Ophthalmology - Age-Related Macular Degeneration

Question 1

What is age-related macular degeneration (AMD)?

Answer 1

A progressive condition affecting the macula,

Most common cause of blindness in the UK

Often unilateral, can be bilateral

Question 2

What are the two types of age-related macular degenation?

Answer 2

Wet AMD
10%

Dry AMD
90%

Question 3

What is the macula’s role in vision?

Answer 3

It generates high-definition colour vision in the central visual field

Question 4

List the four layers of the macula

Answer 4

• Choroid layer (contains blood vessels that supply the macula)
• Bruch’s membrane
• Retinal pigment epithelium
• Photoreceptors

Question 5

What are drusen?

Answer 5

Yellowish deposits of proteins and lipids between the retinal pigment epithelium and Bruch’s membrane

A few small drusen can be normal in older patients

Question 6

What can frequent and larger drusen indicate?

Answer 6

An early sign of macular degeneration

Question 7

What features are common to both wet and dry AMD?

Answer 7

• Atrophy of the retinal pigment epithelium
• Degeneration of the photoreceptors

Question 8

What occurs in wet AMD?

Answer 8

New vessels develop from the choroid layer and grow into the retina (neovascularisation)

Vessels can leak fluid or blood causing oedema and faster vision loss

Question 9

What is a key chemical that stimulates the development of new vessels in wet AMD?

Answer 9

Vascular endothelial growth factor (VEGF)

Question 10

List some risk factors for AMD

Answer 10

• Older age
• Smoking
• Family history
• Cardiovascular disease
• Obesity
• Poor diet (low vitamins, high fat)

Question 11

How does AMD present?

Answer 11

• Gradual loss of central vision
• Reduced visual acuity
• Crooked or wavy appearance to straight lines (metamorphopsia)

Question 12

How does wet AMD typically present compared to dry AMD?

Answer 12

Wet AMD presents more acutely and can lead to complete vision loss within 2-3 years

Often progesses to bilateral disease

Question 13

What can be used to easily differentiate between AMD and glaucoma?

Answer 13

Glaucoma is associated with peripheral vision loss and halos

AMD is associated with central vision loss and a wavy apeparance to straight lines

Question 14

What are the key findings on examination for AMD?

Answer 14

• Reduced visual acuity (using a Snellen chart)
• Scotoma (enlarged central area of vision loss)
• Distortion of straight lines (Amsler grid test)
• Drusen seen during fundoscopy

Question 15

What is Slit lamp examination used for in AMD?

Answer 15

Detailed view of retina and macula

Question 16

What is the purpose of optical coherence tomography in AMD?

Answer 16

To give a cross-sectional view of the layers of the retina for diagnosis and monitoring

Question 17

What does fluorescein angiography assess in AMD?

Answer 17

Blood supply, showing oedema and neovascularisation in wet AMD

Question 18

What is the management for dry AMD?

Answer 18

Monitoring and reducing the risk of progression
- Avoid smoking
- Controlling blood pressure
- Vitamin supplementation

Question 19

What medications are used to treat wet AMD?

Answer 19

Anti-VEGF
Ranibizumab
Aflibercept
Bevacizumab

Injected directly into vitreous chamber once a month

Question 20

What does VEGF do?

Answer 20

Vascular endothelial growth factor

Stimulates new blood vessel development in the retina

Question 21

What is the frequency of intravitreal injections for wet AMD treatment?

Answer 21

Usually about once a month