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How is cataract diagnosed?
Do I have a cataract?
Treatment of cataract?
What is phacoemulsification?
Types of Intra ocular lenses?
Complications of cataract surgery
Surgery for accompanying eye problems
How to put drops?
Post operative/after surgery care?
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How Are Cataracts Diagnosed?
During an examination, the eye professional is able to observe cloudy areas on the lenses, even before the cataracts begin to interfere with vision.
Various vision tests are performed. To determine how clearly a person can actually see, the familiar Snellen eye chart is used, with its rows of letters of decreasing sizes. From a specified distance, usually 6 meter, a person reads the letters using one eye at a time. If a person can read down to the small letters on the line marked 6 meter, then vision is 6/6 . If a person can read only down through the line marked 12
metres, vision is 6/12; that is, from 6 metre the patient can read what someone with normal vision can read from 12
metres.
Although these tests aid in making a diagnosis for cataracts, they are not useful for determining whether a patient actually needs cataract surgery. All current eye tests have limitations. They can only determine whether problems exist; they cannot determine their causes, which could be from any number of disorders, including cataracts. Other eye disorders must also be ruled out if vision seems abnormal. In addition, eye tests do not necessarily indicate how effectively people function at home. Some people with cataracts perform poorly on the tests yet appear to have no difficulty functioning normally day-to-day. Others perform well on the tests but insist that their eyesight is bad enough to curtail ordinary activities, such as driving. In general, even if cataracts are diagnosed, the decision to remove them should be based on the patient's own perception of vision difficulties and needs and the effect of vision loss on normal activity. The patient should also be aware of all the risks and costs of surgery before a decision is reached
How do I know if I have a cataract?
People who have cataracts often notice a decrease in their vision. For example, they may have difficulty reading or driving. Another common problem is glare. Because of glare, people with cataracts may find it harder to see when there are bright lights on, such as when looking at the oncoming headlights of a car. An eye physician can tell if you have a cataract by examining your eyes.
How are cataracts treated?
People often think that cataracts can be removed with a laser. This is not true. Cataracts cannot be removed with a laser. In addition, there is no medicine one can take to treat a cataract. Cataracts are treated by microscopic surgery. In cataract micro-surgery, a tiny incision is made in the eye and the cloudy lens is removed through this opening. The technique that is most often used is called ‘Phacoemulsification’ which uses the principle of ultrasound to dissolve the cataract inside the eye. The dissolved material is then aspirated through a built in suction mechanism. The empty space thus left behind is replaced with an Intra ocular lens. The lens may be folded and inserted into the eye through the microincision (in case of foldable lenses). In some cases non-foldable lenses may have to be used after extending the incision size. Following cataract surgery, most people will experience substantial improvement in their vision. |
What is
Phacoemulsification?
Phacoemulsification has gained in popularity in recent years, and is now the preferred form of cataract removal. Although this procedure has been available to us for a long time, recent advances and refinements in machine and microsurgical instruments have made it safer and more effective than previously.
The technique of phacoemulsification utilizes a small incision. The tip of the instrument is introduced into the eye through this small incision. Localized high frequency waves are generated through this tip to break the cataract into very minute fragments and pieces, which are then sucked out through the same tip in a controlled manner. A thin 'capsule' or shell is left behind after cleaning up of the entire opaque cataract.
 The incision size for phacoemulsification is approximately 3.0 millimeters in width. If a lens implant that can be folded is used following removal of the cataract, this incision may not have to be enlarged. If a lens is used which cannot be folded, the incision must be enlarged to 5.0 or 5.5 mm.
Are the stitches required after
Phacoemulsification?
The incision (wound) required for phacoemulsification is small (3 mm) and the wound construction is such that it is self-sealing. Therefore a surgery in which a foldable lens has been implanted through the small 3 mm wound, generally does not require any stitch, as it is watertight. The surgeries in which the wound has been enlarged (5 or 5.5 mm) to put a lens that cannot be folded, is likely to require one stitch, because the wound is larger.
In addition, some surgeons simply prefer the safety of having the incision sutured, even if the incision is already watertight. The best procedure for a patient is usually the one with which his or her ophthalmologist feels the most comfortable, since these variations of cataract surgery are all quite effective.
What are the advantages of Phacoemulsification over routine extracapsular surgery?
In a conventional surgery the incision required is larger (10-12 mm) and requires stitches for closing. This larger incision takes 6-8 weeks to heal. Moreover, the stitches can cause distortion of the normal curvature of the cornea (the clear part of eye) and thus lead to astigmatism and blurred vision because of this.
Essentially all the advantages of phacoemulsification are because of small incision, which is self-sealing. The wound is more stable and the chances of wound complications are minimized. The patients can resume their normal activity faster as compared to conventional extracapsular surgery. The wound healing is faster and more predictable, and therefore glasses can be prescribed much earlier as compared to the conventional surgery. The patient requires less follow up visits for checkups. As the incision is small and in many cases stitches are not required, the cornea does not get distorted and therefore the chances of significant astigmatism is minimized.
