Refractive disorder is a commonly found structural disorder of the eye that makes it difficult for the eyes to sharply focus the light rays on the retina, thus resulting in a blurry vision. There are 3 types of refractive disorders.
Nearsightedness: In nearsightedness, closeby objects can be seen clearly but, those beyond a particular distance appear blurry. It is caused either by a change in the cornea or the lens or by a natural change in the shape of the eyeball.
Farsightedness: In farsightedness, objects at a distance appear clear whereas closeby objects appear blurry. Farsightedness is caused when your eye is too short lengthwise causing an image to focus behind the retina instead of directly on it.
Astigmatism: In astigmatism, objects at any distance appear blurry and wavy. The eye of a person with astigmatism is shaped like the back of a spoon. Hence, when light enters the eye, it is not refracted equally, allowing only a part of the object to be in focus.
Read more on refractive disorders in Treatments & Surgeries sections.
Diabetes can affect the eyes and vision in a number of ways. It may
lead to:
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Frequent fluctuations in vision
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Cataract at a young age
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Decreased vision due to involvement of optic nerve
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Temporary paralysis of the muscles controlling the movement of eyes, thus leading to double vision
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Increased chances of contracting glaucoma
Beyond these ailments, the most significant complication of diabetes in the eye is diabetic retinopathy.
What is diabetic retinopathy?
Diabetes affects the small vessels of the retina in the eye. There are various stages of diabetic retinopathy:
Non-proliferative or background diabetic retinopathy: This is an early form of diabetic retinopathy and may not lead to any decrease in vision, but can lead to other more serious forms of retinopathy that affect
the vision.
Diabetic maculopathy: Vision is usually not affected until macula, a part of the eye is involved. Macula if involved, the patient experiences gradual, progressive reduction in vision, for both distant and
near objects.
Proliferative diabetic retinopathy: This is an advanced stage of diabetic retinopathy, where the blood supply of the retina reduces substantially. In response to this, new fragile blood vessels grow on the surface of the retina. These new vessels are very fragile and bleed easily. These may lead to serious vision problems like vision loss and blurred vision.
The longer a person has had diabetes, greater are his/her chances of contracting diabetic retinopathy. Almost 80% of people who have had diabetes for 15 years or more, suffer from retinal problems.
Can diabetic retinopathy spur other eye disorders as well?
The process also causes scar tissues to develop, which can pull the retina away from the back of the eye. This is known as retinal detachment, and can lead to blindness if untreated.
In addition, abnormal blood vessels can grow on the iris (the coloured part in the front of your eye) which can lead to glaucoma.
Can something be done to prevent diabetic retinopathy?
There is no treatment as such to prevent diabetic retinopathy altogether. Besides a good control of blood sugar, one must exercise regularly, keep blood pressure under control, avoid smoking and avoid obesity.
How do I know if I have diabetic retinopathy?
You might not know that you are having diabetic retinopathy, as there are no symptoms in the earlier stages of the disease. Therefore it is essential to have periodic evaluation of your eye by an ophthalmologist to detect the condition early. Early diagnosis and timely treatment is very essential in preventing the complications of this disease and thus maintaining clear vision.
If I have diabetes, how frequently should I get my eye examined?
If you have diabetes, you should get a yearly examination with your ophthalmologist. Once you are diagnosed with diabetic retinopathy, the frequency of visits will vary in accordance with the severity of
the disease.
What are the common tests done for diabetic retinopathy?
First your vision is tested with the alphabet chart.
The back of your eye is then examined after dilating your pupils, using an instrument called ophthalmoscope.
Sometimes your ophthalmologist may advise a special test called fluorescein angiography, which is a test in which a series of photographs of the retina are taken with the help of a special camera. These photographs are taken after giving the patient an injection of a yellow dye. This dye reaches the retina through the blood stream and helps in seeing the blood vessels of retina more clearly. This test helps the doctor to determine further course of treatment.
Dry Eye Syndrome is a disease where the eye loses the ability of keeping itself sufficiently lubricated either due to decreased tear production or increased tear film evaporation.
How do I know if I have dry eyes?
Frequent irritation, burning sensation, itching, foggy vision, sensing the presence of some foreign particle in the eye, eye pain and fatigue are some of the common symptoms of dry eye syndrome.
What are the causes of dry eye syndrome?
