everyone with diabetes develops a complication, many people have a very mild
form of retinopathy which may never progress to a sight threatening condition.
most serious complication of diabetes for your eye is the development of
diabetic retinopathy. Diabetes affects the tiny blood vessels of your eye and
if they become blocked or leak then your vision may be affected. Forty per cent
of people with type 1 diabetes and 20 per cent with type 2 diabetes will
develop some sort of diabetic retinopathy.
Background diabetic retinopathy
is the most common type of diabetic retinopathy. The blood vessels in the
retina bulge slightly (microaneurysm) and may leak blood (haemorrhages) or
fluid (exudates). As long as the macula is not affected, vision remains normal and you will not be aware that anything
is wrong. Your retinal screening test will check for these early changes and monitor
for any signs of progression
Proliferative diabetic retinopathy
diabetic retinopathy progresses, it can cause the blood vessels in the retina
to become blocked. These can result in areas of the retina becoming starved of
oxygen. (ischaemia) and the eye is stimulated into growing new vessels, a process
these new blood vessels are weak, and grow in the wrong place - on the surface
of the retina and into your vitreous gel. These blood vessels can bleed very
easily and result in large bleeds over
the surface of the retina or into the vitreous gel.
can totally obscure vision in the affected eye as the blood blocks light. For
many people, with time, the blood can be reabsorbed and their sight can
improve. But for others these bleeds may keep happening and can lead to
permanent loss of sight.
bleeding can lead to scar tissue forming which distorts the retina resulting in
a tractional retinal detachment with the risk of blindness.
10 per cent of all people with diabetes develop proliferative retinopathy.
maculopathy may occur either with background, or proliferative retinopathy. If
this happens, your central vision will be affected and you may find it
difficult to see detail such as recognising people's faces in the distance or reading
the vision that allows you to get around at home and outside (peripheral
vision) is not affected.
diabetic maculopathy can be treated with a laser, and more recently injections,
with the aim of preserving as much vision as possible, although vision may
improve in 25% of treated eyes.
diabetic control significantly lowers your risk of retinopathy.
following actions reduce your risk of developing retinopathy or help to stop it
from getting worse:
Controlling your blood sugar (glucose levels).
Tightly controlling your blood pressure.
Controlling your cholesterol levels.
Keeping fit, maintaining a healthy weight and giving up
smoking are all part of good diabetes control. Nerve damage, kidney and
cardiovascular disease are more likely in smokers with diabetes.
Regular retinal screening. Early detection and treatment
prevents sight loss.
factors that cannot be controlled:
The length of time you have had diabetes. This is a major
risk for developing diabetic retinopathy.
Your age affects the progression of diabetic retinopathy.
Your ethnicity. If you or your family are from India,
Pakistan, Bangladesh or Sri Lanka you are more at risk of developing diabetes
and the sight-threatening complications.
you have diabetes and plan to have a child, retinal screening is carried out
more often during pregnancy and for a while after you have had your baby.
Annual diabetic eye screening
of the complications that diabetes causes in the eye can be treated, but it is
vital that they are diagnosed early. If you have diabetes you will have annual
retinal screening. A picture
is taken using a digital retinal camera and this is looked at in detail to see
if there are any changes caused by diabetes.
retinopathy is identified early, through retinal screening, and treated
appropriately, blindness can be prevented in 90 per cent of those at risk.
Treatment for diabetic retinopathy
sight-threatening problems caused by diabetic retinopathy can be managed by
laser treatment if detected early enough. The aim of laser treatment is to
prevent bleeding or to prevent the growth of new blood vessels. The laser can
be used in two ways:
Focal Laser Treatment
individual vessels are leaking, laser treatment can seal them. This type of
treatment is quick, painless and performed in the outpatient clinic, sometimes
taking only a few minutes. Vision is not affected by this type of treatment.
