Opthalmology

Question 1

Changes seen in ARMD vs diabetic vs hypertensive retinopathy?

Answer 1

ARMD: drusen, choroidal neorevascularisation (wet AMD - 10% of cases), geographic atrophy (dry AMD - 90% of cases)

Diabetes: microaneurysm, dot & blot and flame haemorrhages

HTN: copper wiring, AV nipping, dot, blot and flame haemorrhages, cotton wool spots, papilloedema

Question 2

tx of chronic open angle glaucoma

Answer 2

360 selective laser trabeculectomy if pressure >24mmHg

prostaglandin analogue (latanoprost)

beta-blocker eye drop (timolol)
carbonic anhydrase eye drop (bitanoloprost, brinzolamide)
sympathomimetic eye drop (pilocarpine, brimonidine)

Question 3

Tx of acute closed angle glaucoma

Answer 3

IV acetazolamide
Topical pilocarpine
Surgical or laser iridotomy

Question 4

difference between pterygium and pinguecula?

Answer 4

Pterygium: go beyond cornea

Pinguecula: doesn’t reach cornea

Both: are benign growths of conjunctiva that comes from the nasal side. wedge shapes and moves towards the centre as it is a continuation of the conjunctival epithelium.

Question 5

differences between:
central scotoma
arcuate scotoma
centrocaecal scotoma
ring scotoma

Answer 5

central: cannot see the centre of visual field. seen in diseases affecting the macula - eg age-related maculopathy

arcuate: cannot see one part of the visual field - seen in glaucoma

centrocaecal: cannot see from the centre and it radiates out (like a caecum). it often involves the macula and the blind spot. seen in toxic/nutritional deficiencies (eg vit B12) or leber’s optic neuropathy.

ring: cannot see the area in a ring-like pattern (but can still see the centre of visual field). seen in retinitis pigmentosa.

Question 6

when looking at differences in symptoms between orbital cellulitis OC and preseptal cellulitis PC, which symptom presents in OC but not PC?

Answer 6

proptosis
visual changes
pain on eye movement
restriction of eye movement
RAPD

(but they both contain these:) swelling or erythema of eyelid, periorbital oedema, ptosis

Question 7

warm or cold compress for
- stye/hordeolum (hair follicle)
- blepharitis
- chalazion/meibomian cyst (blocked gland)

Answer 7

warm compress

Question 8

a curtain or dark shadow moving across vision towards the centre -?diagnosis

Answer 8

transient loss of vision (TVL) aka amaurosis fugax

usually due to ischaemic or non-ischaemic cause:
- ischaemic: GCA, CVA, retinal arteriolar emboli (if affect one eye: likely anterior circulation affected such as carotid artery. if affect both eyes, consider posterior circulationn affected such as basilar artery/vertebral artery)
- non-ischaemic: dry eyes, migraine

Question 9

which topical antibiotic should be avoided for pregnant lady with conjunctivitis?

Answer 9

chloramphenicol
(there may be a risk of ‘neonatal grey baby syndrome’ with oral use in 3rd trimester but no studies for topical use)

Question 10

what is:
- hard exudate
- soft exudate

Answer 10

Hard: well defined yellow-white deposits like ring. Due to lipoprotein leaking out of blood vessel. Seen in diabetes & HTN.

Soft: like cotton-wool. Occur in infarcted retina. Due to swelling of the axons in the nerve fibre of the retina.

Question 11

red eye that improves with topical phenylephrine

Answer 11

episcleritis

Question 12

what eye pathology is linked with connective tissue disease such as ehler’s danlos and marfan syndrome?

Answer 12

lens dislocation (upwards for Marfan)
Keratoconus

Question 13

tx of allergic conjunctivitis

Answer 13

topical antihistamine (eg diphenhydramine)
systemic antihistamine
topical mast cell stabilisers: sodium chromoglycate, nedocromil

Question 14

4 features of retinal detachment

Answer 14

4F’s
floaters
flashing lights (photopsia)
field loss
fall in visual acuity

Question 15

keith-wagener-barker classification

Answer 15

for HTN-retinopathy

Grade 1 - arteriolar narrowing
Grade 2 - plus AV nipping
Grade 3 - plus microaneurysm, dot-blot haemorrhages, flame shaped haemorrhage, cotton-wool spots and hard exudate
Grade 4 - plus optic disc swelling

Question 16

tx of orbital cellulitis

Answer 16

ABX
- Penicillin or cephalosporin
- if pen allergic: cefuroxome & clarithryomycin IV OR clindamycine and ciprofloxacin IV

Question 17

Uveitis - usually linked with what diseases?

