The human eye is constructed in much the same way as a camera, with the lens to focus the light onto the retina, which is the equivalent of the film. The retina then transmits the focused image to the brain via the optic nerve.
Cataract is cloudiness of the lens and it causes vision to deteriorate. Before this happens, it is common for the eye to become progressively short sighted so that frequent change of glasses becomes necessary. The eye is more sensitive to light and glare and you may see ghost images
When glasses can no longer help sufficiently and when the patient has significant problem with his/her vision while reading/driving/watching television, the only effective treatment is to remove the cataract and to replace it with a plastic lens The power of the lens to be implanted is assessed before the operation.
Here the cut made is 2.5 mm and is self sealing. The cataract is broken into small pieces using ultrasound energy and sucked out. The artificial lens implant is then folded and inserted through the same small cut-it opens once inside and is rotated into its position
Here a 10mm cut is made and the entire cataract is removed as a single piece. An artificial lens is implanted in its place and the cut is closed with sutures. This is almost never done nowadays.
The advantages of phacoemulsification are that the wound is very small and heals quickly-thus recovery of vision is faster (1week on an average) and the restrictions after surgery are minimal. However it is not suitable for all types of cataract and the final decision as to the type of surgery best suited to your cataract should be taken after discussion with your doctor.
Single vision lenses, these lenses take the place of your cataract and can help you see distant objects. However, these lenses will not correct astigmatism and will not correct near vision, so it is likely that you will need to wear glasses at least part-time for distance activities and full-time for near work.A monofocal lens can be adjusted for near/distant vision, not both at the same time. In case both eyes are due to undergo surgery a short duration apart, having one eye distance corrected and one near corrected may allow freedom from spectacles(monovision)
In addition to correcting nearsightedness or farsightedness, toric lenses have the ability to correct astigmatism. If you have significant astigmatism before surgery, then this lens option will provide you with a better opportunity to have clear distance vision without glasses. Toric lenses still correct primarily distance vision and will not correct near vision.
These are designed to minimize aberrations giving better contrast.
Multifocal lenses are appropriate for some patients who have a strong desire to see distant and near objects without glasses and are willing to somewhat compromise the quality of their vision(in the form of reduced quality night vision, including glare and halos, less sharpness of vision than may be obtained with monofocal IOL and spectacles) to obtain freedom from glasses. Multifocal lenses may require some time for adaptation, and in very rare cases, the vision obtained with multifocal lenses may be so poor that replacement of the lens with a monofocal lens may be necessary. This is a separate procedure for which there will be a charge, and it carries additional surgical risks.
As is true of any surgery, cataract surgery is never 100% risk free. However owing to many advances in techniques and technology the surgery is now very safe.
Rare problems include:
These are uncommon and can all be rectified, though it may require additional surgery for the same
Once a decision to perform cataract surgery has been taken you will be required to undergo routine blood and urine tests and get a physical check-up done to ensure you are fit to undergo the surgery. You will be given medicines and eye drops which are to be started a couple of days before the surgery. The measurement of the power of the lens to be implanted will be determined The operation is done as a day case-that is the patient comes to the hospital in the morning on the day of surgery and goes home the same afternoon. It is only occasionally that the patient stays overnight after the surgery-usually when the patient is from another town/stays far away.
The operation is done under local anesthesia-small injection is given beside the eye which is associated with some discomfort-thereafter, there is no pain Since the patient is awake, he/she can feel the surgeon and assistant working around his eye. There may be some sensation of touch/pressure but the surgery is pain free. The patient’s head is covered with sterile drapes but the patient is able to breathe comfortably. It is important that the patient lies still and does not move around as this makes surgery difficult. During the surgery the cataract is removed leaving behind a transparent bag into which the plastic lens is then implanted. The surgery takes about 15min but may take longer depending on the hardness of the cataract and associated problems like poor dilation of pupil. If the cataract is being removed by phacoemulsification the patient may hear the noises made by the machine.
The patient’s eye is checked after 4 hours when the eye pad is removed. Thereafter the patient needs to wear dark/ protective glasses for a few days to protect the eye from too much light while it is healing. The vision usually is quite clear by the end of the week, though glasses are required for reading and watching television. These are prescribed once the wound heals. For the first two weeks after the surgery, patient should not have a head bath or wash his/her face. The face can be wiped with a clean wet towel. The eyelids should be cleaned daily with moist sterile cotton. The patient will be asked to use two or three types of eye drops after surgery-initially frequently and later with decreasing frequency. These drops are likely to continue for 1 month. Follows up visits are at weekly intervals though more frequent visits may be required in some patients.
IF AT ANY TIME YOUR EYE BECOMES VERY RED AND PAINFUL OR THERE IS A DROP IN VISION-PLEASE CONTACT THE HOSPITAL IMMEDIATELY AT 25463362/98505 33847
Sometimes a gradual blurring of vision occurs, months or years after cataract surgery because of clouding of the capsule on which the lens is supported. This is called “after cataract” and is easily treated with a laser procedure taking 10minutes, following which the vision improves again -to what it was with glasses soon after cataract surgery.
IF YOU HAVE ANY MORE QUERIES, PLEASE ASK THE DOCTOR.