Cataract

Q. What is a cataract?

A. Any opacification of the human lens of the eye is called a cataract. The human eye is like a camera – the front portion, which is clear and transparent, is called the cornea. This corresponds to the front glass of the camera. The lens is biconvex, exactly like the lens of a conventional camera and is situated behind the pupil of the eye (the jet-black window in the brown/blue/green iris of the eye). It is made up of protein and water and is normally transparent. Due to aging process, these lens proteins coagulate, losing their transparency over time. Certain drugs such as steroids as well as certain diseases such as diabetes hasten this biochemical change. Several studies blame pollution, cigarette smoking and prolonged exposure to the ultraviolet rays of the sun as some causative factors. The reason it occurs in some people at 45 while others live to be a 100 without developing any cataract is at present unclear. Whenever we doctors cannot give a logical explanation, we normally say there must be a genetic factor either causing the development of cataract or preventing it in different sets of patients.

Q. Is there a medical treatment for cataract?
A. Unfortunately,(for patients – fortunately for eye doctors!) there is no scientifically proven medical treatment for cataract. There are plenty of grandmother’s remedies touted as cures or preventive treatments, such as honey, certain vegetable extracts, cow’s urine and even auto-urine therapy. None of them work. There are also a host of eye drops made by homeopathic and ayurvedic companies which burn and sting on application (besides burning quite a hole in the pocket!), which claim to stop the progress of cataract. None of them work. The reason they become popular is many a time the cataract can stop progressing or remain stationary for years on its own, for reasons, which are unknown. If at that time the patient is using any of the above remedies, he will tell a minimum of 50 people about the miraculous drug or therapy, convinced that that is the reason for the lack of progress of the cataract. Unfortunately, patients who are on no therapy and have non-progress of their cataracts are never known to brag!

Q. Does every cataract need to undergo surgery?
A. Just as every one does not have to climb Mount Everest just because it is there, so also you do not have to undergo cataract surgery just because your doctor has diagnosed that you have a cataract. The indication for cataract surgery is when the cataract has progressed to such a stage that it hampers your day-to-day or routine activities. This varies tremendously from person to person. If you live in the US of A for example, and the cataract causes you glare and difficulty in night driving, your eye surgeon may advise surgery the next week. This is because you are probably living alone or with your spouse and if you cannot drive at night, you are considered handicapped. In case you have a medical emergency at night and have to drive to the chemist or hospital for treatment you would otherwise be in a soup! In India however, in most cities, you would be able to use a taxicab or would be able to ask your other relatives living with you or a phone call away, to take you to the hospital! A 50-year-old busy executive may feel handicapped if he finds it difficult to read the fine print in important contracts that he has to sign daily. A 75 year old housewife with a much more advanced cataract may have no complaints as she is able to see the big print of her religious books easily and is not interested in the “rubbish” they show on TV! For the executive, his early cataract may require surgery, while for the housewife, I may ask her to see me after a year for reassessment!

Q. Some people say that if I delay my cataract surgery, it may become too ‘ripe’ or may ‘burst’ and I may lose the eye permanently or it may become too ‘hard’ causing difficulty in surgery later. How true are these statements?
A. Not true. A cataract is considered ‘over-mature’ or in danger of rupture only if it is pearly white in appearance or the vision has dropped such that the patient can only see light projected into his eye but cannot recognize objects even if shown from a distance of less than one meter. As long as you are showing your eye to the ophthalmologist every 6months to a year, he will be able to guide you for surgery long before that stage is reached. As far as hardening of a cataract is considered, it is true that brown and black cataracts can harden over time, making their surgery technically a little more difficult. However, with modern day methods of cataract surgery, they no longer pose a problem to the experienced cataract surgeon.

Q. Now that I have decided to have my surgery done, what are the different options available? Which method is the “best”?
A. If you have trust in your ophthalmologist, it is wisest to allow him to decide what method of cataract extraction he should use for your eye. It depends on the type of cataract. The procedure he chooses depends on many factors, e.g. the type of cataract you have, his experience, and his familiarity with the phacoemulsification machine etc.

