OCT IMAGE OF MACULA
Age related macular degeneration (AMD)
AMD is one of the common causes of reduced vision among older people. AMD damages the macula resulting in central distortion, central field defect and reduced vision. The progression of vision loss depends on the type of AMD. There are two main types of AMD, dry and wet. Wet AMD results in rapid reduction in vision and this is due to formation of abnormal blood vessels. The progression of dry AMD is generally very slow. AMD does not lead to complete blindness but the loss of central vision results in difficulty in reading, driving, and writing. The treatment and diagnosis is done by an Ophthalmologist. Your eye surgeon will examine your eyes and perform some scans of your macula. The treatment for dry AMD is generally preventive and requires life style changes. Wet AMD treatment requires injections of drugs in to the eye. The visual outcomes are much better if the treatment is started early.
Diabetes mellitus can affect your eyes by causing cataract, optic neuropathy and diabetic retinopathy. Diabetic retinopathy can affect the retina by either causing swelling at the macula (macular oedema) or abnormal vessels on the retinal surface. These abnormal vessels can break down causing vitreous haemorrhage (bleeding at the back of the eye). Untreated diabetic retinopathy can lead to permanent blindness. If you have been diagnosed with diabetes mellitus than you should enrol in the diabetic retinopathy screening programme. If you develop any complication of diabetic retinopathy than you should see an Ophthalmologist. Your eye surgeon will examine your eyes and arrange for macular scans or retinal angiograms, if necessary. Diabetic retinopathy is treated, when indicated by means of retinal laser, injections of drugs in to your eyes, or a combination of the two. It is important to control your blood sugar, blood pressure, stop smoking and exercise regularly.
Retinal vein occlusion
Retinal vein occlusion or blockage can result in leakage of fluid and blood in to the retina/macula resulting swelling at the macula or reduced oxygen supply to the retina. This can cause reduced vision or long term complications like large bleeds at the back of the eye (vitreous haemorrhage) due to abnormal blood vessel on the retina. The blockage in the retinal blood vessel can occur either in the main retinal vein (central retinal vein occlusion) or a smaller branch (branch retinal vein occlusion). You will need to be assessed and reviewed regularly by an Ophthalmologist. He will examine your eyes and may order tests such as a scan of your macula, angiogram of your retina and some blood tests to rule out any underlying causes for the blocked blood vessels. Predisposing factors for vein occlusion include high blood pressure, diabetes mellitus, smoking and some blood disorders. The treatment may include laser treatment to the retina and injections of drug in to your eye.
Intravitreal injections are injections of drugs in to the vitreous, a jelly like substance in the back compartment of the eye. The drugs commonly used are anti VEGF and steroids. They anti VEGF drugs such as lucentis and eylea, are used in patients with wet form of AMD, myopic choroidal neovascularisation, diabetic retinopathy and retinal vein occlusion. Intravitreal steroids are used mainly in patients with oedema secondary to diabetes mellitus and retinal vein occlusion.
This procedure takes about 10 minutes although the injection itself is completed in a few seconds. In many cases these injections need to be repeated at monthly intervals. Your Ophthalmologist will tell you about the number and frequency of these injections, based on your eye condition. These injections are very low risk and these will be discussed by your Ophthalmologist prior to the procedure.