6 - Opth - Retinal disease - Diabetic Retinopathy

Question 1

commonest cause of visual impairment and blindness in who?

Answer 1

working age population

Question 2

What happens (simply)

Answer 2

occlusion +/-leakage in retinal vessels

Question 3

RFs

Answer 3

DM duration
age
smoking
HTN
hyperlipidaemia
poor DM control
renal impairment
pregnancy

Question 4

2 main types

Answer 4

proliferative and non-proliferative - maculopathy can occur with both

Question 5

Non-proliferative DR - symptoms? when occurs? how classified?

Answer 5

• usually aSx - unless maculopathy
• after 8-10y DM
• rated as mild, moderate, severe based on ischaemia degree

Question 6

NPDR - signs

Answer 6

microaneurysms (dots)
haemorrhages (dots/blots - deep in retina, flames - in nerve fibre layer)
hard exudates (yellow patches - leaked lipoproteins from diseased vasculature)
cotton wool spots - retinal nerve fibre layer infarction
vessel dilatation

Question 7

signs of severe NPDR - (pre-proliferative)

Answer 7

large number of dark haemorrhages, irreg vessel dilatation 9beading) and vneous dilatation

most progess from severe NPDR to PDR within 12 months

Question 8

Proliferative DR - more common in which DM? occurs in how many DM pts? characterised by?

Answer 8

T1DM
5%
formation of new vessels on optic disc and retina (neovascularisation)

Question 9

Signs of PDR

Answer 9

new vessels appear initially flat but enlarge and branch irregularly into vitreous (tuffs)

Question 10

Complications of PDR

Answer 10

risk of vitreous haemorrhage
rubeotic glaucoma (due to new vessel growth on iris blocking drainage)
retinal fibrosis -> tractional retinal detachment

Question 11

Diabetic maculopathy- what significantly threatens vision? occurs in? more common in?

Answer 11

Macular oedema
may occur in both NPDR + PDR
more common in T2DM

Question 12

3 types of maculopathy

Answer 12

focal, diffuse, ischaemic

Question 13

Focal maculopathy?

Answer 13

leakage from capillaries in one part of macula -> retinal thickening and surrounding exudates (circinates)

Question 14

Diffuse maculopathy

Answer 14

diffuse retinal oedema from dilated capillaries - maybe ass w haemorrhages but rarely exudates

Question 15

Ischaemic maculopathy?

Answer 15

closure of foveal capillary networks -> diffuse oedema and dark haemorrhage

confirm ischaemia with fluorescein angiography

Question 16

DR management - first principle

Answer 16

control DM and RF’s

Question 17

DR mgmt - laser photocoagulation for?

Answer 17

• PAn retinal photocoagulation in PDR

- focal/grid photocoagulation in maculopathy

Question 18

What can you combine with photocoagulation in maculopathy? what if persistent vitreous haemorrhage?

Answer 18

ANTI-VEGF agents

vitrectomy

Question 19

3 other ocular manifestations of DM

Answer 19

occular palsies (typically III and VI)

recurrent/non-healing corneal ulcers

cataracts