Complications of Diabetes

Laser Treatment

Laser treatment


This leaflet tells you about laser treatment and will give you an overview of having laser treatment at our hospital.

How does retinopathy cause loss of sight?

  • Leaky blood vessels on the retina cause fluid to seep into layers of the retina. This results in swelling (oedema) of the retina with resulting deterioration of vision. There are times when this fluid may be absorbed spontaneously and it may not cause permanent loss of vision. If it is likely to progress and cause further damage, laser treatment is advisable. This condition is known as diabetic maculopathy.
  • When damage to blood vessels is severe, they attempt to regrow, a process known as ‘neovascularisation’ (new vessel formation). This condition is referred to as proliferative retinopathy. These new blood vessels are very fragile and may rupture casuing bleeding into the sight sensitive layers of the retina. This may results in dramatic visual loss.

What is the purpose of laser treatment ?

The purpose of laser treatment is to preserve sight. It is therefore  important that treatment is administered early, before there is significant visual loss. This is why regular eye screening is so important. Laser treatment seals off the fragile new blood vessels preventing leakage of fluid and blood.

How do lasers work?

Laser is a special type of high energy light which can be accurately focused. This light can be precisely controlled allowing the operator to ‘zap’ tiny blood vessels at the back of the eye. The patient is seated at a slit lamp which allows the ophthalmologist to see the area being treated.

What conditions are suitable for laser therapy?

  • Diabetic macular oedema
  • Proliferative diabetic retinopathy

How long does this take?

Often laser therapy involves hundreds of small laser burns which may need to be applied over several sessions.

Do I have to be admitted to hospital?

No. This is an outpatient procedure.

Is the procedure painful ?

Not always. Some patients may require a local anaesthetic.

Can my vision get worse?

Yes. A small proportion of patients may actually suffer a deterioration of vision. Loss of peripheral vision is more likely.

What are the side effects of laser treatment ?

Side effects of laser therapy are rare but may include

  • Corneal burns and scars
  • Cataract
  • Glaucoma
  • Rupture of blood vessels with bleeding
  • Vitreous haemorrhage

Your ophthalmologist will advise you on the potential risks which would depend on the extent of retinopathy in your eyes.


Dr Nishan Wijenaike
Consultant Physician
West Suffolk Diabetes Service
May 2003