Diabetic Eye Disease: Retinopathy and Maculopathy
What is Diabetic Eye Disease?
Diabetic Eye Disease refers to a group of eye problems that people with Diabetes Mellitus may face as a complication of the disease. People with diabetes have an increased risk of eye problems, including Diabetic Retinopathy, Macular Oedema and Cataracts. If left untreated, all can lead to severe vision loss or even blindness.
What is the retina and how does it function?
The retina is a thin layer of tissue that lines the inside of the back of the eye. The retina is supplied with oxygen and nourishment by blood vessels. Light enters through the front of the eye (cornea, pupil and lens) and focuses on the retina. Simply speaking, the retina can be divided into two main areas: the macula, which is responsible for our sharp and detailed central vision, and the mid and peripheral retina, which are responsible for our peripheral (side) vision and helps to detect movement. The retina converts this light into electrical signals that eventually travel to the brain.
What is Diabetic Retinopathy?
The delicate network of blood vessels which supply the retina with all the nutrients required to work successfully can become damaged as a result of Diabetes. Most commonly, this leads to a lack of oxygen reaching the retina and the growth of abnormal vessels which can bleed or develop into scar tissue. In turn, this can lead to intraocular bleeding or retinal detachment with loss of vision or even blindness. Symptoms are not always noticeable and can develop gradually affecting the vision. If the Diabetic Retinopathy is too advanced, there is a chance it may not be able to be successfully treated, hence the need for regular examinations.
Who can get Diabetic Retinopathy?
All patients with Diabetes are at risk of developing Diabetic Retinopathy. The longer you are diabetic, the greater the risk. Other factors which can affect this include blood sugar control and high blood pressure.
Can Diabetic Retinopathy be treated?
Most patients only need to be monitored through regular dilated examinations. These exams usually include non-invasive Retinal Imaging such as Optical Coherence Tomography (OCT) scans and Ultra-Wide Field photography.
Laser treatment, intraocular injections or surgery, as single or combination treatment, can usually stabilise the condition, preventing blindness and, in some patients, even improve vision.
Prof Stanga has pioneered new diagnostic and treatment technologies and techniques, such as OCT, anti-VEGF and steroid injections and Pascal® laser. If needed, this will be discussed with you.
What does Diabetic Retinopathy look like?
Non-Proliferative Diabetic Retinopathy
Non-Proliferative Retinopathy is the term used to describe the earlier stages of Diabetic Retinopathy. Small changes develop in the blood vessels that look like tiny red dots; these are called microaneurysms. There may also be larger red blotches which are the result of haemorrhages that lie within the retina.
Non-Proliferative Retinopathy usually does not affect your sight and may not need treatment. However, it is essential that the condition is monitored and that your Diabetes is controlled as well as possible by your GP or Diabetic Specialist. The appropriate interval for visits to monitor the condition will be determined by Prof. Stanga. As time goes on, the blood vessels may become constricted and the retina starved of oxygen and nutrition. This progression can lead to proliferative retinopathy and blindness if left untreated.
Proliferative Diabetic Retinopathy
This stage follows on from Non-Proliferative Retinopathy; you may develop abnormal and new and fragile blood vessels.
By themselves, these new vessels may not cause symptoms or loss of vision. However, at this stage, your sight is already at risk as the new vessels may bleed or may develop scar tissue that can pull the retina away from the underlying layers of the eye. These complications may require surgery to stabilise or improve vision and prevent blindness
If Diabetic Maculopathy is present, your central vision becomes affected. Reading the small print, distinguishing fine detail or faces and differentiating colours can become difficult. This is normally caused by the small blood vessels leaking fluid, fats and proteins into the macula. The swelling secondary to this leakage is called Oedema. Intraocular injections of medications and/or laser treatment may be used to prevent further loss of vision and in some patients even improve it.
If the blood vessels in the macula become too constricted, oxygen cannot flow to the retina and the tissue will “starve”. This causes the cells that capture light to die and your sight to deteriorate. The term for this condition is “Ischaemic Maculopathy”. There is no treatment for Ischaemic Maculopathy at the current time. Prevention, by maintaining the best possible control of your Diabetes and other different blood parameters such as blood pressure are again essential.
How will I know if I have Diabetic Retinopathy or Maculopathy?
Diabetic Retinopathy and Maculopathy may present on their own or in combination.
Initially, neither may cause visual symptoms. Even stages that require treatment may not cause visual symptoms in some patients. Diabetic Retinopathy and Maculopathy are detected by examining the back of your eyes through fully dilated pupils and looking at your retina. Non-invasive retinal imaging using OCT scans may be necessary. You should have annual dilated eye exams during your lifetime to screen for any early changes.
Innovative technology such as Ultra-Wide Field photography which allows the visualisation of a significantly larger area of the retina compared to standard photography, as well as Swept-Source Optical Coherence Tomography (SS-OCT) and Angiography (SS-OCT) may allow for an earlier diagnosis.
Why is treating Diabetic Retinopathy and Maculopathy important?
Diabetic Retinopathy and Maculopathy are serious eye conditions that can lead to reduced vision or even blindness. Proper management of your Diabetes with early diagnosis and treatment for sight-threatening retinopathy and maculopathy reduces the risk of loss of vision or blindness. If changes occur, ocular treatment needs to be administered at the appropriate stage to reduce the chance of permanent vision loss. As you may not be aware of these changes, particularly in the earlier stages, it is very important that you keep your scheduled clinic appointments.
What are the common symptoms of Diabetic Retinopathy and Maculopathy?
Blurred or distorted central vision, sudden onset of floaters or loss of visual field in diabetic patients must be assessed at the earliest opportunity.
However, it is important to remember that as some patients may not experience visual symptoms, regular examinations are essential.
Treatment for Diabetic Retinopathy and Maculopathy
If you develop Proliferative Diabetic Retinopathy (the growth of abnormal and new blood vessels) or Maculopathy, you will be advised to undergo tests and treatment. The aim of treatment in Proliferative Diabetic Retinopathy is to stop the retina from forming new abnormal blood vessels. If the treatment is successful, the new vessels will shrink and some of them even disappear over a few months. The aim of treatment in Diabetic Maculopathy is to reduce the swelling or Oedema.
Treatment is tailored to the stage of disease and patient and can include one or more of the following: anti-VEGF or steroid injections, Pascal® laser or surgery.
Laser treatment can be applied either to a localised area or the entire retina with the exception of the macula, or both.
If you have developed a vitreous haemorrhage (bleeding) or scar tissue causing a retinal detachment, it may be necessary for you to undergo vitrectomy surgery.
If you have developed a cataract, then surgery is needed to remove the lens in your eye which is replaced with a clear artificial lens implant (intraocular lens).
If you develop high eye pressure or glaucoma, then drops may be given to help control the pressure and decrease the change for any long term damage.
Things to remember:
Diabetic Retinopathy and Maculopathy can worsen over time. However, the following measures can help you to reduce the risks of developing any sight-threatening changes:
- Work with your GP or ideally a Diabetes Specialist (Endocrinologist) to control your blood glucose as effectively as possible
- See your doctor regularly to check that your blood pressure and cholesterol levels are normal
- Ensure you have regular Ophthalmic Screening appointments, including OCT scans and Ultra-Wide Field photography of your retina.
See a Vitreo-Retinal Eye Surgeon at the earliest if you develop any change in vision, especially: blurred or distorted central vision, sudden onset of floaters or, loss of visual field.