Microvascular Complications of Diabetes Mellitus Flashcards
State the three main sites of microvascular complications.
Retinal arteries (retinopathy) Glomerular arterioles (nephropathy) Vasa vasorum (neuropathy)
What factors correlate with risk of microvascular and macrovascular complications?
Glycaemic control (HbA1c)
Hypertension
Other factors such as glycaemic memory and genetics can contribute
Describe the mechanism of glucose damage to blood vessels.
Hyperglycaemia leads to oxidative stress and hypoxia
This triggers an inflammatory cascade, which leads to damage
What instrument is used to look into the eye?
Fundoscope
Where is the optic disc relative to the macula on the back of the eye?
The optic disc is nasal to the macula
What are the 4 types of diabetic retinopathy?
Background
Pre-proliferative
Proliferative
Maculopathy
What three features do you see in background diabetic retinopathy?
Hard exudates
Microaneurysms
Blot haemorrhages
What are hard exudates caused by?
Leakage of lipid contents makes the back of the eye look a cheesy colour
Describe pre-proliferative diabetic retinopathy.
Soft exudates (cotton wool spots) There will be some haemorrhages
What do soft exudates indicate?
Retinal ischaemia
Describe proliferative diabetic retinopathy.
Involves the formation of new vessels (in response to retinal ischaemia)
The new vessels are generally more fragile and can bleed at any time
Describe maculopathy.
Presence of hard exudates in the macula
This is the same disease as background diabetic retinopathy, it’s just that the hard exudates are in the macula
This can threaten direct vision
What are the steps taken in managing background diabetic retinopathy?
Improve blood glucose control
What is the treatment for pre-proliferative and proliferative diabetic retinopathy?
Pan-retinal photocoagulation
Describe the treatment of maculopathy.
You need a grid of photocoagulation in the affected area (aim to limit damage to the macula so you don’t do pan-retinal photo coagulation)