to treat diabetic retinopathy
- VEGF = vascular endothelial growth factor
- IVA = Intravitreal Avastin
There are 3 drugs. Eylea is new and longer lasting and is likely to be the best for the moment, Avastin is the cheapest and almost certainly just as good as Lucentis which is in popular use. The procedure is discussed.
The drugs reduce macular oedema and proliferation (blood vessel growth) in diabetic retinopathy, but their effect usually wears off. To keep good sight in the long term, the diabetes and blood pressure (BP) must be controlled: the drugs are very useful for use whilst patients are trying to control their diabetes and BP
The risk of anti-VEGF treatment is small
- 1/1000 serious infection
- Small risk of other less serious problems such as cataract and retinal tears.
How are AntiVEGFs given
The AntiVEGFs are given by injection into the vitreous cavity of the eyeball details. The drugs last 4-8 weeks. There are different protocols.
- see details
- Lucentis/Avastin 3 injections a month apart, then monthly OCT examinations, and if the macular oedeam re-accumulates, then inject 2-3 times and continue. After the 3 loading injections, no injections needed if there is no oedema.
- is not yet in regular use for diabetic retinopathy, but would probably be used at the similar time intervals.
- AntiVEGF injections started early will maintain good vision; the treatment is very helpful. (Although for good sight without injections good diabetic control, low blood pressure, not smoking, health diet, are all essential. Injections need to be started early before severe macular oedema develops, and with follow up and repeated injections, and occasional laser, the retina can remain dry without leakage or new vessels.
So in addition to good diabetic control, we need to continue to detect retinopathy early, and start injection treatment early.
Funding for AntiVEGF
- is available across the UK for Lucenti sifor diabetic mcaular oedema. Avastin would be much mcuh cheaper, and Eyelea may last longer. Laaser may help some patients if used as well.
- There is funding in some units for their use in proliferative retinopathy. They are best used in
Repeated AntiVEGF injections
Unfortunately the effect of these drugs is just weeks. Here is my interpretation of Macugen's (an older drug now withdrawn)
Visual acuity improved whilst the injections are given, but starts to deteriorate
when they are stopped. However, if the blood pressure is lowered aggressively
and diabetic control improves, ophthalmologists hope for much longer benefit.
All these are injections in the eyeball itself, all with a rrisk of glaucoma. Triamcinolone is a regular fluid injection, heOsardex and illuvian are slow-release inserts.
- triamcinolone is useful for short term use, partiucaly for post=cataract macular oedema. There is a conderable risk of glaucoma, see details
- Osardex helps, but 100% patients develop catarcts, and there is a considerable glaucoma risk, Details.
- illuvien is licencsed for use after the cataract has been removed, details
Somatostatin in retinopathy
Previous reports indicated that this drug would be helpful see ,
but there are few reports other than
case reports. More recent reports indicate no long term benefit. They have been replaced by AntiVEGFs.
Good control of diabetes
This is essential even with the new drugs. See targets