Common ophthalmic problems

Question 1

Ocular anatomy

Answer 1

Anterior
-cornea
-iris
-lens
-ciliary body
Posterior
-vitreous
-retina
-optic nerve

Question 2

What do you see when you examine the back of the eye?

Answer 2

Optic nerve
Macula
Retina
Retinal vessels

Question 3

More anatomy**

Answer 3

External - brow
Lids and lashes
Teat ducts and lacrimal glands
The orbit
Nerves and blood supply etc.

Question 4

Muscles of eye movement

Answer 4

6 extra-ocular muscles
-super rectus
-inferior rectus
-medial rectus
-lateral rectus
-superior oblique (torsion)
inferior oblique (torsion)

Question 5

The eye and the brain

Answer 5

The optic nerve is ‘nerve of sight’
-retina converts light energy into electrical impulses that travel down optic nerve to brain for processing (ultimately the occipital cortex)
A problem in brain can interfere with visual processing and also give rise to ‘visual disturbance’

Question 6

Macular

Answer 6

Centre of your vision

Fine point vision

Question 7

Key points about the visual pathway (DIAGRAM)

Answer 7

1. Temporal visual field falls on nasal retina, superior visual field falls on inferior retina and so on…
2. There is cross-over (decussation) of nasal retinal fibres at the optic chiasm
3. The right side of the visual field is represented on the left side of the brain and vice versa

Question 8

A lesion in any part of the visual pathway gives

Answer 8

A particular visual field defect
Armed with this knowledge, you can pinpoint a visual field defect to a particular location in the visual pathway
-right visual field comes to left brain

Question 9

Causes of visual disturbance

Answer 9

Visual disturbance can arise from:

• a pathological process affecting the eye
• a pathological process affecting brain structures involved in visual processing

Question 10

Visual disturbance: history

Answer 10

Need to find out what symptoms the patient is complaining of
Loss of vision
Visual field defect
-central vision
-peripheral Vision
-one eye or both eyes affected
Flashing lights
-migraine
Floaters 
Double vision (diplopia)
Droopy lid (ptosis)
Pupil size inequalities
Is there any pain? Is there headache?

Question 11

Know the signs of a stroke

Answer 11

Balance
Eyes
-disrupts one field of vision?
Face
Arms
Speech
Time

Question 12

Eye causes of visual disturbance

Answer 12

Cataract
Macular degeneration
Glaucoma
Retinal detachment
Eye infections

Question 13

Brain causes of visual disturbance

Answer 13

Stroke (n.b. amaurosis fugax)
Inflammations e.g. optic neuritis (MS)
Migraine
Papilloedema

Question 14

Systemic causes of visual disturbace

Answer 14

Diabetes and diabetic retinopathy
Vessel occlusions and atherosclerosis
Giant cell arteritis
Accelerated hypertension

Question 15

Causes of red eye

Answer 15

Infection
Subconjunctival haemorrhage
Iritis/ anterior uveitis
Acute glaucoma
Scleritis
Ulcer or abrasion

Question 16

Red eye: infection

Answer 16

Conjunctivitis is a very common cause
Most commonly viral (e.g. Adenovirus) but may be bacterial
Vision may be mildly blurred and there is often tears or a discharge
Treatment involves lubricant drops or antibiotic drops if bacterial

Question 17

Red eye: subconjunctival haemmorhage

Answer 17

Can look very worrying to patients
Often spontaneous
Can be linked to trauma
Is the patient on anticoagulants?
Does the patient have a very high blood pressure?
Is there any history of clotting problems?
Can take two weeks to resolve

Question 18

Red eye: iritis/ anterior uveitis

Answer 18

An inflammatory process within the front of the eye
Pain, photophobia
Vision can be decreased
Need referral to eye doctor
Can be linked to conditions like Crohn’s disease, rheumatoid arthritis

Question 19

Red eye: angle closure glaucoma

Answer 19

MUST NOT MISS THIS AS PATIENTS CAN GO BLIND
Often older patients
Very painful red eye, with decrease in vision
Often accompanied by nausea and vomiting
Need urgent referral to ophthalmology
Patients have a high pressure in their eye, which must be lowered before the optic nerve undergoes irreversible damage

Question 20

Red eye: scleritis

Answer 20

An inflammation of the sclera, the tough outer coat of the eye
Associated with an intense pain, often wakes patient from sleep
Requires referral to an ophthalmologist

Question 21

Red eye: ulcer or abrasion?

Answer 21

Corneal abrasion
-very painful
-often due to trauma
-heals within 2-3 days
Corneal ulcer
-very painful
-can be related to contact lens wear
-urgent referral to ophthalmologist

Question 22

Visual loss: cataract

Answer 22

An opacity of the lens
Often due to ageing
Occur earlier in diabetics, trauma, steroid use
Result in a gradual loss of vision

Question 23

Visual loss: macular degeneration

Answer 23

An age related change at the macula
Can be ‘wet’, with new blood vessel growth at the macular area and leakage of fluid
Can be dry, with deposits called drusen found in the macular region
Patients complain of loss of central vision or distortion

Question 24

Visual loss: retinal detachment

Answer 24

The retina becomes detached from the wall of the eye, becoming deprived of the necessary blood supply
Preceeded by flashing lights and floaters
Unless urgently treated by an ophthalmologist, this can progress to permanent, irreversible loss of vision

Question 25

Visual loss: central retinal artery occlusion

Answer 25

Sudden, irreversible loss of vision
Commonly caused by an embolus due to atherosclerosis
Rarely associated with giant cell arteritis (consider if visual loss and headache)
Needs referral to an eye doctor ASAP

Question 26

Visual loss: diabetic retinopathy

Answer 26

Diabetes causes changes in the microvasculature
In the eye, retinal vessels can
-become ‘leaky’, resulting in retinal oedema, most significant if macula affected
-shut down, resulting in retinal ischaemia and new blood vessel growth (neovascularisation), which can then bleed and cause visual loss
Worsening diabetic eye disease is associated with poor diabetic control

Question 27

Visual loss: chronic glaucoma

Answer 27

A painless condition, with elevated eye pressure over a prolongued peroid
Patients asymptomatic until late stage
Optic nerve undergoes progressive damage, resulting in cupped appearance

Question 28

Visual problems and headache: need to consider

Answer 28

Migraine: zig-zag lights, field defects transient history of migraine
Giant cell arteritis: severe headache, scalp pain, jaw pain, pain over temporal artery urgent condition, can cause strokes and bilateral blindness
Papilloedema: raised intracranial pressure can cause optic nerve swelling and visual disturbance