Opthamology

Question 1

painless causes of loss of vision

Answer 1

central retinal vein or artery occlusion
retinal detachment
vitreous haemorrhage
ischaemic optic neuropathy

Question 2

what is ischaemic optic neuropathy caused by

Answer 2

arteritis eg temporal arteritis or atherosclerosis eg hypertensive, diabetic may be older patient

Question 3

what is ischaemic optic neuropathy caused by

Answer 3

occlusion of the short posterior ciliary artery, causing damage to the optic nerve

Question 4

retinitis pigmentosa

Answer 4

night blindness and tunnel vision

Question 5

horners syndrome features

Answer 5

ptosis
anhydrosis
miosis (small pupil)
enopthalmos

Question 6

how does the pupil differ in a third nerve palsy from horners syndrome

Answer 6

in horners syndrome the pupil is constricted miosis but in CNIII palsy there is pupil dilatation as CNIII cannot cause constriction so have dilated pupil and mydriasis

Question 7

what conditions can make glaucoma more likely to come on

Answer 7

WHEN THE PUPIL IS DILATED

this could be while watching television or in dim light when the light from the screen flares

Question 8

what are the risk factors for macular degeneration

Answer 8

age, smoking, family history, Caucasians, high sunlight, female

Question 9

what is the normal range of intraocular pressure

Answer 9

10-21mmHg

Question 10

Blepharitis is more common in those with which condition

Answer 10

rosacea

Question 11

what is more common anterior or posterior blepharitis

Answer 11

posterior due to meiobionan gland dysfunction

Question 12

treatement of blepharitis

Answer 12

softening of lid margin using hot compresses 2 times a day

mechanical removal of the debris from the lid margins

Question 13

what symptoms does blepharitis cause

Answer 13

dry eyes, red eyes, red eyelid margin, symptoms usually bilateral, grittiness and discomfort

Question 14

why are the eyes dry in blepharitis

Answer 14

meibomian glands secrete oil on to the surface of the eye to prevent rapid evaporation of the tear film, any problem affecting meibomian glands can hence dry the eyes leading to irritation

Question 15

why does hutchinsons sign a strong risk factor for ocular involvement

Answer 15

it indicates nasociliary involvement

Question 16

what do follicles suggest

Answer 16

viral

Question 17

what do papillae suggest

Answer 17

bacterial

Question 18

what is episcleritis associated with

Answer 18

gout

Question 19

infective ulcers tned to be found where in the cornea

Answer 19

central

Question 20

autoimmune ulcers tend to be found where in the cornea

Answer 20

in the periphery

Question 21

what are the most common organisms in acute bacterial conjuncitivits

Answer 21

staph aureus, strep pneumonia, h, influenzae

Question 22

what is the dura mater

Answer 22

tough outer protective layer

Question 23

what is the sensory supply to the dura mater

Answer 23

CN V

Question 24

what is enclosed by the dura mater

Answer 24

the dural venous sinuses

Question 25

what is in the arachnoid mater

Answer 25

arachnoid granulations

Question 26

what is the subarachnoid space

Answer 26

circulating CSF and blood vessels

Question 27

pia mater function

Answer 27

adheres to brain (and vessels and nerves entering or leaving)

Question 28

where is the subarachnoid space

Answer 28

between the arachnoid and pia mater

Question 29

what is the nerve supply to the dura mater

Answer 29

CN V

Question 30

where does the subarachnoid space close/end

Answer 30

S2

Question 31

where is the third ventricle located

Answer 31

in the midline within the diencephalon

Question 32

where is the 4th ventricle located

Answer 32

between the cerebellum and the pons

Question 33

what happens when the trochlear nerve is damaged

Answer 33

inferior oblique is unopposed eye cannot move inferomedially | diplopia when looking down

Question 34

how is abducent nerve susceptible to damage

Answer 34

from stretching

Question 35

where does the ophthalmic artery travel through

Answer 35

the optic canal

Question 36

what type of fibres are contained in the long ciliary nerve

Answer 36

sympathetic and somatic sensory

Question 37

what does the long ciliary nerve form part of

Answer 37

the afferent limb of the blink (corneal) reflex

Question 38

what do the ciliary nerves supply

Answer 38

autonomic axons to control the diameter of the iris and pupil and the refractive shape of the lens

Question 39

what do the long ciliary nerves form part of

Answer 39

the first part of the afferent limb of the blink(corneal) reflex)

Question 40

what is contained in the short ciliary nerve

Answer 40

sympathetic, parasympathetic and somatic sensory

Question 41

what kind of diplopia would damage to the suspensory ligament cause

Answer 41

vertical diplopia

Question 42

what does a fracture in the zygoma/maxilla potentially cause

Answer 42

damage to the infraorbital branch of V2 resulting in a potentially large area of altered sensation of the lower eyelid, skin over maxilla, ala of external nose and upper lip