Q. Now that you mention it, what is ‘phacoemulsification’? How does it differ from ‘laser surgery’ for cataract, which my neighbour has undergone and paid a large sum for?
A. Phacoemulsification is the use of a machine to which is attached a probe, a pencil like instrument which vibrates at a very high frequency emitting ultrasonic energy. This breaks up or emulsifies the lens (Greek ‘phakos’=lens and ‘emulsify’ is to liquefy) into tiny bits, which are then sucked out through tiny openings in the same probe. This is what the lay public refers to as ‘laser surgery’. In actual fact there is no use of the laser at all for cataract removal in these machines! Probably a few black sheep in the ophthalmic fraternity who do not have the time to explain Phaco-emulsification to their patients or do not feel their patient’s I.Q. level will allow them to understand such big words, combined with some inaccurate and exaggerated stories in the press have helped spread the myth of ‘laser cataract surgery’. For the record, let it be said that there are a handful of genuine laser machines, which are combined with Phacoemulsification machines for cataract surgery. However, at the current time, laser machines take more time, cannot remove hard cataracts and therefore have proved very unpopular with the vast majority of cataract surgeons.

Q. What are the other methods of cataract surgery?
A. Some surgeons are very adept at using the phaco machine and would be able to manage to remove all cataracts using this machine. Others use the Phaco machine for most cases and may use ‘a non-phaco method for certain types of cataract such as very hard cataracts or even very soft cataracts which can sometimes be a little difficult to remove safely using the phaco machine. Still others may not be conversant with the phaco machine at all and may remove the cataract by non-phaco means in all cases. In non-phaco methods, there are some who will use a small ‘sutureless incision’ to enter the eye, while others will use a larger incision which will require to be closed with stitches.

Q. Is any method superior to the others?
A. That is a loaded question! The method using phacoemulsification and the small incision non-phaco method are both ‘sutureless’. Hence healing is rapid. Usually in about a week or so, the patient is seeing fairly well and is able to go back to a fairly normal life with no restrictions. In larger incision surgeries, where sutures are taken, the patient may have some restrictions on having a shower etc. It may also sometimes take a month to 6 weeks to regain good vision. In a small percentage of ‘sutured’ cases, there may be a slightly higher ‘astigmatism’ or cylinder number left over at the end of 6
weeks compared to the sutureless surgeries. However, in a majority of patients at the end of 6 weeks, there is almost no difference in the appearance of the eye or the best-corrected visual acuity irrespective of which method was used. Hence the choice of method may sometimes also depend on the lifestyle of the patient. Taking the previous example of the busy executive who needs to go back to office as soon as possible after the surgery, it may be preferable to do a phaco or a sutureless surgery on him. For the 75-year-old housewife, any of the procedures would be acceptable. Hence this decision is best taken jointly after discussing the pros and cons with your eye surgeon.

Q. What about the IOL (Intra-ocular lens) implant? How safe are they? What is the life span of the IOL? Are imported IOLs superior?
A. The IOL is a thin plastic or acrylic lens. The first ones were put shortly after the Second World War. They then became unpopular due to a high complication rate. They were then modified and the present type has been in use since the early eighties. In the present day, almost 100% of cataract surgeries the world over are done with the simultaneousimplantation of an IOL including most eye camps. They are extremely safe and are well tolerated by the body. There is no rejection of the material of the lens, which is biologically inert. Judging from the complete lack of complications in the vast majority of well-done surgeries over the past 2 decades, it is safe to extrapolate that there should be no problems due to the lens for the average life span of the patient. As regards the controversy of Indian versus foreign IOLs, I have no hesitation in saying with pride that Indian IOLs have come of age. They are as good as and in some cases even superior to the imported variety and are even being exported to over 50 countries including Europe and the Americas. However, as
with most other gadgets and gizmos, there is the craze for foreign IOLs in the patient population, which we eye surgeons happily satisfy, as the patient does not mind paying a bit more for an imported IOL! However, there are some special IOLs such as specially coated IOLs for use in patients prone to inflammation, which are still not manufactured in India.

