enlarge This is the view
a doctor sees looking into your eye. The small red dots are 'microaneurysms',
tiny damaged capillaries. The bigger red blobs are small haemorrhages, little
flecks of blood. The white dots are exudates (leakage). Your sight is not affected
at this stage.
This is the term given to early damage of the retina in diabetes. Your sight
should be perfectly good at this stage. A doctor examining your eye will notice
tiny abnormalities.
The blood vessel damage is generally visible on photographs. In the UK, nearly
every person with diabetes should have yearly photos taken. In Birmingham these
are taken by about 40 optometrists across the city, but in other places technicians
take the photos, often with mobile cameras. The photographs are examined by
the optometrist or photographer, and patients with significant damage are referred
to hospital clinics. Your pupils have to be dilated for
this examination, and you are often advised not to drive until the pupils have
returned to their normal size.
What the doctor sees
A doctor or optometrist may see 'dots' and 'blots'. The dots are some
capillaries that have enlarged, that is the the tiny blood vessels enlarge
to form microaneurysms.
See photo
tour and photo and photo. The
blots are tiny haemorrhages, that is tiny spots of blood, on the surface
of the retina. There are also leaky areas, called exudates. See photo.
What does it mean if you have 'background retinopathy'?
The number of microaneurysms, the little red dots the doctor sees, indicate
the likelihood of more severe problems in the years to come. See photo. As
the damage is mild at this stage, your sight will be nearly perfect. However,
the condition does progress.
It occasionally progresses quickly, but usually
changes slowly. If your diabetes and blood pressure are well controlled,
and have been all the time you have had diabetes, changes should be very
slow (prevention) are
controlled. Unfortunately for many people with diabetes the retinal damage
increases, and maculopathy or proliferative retinopathy develop over a
few years.
Background retinopathy generally means your diabetes is not controlled
as well as it might be. If you have been diabetic 30 years, even
with the best control, these may develop. But most people who have
background retinopathy have not been diabetic that long, and need
better control as per these targets.
Types & progression of background retinopathy
Retinopathy progression appears to follow different patterns. Some
patients develop leakage (such as macular
oedema), and others develop
capillary closure (which also causes loss of sight). See.
The
number of haemorrhages and microaneurysms indicate progression. If
they increase in number the retinopathy is getting worse. Dropping
blood pressure to the targets above will slow down progression right
away. But if there is significant retinopathy, it takes 3 years of
low blood sugars (eg HbA1c <7.5%, the lower the better) before
good control helps.
Targets
Looking after your diabetes will prevent or delay problems:
The lower the better in macular oedema, as long as you feel well.
An ideal pressure
is below 115 (systolic, first number) for healthy people. <120 is is only suitable for new/well diabetes patients 2012. Otherwise slightly higher as above.
Home
monitoring blood pressures should be 10mmHg (systolic) and 5mmHg (diastolic)
lower see than
these 'clinic' pressures.
HbA1c
7.5-6.5% or
less (see graph) with very few or preferably no hypos. These (or slightly
lower) levels are the best to prevent complications
<7.5 for insulin users; <6.5 if not using insulin and have good
health. Problems with intensive control.
If hypos develop, seek expert
advice from your diabetes nurse/doctor.
if your HbA1c is high (say 11%), then the next step may be to achieve
9%....in other words, and any improvement is helpful, gradually reaching
lower levels above.
sudden decrease
in HbA1c
A
sudden improvement in
control (HbA1c drop of 3%) will lead to a temporary rapid increase
in progression of retinopathy: laser may be needed.
Good control is important
in the longer term, that is after about 2 years. When people who control
their diabetes well will be better off after this period. See
A temporary increase in retinopathy is
most common when starting insulin for the first time, especially if
the diabetes is very badly controlled when you start the insulin.
cholesterol
<4.5 mmol/l, and statins recommended
for most adult patients with diabetes whatever the cholesterol.
statins are recommended whatever the cholesterol,
if well tolerated age>40y
A
fibrate such as fenofibrate may
be advisable in
every person with exudative maculopathy. They reduce retinopathy
progression 40% (Fenofibrate 200mg od) Field
Study. We now recommend these for all adult patients, and
they can be used in addition to a statin.
Insulin pumps generally
produce better control still, but are harder to use.
education
everyone with diabetes should attend
an education course, such as DAFNE (insulin)
, DESMOND (type
2 at diagnosis), or XPERT (type
2). Primary Care Trusts are obliged to send you on such a course, but
very few patients have ever attended one. If you have not been on one,
discuss this with your diabetic team. Get a diabetes buddy.
sleep apnoea
this contributes to macular oedema and loss of sight
(Schwartz, 2006), and many
serious problems.
It is common in
diabetes, particularly if you are overweight. Do you have sleep apnoea?
Rosiglitazone and pioglitazone should not be used
if there is significant retinopathy, and certainly not if macular oedema
is present, as they
increase macular oedema and fluid retention. Case
49. Lirglutadite
and Exenatide are drugs that can be used instead low also lower weight
(they are injections.)
hypoglycaemia
insulin users need to avoid serious hypoglycaemia.
Expert help is usually needed if episodes are severe/frequent. See
many patients receive totally inadequate care BMJ 11. Some call this 'institutionalised neglect'.
Photo
This photograph shows 'circinate' retinopathy. Laser treatment is needed
(early maculopathy). Good diabetic control is needed. Circinates further
from the macula would be classified as 'background' or early none-proliferative
retinopathy.
Circinate retinopathy...good control is needed
to prevent serious eye problems in 3-5 years. There is a circle of exudates
surrounding a leaky area, with a dot haemorrhage or microaneurysm in
the middle. (Case 54)
