Diabetic Eye Disease Monitoring and Treatment
What is diabetic eye disease?
Diabetic eye disease refers to a spectrum of eye conditions that can affect people with diabetes. The main problem is located in the vessels of the eye as a chronic high blood sugar level damages the blood vessel walls and lead to leakage of fluid into the retina layer of the eye. When the central area of the retina or macula is affected, this is known as diabetic macular edema (DME). At the same time, the retinal tissue is slowly deprived of adequate oxygenation. In severe cases, the chronic deficiency of oxygen results in the reactive development of abnormal blood vessels (proliferative diabetic retinopathy or PDR) which are more prone to bleed. This can result in bleeding within the inner vitreous cavity of the eye (vitreous haemorrhage or VH), leading to sudden loss of vision.
Adults with diabetes are at higher risk of developing cataracts than those without. This can also occur at an earlier age. Those with diabetes should also be screened for glaucoma as the risk of glaucoma is almost double that of those without diabetes.
On a more positive note, patients with diabetes who also have hypertension and/or high cholesterol could reduce their risk of vision loss with optimal control of these other vascular risk factors.
How often should screening for diabetic eye disease be performed?
Diabetic eye disease tends to be diagnosed only years after the initial diagnosis of diabetes, especially if the diabetic control is good. However, as some patients are diagnosed late or are unable to maintain good control, it is a good idea to start screening once a year from the time of diagnosis of diabetes. Should early signs be detected, your eye doctor will likely recommend more frequent follow-up and potentially recommend treatment where appropriate.
What treatments are available for diabetic eye disease?
Diabetic macular edema (DME):
- Anti-VEGF Injection Therapy
Anti-VEGF drugs are injected into the vitreous cavity to block a protein called vascular endothelial growth factor (VEGF) which stimulates abnormal blood vessels to grow and leak fluid.
- Focal/grid macular laser treatment
Small laser burns are made to slow the leakage of fluid and reducing swelling in the retina. The procedure is usually completed in one session, but some people may need more than one treatment.
Corticosteroids, either injected or implanted into the eye, may be used alone or in combination with other treatments. However, corticosteroid use in the eye can increase the risk of cataract and glaucoma.
Proliferative diabetic retinopathy (PDR):
Panretinal laser photocoagulation (PRP)
One to two thousand tiny laser burns are made in areas of the retina away from the macula. These laser burns are intended to cause abnormal blood vessels to shrink. Like focal laser, although treatment can be completed in one session, two or more sessions are sometimes required.
Vitreous haemorrhage (VH):
Vitrectomy is the surgical removal of the vitreous gel in the center of the eye. It clears away the blood-stained vitreous gel and has the potential to help restore some vision in those with acute visual loss.
What if treatment does not improve vision?
Unfortunately, although the above treatments have the potential to preserve vision for as long as possible, some patients may experience visual loss over time as the condition fails to respond to treatment. This is more likely to occur in more severe cases with poor diabetic control, particularly in the presence of other risk factors.
Low vision services are available to recommend devices that may help make the most of remaining vision. Your eye doctor will be able to help you make an appropriate referral.