Diabetes: Diabetic complications Flashcards
Describe why diabetic complications occur [3]
Long term exposure to hyperglycaemia:
- causes mircroaneurysms and venous beading (where the walls of the veins are no longer straight and parallel and look more like a string of beads or sausages)
- vessel closure: hypoxia & nutrients decreased
- vessel permeability: damaged vessels dilate and leak
Which is the strongest risk factor for diabetic complications? [1]
Name 3 others [3]
1st: Smoking
2nd: HTN
3rd: Dysplidaemia
4th: Hyperglycaemia
Describe the pathophysiology of diabetic retinopathy [3]
Chronic hyperglycemia causes:
- basement membrane thickening
- loss of pericytes
- endothelial cell damage in retinal blood vessels (microaneurysms & venous beeding
Describe the three classifications of diabetic retinopathy? [2]
non-proliferative diabetic retinopathy (NPDR) marked by:
- microaneurysms
- retinal haemorrhages (dot haemorrhages)
- hard exudates (yellowish deposits of lipid due to vessel leakage)
proliferative diabetic retinopathy (PDR) (more advanced and severe stage), is characterized by:
- the proliferation of new, fragile blood vessels that can bleed into the vitreous, leading to vision loss due to VEGF upregulation
- can be new vessels on disc (NVD) OR new vessels everywhere (NVE)
Diabetic maculopathy:
- Presence of any retinopathy within 1 disc diameter around macula:
Can be:
- Focal
- Diffuse
- Ischaemic
How can you prevent diabetic retinopathy? [3]
Good BP control - most important
Good glycaemic control
Annual screening
What are the different types of classification of hard exudates in non-proliferatve retinopathy? [3]
Mild
Moderate
Severe: Cotton wool spots (arrow): areas of retinal ischaemia
What does this yellow arrow depict in non-proliferative diabetic retinopathy? [1]
Hard exudates
What does the yellow arrow on the image of non-proliferative retinopathy depict? [1]
Lipid exudates
Describe what the arrows & circle depict on this image of non proliferative diabetic retinopathy [3]
intraretinal microvascular abnormality (IRMA; green arrow)
venous beading and segmentation (blue arrow)
cluster haemorrhage (red circle)
featureless retina suggestive of capillary non-perfusion (white ellipse)
What is the arrow pointing to on this NPDR? [1]
Cotton wool spots (severe NPDR
How can PDR lead to blindness? [4]
- New blood vessels are very fragile; easily break and leak
- Retinal haemorrhage can lead to acute blindness
- If repeated; leads to fibrosis & scarring
- Can lead to: tractional retinal detachment: when scar tissue or other tissue grows on your retina and pulls it away from the layer underneath
Which pathology is depicted? [1]
Diabetic maculopathy: hard exudates near to the macula
What is depicted in this image? [1]
Proliferative diabetic retinopathy:
extensive vitreous haemorrhage obscuring most of fundus (white circle)}
What is the arrow pointing to? [1]
Cotton wool spot
What is depicted in this image? [1]
Non-proliferative diabetic retinopathy: blot haemorrhage (white circle)}
Describe what is happening in this image [1]
Proliferative diabetic retinopathy: NVD new vessels on the optic disc
What is the management of diabetic retinopathy? [5]
Laser photocoagulation
Anti-VEGF medications such as ranibizumab, bevacizumab & Aflibercept
Vitreoretinal surgery (keyhole surgery on the eye) may be required in severe disease or a vitrectomy may be necessary to clear severe vitreous hemorrhage or to relieve tractional retinal detachment.
Corticosteroids (triamcinolone, dexamethasone implant) can also be used, particularly in refractory DME.
Pan-retinal photocoagulation (PRP): laser used to make small burns evenly across the peripheral retina - should make blood vessels shrink and dissapear
What are the different types of diabetic neuropathy? [5]
- Periperal sensory neuropathy
- Autonomic neuropathy
- Proximal motor neuropathy (amyotrophy; femoral nerve neuropathy - severe pain in anterior thigh & quadricep wasting)
- Cranial nerve palsies (CN III, VI & VII)
- Median nerve / Carpal tunnel syndrome
Which cranial nerves are particularly effected by diabetes? [3]
Cranial nerve palsies: CN III, VI & VII
Describe the distribution for peripheral sensory neuropathy [1]
Glove and stocking distribution