Ocular Pathology

Question 1

what is the normal IOP?

when do problems occur?

Answer 1

12-20 is normal
damage at 25-35
can go as high as 60-70

Question 2

describe retinal detachment process +

is it painful?

Answer 2

a tear in the retina leads to vitreous pouring out through it, pulling on the retina until it collapses. The macula may be left unaffected (macula sparing).

mechanical energy = flashes

pigmented free bodies = floaters

may have RAPD

often painless

Question 3

what arteries are occluded in ION ?
common condition this happens in?
Outcomes?

Answer 3

Posterior ciliary arteries to head of optic disc = occluded

common in GCA inflammation

irreversible

Question 4

describe Wet ARMD

what vision problem is commom?

Answer 4

new vessels under the retina leak - fluid and blood builds up

new vessels are often VEGF mediated!

Metamorphosia is common (distorted lines)
Also scotoma (blind spot)

Question 5

describe classic fundoscpy of central retinal artery occlusion

changes with branch?

Answer 5

pale optic disc
macula is darker “cherry red spot

branch- an area of ischaemic is pale. may still have dark macula

Question 6

thromboembolisms cause central arterial occlusions - where from

Answer 6

carotids

Question 7

describe a fundoscopy of retinal vein occlusion

Answer 7

dot + blot + flame haemorrhages. dark.

optic disc normal

widespread if central but localised if branch

Question 8

what is amueurosis fugax? classic history ?

Answer 8

transient painless vision loss for 2-3 mins. a TIA.

“sudden darkness”

likely to have AF + cardiac risk factors eg hypertension

Question 9

describe closed angle glaucoma symptoms + who normally gets it.

treatment?

Answer 9

classic in elderly long sighted

treatment - LASER a hole in RETINA (cool)

painful red eye
cloudy cornea / dilated
headache
Nausea + VOMITTING

Question 10

describe dry ARMD + its treatment

Answer 10

drusen (inflamm by-products) collects underneath the retinal PE, stopping nutrition of retina.

retina becomes atrophic, with damage to the macula in centre

there is no treatment

Question 11

symptoms of open angle glaucoma

tx?

Answer 11

may often be asymptomatic

may have peripheral visual field defect

Tx is IOP lowering medication (opens gap or turns off aqueous tap)

Question 12

where does the light focus in myopia + hypermetropia

and what type of classes does each need?

Answer 12

myopia = light focuses too anteriorly = concave glasses

hypermetropia = light focuses too posteriorly = convex glasses

Question 13

what is astigmatism + presbyopia

Answer 13

astig - irregularly curved cornea

pres - loss of ability to accommodate when getting older. lens problem not a problem with focusing

Question 14

describe the 4 separate cause types of Papilloedema

Answer 14

1. SOL (worst so until proven otherwise)
2. Malignant hypertension - always check bp - give emergency medication IV to lower it
3. CSF issues - obstruction/ overproduction/ poor absorption
4. Idiopatic intracranial hypertension - poorly understood - probably a CSF issue. normally obese

Question 15

how can death occur in high ICP?

Answer 15

brain herniates through foramen magnum
compresses brainstem so stop breathing

or global brain ischaemia