Tuesday, 26 July 2011

Is Surgery for Cataract A Must?

Published in City Times

Surgery for Cataract --- Is it a Must

Cataract is one of the leading causes of blindness, particularly in the developing world, accounting for 40% of blindness in some of these countries. Yet, it is one of the leading causes of correctible blindness in these countries, says Dr.Nadim Habash, Specialist Ophthalmologist, American Hospital, Dubai.

What exactly is cataract? Cataract is increasing cloudiness of the human lens and it may be congenital or acquired. The opacification could be very small, like a spot which is not significant, or it could involve the entire lens and hence there is opacity of the whole lens. The eye lens, retina and cornea together ensure good vision. A problem in any of them, can contribute to cataract. For instance, if the eye lens becomes opacified for any reason, the objects seen are fuzzy. Also, if the retina of the eye is damaged by diseases like diabetes or hypertension, vision becomes blurred. If the cornea is scratched or scarred due to trauma or injury, for example, the vision is yet again blurred.

In majority of people, cataract is a part of ageing and may begin around the mid forties.
The cataract process may be likened to the white of an egg getting boiled! Both, the human lens and the egg white are made up of water and proteins. Once the egg white is boiled, it changes from a transparent to an opaque form. Similarly, when the human body ages, either as a result of the natural ageing process or due to certain diseases, the transparent protein in the eye lens starts becoming opacified in varying degrees. This opacification is cataract and once formed, it cannot be reversed.

While there are various causes for cataract, the commonest cause is due to the chemical changes in the lens that partially result from the normal process of aging. But it is also true that ageing need not necessarily brings on cataract, as revealed by Dr. Azim Siraj, Specialist Ophthalmologist, Jumeirah Prime Medical Centre, Dubai. “For some people with age, cataract appears very late. But in some people this may occur early with age and this is solely gene dependent. Of course, occupation, food and climate have some influence. But these cataracts can rarely occur as early as age 30. But of course there is increasing evidence which points to the fact that cataract today may affect even younger ages of people if they are exposed to ultraviolet light for prolonged periods of time. More exposure to radiation, diet habits and some bio-chemical agents have been identified which result in faster progression of the condition.”

Congenital cataract occurs in children born from marriage between relatives or consanguineous marriages. Also, congenital cataract occurs when a pregnant mother is infected with measles or German Measles or she is malnourished. Childhood cataract may also result from heredity factors or metabolic errors. This is particularly so due to a metabolic disorder called hypo-parathyroidism which can cause cataract in children and young adults. Trauma and injury to the eyes may also result in cataract and this affects both children and adults, reveals Dr.Habash
Dr.Siraj adds, “When the cataract actually forms depends on the type of injury. If the injury is by a sharp object in which the eye is penetrated, the cataract develops instantaneously. But when the injury is a blunt one as caused by a fist or ball striking the eye, it takes time for the cataract to develop.”

So factors causing cataract in adults differ from factors that contribute to the condition in children and young adults, yes? Dr.Habash explains, “Yes. The most common kind of cataract in adults is that which results from advancing age. But there are cataracts that are accelerated by the presence of metabolic conditions, mainly diabetes. Of course, diabetic patients can lives for tens of years and not develop cataract! However, statistically speaking, diabetics are more prone to developing cataract than the normal population. Cataract, in both children and adults, may also be drug-induced, the most common drugs being steroids used in the treatment, particularly of chronic conditions like asthma, arthritis and other ailments.”

What are the general symptoms of cataract?
Dimming of vision is the predominant symptoms. Individuals generally complain of blurred or distorted vision, glare from bright lights and gradual loss of vision. They may show signs of plus or minus eye power, depending on the area of the lens where the changes are occurring. Some people might find night driving a problem because of foggy, fizzy vision.

Is it normal for people to have cataract in both eyes?
Cataract can affect one or both eyes. However, it can be more in one eye than the other. Most often, it is bilateral, affecting both eyes and it is normally more advanced in one eye.

How is cataract diagnosed in children? Dr.Habash emphasizes that children should be routinely examined for cataract and other eye conditions as early as at four or five years. In high risk categories of children, pediatricians may examine for a congenital cataract. Else, diagnosis takes place when vision testing is performed in schools. If a child fails this vision test, he/she must be subject to a full eye examination.

Is surgery the only treatment option for cataract? Dr.Habash explains, “Treatment is always surgical. However, diagnosis of cataract does not mean that the surgery is to be performed immediately. Indication for surgery is not doctor-dependent but patient-dependent because the progression of the condition is not predictable. It can wait until the visual requirements are interfered with. The age at which cataract forms, varies from person to person, being determined by various factors. An individual with 80% cataract may not have any symptoms at all and the condition gets picked up routinely during a check up. Also, its progression is not predictable.

Early cataracts are to be operated upon in people who have high visual requirements like doctors, pilots, engineers and the like. For people who do not have a high visual requirement to carry out routine activities and for those who don’t use the eye for small prints, surgery can be delayed.”

But would not leaving the cataract untreated, cause it to mature faster? Dr.Habash clarifies, “True; it would mature the cataract, but not necessarily, faster. Some people can live for years with very early cataract which does not progress while some individuals will have a faster progression of the cataract. Therefore, to take remedial measures in the latter individuals, follow-ups are needed at regular intervals after initial diagnosis.”

How far spaced would these intervals be? If the cataract is very early and the individual does not have conditions that point towards high chances of it progressing, then we advice these patients to have a yearly checkup of their eyes. But in high risk individuals, as in the case of diabetics or individuals who are on steroid treatment, the checkup will be every six months, says Dr.Habash.

To what extent is laser treatment successful in treating cataract? The most modern and more popular treatment for cataract is called phacoemulsification. It is a procedure which involves the use of ultrasound to fragment the opacified lens into small particles and aspirating them out and then replacing the eye with an artificial lens. Laser is used to perform the same thing. Laser in the treatment of cataract is yet to be used on a large scale, says Dr.Habash.

Cataract is neither preventable nor reversible, emphasizes Dr.Siraj. Yes, but it is possible to prevent some of the risk factors contributing to the condition. These include taking adequate measures to protect oneself from prolonged exposure to direct sunlight and by using good quality ultraviolet lenses, having regular eye checkups in case patients are on steroids or other drugs for chronic ailments and by taking appropriate dosage of the prescribed drugs. Parents should exercise caution while getting toys for their children and avoid getting sharp edged toys like water guns, darts and remote controlled toys with antennas sticking out of them. Older children, especially those wearing glasses, should use protective headgear while playing sports like cricket, emphasizes Dr.Siraj.


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