Retina 4 - Diabetic retinopathy

Question 1

What is diabetes and what is the character of Type 1 and Type 2?

Answer 1

•Diabetes leads to high blood sugar levels due to lack of insulin
•Type 1 diabetes
- 10-15% in the uk
- Sudden onset autoimmune attack on islet cells in pancreas
• Type 2 diabetes
- 85%-90% in UK
- Chronic, associated with obesity and age
- Rapidly increasing

Question 2

What is Diabetic retinopathy?

Answer 2

•Raised blood sugar leads to loss of pericytes - Holds blood vessels together
•Capillaries get damaged as a result
- This leads to leakage
- Or blockage
•Leaking capillaries cause maculopathy
• Blocked capillaries cause proliferation
•This results in Ischaemia and proliferate retinopathy

Question 3

DR as cause of blindness - statistics

Answer 3

•Global - 2.6%
•Most common cause of blindness in under 65’s in EU and america

Question 4

Risk factors for Diabetic Retinopathy

Answer 4

•Duration
- Longer have diabetes, greater risk of DR
•Hyperglycaemia
- Poor diabetic controll
• Hypertension
- Poor blood pressure control

Question 5

Features of Diabetic retinopathy (8 in total)

Answer 5

• Micro-aneurysms
•Haemorrhages
•Exudates
•Cotton wool spots
•Venous beading
•New vessels (proliferation)
•Vitreous haemorrhage
• Traction detachment

Question 6

What is Maculopathy associated with diabetes?

Answer 6

•Breakdown of the blood retinal barrier due to loss of pericytes
•Chronic leakage of intravascular fluid
- Exudates
- Oedema
• Reduced VA when fovea affected
• Ischaemic maculopathy is;
- Blocked capillaries around the fovea

Question 7

What causes Proliferate maculopathy? + Leads to?

Answer 7

•Blocked capillaries cause hypoxia
• Ischaemia leads to VEGF production
• New vessels grow on poster vitreous (hyaloid) face
•Leads to severe blindness
- Haemorrhage
- Traction retinal detachment
- Rubeosis (neovascurisation on iris)

Question 8

List the grading Scottish grading scheme
(5 for retina, 3 for macula) and their associations

Answer 8

•R0 - No retinopathy
•R1 - Mild (Microaneurysms)
•R2 - Moderate (up to 4 haemorrhages)
•R3 - Severe (haems, venous bleeding, IRMA)
•R4 - Proliferate

•M0 - No maculopathy
•M1 - Early (Exudates >1 and 2<DD from fovea)
•M2 - Advanced (exudates <1DD from fovea)

Question 9

At what point with the DR grading do you refer?

Answer 9

•R0-R2 : Observe
•R3-R4 : Refer

•M0-M1 : Observe
•M2 : Refer

Question 10

Ophthalmologist Management if proliferate diabetic retinopathy

Answer 10

•Pan retinal laser
- 2-4,000 laser burns to destroy peripheral retina; this reduces VEGF production
• Vitrectomy
- Vitreous haemorrhage
- Traction detachment
• Intravitreal aflibercept injection
- As effective as laser or better
• If eye has maculopathy/ proliferation, injections of anti-VEGF can treat both simultaneously

Question 11

Management of maculopathy + outcome?

Answer 11

•M2 threatening fovea (V/A 6/9+)
- Laser treatment reduces oedema and exudates
- Does not improve VA
• Macular oedema affecting fovea VA <6/12
- Anti-VEGF injections
- Requires repeated injections
- Improves vision by 10+ letters in 50%, 15+ letters in 30%
- steroid implants as second line treatment

Question 12

Management in community

Answer 12

• Remind patients to attend annual screening
• Check fundus in diabetes, with dilation
• Dont refer if R1, R2 or M1
• Refer if R3, R4 or M2
Be aware of undiagnosed diabetes