Sight threatening eye disease is a serious complication of diabetes and can often be present without visual symptoms. Early detection and appropriate management can greatly reduce risk of visual loss.
All T2DM patients must have a baseline visual examination at the time of diagnosis and yearly thereafter. The presence of retinal changes would merit more frequent examination schedules.
Similarly, in women with known T2DM who are planning pregnancy should have a preconception check and then during the first trimester. Women found to have diabetes during pregnancy (GDM) should also have a visual examination as soon as the diagnosis is made. The schedule thereafter would depend on the physician discretion dependent on the findings at the baseline examination.
This examination should be carried out by a person skilled in diagnosing diabetic eye involvement.
Patients at special risk, and those who show the presence of abnormalities, may require more frequent checkups; these patients should be seen along with a specialist.
Macular edema, characterized by retinal thickening from leaky blood vessels, can develop at all stages of retinopathy.
For a more detailed chart showing the morphological and functional changes at various stages of diabetic retinopathy, see Appendix 12 a.
There are usually no symptoms in the early stages of diabetic retinopathy. Vision may not change until the disease becomes severe. This is why regular examinations for people with diabetes are so important. But it may not be feasible to carry out a retinal examination at every visit. Thus, one should tell the patient to look out for signs and symptoms which may herald a serious problem and they should be told that they should seek medical attention urgently.
Macular involvement in diabetic retinopathy is an emergency, and unless diagnosed in the very early stages and managed adequately, it can lead to significant visual loss (central vision loss).
It is recommended that all patients use an Amslers Recording Chart which allows early detection of maculopathy.
The Amsler's chart is very useful for early detection of macular problems and thus is very important as this may be an early sign of macular problems and lead to a loss of central vision.
It will NOT detect proliferative diabetic retinopathy, most preproliferative changes and other types of damage that may threaten vision, nor is it useful for detecting any of the early changes.
A normal Amsler grid test does not rule out the presence of retinopathy that can threaten vision and thus, cannot replace regular fundus examinations
|Lifestyle||30-60 minutes exercise a day, moderate alcohol consumption only, avoid obesity if possible, balanced diet including 5 portions of vegetables or fruit a day, with the minimal of animal or 'hard' vegetable fats, and very low salt.|
|Blood pressure||130/80 or less 125/75 or less if protein in urine present|
|HbA1c||6.5% or less with very few or preferably no hypos. If hypos develop, see expert advice. ACE inhibitors or AT11 unless young/pregnant/very low blood pressure/poorly tolerated.|
|Cholesterol||<4.66mmol/l, and statins recommended for most adult patients|
|Smoking||Smoking 20 a day triples retinopathy (passive smoking: room-mates inhale at least 25%)|
There are no known specific drugs which have been proven to be of help in reducing the progression of retionopathy, although some recent studies have shown that RAAS blocade may help in retarding the progression of diabetic retinopathy.
Laser photocoagulation therapy is effective in reducing the risk of further visual loss and is generally useful in preventing blindness in diabetics with high risk proliferative retinopathy and macular oedema. There is some evidence that early treatment with laser photocoagulation, without waiting for the development of severe changes, may lead to a better prognosis in preventing vision loss.
Vitrectomy may is the mode of treatment in patients with traction retinal detachment or vitreous hemorrhage.