Opthalmoscopy

Question 1

What causes an absent red reflex?

Answer 1

Retinal blastoma
Retinal detachment
Cataract

Question 2

How can a relative afferent pupil defect be picked up?

Answer 2

Swinging light test
- When light is shone on abnormal eye, the pupil appears to dilate, as there is reduced input to the brain from the abnormal eye, so both pupils dilate in the face of light being moved away from the normal eye

AKA Marcus Gunn

Question 3

How can an efferent pupil defect be picked up?

Answer 3

Shine a light in one eye and it only causes contralateral constriction

Question 4

What is anosocria?

Answer 4

Unequal pupil sizes - can be harmless

Question 5

What is a cataract?

Answer 5

Painless opacification of the ocular lens due to buildup of protein and pigment, leading to gradual visual loss

Question 6

A patient has decreased visual acuity, which improves after using a pinhole. What is the diagnosis?

Answer 6

Cataract (pinhole removes aberrations of light)

Question 7

What is a Holmes-Adie pupil?

Answer 7

Large pupil that is slow to constrict to light - this can be normal

Question 8

What causes cataract?

Answer 8

Congenital - intrauterine infection
Diabetes
Steroids
Age
Radiation therapy

Question 9

What is a nuclear cataract?

Answer 9

Yellow/browning on centre of lens - associated with glare and myopia

Question 10

What is a cortical cataract?

Answer 10

Wedge-like opacity that starts at the peripheries and works towards the centre

Question 11

What is a sub capsular cataract?

Answer 11

Occurs at the back of the lens - associated with diabetes and steroids

Question 12

How are cataracts managed?

Answer 12

• PHACOEMULSIFICATION - Ultrasonic device is used to break up and remove the cataract
• SURGERY - put artificial lens in, which doesn’t have the ability to accommodate

Question 13

What is glaucoma?

Answer 13

Optic nerve change associated with raised intraocular pressure and associated visual field loss.

Characterised by optic disc changes

Question 14

What is the pathology behind glaucoma?

Answer 14

1. Problem with ocular drainage system

2. Excessive production of aqueous humour

Question 15

What produces aqueous humour?

Answer 15

The ciliary body (also involved in accommodation)

Question 16

What is open angle glaucoma and what are the RFs?

Answer 16

Reduced drainage of aqueous humour due to dysfunctional meshwork

RF: family history, trauma, age, steroids, race (african)

Question 17

What is closed angle glaucoma?

Answer 17

Acute onset increased ocular pressure causing red eye, visual loss, vomiting, pain and seeing halos around lights. In this case the angle is completely closed, and no aqueous humour can leave

RF: asians, small eyes, big cataracts

Question 18

What is golden application tonometry?

Answer 18

A machine used to measure intraocular pressure (in glaucoma for example)

Question 19

What is the normal intraocular pressure?

Answer 19

10-20mmHg

Question 20

What does a normal optic disc look like?

Answer 20

• Creamy pink colour
• Cup with small round central depression
• Symmetry between both eyes
• Well-defined edges

Question 21

What is optical coherence tomography?

Answer 21

Imaging used to look at the retina and quantify optic nerve fibre loss

Question 22

What is perimetry?

Answer 22

A visual field test which can pick up arcuate scotoma, caused by glaucoma

Question 23

How is glaucoma managed medically?

Answer 23

Reduce aqueous humour production

• Topical b-blockers (timolol)
• ACE inhibitors (dorzolamide)

Increase fluid outflow

• Prostaglandin analogues (-prost these cause eyelash growth)
• Miotic agents (pilocarpin)

Dual mechanism
- Alpha agonists (-onidine)

Question 24

How is glaucoma managed surgically?

Answer 24

Create a new drainage pathway:

• laser surgery
• trabeculectomy
• canaloplasty
• glaucoma implant devices

Question 25

What are the stages of diabetic retinopathy?

Answer 25

Non-proliferative - dots, blots and exudate
Pre-proliferative - cotton wool spots, venous bleeding, looping
Proliferative - neovascularisation
End-stage - retinal detachment

Question 26

Why do you get neovascularisation in proliferative retinopathy?

Answer 26

Microvascular changes cause occlusion and ischaemia. This stimulates the body to produce growth factors which lead to neovascularisation

Question 27

Why do you get cotton wool spots in pre-proliferative retinopathy?

Answer 27

Loss of pericytes causes leakage and exudate.

Question 28

What is maculopathy?

Answer 28

Retinopathy at the macula, causing exudate haemorrhages and micro-aneurysms

Question 29

How is diabetic retinopathy managed?

Answer 29

• Pan-retinal photocoagulation
• Anti VEGF injections
• Focal laser (scars retina to reduce neovascularisation)
• Surgery

Question 30

What is a side effect of focal laser treatment?

Answer 30

It causes visual field loss as you are scarring the retina

Question 31

What are the features of hypertensive retinopathy?

Answer 31

AV nipping
Copper/silver wiring (hardened arteries)
Cotton wool spots
Flame haemorrhage
Papilloedema

Question 32

How is hypertensive retinopathy treated?

Answer 32

Get BP down below 140/90

Question 33

What is strabismus?

Answer 33

Squint

Question 34

What is:

a) esotropia?
b) exotropia?
c) hypertropia?
d) hypotropia?

Answer 34

a) squint inwards
b) squint outwards
c) squint upwards
d) squint downwards

Question 35

What would cause esotropia/hypertropia?

Answer 35

Esotropia - 6th nerve palsy

Hypertropia - 4th nerve palsy