Q. What is the difference between rigid and foldable IOLs? What are multifocal IOLs?
A. Rigid IOLs are usually made of a medical grade plastic called PMMA and have a maximum width of 5to6mm.. Hence to insert them into the eye, the incision in the eye also has to be approximately the same size. They can be inserted after any type of cataract surgery. The foldable IOLs are made of acrylic or silicon material and can be folded so as to enable them to be slipped into the eye through a smaller incision, even as small as 3mm. These can only be inserted after cataract surgery by phacoemulsification. Research is in progress to mass manufacture IOLs, which can be put in through still smaller incisions. The smaller the incision, the less chance for astigmatism or cylinder number induced by the incision. Multifocal IOLs are special IOLs, which can correct both, distance and near vision hence reducing the patient’s dependence on glasses for both distance and near. They are a little more expensive than the other IOLs. However, not all patients are suitable candidates. It is best to discuss the pros and cons of the type of lens to be inserted with your ophthalmologist before the surgery. The costliest option is not necessarily the best option for all patients.

Q. There are some latest “yellow” IOLs. What are they?
A. They are coated with a special pigment to give the patient more natural vision, especially for night driving. They are at present among the most expensive foldable IOL available in the market.

Q. What about anaesthesia for the surgery?
A. Most surgeons would operate you under local anaesthesia. This involves giving you a tiny prick with a very fine injection needle around the eye along with some local anaesthetic eye drops. At the end of surgery, a patch is applied to keep the eye closed. This is removed a few hours later or the next day, by the surgeon. Some surgeons prefer (in very co-operative patients) to give only topical drops anaesthesia, with no injection around the eye. In such cases, there is no need to patch the eye following surgery. However, serious complications can sometimes occur if the patient inadvertently moves the eye or blinks hard during the surgery. It is best to discuss this aspect too with the surgeon before surgery, to prevent him from blaming you for any mishap later. Make sure, in case the surgeon is going to use only topical anaesthesia, that he is well experienced and is not doing this only to impress you! A tiny, tiny percentage of eye surgeons claim to operate patients with no anaesthesia at all, not even topical drop anaesthesia. Thankfully, the tribe of such surgeons is not growing.

Q. How soon will I start to see clearly after the surgery? Will I need glasses after the surgery?
A. It depends on the type of surgery. If you have had surgery with topical anaesthesia, you will see reasonably well immediately after the surgery. For those who have been patched, they will see reasonably well on removal of the patch. Some eye surgeons prefer to leave an air bubble in between the cornea and the implant after the surgery, for added safety. This air bubble can considerably blur the vision for up to a week post operatively. If your surgeon has taken sutures to close the incision, clarity may come only after a month or so. Most patients will develop a small number for distance and for near after the surgery and will need glasses to see clearly, though not of high number. It is wise to wait for a month or 6 weeks after the surgery for the number to stabilize before having glasses made, especially if stitches have been taken during surgery.

Q. What are the dos and don’ts after surgery?
A. This is very individual and varies from surgeon to surgeon. However, the number of don’ts has dropped drastically over the years, as cataract surgery got safer. Most surgeons allow you a head bath about a week after the procedure. In case stitches have been taken, you may be asked to wait a bit longer. You can read, write, watch TV, fight with your spouse, shout at your kids almost immediately after the surgery. There is usually no restriction in your diet. You do not have to stop most medication you have been taking for any other medical condition. However, if you are on aspirin, for thinning the blood, please mention it to your eye doctor. He may ask you to stop these tablets a few days before and after the cataract surgery. Your anti-diabetic pills may have to be omitted on the morning of surgery.

Q. My neighbour saw well after her surgery for 6 months. Now vision is getting blurred. Her doctor has advised her ‘YAG laser treatment’. What does this mean?
In a certain percentage of patients, the bag or capsule in which the IOL is placed can become opaque with time. This may happen as soon as one month after surgery or even many years following the surgery. In a majority of patients it does not happen at all. This can occur even after excellently done surgery. It is not considered a complication of surgery but as an unpredictable side effect, which results in haziness of vision. This is corrected by a painless 5-minute procedure called “YAG laser capsulotomy” in which an actual laser is used to burn a small hole in the centre of the capsule or bag, so as to restore vision. This is a one time procedure, which does not usually have to be repeated.

Q. Can a person operated for cataract donate his eyes after death?
A. Most certainly he can. Though the whole eyeball is removed at the time of eye donation, what is used is only the transparent layer in the front of the eye, called the cornea (this is like the transparent glass in front of a wrist watch). This is normally unaffected by successful cataract surgery, hence this cornea can restore sight to a blind person after successful cornea transplant surgery.