Unit 6: Differential Diagnosis of Blurred Vision
Diabetic Retinopathy
Aetiology
- Hyperglycaemia is the main cause of micro vascular complications, including retinopathy.
- The clinical signs are caused by small blood vessel occlusion, increased vascular permeability and changes in blood vessel walls from loss of supporting pericytes.
- New vessels at the disc (NVD's) [see image] occur in proliferative diabetic retinopathy in response to vascular endothelial growth factors, released in response to retinal ischemia.
NVDs: new vessels at the disc
Source:
- Signs of diabetic retinopathy are often detected during retinal screening, before symptoms.
- Vision loss is usually caused by maculopathy or vitreous haemorrhage.
- Maculopathy initially can present with slight central visual loss but is often progressive.
- Vitreous haemorrhage often causes acute loss of vision, or floaters in the field of vision.