Macular Degneration

Question 1

What are the two types of macular degeneration?

Answer 1

Wet and dry

Question 2

What kind of vision is lost with AMD?

Answer 2

Central vision as the macular is involved

Peripheral vision is maintained

Question 3

What is the most common cause of blind and partially sighted registration in the elderly?

Answer 3

Macular degeneration

Question 4

What are the symptoms of AMD?

Answer 4

Gradual loss of central vision
Often very slow progression- but Wet AMD can cause vitreous haemorrhage which is a cause of acute painless visual loss.
Distorted central vision

Question 5

Which is the most common form of AMD?

Answer 5

Dry form

Question 6

What is the precursor lesions in dry AMD? What are the two types?

Answer 6

Drusen are the pre-cursor lesions. There are two types-
Hard Drusen- Round yellow with well defined boundaries
Soft Drusen- (Cause AMD) soft boundaries, grow and come together

Question 7

What is the underlying pathology of wet AMD?

Answer 7

Characterised by choroidal neovascularisation- There is formation of abnormal blood vessels beneath the retinal pigment epithelium (RPE) layer of the retina.

These penetrate into the retina and macular region and cause bleeding

Bleeding causes scarring which causes visual loss- forms circular scars called disciform scars

Question 8

What type of scar is produced in wet AMD?

Answer 8

Disciform Scar- this is end stage. Produced due to bleeding underneath the retina. Scar is underneath the retinal as blood vessels can be seen overlying it.

Question 9

What is the process under-pinning wet AMD?

Answer 9

Choroidal neo-vascularisation- this is blood vessel formation in the choroid which is found beneath the retina and the retinal pigment epithelium

Question 10

What are drusen made up of?

Answer 10

Yellow, lipid deposits.

There are hard and soft drusen. Soft drusen are problematic.

Question 11

What change is seen with dry AMD?

Answer 11

Soft drusen come together leading to Geographic Atrophy

Question 12

What are soft drusen a sign of?

Answer 12

Early dry AMD

Question 13

What growth factor stimualtes choriodal neovascularisation?

Answer 13

VEGF

Question 14

What are some strong risk factors for AMD?

Answer 14

Increased age
Smoking
Family History
Genetic- Complement Factor H Gene

Question 15

What is the treatment for dry AMD?

Answer 15

Little treatment available
Low vision aids such as magnifying glasses
Vitamins- in in patients with advanced AMD in one eye- high dose zine and anti-oxidant vitamins help prevent deterioration in other eye
Severely sight impaired registration (Think social reasons)

Question 16

What is the treatment for Wet AMD?

Answer 16

Anti-VEGF Injections

e.g. Avastin, Aflibercept (eylea), Ranibizumab

Question 17

What can be used measure the thickness of the retina?

Answer 17

OCT Scanning- Optical Coherence Tomography (non-invasive). OCT can image the deeper layers of the retina and investigate for the development/early signs of macular degeneration (CNV and drusen formation).

Early intervention-= better outcomes with wet AMD

Question 18

What type of scanning can be used to image the structures of the back of the eye in detail?

Answer 18

OCT scanning