Pan retinal Laser Treatment
new vessel growth (neo-vascularisation) has been detected you may need more
extensive laser treatment. The aim is to treat the peripheral retina with the
laser. This treatment stops the retina from producing the growth factors that
stimulate new blood vessels to grow. Treatment causes the new vessels to shrink
and disappear over a few months.
treatment is identical to focal laser but may be divided into a number of
sessions as treatment time is significantly longer
new vessels are first detected your vision may still be very good. After the treatment
your peripheral vision may be affected. You may feel that the laser has made
your sight worse. The difficult issue is, that if left untreated, the new
vessels will soon bleed and cause serious loss of vision. The laser treatment
is the best option for preventing this.
is important to remember that laser treatment aims to prevent your vision from
getting worse. It cannot make your vision better.
How is treatment carried out
can usually be treated in an outpatient clinic and do not need to stay in
hospital. Eye drops enlarge your pupils so that the eye specialist can look
into your eye.
eye is then numbed with drops and a small contact lens is put onto your eye to
stop it blinking.
treatment is first suggested, ask how long each session is likely to last. Some
people need more than one treatment session.
Is it painful
treatment for sealing blood vessels does not usually cause discomfort. Pan
retinal treatment can be uncomfortable, so you may need a pain-relieving tablet
at the same time as the eye drops:
tell your eye specialist if the treatment is hurting
tell the eye specialist if you have found a previous session
of laser treatment uncomfortable.
Does laser treatment have any side effects
treatment is possible without some side effects, but the risks to your vision
of laser treatment are far fewer than the risks of not having laser treatment.
short-term effects of the laser treatment are due to the brightness of the
laser used. It can cause a temporary reduction of sight which may last an hour
or two after the treatment. You may also lose a little central vision which may
improve with time or notice the after effects of the laser as small black spots
in your vision.
local treatment has little long-term effect, as it only treats a very small
area of the retina.
more extensive pan retinal treatment can have more lasting effects on your
It is quite common to lose some vision to the sides
(peripheral vision) and this may affect your ability to drive safely.
Night and colour vision may also be affected.
Occasionally your central vision may not be as good as
before so that, for example, print is not as easy to see.
you drive and have had laser treatment in both eyes or your one remaining eye
you must inform the Driver and Vehicle Licensing Agency (DVLA). They may ask
that you have an examination to make sure your central and peripheral vision are
good enough for safe driving.
What if my eye becomes painful after treatment, or if my vision gets
lengthy treatment, some people may develop a headache, paracetamol can be
taken for this.
if the pain is severe, or if your eyesight gets worse, you should contact your
eye specialist immediately.
If this is not possible, go straight to the
Accident and Emergency department at your nearest hospital.
Treatment for diabetic macular oedema
can cause fluid to collect on or under your macula which is known as
"oedema". Macular oedema may make your central vision distorted or blurry and, over a
period of time, it may cause a blank patch in the centre of your vision.
the macular oedema does not involve the centre of the macula (called fovea),
laser treatment can reduce the leakage and prevent any more blurring. However,
when the oedema affects the centre, then laser treatment offers no benefit.
is now available for this type of diabetic macular oedema.
an anti-vascular endothelial growth factor (anti-VEGF) treatment. Research has
shown that Lucentis can reduce the macular swelling caused by diabetic macular
oedema, and reduces the blurred central vision.
is given by an injection into the white of your eye and you may need to have
more than one injection over a period of months to get the best effect.
Other ways diabetes can affect your eyes
changes in blood sugar levels resulting from diabetes can affect the lens inside
your eye, especially when diabetes is uncontrolled. This can result in blurring
of vision which comes and goes across the day. This blurring may be one of the
first symptoms of diabetes although it may also occur at any time when your
diabetes is not well controlled. Once your diabetes is controlled most people
find this variable blurring goes away.
cataract is a clouding of the lens of your eye,
which causes the vision to become blurred or dim because light cannot pass
easily to the back of your eye. This is a very common eye condition that develops as we get older, but people with
diabetes usually develop cataracts at an earlier age.
Important points to remember
Early diagnosis of diabetic retinopathy is vital.
Attend your annual diabetic eye screening appointment.
Speak to your doctor if you notice changes to your vision.
• Sight-threatening diabetic problems can be
managed by laser if treatment is early
Good control of sugar, blood pressure and cholesterol
reduces the risk of diabetes-related sight loss.
Smoking increases your risk of diabetes-related sight loss.