What is Retina?
Retina is the layer in the back of the eye where the images are formed. It is the light-sensitive layer of tissue that lines the inside of the eye and sends visual messages through the optic nerve to the brain. Retina acts like a screen in a cinema theater. Anything that causes changes in Retina can lead to demission of vision.
Diseases of the retina can lead to partial or total loss of vision. For young people, retinal disease can be caused by the presence of other diseases such as diabetes. For older people, the most common retinal diseases are associated with conditions such as macular degeneration.
Dimnision of Vision
Sudden loss of Vision
Distortion of Shapes
Patches of Blurred Vision
Instances of Transient Loss of Vision
Any other symptom in the eye which was not there earlier
People with Diabetes, Hypertension, Myopia, Family history of some retinal diseases should get their retina examined every 6 months even in the absence of any symptoms. Sometimes your doctor might ask you to get your retina examined especially if you have been prescribed some drugs.
Comprehensive Eye Examination
Your eye care professional will conduct a complete and comprehensive eye examination. This usually includes –
Visual field test. This test measures your peripheral (side vision). It helps your eye care professional tell if you have lost peripheral vision, a sign of glaucoma.
Dilated eye exam. In this exam, drops are placed in your eyes to widen, or dilate, the pupils. Your eye care professional uses a special magnifying lens to examine your retina and optic nerve for signs of damage and other eye problems. After the exam, your close-up vision may remain blurred for several hours. This is the most important part of your eye examination for checking the retinal diseases.
Tonometry is the measurement of pressure inside the eye by using an instrument called a tonometer. Numbing drops may be applied to your eye for this test. A tonometer measures pressure inside the eye to detect glaucoma.
Investigations like FFA, OCT, B-Scan Ultrasonography might be done to confirm the diagnosis and to plan your further treatment.
Some of the diseases :
In young people, the major cause of vision loss due to retinal disease is diabetic retinopathy. Diabetes can cause progressive damage to the eye’s retina. In the early stages of diabetic retinopathy, there are usually no symptoms. The good news is that about 90 percent of blindness due to diabetic retinopathy is preventable if it’s diagnosed early.
An extensive eye examination should be done as soon as diabetes is diagnosed, and at least every year after that. If diabetic retinopathy is diagnosed, eye examinations may need to be done more frequently. Timely, specialized laser treatment of the eye - specifically for diabetic retinopathy - is beneficial for people with this condition. Intravitreal injections of drugs are also used for the treatment along with laser photocoagulation. Advanced cases may have to undergo surgery.
In older people, the retinal disease that most often causes vision loss is macular degeneration. Macular degeneration affects the central vision used for reading and fine visual tasks. Symptoms include distorted vision, where straight objects appear bent. Other symptoms include blind spots or dark patches in the central vision.
Changes in vision in one eye may go unnoticed if the other eye has good vision, therefore it is important for people with macular degeneration to have their eyes tested separately to detect these changes. There are new, highly effective treatments for neovascular (wet) macular degeneration. Early detection and treatment is essential to prevent permanent damage to vision.
Retinal detachment is an uncommon but significant cause of visual loss. Retinal detachment can often be prevented by treating retinal tears before they lead to detachment. Warning symptoms include the sudden onset of spots or lines that appear to ‘float’ in the vision and may look like insects. Other symptoms include flashes of light, which can appear as ‘lightning streaks’ to the side of the vision. If this occurs, seek an eye examination immediately. Laser treatment of retinal tears can often prevent further complications. If the retina is detached already then surgery is the only option.
Other conditions such as retinal vascular disease may affect the macula and cause loss of vision. A retinal examination by an ophthalmologist can determine the exact nature of the retinal condition.
There are a large number of retinal diseases which may present with very few symptoms initially. If you see any unusually visual symptom, you should immediately get it checked. Timely diagnosis and treatment can be very helpful.