Symptoms of a cataract depend on its size, its position and whether it affects one or both eyes. Usually a cataract has only one symptom: gradual loss of vision. There is no pain or discomfort except blurred vision.
In the absence of clear symptoms, the following signs help identifying the possibility of a cataract:
> Problem in reading, recognizing faces, driving and watching television
> Frequent drafts and glares from lights and sun
> Colors appearing washed out or faded
> Frequent changes in glasses or contact lens prescription
It is important to remember that these problems can be caused by other physical ailments too. If a vision problem persists, contact an Optometrist for an eye checkup in order to rule out cataracts.
An optometrist is a health professional who specializes in testing eye conditions.
Cataracts are usually caused by changes in the structure of the eye lens over the years. However, there are factors apart from old age which may increase the risk of cataracts. These include:
> Eye injuries
> Severe inflammation of the eye (uveitis)
> Exposure to the sun’s ultraviolet (UV) light
> Continuous usage of corticosteroids for more than a year
> Excessive alcohol consumption
> Family history of cataracts
Cataracts may also occur in children. Congenital cataracts are present at birth or emerge soon after birth and are caused by infection, improper development or injury.
The types of cataract can be differentiated depending upon the part of the eye lens where it develops.
The three common types of cataracts are:
> Nuclear cataracts: Develops when the center (nucleus) of the lens hardens due to age. When the lens renews itself, the new lens cells are formed outside the existing lens and the older cells are compacted towards the center.
> Cortical cataracts: Develops at the outer edge (cortex) of the lens and moves in towards the center.
> Sub capsular cataracts: Develops at the back of the lens.
Cataracts begin small and may not cause any changes in vision during the initial stages. A cataract grows slowly and gradually and later begins to cover a larger part of the lens; this is when vision becomes dull and blurry. If the cataract is left untreated, it will change the lens to a yellowish brown color and add a brown tint to vision. This tint can decrease the quality of vision.
Cataracts can be diagnosed by an Optometrist using a device called ophthalmoscope.
If you have cataracts, you will be referred to an Ophthalmologist—a doctor that specializes in eye health. The ophthalmologist will offer remedies ranging from self-help measures to surgery.
Self-help: There are a few temporary solutions to reduce the effects of cataracts. Eye glasses and bright lighting can help decrease blurriness for a short time. The cataracts will, however, continue to progress and can be cured only through surgery.
Surgery: Cataracts can be removed by destroying the cataract ridden lens using sound waves and replacing it with an artificial man-made lens called an intraocular lens. This procedure is called phacoemulsification, and is a relatively safe procedure that takes up to 40 minutes. In cases where cataracts affect both eyes, the surgeries will be done at different times for each eye. Normally, there is a gap of 6 to 12 weeks between surgeries. Before the surgery, the doctor will conduct a few tests to measure the cornea curve and the size and shape of the eye. These tests allow the doctor to choose the right type of intraocular lens (IOL). There are a number of types of IOLs available. You should talk to your doctor to ensure the best possible option. The patient will be instructed not to eat or drink anything for 12 hours before surgery. The doctor may prescribe antibiotics and anti-inflammatory drops to be used 2 to 4 times a day after surgery. Cataract surgery is one of the most common surgeries conducted worldwide. 99.5% of cataract surgeries do not have any postoperative complications. About 90% of the patients undergoing surgery report a significant improvement in eyesight after surgery. However, there are still risks and complications that need to be understood.
Risks and Complications
> Excessive bleeding is possible during a cataract surgery but doctors safeguard against this by conducting a list of pre-operative tests. To avoid excessive bleeding during surgery, patients should stop taking any medication that alters blood density, such as blood thinners.
> Infection could occur after the operation. Severe infections can cause loss of vision. To avoid infection, the doctor will prescribe a set of antibiotics and anti-inflammatory drugs. Furthermore, the patient will be instructed on how to clean the eye. It is important to keep the eye clean and wash your hands before touching the eye after surgery.
> Cataract surgery increases the risk of retinal detachment. Retinal detachment occurs when the retina becomes thinner and brittle due to age and begins to detach and pull away from the underlying blood vessels and neurons. Retinal detachment is very rare. However, if it occurs, it can cause permanent loss of vision. Other eye defects such as high myopia (nearsightedness) further increase the risk of retinal detachment after cataract surgery.
> Retinal detachment causes a gradual loss of vision. If not treated immediately, the loss of vision could be permanent. Retinal detachment does not cause any pain or discomfort and is most often disregarded until it is too late. The patient should be cautious of the following symptoms which signal retinal detachment:
> Dark black spots in the field of vision. These spots are called floaters and are the first signs of retinal detachment
Black spots that connect to form cobweb-like structures in the field of vision
> Bursts of light that last for a second
> Retinal detachment is classified as a medical emergency. Anyone experiencing the above symptoms should contact their eye specialist immediately.
Since the cause of cataracts remains unknown, there are no proven prevention methods. The medical research community provides numerous theories about cataracts. This research offers the following preventive methods:
Consume antioxidants: Consuming fruits rich in antioxidants may prevent cataracts. This relies on the theory that protein clumping that leads to blurred vision or cataracts is caused by oxidization of lens proteins.
Have regular eye checkups: Cataracts can easily go unnoticed. Yearly eye checkups help ensure that a cataract is identified and cured in its first stages. Regular eye checkups are important especially in elderly and diabetics because the risk of cataracts is higher.
Protect your eyes from injury: Eye injuries can cause cataracts.
Quit smoking: Research has found smokers are twice as likely to develop cataracts as non-smokers.
Protect your eyes from the sun’s ultraviolet (UV) rays: Wear hats with brims and sunglasses. Make sure your sunglasses offer UV protection (some glasses don’t offer UV protection even if they are tinted; for example, Polaroid glasses do not offer UV protection).