Our eyes are the torches of our body. They are our natural mirrors, windows and cameras. Without our eyes, our entire existence will be shrouded in utter gloom and audio format. Without our source of sight, we will hear faceless people laughing and simultaneously be unsure of the cause of their laughter. Without our pair of vision slits, we will not be able to see reality and at the same time we will be incapable of viewing our dreams.
Thus, the eyes are one of the organs of the body that we never hope to lose.
However, the disease called ‘cataract‘ does not share our view, even though it rents our eyes.
It is an undeniable fact that cataract is the major cause of blindness worldwide.
This article was written with the intent of being educative and informative.
Please note that it is NOT an instruction manual on how to treat cataract.
The part that deals with the treatment of cataract is aimed at giving cataract patients and people who are friends or family members with cataract patients, an insight on what they are to expect during the treatment of cataract.
WHAT IS CATARACT?
Cataract is the cloudiness or opacity of the natural (normal) lens of the eye.
According to the Mayo Clinic, “for people who have cataracts, seeing through cloudy lenses is a bit like looking through a frosty or fogged-up window.”
Hence, when the lens becomes cloudy, light rays cannot pass through it easily and vision is blurred.
WHAT IS LENS?
The lens is a biconvex, transparent and elastic structure of each eye, located behind the pupil, whose function is to refract the light rays coming in through the pupil and focus the image of the objects viewed onto the retina.
SITUATION OF THE LENS:
The lens is situated within a sealed capsule, behind the pupil and before the retina.
CAUSES OF CATARACT:
Generally, age is the leading factor of cataract. At old age, old cells die and accumulate within the capsule of the lens.
Over the years, accumulation of old cells in the capsule brings about the accumulation of fluid and denaturation of protein in the lens fibers, thereby causing cloudiness of lens and consequent blurred image.
In addition to that, cataract develops due to many other causes such as:
1. Eye injuries.
2. Previous eye surgery.
3. Diseases such as diabetes, Wilson disease and hypocalcemia (low blood calcium level).
4. Long-term use of drugs such as steroids, diuretics and tranquilizers.
6. Family history.
7. Diet containing large amount of salt.
8. Long-term unprotected exposure to sunlight.
9. High blood pressure.
SYMPTOMS OF CATARACT:
A person can detect or suspect they have contracted cataract through the following signs:
1. Sensitivity to light and glare (an intense, blinding light).
2. Painless blurred vision.
3. Poor night vision.
4. Double vision (a condition in which one perceives two images) in affected eye.
5. Need for a bright light while reading.
6. Fading or yellowing of colours.
7. Seeing “halos” around light.
TYPES OF CATARACT:
There are 4 known types of cataract, which include:
1. Nuclear cataracts:
These are cataracts affecting the center of the lens.
At first, they may cause more shortsightedness or even a temporary improvement in the night vision of the sufferer. But with time, the lens gradually turns more densely yellow and further clouds their vision.
2. Cortical cataracts:
These are cataracts that affect the edges of the lens.
They usually begin as whitish, wedge-shaped opacities or streaks in the outer edge of the lens cortex. As the disease slowly progresses, the streaks of cloudiness extend to the center of the lens.
3. Posterior subscapular cataracts:
Posterior subscapular cataracts are cataracts that affect the back of the lens.
They are the fastest spreading type of cataracts.
4. Congenital cataracts:
Congenital cataracts are the inborn cataracts. That is; cataracts present from the time of birth.
They can be genetic or associated with intrauterine infection or trauma.
TREATMENT FOR CATARACT:
The only treatment for cataract is surgery. The common methods of treatment are:
1. EXTRACAPSULAR EXTRACTION METHOD:
This is an old technique.
In this technique, a 12mm incision is made into the eye under an operating lens, to remove the whole lens.
Meanwhile, the posterior capsule of the lens is left to hold an Intraocular Lens (IOL) implant which is used to replace the faulty natural lens.
Subsequently, multiple sutures (stitches) are required to seal the eye after the surgery. The suture must be perfect to prevent astigmatism (a disorder of vision which involves the improper focusing of light on the retina, therefore creating a blurred image) from developing.
2. PHACOEMULSIFICATION METHOD:
This is the current technique.
In this method, the cataract is broken into smaller fragments by ultrasonic radiations.
First of all, a 3mm incision is made in the eye.
Next, an ultrasound or laser probe is used to break the cloudy lens without damaging the capsule.
Furthermore, the lens fragments are aspirated out of the eye.
Then, a foldable Intraocular Lens (IOL) is introduced through the incision.
After entering the eye, the lens unfolds to take position inside the capsule.
No sutures are needed when applying this method, as the incision is self-sealing.
PREVENTION FOR CATARACT:
Though no studies have proven how to prevent cataract, the risk of developing cataract can be substantially reduced by:
1. Having regular eye examinations.
2. Quitting smoking.
3. Managing other health problems.
4. Choosing a healthy diet that includes fruits and vegetables.
5. Reducing alcohol intake.
6. Wearing sunglasses.
I hope with this article I have been able to educate you on the overview, symptoms, causes, types, treatment and prevention of cataract.
Did you learn something new today?
1. Essentials of Medical Physiology by K and Prema Sembulingam.
2. Mayo Clinic