Diabetic eye disease

Question 1

What are the two most common types of diabetic eye disease?

Answer 1

Retinopathy and maculopathy

Question 2

Who does screening for diabetic retinopathy occur in?

Answer 2

All diabetics >12 years old

Question 3

What is the pathogenesis behind diabetic retinopathy?

Answer 3

Fluctuating blood glucose in diabetics leads to damage of the small vessels in the eye. This is due to high blood glucose influencing cell signalling and leading to cell death. This leads to asymptomatic progressive microangiography

Question 4

What are the risk factors for diabetic retinopathy?

Answer 4

Poor glycaemic control
Pregnancy
Long duration diabetes
High LDL cholesterol
Hypertension

Question 5

What are the three complications of microangiopathy causing aneurysms?

Answer 5

Blot haemorrhages form when aneurysms burst
Hard exudate and oedema form from leaking aneurysms
Cotton wool spots are localised infarcts

Question 6

What does a grade of R1 mean?

Answer 6

There will be hard exudates and scattered haemorrhages that do not affect the macula
This is not sight threatening

Question 7

What does a grade of r2 mean?

Answer 7

There is presence of 5 or more cotton wool spots indicating ischaemia
This is sight threatening
There will also be venous changes such as looping and beading
There will be multiple deep, round haemorrhages

Question 8

What does a grade of r3 mean?

Answer 8

This is pre-proliferative retinopathy in which there is new vessel growth
These vessels are prone to bleeding

Question 9

What is diabetic maculopathy (grade M1)

Answer 9

This means that hard exudates and haemorrhages have spread to involve the macula

Question 10

What is a common presentation for diabetic retinopathy?

Answer 10

Gradual painless loss of vision

Haemorrhages can present with sudden onset dark painless floaters

Question 11

What are the three essentials of diabetic retinopathy management?

Answer 11

Optimal glycamic control
Blood pressure
Lipid control

Question 12

How does laser treatment for diabetic retinopathy work?

Answer 12

Photocoagulation (laser) is used to destroy peripheral photoreceptors and reduce oxygen demand and reducing ischaemia.
This causes reduced visual fields

Question 13

What drugs can be given by intravitreal injection to treat maculopathy?

Answer 13

Vegf inhibitors such as bevacizumab used to reduce new vessel growth before laser surgery
Steroid implants (dexamethasone) can be used for retinal oedema but high risk of glaucoma or cataract