Diabetic retinopathy: what is it?

Diabetic retinopathy is referred to when someone is facing retinal damage.

It comes from a diabetes complication due to a destruction of the blood vessels which irrigate the retina. A non-irrigated area then appears; this area is described as being a retina ischemia.

Diabetic retinopathy results in a slow and progressive loss of vision which can eventually lead to total blindness.

Diabetic retinopathy symptoms

At the beginning, no clinical sign helps indicating the potential existence of a diabetic retinopathy.
It will therefore be discovered when undergoing a thorough examination. It is recommended that the patient undergo an ocular check-up as soon as he/she is diagnosed as diabetic, and then once a year.

Diagnosis methods and means
In order to be able to diagnose, various examinations will be carried out:

• a clinical examination made by the ophthalmologist:
- During this examination, timolol will be used so as to obtain a pupil dilation, thus causing a temporary (a few hours) visual efficiency decrease. This is why the patient has to be accompanied by someone who will take him back home after his visit.
- Another anesthetic timolol will be used when positioning the contact lens onto the eye painlessly.
- The ophthalmologist will examine the retina and more particularly, depending on the severity of the retinopathy, potential:
1. Venous dilations,
2. Red dots: scattered and discreet micro-aneurisms and bleedings,
3. Small yellow dots showing exudate,
4. Ischemia areas,
5. Macula thickening and edema,
6. Bleeding patches on the retina,
7. Vascular loops at the front of the retina, indicating a proliferating retinitis,
8. Sometimes, appearance of bleedings inside the vitreous in front of the retina,
9. Looking for possible extension of proliferation retinitis to the iris and for iridocorneal angle invasion, causing a hemorrhagic glaucoma.

Three additional examinations will be carried out:
• A color photograph of the eye fundus will help analyzing as best as possible lesions and will allow for the follow-up of the evolutions via photos comparison,
• a fluorescein angiography which will help visualize retina vessels. It allows for the delineation of the ischemia areas not infused.
• A coherent light retinal tomography (OCT) will help visualize the different layers of the retina.

What are the different categories of diabetic retinopathy?
Diabetic retinopathy consists of two main families, thus allowing to monitor its evolution and to decide which is the best treatment to be applied:

1) Non proliferating diabetic retinopathy which can be minimal, moderate or severe.

2) Proliferating diabetic retinopathy which can be:
non-complicated, with the presence of neovessels,
complicated, with bleedings.

What is diabetic retinopathy’s evolution?
Evolution is slow, over a number of years. Diabetes monitoring is an important factor of diabetic retinopathy evolution.
Visual acuity decrease is dependent on the condition of the macula. It can be sudden when accompanied by retinal-vitreous bleedings.

Puberty, pregnancy, cataract surgery, renal decompensating or high blood pressure may influence its evolution.
Likewise, fixing too rapidly blood glucose level with an insulin pump can, for instance, worsen the retinopathy.
Hence the necessity to monitor eye fundus each year and sometimes even more frequently during these critical periods. GP’s vigilance will ease such a medical monitoring.

How to prevent retinopathy?

The first and main objective is to prevent retinopathy through monitoring diabetes. Such a management is based on a varied and adapted diet and on a regular (even moderate) physical activity in order to optimize blood sugar levels in synergy with the various drug treatments.

Thus, an enhanced diabetes monitoring will limit the risk of potential complications, among which retinopathy.

What is diabetic retinopathy treatment?

When already present, there is no drug treatment but some techniques may help treating it.

- Argon laser or Pascal laser: provides excellent results in terms of neovessels stabilization and suppression.

- Surgery: Vitrectomy can be considered, particularly when intra vitreous bleedings have occurred. Such surgery consists in removing the vitreous, that is to say removing the gel which has filled the eye socket behind the lens/crystalline.


How many people are affected by this disease?
 
- In developed countries, diabetic retinopathy is the primary cause of blindness for people less than 55.
- The prevalence of diabetic retinopathy increases along with the age of the sickness.
- 40 % of diabetic patients develop diabetic retinopathy, which represents around one million people in France.
- People with non-insulin-dependent diabetes 1 develop retinopathy 5 to 7 years after the beginning of the disease. 90 % of patients develop retinopathy after a period of 20 years.

Date: 06/04/2013
Author: Sylvie ERVE
Organization: centich
Reference: http://tpe-malvoyance.e-monsite.com/pages/content/quelles-sont-les-differentes-maladies-oculaires-liees-a-l-age/qu-est-ce-que-la-retinopathie-diabetique.html, http://lmm.univ-lyon1.fr/internat/download/item233b.pdf
Only for Members: No
Content type: Good practises
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Categories: Medical & Functions, Eye - Vision impairment

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