Types of Intra Ocular lenses?
These lenses are permanent lenses intended to be put inside the eye. There are 3 major factors in type of lenses:
1 foldable and non foldable lenses: In most cases, the cataract is removed by phacoemulsifictaion surgery through a 3mm incision. Now a lens has to be implanted in this empty space. A lens is normally about 6mm in diameter. Since the entry site is only 3 mm,a 6 mm can’t be inserted through this small opening. So a special material lens was designed which could be folded into half its size outside the eye, inserted through the 3mm opening; and the lens then unfolds itself again into 6mm size once it is in the eye.Thus a 6mm lens is able to go through a 3mm opening.
Foldable lenses are more costlier than non foldable lenses. Retaining the small opening of 3mm has its advantages of minimum cut, faster healing, lesser post operative number, less foreign body sensation after surgery. However,in some cases it may not be possible to put foldable lenses even if desired because of the special condition of the eye or cataract.
2 Hydrophobic and Hydrophillic foldable lenses: are types of foldable lenses.Generally hydrophobic lenses are better than hydrophilic lenses and especially so in diabetics,uveitis or other compromised situations.
3 Multifocal lenses-are meant for providing convenience of not wearing bifocal glasses after surgery at the cost of quality vision for distance and near. If one does not mind to have less sharp vision for distance and near vision but would wants to get rid of bifocals, this would be a suitable option to consider.
Complications of Cataract Surgery and
Post-Surgical care
Modern cataract surgery is one of the safest of
all surgical procedures. In 2% to 4% of cases, however, complications occur, including swelling, detachment of the retina, glaucoma (high internal eye pressure), infection, and displacement of the new lens. Some can be serious and cause poorer vision than before surgery or even blindness in the operated eye. Some complications require extensive, additional surgery on the eye. Complications can appear immediately after cataract surgery or develop at a much later date.
The risks are greater in people who also have other eye disease or serious medical problems, such as heart or respiratory disease or diabetes, for which they may be taking strong medications. Either the diseases or the medications can increase the risks. People with diabetes who also have retinal diseases are at particular risk for complications, which can largely be prevented if the accompanying eye diseases are treated either before or shortly after the cataract procedure.
Inflammation and Infections. Postoperative inflammation is a common problem and infections occur in about one in several thousand operations. Inflammation after cataract surgery can be a problem. Although most people are able to go home the same day that they have cataract surgery, they need to have someone drive them home and stay with them for a few days until their vision is acclimated. Vision usually remains blurred for a while but gradually clears over a 4- to 10-week period. The ophthalmologist usually recommends dark glasses over the eye to protect it during the healing process. The eye can be cleaned gently using a washcloth dipped in warm water without soap. It is very important not to press or rub the eye during this procedure. An eye shield may be placed at night.
The ophthalmologist will also prescribe antibiotic and anti-inflammatory eyedrops to protect against infection and reduce swelling. Physicians often administer topical applications of combinations of a corticosteroid (commonly called steroids) with an antibiotic for controlling inflammation after surgery.
Corticosteroids, however, increase the risk for pressure in the eye and infection, and one study reported reduced visual acuity with the use of steroids compared to antibiotics. Nonsteroidal anti-inflammatory drugs, such as
diclofenac, ketorolac, and do not pose these risks and may be effective alternatives to steroids.
Glaucoma as a Complication. Cataract surgery can cause glaucoma, a condition that causes the pressure of fluids inside the eye. It is very important to minimize vigorous exercise and any activity that increases internal eye pressure. Postoperative cataract patients should put on their shoes while sitting and without lifting up their feet. They should kneel instead of bending over to pick something up. Lifting should be avoided. Reading should be limited, since it requires eye movement, but television is all right. Sleeping positions should be on the back or on the unoperated side.
 Secondary Cataracts (Posterior Capsular
Opacification). Between 30% and 50% of the people who undergo extracapsular cataract surgery develop a secondary "after cataract" when cell growth occurs on the back of the capsule itself (called posterior capsular
opacification). In about 25% of patients it occurs within two years of surgery. The capsule gradually becomes cloudy and interferes with clear vision the same way the original cataract did. It is the most common post-surgical complicationTo date, there are no safe methods for preventing this common occurrence.
Treatment for Secondary Cataracts (Posterior Capsular pacification):
Laser Surgery. The standard procedure for secondary cataracts is a form of laser surgery known as a YAG
capsulotomy. (Capsulotomy means cutting into the capsule, and YAG is an abbreviation of yttrium aluminum garnet, the laser most often used for this procedure.) This is also an outpatient procedure and involves no incision. With the laser beam, the ophthalmologist makes an opening in the clouded capsule to let light through. After the procedure the patient should remain in the doctor's office for an hour to be sure that pressure in the eye is not elevated; an eye examination for any complications should follow within two weeks.