Aging, hormonal changes, autoimmune diseases and some medications can result in poor production of tears. People who sit in front of the PC for long hours are also susceptible to dry eye syndrome.
Evaporative loss of the watery tear layer is usually a result of an insufficient overlying lipid layer.
Your cornea specialist would conduct a battery of dry eye tests to determine the cause of your dry eye. In some cases, a blood checkup for autoimmune diseases may also be suggested.
What if dry eye is not treated in time?
Dry eye syndrome if not diagnosed and treated in time, can lead to patient resorting to remedies like rose water, netraprabha, honey and so on. Using such products can be counterproductive.
Prolonged dry eye can reduce work efficiency. Severe dry eye can also lead to corneal infections and perforations.
To know further on the treatment options available for dry eye syndrome, refer to the Treatments section.
Glaucoma is an eye disease caused due to increased pressure within the eyeball. It is also known as a “sneak robber of sight”, because if it is left unattended to, the pressure damages the optic nerve, leading to progressive, irreversible loss of vision.
Which are the two types of glaucoma?
Closed angle glaucoma: It often appears suddenly and is painful. Visual loss can progress quickly but the discomfort often leads patients to seek medical attention.
Open angle or chronic glaucoma: It tends to progress at a slower rate and the patient may not notice that they have lost vision until the disease has progressed significantly.
Once you have been diagnosed with glaucoma, the goal is to stop the progression of vision loss. For details on the treatments for glaucoma refer to the Treatments section.
Retinal detachment is a disorder in which the retina separates from its underlying layer of support tissue. The retina is a thin layer of light-sensitive tissue that translates images into neural impulses for the brain to interpret. Initial separation may be localised, but if left untreated, the entire retina may detach, leading to vision loss and blindness.
What are the causes of retinal detachment?
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Weak spots in the retina (lattice degeneration)
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Injury
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Long-term diabetes mellitus
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Myopia
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Retinal hole or tear
Sometimes retinal detachment occurs without any specific reasons.
To know more about the treatment options available for retinal detachment, refer to the Surgeries section.
These focus on abnormalities of the structures around the eye caused either due to injury to the eye muscle, congenital defects, nerve disorders or aging.
What are the kinds of eyelid and orbital disorders?
Ptosis: Ptosis is a condition whereby the natural position of the upper eyelid is droopy or sagging and limits a person's field of vision.
Entropion: Entropion is a medical term used to describe the sagging and inward turning of the lower eyelid and eyelashes.
Ectropion: Ectropion is a condition used to describe sagging and outward turning of the lower eyelid and eyelashes.
For more information on the treatments for the above, refer to the Treatments section.
Which are the known vision disorders in children that we address?
Squint is a known disorder in children that we address.
What is squint and what are its causes?
Squint is a condition in which the eyes do not look in the same direction. The movement of each eye is controlled by 6 muscles that pull the eye in various directions. A squint develops when the eye muscles do not work in a balanced way and the eyes do not move together correctly. Most squints are contracted in the first 3 years of your life.
What are the symptoms of squint?
Eyes do not look straight ahead. It is quite normal in newborn babies because their eyes look cross occasionally, particularly if they are tired. When it is noticed in children beyond three months of age, it is advisable to go to an eye specialist.
When a child looks at a person with one eye closed, or with its head turned to one side, it may point to the fact that they are experiencing double vision and could be an indication that they have a squint in the eye.
Keratoconus is a slow and progressive weakening of the corneal tissue that leads to thinning of the cornea and its gradual outward bulging.
How do I know if I have Keratoconus?
Blurry and distorted vision, observing of multiple images, poor night vision and increased sensitivity to light are some of the common warning signs of Keratoconus. In its advanced stage, the disease can impair a patient’s ability to drive a car or read a print.
What are the causes of Keratoconus?
While the reasons for contracting it have not been deduced objectively, it is estimated Keratoconus can be caused due to genetic reasons, environmental factors and cellular
abnormalities.
What is the treatment of Keratoconus?
A patient of keratoconus usually needs help in the form of spectacles (early cases), semisoft contact lenses (special forms like Rose K, scleral and piggy back lenses). In advanced cases however one needs corneal transplantation (DALK/PK). However in mild to moderate cases one can stabilize the condition with a procedure called Collagen Cross Linking.
Read more about Collagen Cross Linking in the Surgeries section.