Dr.Maneesh Bapaye
Dr.Bapaye Hospital
Nashik
Diabetes mellitus is a lifestyle disease that is rapidly increasing all over the world. Unfortunately, the incidence of diabetes mellitus in India is among the highest in the world. Diabetes causes damage to all the organs in the body. Eye also gets affected in diabetic patients.
Patients with diabetes get some of the following changes in the eyes
- Frequent change in spectacle power,
- Repeated Stye formation on eyelids
- More prone to glaucoma
- Cataract formation
- Diabetic retinopathy causes most serious damage to the eye
Let us understand about diabetic eye disease
To begin with, let us understand structure of the eye
The eye works like a camera. Cornea and the lens of the eye focus the rays of light coming from outer objects. The retina is the film of this camera. Image of the object created by the retina. The center of the retina is the most sensitive spot of vision known as the macula. It is responsible for finarities of vision like reading, recognizing details, facial identification etc. Diseases of the macula cause severe damage to the vision. The light rays entering the eye are focused by the cornea and the lens onto the retina.The image formed on the retina is transmitted to the brain through the optic nerve. In the brain, in the visual cortex, the image is analysed.
Lets us understand more about diabetic retinopathy
Diabetic retinopathy results from damage to the blood vessels of the retina. Over time, too much sugar in the blood can lead to the blockage of the tiny blood vessels that nourish the retina, cutting off its blood supply. As a result, the eye attempts to grow new blood vessels. These new blood vessels do not develop properly and can leak easily.
Diabetic retinopathy does not lead to sudden loss of vision. It progresses gradually over a period of time. There are stages of severity of diabetic retinopathy. These are as follows
Non-proliferative DR (NPDR): In early stages, patient’s have no symptoms. There is minimal or no vision loss. Leaking blood spots and cholesterol deposits can be seen on retinal examination.
Proliferative DR (PDR): In this advanced stage, new blood vessels grow on the surface of the retina. If not treated in time, they can burst and lead to hemorrhage in vitreous cavity leading to sudden vision loss.
Diabetic Macular Edema (DME): Diabetic retinopathy leads to swelling of the central spot of the retina, known as macular edema. Macular edema results from leakage of fluid and cholesterol crystals from leaky blood vessels at the macula. It leads to severe damage to fine vision required for reading, writing etc.
Risk factors for diabetic retinopathy include,
- Duration of diabetes: Longer the duration of diabetes, higher the chances that patient will develop diabetic retinopathy
- Poor blood sugar control: If the blood sugar is not under good control, diabetic retinopathy develops earlier in the disease and tends to be more severe
- High blood pressure
- High cholesterol
- Obesity
Early detection and treatment can significantly improve outcomes. Regular eye exams are crucial for people with diabetes!
Symptoms of diabetic retinopathy
In early stages the majority of patients do not have any symptoms. Patients develop symptoms when disease is significantly advanced. They may iclide
- Floaters, spots or dark strings in your vision
- Blurred vision
- Fluctuating clarity of vision
- Dark or empty areas in your vision
- Dark, floating spots or streaks that look like cobwebs, which are caused by bleeding blood vessels in the retina
- Blurry vision, caused by diabetic macular edema (DME) or DME
- Neovascular Glaucoma, which is the result of development of abnormal blood vessels on the surface of the iris and angles of the eye. This can lead to extremely painful blind eye
- Retinal detachment
It is important to note that not everyone has symptoms in the early stages of diabetic retinopathy, and some only experience mild vision problems. However, as the condition progresses, vision loss can occur, and so it is important for diabetics to get a comprehensive dilated eye exam at least once a year.
If a patient is diagnosed with significant diabetic retinopathy. He may be subjected to following investigations
- Retinal Photography/ Fundus photography: This test is done to document the status of the retina when the patient does not have significant diabetic retinopathy.
- Fluorescein angiography: Fluorescein dye is injected in the vein of the arm and as the dye reaches retinal circulation, retinal photos are taken with a specialized camera known as fundus camera. It gives a detailed picture of the presence of abnormalities in blood vessels, areas where blood vessels are absent and where new, abnormal blood vessels are grown.
(You can watch the video of fluorescein angiography on following link)
- Optical Coherence Tomography (OCT): This non-invasive test is done to diagnose presence and ascertain severity of macular edema. It is also helpful to follow up the patients after the treatment if macular edema is reducing or not and whether the treatment can be continued or needs to be changed
(You can watch the video of OCT on following link)
Optical Coherence Tomography (OCT)
- OCT Angiography: This is the latest test which is used to evaluate blood vessels using OCT technology. No injection is required for this test. It can be done easily in a few minutes and gives important information about blood vessels of retina
- Ultrasonography of the eye: This test is performed when a patient develops bleeding inside the eye and retina can not be visualized. This is used to see the position of the retina. It is helpful in planning the surgery.
Color Fundus Photo Fluorescein Angiography OCT Angiography
Treatment of diabetic retinopathy:
- Controlling blood sugar and blood pressure is the first step to stop vision loss.
- Retinal Laser Treatment: Retinal laser treatment is done on OPD basis. It helps to shrink abnormal blood vessels on the retinal surface. Laser treatment is also useful to reduce diabetic macular edema. Each laser sitting may take between 10 to 15 minutes. Number of sittings a particular patient requires depends upon severity of disease. Retinal specialist treating the patients can guide the each case based on its merits.
(Watch video of retinal laser on following link)
- Intravitreal Injections: AntiVEGF injections like Avastin, Razumab, Accentrix, Pagenax or Eylea are given inside vitreous cavity. The procedure is performed in the operation room to maintain sterility. It is used to reduce macular edema, shrink abnormal blood vessels, to reduce bleeding inside vitreous cavity or 4 days prior to retinal surgery to improve surgical outcomes.
- Steroid injection known as Kenacort or a steroid implant known as Ozurdex may also be given in cases of severe macular edema,
(Watch video of intravitreal injection on following link)
Intravitreal Anti-VEGF Injections
Read more about injections by scanning following QR Code
- Surgical management: Surgery known as vitrectomy is performed when patients develop vitreous hemorrhage that is not responding to other treatments or if the patient develops retinal detachment.
(Watch video of surgery on following link)
Vitrectomy for Proliferative Diabetic Retinopathy
A diabetic patient must undergo periodic detailed eye examination including retinal examination even if they do not have any symptoms. Here are the recommended intervals for patients with diabetes to undergo retinal examination for diabetic retinopathy ¹:
- Type 1 diabetes: first retinal examination 3 to 5 years after diagnosis, re-examination every 1 to 2 years
- Type 2 diabetes: first retinal examination at the time of diagnosis, re-examination every 1 years
- Pregnant patients with type 1 or type 2 diabetes: first retinal examination soon after conception and early in the first trimester, re-examination every 1 to 2 years
- Once patient has developed severe disease that requires treatment, patient must undergo retinal examination every 3 months, after conclusion of treatment, for rest of their lives
Written by:
Dr. Maneesh Bapaye
Cataract and Retinal Specialist
Dr. Bapaye Hospital,
Behind NDCC Bank, Old Agra Road, Nashik
Phone: (0253) 2506505/2509421
email: drbapayehospital@rediffmail.com
Website: bapayeeyehospital.com
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