal of schlem ``` Glaucoma Causes: 1. Insufficient drainage of Canals of Schelm then veins 2. Iridocorneal angle could narrow  Treatment: 1. Drugs improving the flow at the Canals of Schelm (drugs similar to prostaglandins) 2. Decreasing aqeous humour production (beta ``` -adrenergic ``` receptor antagonists) 3. Vasoconstriction of arteries of the ciliary body (epinephrine) 4. Insertion of glaucoma drainage implants ```