It is usually carried out in a darkened room in a clinic; anaesthetic drops are placed onto the surface of the eye, a contact lens is placed on the eye, and patients have to sit at a laser slit lamp. This is virtually the same machine as that used for the regular examination, but a laser machine has been added on.

It is naturally uncomfortable having to keep still whilst a doctor flashes a very bright light into the eye.
Each person's treatment is slightly different, depending on the treatment needed.

Maculopathy get get worse even with laser: see PREVENTION OF PROBLEMS. Control of blood pressure and the sugar level is important in the long term, especially for people who are generally well.

Laser light (green) is shone into the eye through a small contact lens, and makes small burns on the retina (blue arrow).
Each bright flash lasts 0.1seconds. The commonest laser is Argon Green,  of wavelength 530nm,  but other wavelengths can be used and most are equally effective.

LASER is simply a highly focused and powerful light, where the light rays are all of the same type.  For this reason it can be pointed at one spot very accurately. Other strong lights were used before laser was introduced.

Laser for maculopathy

This is discussed in more detail under MACULOPATHY. An average of 100 burns are needed, but this varies from very few to 250. This type of laser is not particularly painful, and patients notice a bright slightly painful flash, and maybe slight stinging. The patient will be instructed to look in a certain position at different times.

After each session the sight may be dim or blurred, and this improves over a few days. After the treatment, some people, those with healthier eyes, may notice little black marks in their vision if they look at a white background, and this starts to fade months after the laser.

Treatment may be needed now and again. It can take 3-6 months before for the leakage in the retina to reduce.

The treatment for maculopathy is becoming more aggressive ....the doctor may recommend several laser sessions ...but the results are getting better.

Laser for proliferative retinopathy

The laser is applied the same way, usually through a slit lamp in the clinic. Each treatment is often 1000 burns or more. Much more in one session may cause inflammation of the eye, and too little too little an effect. This type of laser is discussed in PROLIFERATIVE RETINOPATHY in more detail.

The side or 'peripheral' retina is lasered, not the centre; this is the main difference of laser for proliferative retinopathy as opposed to maculopathy above.)

The downside of this treatment includes the discomfort. At first the treatment sessions are unpleasant, with stinging flashes. The sight may be blurred, and the eye may ache for days after the treatment. If the eye still aches after a week, anti-inflammatory drops may be helpful.

After the laser some people notice spots on a white background in their side vision, but this fades (this is the the tiny burns). Other people notice flashes of light at night.

Whilst the laser is need to stop the new vessels growing, the sight is naturally affected slightly. Glare, that is difficulty seeing in sunlight may develop, and difficulties may develop seeing or driving at night.

As time goes on and more laser sessions are needed, the treatment can become extremely painful. There is no entirely effective way of reducing all the pain for such patients, except a general anaesthetic.

Local anaesthetic injections or tablets that aid relaxation may help a little. Sometimes the local anaesthetic injection takes away all the pain, sometimes just reduces the pain slightly. The injection is not into the eye, but under it it at one side.

For patients where the treatment is extremely painful larger departments offer general anaesthetics, as these also have the advantage of allowing laser treatment to both eyes. To do this the department must have a laser that can be used in an operating theatre.

The upside of this laser is that the treatment nearly always works, although several treatments may be needed, and further treatments may be needed over the following months and years. An individual laser session only has a very marginal effect on vision.

A 30year old person with a lot of new vessels may need 6000 laser burns per eye, or even more, to prevent the new vessels growing. Other people usually need less. In patients with very severe disease so much laser may be required that the side vision becomes poor and driving unsafe: the aim of the treatment is to keep good central sight, that is sight looking straight ahead, which is need to read, work, and watch television.

Without laser proliferative retinopathy is often blinding, so both patients and doctors may be left with little alternative to this often unpleasant treatment.

Sometimes laser is needed for pre-proliferative retinopathy: the treatment is similar.