Laser surgery has become so commonplace, that some ophthalmologists use it after cataract surgery to prevent later clouding. However, laser surgery carries its own risks and possible complications, similar to those of cataract surgery itself, which can also lead to poorer vision or blindness. About 2% of those operated on develop a detached retina, four times the risk of those who undergo cataract surgery. In some people, particularly those with glaucoma or who are severely nearsighted, the pressure in the eye may increase after laser surgery. It is strongly recommended therefore that this surgery not be performed for prevention, but only if the lens capsule clouds up again.
Macular Degeneration. In one five-year study, people who had undergone cataract surgery had twice the risk for progression of age-related macular degeneration. (This is a common cause of vision loss in the elderly, in which the retina breaks down.) Interestingly, a recent study reported that cataract surgery significantly helped patients who had existing macular degeneration. More research is needed to refute or confirm this finding.
Other Rare Complications. In rare cases, the retina at the rear of the eye can become detached. Infections or bleeding can develop inside the eye, and the cornea can swell or become cloudy. The surgery itself can produce astigmatism (visual problems caused by an irregularity of the cornea). An implanted IOL can become damaged or dislocated. In some cases, pupils become
atonic, in which glare becomes intense.
Surgery for Accompanying Eye Conditions
Cataracts and Glaucoma. Patients with both glaucoma and cataracts may need three procedures for both eye conditions. The procedures are usually primary trabeculectomy for glaucoma and
phacoemulsification, and intraocular lens implantation for cataracts. Fluid leakage and the presence of blood in the back chamber of the eye are potential complications of this combined procedure
Cataracts and Corneal Disease. Patients who have both cataracts and corneal disease may be given either a single operation that combines three procedures or one that uses two procedures sequentially. The combined procedure has been used since the late 1970s and employs extracapsular cataract extraction and intraocular lens insertion with corneal transplantation. The other option performs the cataract procedures and the corneal transplantation sequentially. Recovery of vision is usually much more rapid after the simultaneous triple procedure than after the sequential procedures, which can delay recovery of visual acuity for over a year. In general, however, there appear to be much higher complication rates, such as posterior capsule rupture and eye fluid loss, after the combined procedure than after separate procedures. Postoperative refractive errors, which result in abnormal distribution of light patterns, are also more common after the combined procedure. The rate of these errors depends on the skill of the surgeon and the power of the implanted lens. Although performing the procedures sequentially also carries certain risks, notably a higher rejection rate of the implant, many experts recommend that for most patients the sequential operation may be the better option.
Using Eye Drops and Ointments
What is the best way to put eye medication in my eye?
Eye medication can be applied very simply by following some basic instructions. Always wash your hands first. Shake the medication bottle if indicated on the label. Open the bottle or tube being careful that its tip does not touch anything. Pull your lower eyelid down with the tip of your finger and look up. Some people prefer to look in the mirror while doing this or an assistant puts drops in the eye with patient lying down in a straight position. Squeeze one drop or 1/4 inch ribbon of ointment into the bottom lid, trying not to touch the lid with the tip of the bottle or tube. Close your eye gently for 5 minutes to allow the medication to absorb. Residual ointment on your lids may be wiped away with a tissue. The bottle or tube should be re-capped. You should check the label to see whether refrigeration is required between doses.
A slight stinging sensation may be present after using your medication. In addition, eye ointments will temporarily blur the vision. When using multiple medications, wait a few minutes (15 minutes) between each application to ensure that the eye has time to absorb each. If your eye doctor has prescribed a combination of eye drops and ointments, and you are scheduled to put them in at the same time, always use the drops a few minutes before the ointment. This helps the eye drop penetrate the eye without hindrance from a thick layer of ointment.
Should I clean my eyelids before using eye medications?
Cleaning the lids may be helpful if an accumulation of crusting or discharge is present. An effective way to do this is to wet a cotton ball with warm water and gently wipe the lid from the inner corner in an outward direction with the eye closed without putting pressure on the eye.
Post operative/after surgery care Instructions:
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All instructions are for more or less 3 weeks with a flexibility to allow one to adapt ones individual needs as per comfort levels and requirements. A little redness, watering and irritation are normal in all patients but please inform us if any of these are in out of proportion.
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You can watch TV and read newspaper from 3rd day and 15th day respectively with a tape covering the glass of operated eye or with a zero numbered or presecribed numbered glass
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Avoid as much as possible for sleeping on the operated side for 3 weeks. No head bath for 1 week but can have bath below neck from day1.Shave allowed from day1.
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No direct washing of eyes for 1 month. You can sponge your face.
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Before putting drops, wash your hands with soap and water. Don’t touch , press or rub the eye during cleaning the eye or anytime to avoid damage to the
eye.
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Clean your eye with boiled and then cooled cotton on the inner and outer side of the eye and the eyelashes gently along the lid margins without any pressure on the eye.
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During daytime put dark glasses on and at night time put the green shield for 3 weeks.
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Don’t bend too much forward. Don’t carry heavy weight for 1 month. Avoid bending down to lift things; rather kneel down to pick up things. Similarly lift your feet to put shoes rather than bending down to wear them.
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