Clinical Pathology

Question 1

what is cataracts?

Answer 1

blurring of the lens

Question 2

maincauses of cataracts?

Answer 2

sun damage
diabetes
genetic
hypertension
smoking
post-op and trauma
metabolic disorders

Question 3

what is glaucoma?

Answer 3

abnormal increase in pressure in the eye

- related to the amount of vitreous fluid and anteriorly aqueous humour

Question 4

where does the aqueous fluid usually drain?

Answer 4

trabecular meshwork/canal of schlemm into scleral venous sinus
blockage of this can cause increased pressure and lead to glaucoma

Question 5

what is the consequence of increased pressure in the eye?

Answer 5

mainly causes problems at the back of the eye (optic nerve etc)
structures at the front can be compressed

Question 6

what is the most common type of glaucoma?

Answer 6

primary open angled glaucoma
drainage of aqueous humour is blocked
secretion of aqueous humour is clear

Question 7

what is angle closure glaucoma?

Answer 7

where drainage through the meshwork is patent
iris is essentially opposed to anterior eye and fluid cant get passed to the meshwork
(iridocorneal angle?)

Question 8

open glaucoma?

Answer 8

slow onset
often asymptomatic and now screened for
many people don’t know they have it
pharmacological therapy aimed at slowing it down by widening canal etc

Question 9

closed glaucoma?

Answer 9

1/3 are a medical emergency

can lose sight v quickly

Question 10

how does closed glaucoma present?

Answer 10

acute red eye
visual loss
headache nausea and vomiting

Question 11

how is closed glaucoma managed?

Answer 11

zap a hole in iris with a laser

Question 12

what is cupping?

Answer 12

raised intraocular pressure which damages the optic disc and nerve
essentially the edges of the disc become rolled up and the centre becomes depressed
sign of raised intraocular pressure

Question 13

what is papilloedema?

Answer 13

swelling of the optic nerve/disc

non-specific finding related to raised intracranial pressure

Question 14

what is conjunctivitis?

Answer 14

inflammation of the conjunctiva

Question 15

how does conjunctivitis present?

Answer 15

swelling
redness
pain
heat

Question 16

causes of conjunctivitis?

Answer 16

usually viral
occasionally bacterial
sometimes allergic

Question 17

what is scleritis?

Answer 17

inflammation of sclera

Question 18

how does scleritis rpesent?

Answer 18

pain onmovement

Question 19

what underlying pathology can be associated with scleritis?

Answer 19

can have an underlying autoimmune aetiology

• SLE
• HLA B27

Question 20

what is episcleritis?

Answer 20

superficial inflammation of sclera
less severe than scleritis
self limiting

Question 21

causes of episcleritis?

Answer 21

usually no real cause

Question 22

what is ARMD and what 2 types exist?

Answer 22

ARMD = age related macular degeneration
dry = no vascular proliferation
wet = vascular proliferation (worse than dry)

Question 23

what causes ARMD?

Answer 23

unclear
age-related and underlying inflammatory process
accumulation of by-products (drusen)

Question 24

what is drusen?

Answer 24

proteins and lipids and inflammatory mediatory
by-product of inflammatory process
present in macular degeneration
shows as yellow bits in retina

Question 25

what causes wet ARMD?

Answer 25

neovascularisation in choroid new vessels are small and fragile and therefore leaky more lkely to result in visual loss

Question 26

how is wet ARMD managed?

Answer 26

monoclonal antibodies to VEGF

Question 27

what mediated wet ARMD?

Answer 27

VEGF

Question 28

how can diabetes affect the eye?

Answer 28

cataract hyperglycaemia (changes osmotic pressure in anterior chamber) blurred vision (often presenting complaint in T1DM) pupils - Argyll Robertson pupil, peripheral neuropathy

Question 29

what is Argyll Robertson pupil?

Answer 29

accommodation reflex intact | light reflex not intact

Question 30

how does diabetes cause cataracts?

Answer 30

increased sugar content in lens conversion of glucose to sorbitol altered gradients - swelling and fibre disruption scarring

Question 31

what is diabetic glaucoma known as?

Answer 31

rubeotic glaucoma

Question 32

how does diabetes cause glaucoma?

Answer 32

new vessel formation obstructing angle

Question 33

how does diabetic retinopathy occur?

Answer 33

complex mechanisms leading to poor function of vessels leaky vessels and small aneurysms forming if severe - new vessel formation oedema if macula affected, visual loss is worse

Question 34

name 2 vascular diseases of the eye

Answer 34

central retinal artery occlusion (CRAO) | central retinal vein occlusion (CRVO)

Question 35

causes of CRAO?

Answer 35

``` thromboembolic disease (often originating in carotids) same pathogenesis as arterial occlusion anywhere else in the body ```

Question 36

causes of CRVO?

Answer 36

thrombosis | vasculitis

Question 37

what vasculitis is most likely to affect the eye?

Answer 37

giant cell

Question 38

what cutaneous cancers can occur in the eye?

Answer 38

BCC SCC melanoma retinal melanoma