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.
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.
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
Mild pre-proliferative retinopathy does not need laser. 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, and early laser is best.
Laser pre-proliferative retinopathy
Moderate
or severe pre-proliferative (sometimes called moderate non-proliferative
or severe non-proliferative retinopathy) usually needs laserbefore obvious
proliferation develops.
The first laser in such a patients is usually a light
macular grid laser. This is followed by gentle PRP laser
at a later session, perhaps 2 weeks later. In very aggressive cases
laser (grid and PRP laser) must be simultaneous.
There is evidence this reduces the number of vitreous haemorrhages
etc see.
Sometimes 2-3 more sessions of laser are needed.
On the other hand, if 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 newer laser
techniques. In a straw poll in 2005 50% of UK and 80% of EASDec members
laser pre-proliferative retinopathy, and do not wait for loss of sight
caused by macular oedema or the risk of bleeding etc with frank proliferation.
Heavy laser in such a patient is likely to cause macular
oedema, but it can develop even with lighter laser.
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.
lifestyle |
- 30-120
minutes exercise a
day ,
- moderate alcohol consumption only,
- avoid
obesity if possible,
- balanced diet including
- 9 portions of vegetables
or fruit a day (9 for men, 7 for women),
- minimal
of animal or 'hard' vegetable fats,
- low
salt, see the evidence
Alcohol should
be limited to one drink or unit a day, six days a week
(Mukamal 2004). More than this leads to brain damage.
- Oily
fish such as sardine, salmon,
tuna, trout, at least twice a week (small amounts are
fine...not a whole salmon!).
- Fibre
and healthy fats in the diet slows down retinopathy. No transfats
and minimal saturated fat.
|
blood pressure |
- 130/80 (see
graph) or preferably less
- (120/75 ..home monitoring)
- 125/75 or less if protein in urine present (115/70..
home monitor)
- ACE inhibitors
or Angiotensin Receptor Antagonists unless young/pregnant/very
low blood pressure/poorly tolerated
- 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.
- LDL <2
|
smoking |
- smoking 20
a day triples/quadruples retinopathy
- passive smoking may double
retinopathy: room-mates inhale at least 25%
|
insulin |
|
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?
|
glucose level |
- 5.0-7.2 mmol/l before meals
- <10.0 mmol/l after meals
- no serious hypos
|
Glitazones |
- 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 |
neuropathy |
page |
issues |
many patients receive totally inadequate care BMJ 11. Some call this 'institutionalised neglect'. |