Answer 17

Anterior uveitis: usually ank spon and reactive arthritis

Posterior uveitis & usually bilateral & chronic: psoriatic arthritis and IBD

Question 18

different stages of diabetic retinopathy

Answer 18

background: blot haemorrhages, microaneurysm, hard exudate

pre-proliferative: cotton wool spots, intraretinal microvascular anomalies

proliferative: new vessels and fibrosis - can cause retinal detachment or vitreous haemorrhage

Question 19

signs/symptoms of CNIII palsy

Answer 19

ptosis
diplopia
pupils out and down
mydriasis

Question 20

Holmes Adie pupil -what is it?

Answer 20

parasympathetic denervation of the afflicted pupil
- dilated at rest initially and then become small chronically
- poor/sluggish response to bright light and NORMAL (not slow!) accommodation
- deep tendon reflexes

Question 21

Argyl Robinson pupil

Answer 21

reacts poorly to light BUT quick to accommodation
- seen in neurosyphilis
bilateral tonically small pupils that reats poorly or not at all to light but briskly to accommodation (light-near dissociation)

Question 22

Marcus Gunn pupil

Answer 22

RAPD
unilateral dysfunction of optic nerve or retina
relative weakness of the afferent limb of the pupillary light reflex compared to the other eye

Question 23

what is tobacco-alcohol amblyopia?

Answer 23

defective vision arises as the anterior visual pathway is susceptible to damage from toxins or nutritional deficiency

?cyanide toxicity or undernutrition

central loss of vision for colours, optic atrophy

Question 24

blurred vision, painful and loss of colour vision
?diagnosis

Answer 24

optic neuritis - need to rule out MS

Question 25

sudden onset periorbital pain with reduced visual acuity, conjunctival injection, mid-dilated pupil and non-reactive pupil

?diagnosis

Answer 25

acute CLOSED angle glaucoma

Question 26

sudden onset eye pain and discomfort with irregular small pupil. photophobia present. blurred vision with red eye.

?diagnosis

Answer 26

anterior uveitis

Question 27

most common organism for conjunctivitis

Answer 27

viral: adenovirus
bacterial: strep penumonia, staph aureus, haem influenza

for opthalmia neonatorum (within 4 weeks of life)- chlamydia trachomatis is most common. other causes: neisseria gonorrhoea, haemophilus, strep & staph, e.coli, pseudomonas, adenovirus, H. simplex

Question 28

red flags for conjunctivitis

Answer 28

reduced visual acuity
marked eye pain, headache, photophobia
red sticky eye in neonate
history of trauma
copious rapidly progressive discharge
herpes infection
soft contact lens use with corneal symptoms (photophobia and watering)

Question 29

cannot close eyes post-blepharoplasty operation -? complication

Answer 29

lagophthalmos (inability to close eye fully due to too much excess skin/fat removed in surgery)

Question 30

how does anterior VS posterior uveitis present?

Answer 30

Anterior: painful red eye, photophobia, blurred vision. no mucopurulent discharge -just watery one. pupils are equal and reactive to light.

Posterior: blurred vision, floater

Question 31

treatment of retinitis pigmentosa

Answer 31

supportive
fat soluble vitamins (A, E) ascorbic acid
calcium channel blockers (diltiazem)
carbonic anhydrase inhibitors (acetazolmaide)

AVOID THESE MEDICATIONS: viagra, isotretinoin, high dose vitamin E

Question 32

diagnosis and treatment of 1-day history of blistering rash around the eye with normal visual acuity

Answer 32

Herpes Zoster opthalmicus
Oral aciclovir 800mg five times a day for 7/7

Question 33

cataract is associated with what diseasese?

Answer 33

diabetes
myotonic dystrophy
hpoparathyroidism
rubella

Question 34

what are the 2 causes of retinal artery occlusion?

Answer 34

atherosclerosis - 80% (out of this HTN accounts for 60% and diabetes - 25%)

embolism - 2nd main cause

Question 35

most common cause of blindness in 45-64yo is….?

Answer 35

diabetic retinopathy

Question 36

most common cause of irreversible vision loss in the world is….?

Answer 36

ARMD