Diabetic Retinopathy

Original article by Jennifer Wood | Last updated on 16/5/2014
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This is the most common cause of blind registration for patients in the UK between 15 and 65 years.
 

Pathology

  • When were they diagnosed with DM- the longer the duration the higher the chance of diabetic retinopathy (80% have retinopathy after 20 years)
  • What is their HbA1c? (the worse the control of DM the higher the chance of retinopathy)
  • Coexisting disease- especially hypertension
  • Smoking
(pregnancy- may accelerate retinopathy)
 
Diabetes causes changes in the retina due to
  • the development of microaneurysms which allow plasma leakage into the retina
  • the development of ischaemic retina
  • the development of AVshunts
 

Symptoms

Non-proliferative retinopathy(background retinopathy)

  • Microaneurysms
  • Dot and blot haemorrhages
  • Cotton wool spots
  • Hard exudates

The vision is usually NORMAL

Proliferative Retinopathy
  • Macular oedema- gradual reduction in vision
  • New vessel growth (neovascularisation)
  • Retinal haemorrhage
  • Vitreous haemorrhage- sudden loss of vision
Vision can range from NORMAL to SIGHT-THREATENING (patients often describe this as sudden black curtain)
 

Examination

Slit-lamp/Ophthalmoscope
Fluorescein angiography (FFA)- to assess damage
Optical coherence tomography (OCT)- to assess if there is any macular oedema
 
Treatment
Macular oedema=focal laser treatment to seal any leaking microaneurysms
In proliferative retinopathy- pan-retinal photocoagulation reduces vaso-proliferative factors and causes regression of new vessels
Macular Ischaemia: NO TREATMENT
Vitreous haemorrhage- vitrectomy
 

Screening

There is a screening programme in the UK- starts 5 years after diagnosis in type 1 dm. Immediately after diagnosis of type 2 DM.  Annual programme of dilated retinal photographs- referred to ophthalmologist if any pathology found. (pregnant DM patients should be examined every trimester)
 

Prevention

  • Optimal Management of DM
  • Optimal management of HTN
  • Smoking cessation (as usual)
  • Encourage to go to screening
 
Key Points:
  • Most common cause of blind registration in younger patients
  • May be asymptomatic
  • Annual Screening and prevention is key
  • Laser and pan-retinal photocoagulation treatment is available in some circumstance