PANRETINAL PHOTOCOAGULATION FOR ADVANCED RETINOPATHY

What is panretinal photocoagulation (PRP) laser?

Panretinal Photocoagulation (PRP) is a type of laser treatment for the eye.  It is typically used in advanced stage of diabetic eye disease as well as conditions that can affect the blood supply to the retina (such as retinal vein occlusion)

Why do I need panretinal photocoagulation laser?

The PRP laser treatment stops abnormal vessels on the retina and in the drainage system of the eyeball from growing and encourages existing ones to shrivel up.  This makes them less likely to cause a bleed into the jelly in the eye (vitreous haemorrhage) or to cause a painful type of high pressure within the eye (neovascular glaucoma).

In patients who have developed new blood vessels in the coloured part of the eye (iris) due to a blocked vein in the eye (central retinal vein occlusion) there would be a risk of developing a painful eye due to blockage of the fluid inside the eyeball caused by growth on new blood vessels in the eyeball.  In this case the aim of the treatment is not to prevent loss of vision as there will already be very poor vision that cannot be improved due to the existing damage. The aim is to prevent the eye becoming painful through a build-up in fluid in the eye raising the pressure in the eyeball.

Can there be any side effects or risks?

There is good scientific evidence that laser treatment will significantly prevent the risk of your vision deteriorating. It also reduces the risk of the eye developing painful high pressure.

Possible side effects and risks of the treatment include:

• Reducing the peripheral (edge) field of your vision - You may not notice the effect of this.  However it might mean you will not meet the visual legal requirements for holding a driving license, particularly if both eyes need treatment.  You will need a visual field test following after the laser treatment.  Ask your eye specialist about this if you are a driver. 

• Your night vision may be reduced and your colour vision altered in the eye having the treatment.

• Rarely your central vision may be worse after the treatment. This can be caused by a build up of fluid at the back of the eye (macular oedema), bleeding within the eye (vitreous haemorrhage) or very rarely by an unintended burn to the centre of the retina. Rarely this deterioration of vision may be permanent.

How do I prepare for the panretinal photocoagulation laser?

• It is essential that you do not drive to and from your appointment as you will be having dilating drops in the eye under-going treatment. These drops will blur your vision for up to 6 hours after the treatment.

• You may eat and drink normally unless you have been advised not to do so.

• If you have diabetes you should have your normal meal and medication before the procedure and have some snacks with you while you wait. 

• Share the information on this page with your partner and family (if you wish) so that they can be of help and support. There may be information they need to know, especially if they are taking care of you following this examination.

 

What will happen?

• This treatment is performed in the laser treatment room of our clinic.

• A nurse/assistant will check your vision and instill some eye drops to dilate the pupil. These drops will blur your vision for 4-6 hours. These drops are to allow the doctor to see the back of your eye when carrying out the laser treatment.

• You will be asked to sign a consent form for the treatment and specific risks to your eye condition will have previously been discussed with you.

• PRP laser treatment involves applying many laser burns to the edge of the retina (the neural tissue on the back of the eyeball).  This is often done over a number of different sessions.

• You will be shown into the room where the laser treatment is to be carried out.

• A local anaesthetic drop or injection may be used before the laser treatment is given.

• The laser is applied with a microscope with a chin rest similar to the one used in clinic to examine your eyes and a special contact lens.

• The treatment usually takes 15-30 minutes depending on how much treatment is required in your particular circumstance.

• During the treatment you may notice some mild pain associated with the laser spot.  If so, let your eye specialist know and he/she will reduce the power of laser accordingly.  Rarely if there is excessive pain you will be given local anaesthetic with special needle around your eye to completely numb your eye for the procedure.

• It is relatively common for some patients to feel a bit faint during the procedure because of the light being shin into the eye.  If you feel faint or queasy then tell your eye specialist to stop and you can take a rest before deciding to continue the treatment.

What happens afterwards?

• Following the treatment you can go home.

• You may notice discomfort or a dull ache in the eye after the treatment. This can be helped by taking painkillers as you would for a headache (e.g. Paracetamol).

• Your vision will be “dazzled” or may seem darker after the treatment. This effect can last for 24-48 hours.

• You should avoid driving for 24 hours after the treatment.

• A follow up appointment will be arranged for either a further session of PRP laser (if required as part of a course of treatment) or for a follow-up check in a few weeks to check that the eye is responding to the treatment. This varies depending on the reason you are having the laser treatment for.

• It may be necessary for further treatment to be carried out.

• If you have any concerning symptoms you can contact our clinic and our staff will provide you with advice on what to do.  If this happens out of hours or during public holiday you can contact the emergency at Royal Victorian Eye and Ear Hospital on (03) 9929 8666.

Should you require further advice on the issues contained in this leaflet, please do not hesitate to contact our staff.