Question 43

what is the infraorbital nerve a branch of

Answer 43

V2

Question 44

what is the angle of the mandible supplied by

Answer 44

C2,3 spinal nerves

Question 45

what is the sensory supply to the ear lobe

Answer 45

C2,3

Question 46

what is the sensory supply to the tragus

Answer 46

V3

Question 47

what supplies most of the tympanic membrane externally

Answer 47

CN V3

Question 48

what supplies the inferior part of the tympanic membrane

Answer 48

CNX

Question 49

what is the sensory supply to the Eustachian tube

Answer 49

CN IX

Question 50

what drains into the superior meatus

Answer 50

posterior ethmoidal cells

Question 51

what is the oculocardiac reflex and what nerves are involved

Answer 51

reflex bradycardia in response to tension on the extraocular muscles or pressure on the eye CNS connections between CNV1 or CNX

Question 52

what nerves are involved in coordinating the vestibulocular reflex

Answer 52

CNIII, IV, VI and VIII, 3,4,6,8

Question 53

what type of muscels is in the levator palpebrae superiooris

Answer 53

skeletal and smooth muscle

Question 54

how do sympathetic fibres reach the levator palpebrae superioris

Answer 54

superior cervical sympathetic ganglion, internal carotid nerve, internal carotid plexus, axons carried on the ophthalmic artery and on its branches to the orbital structures

Question 55

what causes the pupil to dialte

Answer 55

sympathetics, in dim light and fight or flight or non physiologically with mydriatic pupil

Question 56

where is the insertion of the dilator pupillae fibres

Answer 56

around the internal circumference of the iris

Question 57

where is the origin of the radially arranged dilator pupillae fibres

Answer 57

all around the external circumference of the iris

Question 58

what is a pinpoint pupil

Answer 58

a fixed pupil with no response to light

Question 59

what do parasympathetics do to the pupil

Answer 59

cause pupil constriction

Question 60

what is a non physiologically constricted pupil

Answer 60

miotic pupil

Question 61

what is a miotic pupil a component of

Answer 61

horners syndrome

Question 62

what is a fixed dilated (blown( pupil a sign of

Answer 62

a serios pathological sign eg of CNIII pathology | as it is inhibiting the pupillary constricting action of parasympathetic axons in the ciliary nerve

Question 63

where are the sphincter pupillae fibres

Answer 63

an encircling arrangement of the sphincter pupillae fibres all around the internal circumference of the iris

Question 64

where is the pretectal nucleus

Answer 64

in the midbrain

Question 65

where are the cell bodies of the parasympathetic axons located

Answer 65

in the edinger westphal nucleus

Question 66

explain the pupillary light reflex

Answer 66

the first neurones pass via the retinal ganglion cells to cross in the optic chiasm to the pretectal nucleus in the midbrain then synapse with edinger westphal nucleus where the cell bodies of the parasympathetic axons are located and then pass from EW nucleus VIA CNIII then its INFERIOR DIVISION to synapse in the ciliary ganglion, then course in the short ciliary nerve to the sphincter pupillae muscles

Question 67

explain the shape of the lens in far away vision

Answer 67

the ciliary muscle is RELAXED in far vision ligament TIGHTENS lens FLATTENS to focus on distant objects

Question 68

why does the lens become spherical

Answer 68

due to contraction of the ciliary muscles (CN III)

Question 69

what can lysozyme do

Answer 69

an enzyme that can hydrolyse bacterial cell walls

Question 70

what is the afferent limb for the formation of reflex tears

Answer 70

CN VI

Question 71

what type of cartilage is in the ear

Answer 71

elastic cartilage

Question 72

what 3 parts does the accommodation reflex test

Answer 72

bilateral pupillary constriction in response to CNS III bilateral convergence-medial rotation of both eyes bilateral relaxation of the lens-lens become spherical due to contraction of the ciliary muscles

Question 73

what way do you pull the ear canal in adults

Answer 73

posteriosuperiorly

Question 74

what is the angle in glaucoma

Answer 74

iridiocorneal angle

Question 75

what do the tarsal glands secrete

Answer 75

lipid

Question 76

which bone are the optic canal and the superior orbital fissure located in

Answer 76

the sphenoid bone

Question 77

where is CN II formed

Answer 77

at the optic disc

Question 78

what is at greatest density at the macula

Answer 78

cones

Question 79

what is the fovea

Answer 79

centre of the macula, depression 1.5mm diameter, area of most acute vision

Question 80

what causes the damage in giant cell arteritis to vision

Answer 80

anterior ischaemic optic neuropathy

Question 81

what are the symptoms of dacrocystitis

Answer 81

inflammation of the lacrimal sac | swelling and erythema at the inner canthus of the eye

Question 82

what is the canthus of the eye

Answer 82

either corner of the eye where the upper and lower eyelids meet

Question 83

what is dacrocysitits

Answer 83

inflammation of the lacrimal sac

Question 84

how is dacrocystitis treated

Answer 84

systemic antibiotics, IV antibiotics are indicated if there is associated periorbital cellultis

Question 85

at what age is a childs visual acuity the same as that of an adult

Answer 85

2 years

Question 86

what is a feature of keratitis

Answer 86

corneal ulcers