Ophthalmology

Question 1

Where is aqueous hummour found?

Answer 1

Only in ant segment

Question 2

What are the roles of the ciliary body?

Answer 2

Controls iris
Controls shape of lense
Secretes aqueous humour

Question 3

What 4 classes of drugs are used in glaucoma treatment? and how do they work?

Answer 3

Prostaglandins (increase outflow)
Beta-blockers (decreasee production)
Carbonic anhydrase inhibitors (decrease production)
Sympathomimetics (increase outflow)

Question 4

Example of carbonic anhydrase inhibitor

Answer 4

Acetozolamide

Question 5

Which drugs CONSTRICT the pupil? Give an example

Answer 5

Parasympathomimetics (e.g. Pilocarpine)

Question 6

Which drugs DILATE the pupil? Give an example

Answer 6

Mydriatics (e.g. tropicamide, cyclopentalate)

Sympathomimetics (e.g. adrenaline)

Question 7

Which drug can cause aculopathy?

Answer 7

Chloroquine (used for rheumatoid + malaria)

Question 8

Most common causative organism in endopthalmitis

Answer 8

S. epidermis (commensal post cataract surgery)

Question 9

Causes of acute red eye

Answer 9

Endopthalmitis 
Acute angle closure glaucoma 
Scleritis
Episcleritis 
Orbital cellulitis

Question 10

Management of acute angle closure glaucoma

Answer 10

IV Diamox (Acetozolamide)
Topical anti-HTN (mannitol)
Topical steroids

Pilocarpine drop once IOP <50mmHg
YAG laser peripheral iridotomy

Question 11

How to differentiate between scleritis + episcleritis?

Answer 11

Phenylephinephrine

• vessels stay red = SCLERITIS
• completely blanches - EPISCLERITIS

Question 12

Cause of scleritis

Answer 12

CTD (always investigate further)

Question 13

Causative organisms in orbital cellulitis

Answer 13

H. influenzae, S. aureus, S. pneumonaie

direct extension from sinuses

Question 14

Management of orbital cellulitis

Answer 14

Broad spectrum abx (ceft, fluclox, met)

Question 15

Investigation for herpes simplex keratitis

Answer 15

Fluroscein (linear branching dendritic ulcer)

Question 16

Causes of bacterial conjunctivitis

Answer 16

Pneumococcus
S. aureus
H. influenzae (kids)

Question 17

Management of bacterial conjunctivitis

Answer 17

Mid - mod = erythromycin
mod-sev = ofloxacin

Gonorrhoeal = ceftriaxone + doxycycline 
Chlamydial = ophthalmic azithromycin + doxycycline

Question 18

Presentation in itreous haemorrhage

Answer 18

Painless unilateral loss of vision
Acute
Floaters/shadows/dark spots on vision

Question 19

Cause of acute visual loss

Answer 19

Vitreous haemorrhage
Retinal detachment
Central retinal artery occlusion
Central retinal vein occlusion

Question 20

4 F’s of retinal detachment

Answer 20

Floaters 
Flashes 
Field loss 
Fall in acuity 
(Painless)

Question 21

Presentation of central retinal artery occlusion

Answer 21

Painless unliateral loss of vision
RAPD
Pale, oedematous macula with cherry red spot

Question 22

Management of central retinal artery occlusion

Answer 22

Aim to dislodge clot

• ocular massage
• paper bag breathing
• IV acetalzoloamide

Question 23

Management of central retinal vein occlusion

Answer 23

No ischaemia = observe for 3m
Ischaemia = observe 4-6 wks
Neovascularisation = pan retinal photocoagulation

Question 24

Cause of gradual visual loss

Answer 24

C - Cataracts 
A - ARMD (dry)
R - Refractive error 
D - Diabetic retinopathy 
I - Inherited (retinitis pigemntosum)
G - Gaucoma 
A - Access to eye clinic
N - Non-urgent

Question 25

Presentation of dry ARMD

Answer 25

Gradual central visual loss

Drusen (calcium deposits - signifies corneal degeneration)

Question 26

Presentation of wet ARMD

Answer 26

SUDDEN central visual loss

Question 27

Management of wet ARMD

Answer 27

Anti-VEGF (e.g. ranibizumab) - prevents new vessel growth

Question 28

What does RAPD mean?

Answer 28

Problem with potic nerve communicating to brain

Question 29

Cause of fixed miotic pupil - what is this assoc with?

Answer 29

Argyll-Robertson pupil - assoc. with neurosyphillis

Question 30

What is Siedels test?

Answer 30

In trauma - fluroscein will be diluted as it leaks back to front of eye

Question 31

Management/follow-up of diabetic retinopathy

Answer 31

No retinopathy = screen 12m
Mild non-proliferative = rescreeen 12m
Mod non-proliferative = re-screen 6m
Sev non-proliferative = refer to ophthalm
Proliferative = URGENT refferral + retinal laser photocoagulation

Question 32

Classification of non-proliferative diabetic retinopathy

Answer 32

Mild = only microneurysms  >1 dot haemmorhage 
Mod = 4+ haemorrhages - but not in all 4 quadrants
Sev = "busy fundus" - large amount in all 4 quadrants