www.diabeticretinopathy.org.uk

Pre-proliferative /non-proliferative retinopathy

David Kinshuck

 

What is pre-proliferative/non-proliferative retinopathy?

In this condition the retina has been damaged by the higher than normal sugar levels over several years. The condition is called 'pre-proliferative' as it usually progresses to develop proliferative retinopathy, when 'new vessels' develop. It is now generally termed 'non-proliferative'.

In severe forms of pre-proliferative retinopathy there are lot of haemorrhages, as the retina is very ischaemic. This needs laser treatment to prevent new vessel growth. Proliferative retinopathy in one eye is especially likely if the other eye has already developed new vessels. It is rarely asymmetric here here. Anti-VEGF treatment may also help..some clinics now have stopped laser and just use Anti-VEGF injections.

In milder forms regular observation is needed to check new vessels do not grow, every 4-6 months. See animation , photo tour  , photos  , Case 15: right Colour photo, red free , Case 39

Small haemorrhages (flecks of blood) and tiny abnormal blood vessels are present. If there are lots of haemorrhages, more than illustrated here, new vessels may grow over the next 12 months, and laser will be needed.
There will be damage to the tiny retinal vessels, such as 'IRMAs' (intra-retinal-microvascular abnormalities). There may be cotton wool spots (areas of retinal damage). p110

 

'Unexpected' deterioration

It is important to control your retinopathy over the long term. However, if your control has been mediocre, and then starts to improve, then the retinopathy may occasionally get worse, and you may need a lot of laser. However, in parts of the world here anti-VEGF injections are available, results are better waiting without laser, and offering injections if macular oedema or proliferation develops.

But after 2-3 years of good control your retinopathy will be better than it would have been otherwise: In the long term good control is crucial, as below. Progression may be rapid, see.

 

Mild pre-proliferative does not need laser/anti-VEGF

Mild pre-proliferative retinopathy does not need laser/anti-VEGF. If your diabetic control (sugar, BP, cholesterol, weight) is good as below, then any progression will be slow. Progression to a more serious type of retinopathy (macular oedema or proliferation) will be much quicker if your control is poor, and such a patient should be examined every 4 months or so.
Also, when a patient with type 2 diabetes changes from tablets to insulin, a rapid improvement in diabetic control may occur, and so such patients may develop a rapid deterioration of their retinopathy.

 

Laser pre-proliferative retinopathy

Moderate or severe pre-proliferative (sometimes called moderate non-proliferative or severe non-proliferative retinopathy) usually needs anti-VEGF (if unavailable) before obvious proliferation develops.

If anti-VEGF injections are not available, PRP laser is indicated. Light subhreshld laser for mild cases is helpful, more severe cases need heavier laser, with slightly greater risk of causing an increase inmacular oedema. (Not all ophthalmologists agre about laser.). There is evidence this reduces the number of vitreous haemorrhages etc later see. Sometimes 2-3 more sessions of laser are needed.

On the other hand, if anti-VEGF injections or laser is delayed, either macular oedema or proliferation develops, and treatment is less likely to prevent visual loss. Sometimes no matter what approach is taken macular oedema develops, but this is much reduced with the anti-VEGF injections or newer laser techniques.

Laser has a 30% chance in increasing in macular oedema, but this risk is much lower if subthreshold laser is used.

Anti-VEGF has not been generally used for pre-proliferative retinopathy, but in future it may be used more often, and will certainly help if there is also macular oedema.

 

Remember the 'targets' for good control

By keeping to these levels as much as possible (or lower still) you will be doing your best to stop your eyes getting worse. Occasionally by sticking to these targets your retinopathy will improve, even without laser. Review BMJ17

 

lifestyle

blood pressure

HbA1c

sudden decrease in HbA1c

cholesterol

smoking

insulin

education

sleep apnoea

glucose level

Glitazones

hypoglycaemia

neuropathy

issues

compliance

type 2 at diagnosis

Photos (details see case 15)

Colour

 

Red free

 

Abbreviations