Dr Vinokali Achumi
A general layman perception about eye testing is that it is only for checking the power of the glasses we need. However, there is much more to a full eye examination than visual acuity tests (refractive error testing of the eye).
Most of our patients are unaware about the importance of a full eye examination and tend to get spectacles from optical shops and buy over the counter eye drops for most eye problems, not realizing that getting spectacles alone isn't enough or putting a wrong eye drops can cause more harm to their eyes. Therefore, this article is an attempt to spread awareness on five important eye diseases out of many affecting the eyes.
1. Quarantine Myopia (near sightedness)
What is it?
During the lockdown period due to COVID-19 pandemic, getting work done involved computers, laptops, and mobile phones or tablets, which increases the screen time. This visual stress could be a cause for an accelerating effect on myopia progression especially in young children. Studies also supports that young children are more sensitive to myopic triggers from the environment.
In addition, due to inability to visit eye doctor during lockdown, some of them continued to use spectacles with inadequate power which again put a strain on eyes. This further increased their refractive error (eye sight power).
Why is this a big concern?
If the Refractive error (near-sightedness) is left untreated it would result in symptoms such as
a) Eye strain
b) Headaches
c) Blurred vision
d) Intermittent double vision, etc.
The consequence can have a lasting effect on the child’s performance at school. Moreover, children who become near-sighted very early in life which has a tendency to experience a worsening and progression of near-sightedness that continues throughout childhood — and this puts them at a greater risk of very serious and potentially sight-threatening eye conditions later in life, such as glaucoma, cataract and retinal detachment.
Awareness about the Refractive error, its associated symptoms and taking your children for proper eye check-up is essential in prevention of blindness caused by Refractive error.
2. Diabetic Retinopathy
What is it?
In simple words, it is a complication of diabetes that affects the eyes. It is caused by damage to the blood vessels in the tissue at the back of the eye (retina). The condition can develop in those who have type 1 or type 2 diabetes for many years.
How does one get it?
a) Poorly controlled blood sugar
b) Long duration of diabetes mellitus
What are the symptoms?
a) Spots or dark strings floating in your vision (floaters)
b) Blurred vision
c) Fluctuating vision
d) Dark or empty areas in your vision
e) Vision loss
Many of us are unaware that uncontrolled diabetes mellitus can lead to blindness.
Similar to how it causes kidney disease, heart disease and neurological problems, it can also affect your eyes, depending on the duration and how well your diabetes is controlled with medication.
Not long ago, a patient in her forties came with a complaint of with blurred vision to my OPD. She had uncontrolled diabetes mellitus for more than 10 years. When I examined her eyes, I found that she had developed an advance form of Diabetic retinopathy. In such case, when the Diabetic retinopathy has reached its last stage, even surgery to salvage the vision doesn't do much benefit.
Therefore, I request all patients who have diabetes mellitus to get your eye checked regularly by an eye specialist and avail the treatment, if needed, at the earliest to prevent blindness.
What are treatment options?
Treatment will depend on how severe it is.
1) Mild to moderate - your doctor will closely monitor your eyes to determine when you might need treatment.
2) Advanced disease - treatment options are a) Intra-vitreal injections; b) laser treatment or c) surgery
3. Cataract
What is it?
It is the clouding of the normally clear lens of the eye. Most cataracts develop slowly over the course of many years. The eye functions similar to a camera and like the lens of a camera, if the lens of your eye is blurred, the picture produced has a lesser quality. In India, cataract alone is responsible for nearly two-third of the burden of blindness.
What are the symptoms?
a) Clouded, blurred or dim vision
b) Increasing difficulty with vision at night
c) Sensitivity to light and glare
d) Need for brighter light for reading and other activities
e) Seeing "halos" around lights
f) Frequent changes in eyeglass or contact lens prescription
g) Fading or yellowing of colours
What increase your risk of cataracts?
Factors that increase your risk of cataracts include:
• Increasing age
• Diabetes
• Excessive exposure to sunlight
• Smoking
• Obesity
• High blood pressure
• Previous eye injury or inflammation
• Previous eye surgery
• Prolonged use of corticosteroid medications
• Drinking excessive amounts of alcohol
The best part about human lens is it can be replaced with artificial lens when it becomes cloudy. Therefore, awareness about it and visiting your eye doctor regularly is very essential to prevent this avoidable blindness.
4. Glaucoma- the silent killer
Glaucoma (high eye pressure) is a silent killer. That’s because there are no discernible symptoms in most cases of early glaucoma - nothing to alert you that something's going wrong in your eye. The effect is so gradual that you may not notice a change in vision until the condition is at an advanced stage.
Because vision loss due to glaucoma can't be recovered, it's important to have regular eye examination that include measurements of your eye pressure so a diagnosis can be made in its early stages and treated appropriately. If glaucoma is recognized early, vision loss can be slowed or prevented. If you have the condition, you'll generally need treatment for the rest of your life. People who fail to have routine eye examination and develop glaucoma typically become aware of it only after they’ve sustained permanent vision loss from the disease. And by that time, controlling glaucoma to prevent additional vision loss can be very difficult.
Risk factors for Glaucoma are:
• Having high eye pressure (intraocular pressure)
• Age > 60
• Having a family history of glaucoma
• Having certain medical conditions, such as diabetes, heart disease, high blood pressure and sickle cell anaemia
• Being extremely near-sighted or farsighted
• Having had an eye injury or certain types of eye surgery
• Taking corticosteroid medications, especially eye drops, for a long time.
Early detection of high eye pressure and other risk factors for glaucoma is possible only with routine eye examination by your eye specialist.
5. Sudden loss of vision
There are various causes for sudden loss of vision, but the one most commonly seen in elderly patient with multiple co-morbidities like hypertension, diabetes mellitus, hyperlipidemia (high cholesterol) and cerebral stroke are colloquially term as eye stroke.(retinal vein occlusion).
What is retinal vein occlusion?
A blockage in an artery or vein is called an occlusion or stroke. When the flow of blood from the retina is blocked, it is often because a blot clot is blocking the retinal vein. This condition is called retinal vein occlusion (RVO)
When a retinal vein is blocked, it cannot drain blood from the retina. This leads to haemorrhages (bleeding) and leakage of fluid from the blocked blood vessels into the surrounding tissues.
How does retinal vein occlusion (RVO) cause vision loss?
a) Blood and fluid leaking into the macula cause swelling, a condition called macular edema, which causes blurring and/or loss of vision
b) RVO can cause the retina to develop new, abnormal blood vessels, a condition called neovascularization. These new vessels may leak blood or fluid into the vitreous, the jelly-like substance that fills the inside of the eye. Because of this, small spots or clouds, called floaters, may appear in the field of vision. With severe neovascularization, the retina may get detach from the back of the eye too.
Who can get it?
It is more likely to occur in people with a) Diabetes; b) high blood pressure; c) high cholesterol levels.
Symptoms:
Painless blurring or loss of vision. It almost always happens in just one eye. At first, the blurring or loss of vision might be slight, but it gets worse over the next few hours or days. Sometimes there is a complete loss of vision almost immediately.
Treatment:
a) Intra-vitreal injection of anti-vascular endothelial growth factor (VEGF) drugs
b) Focal laser therapy
c) Pan-retinal photocoagulation therapy
Even if you think you have perfect vision, getting yourself a comprehensive eye examination can be one of the best things you can do to protect your eyesight.
The writer is MS (Ophthalmologist), DNB and Junior Consultant, Department of Ophthalmology, CIHSR, Dimapur.
