
Cataract development is part of the normal ageing process. Almost all people above the age of 60 years have cataract of a variable degree, although it can occur at an earlier age also. In some people cataract development is aggravated by an eye injury, presence of diabetes, use of medications or other eye diseases. Rarely cataract may be present in the newborn as a developmental defect.
Your eye surgeon will be the best judge to decide whether you can undergo microincision phaco-surgery. Each patient undergoing cataract surgery at our centre is examined in detail to assess the endothelial count of the cornea using the automated Specular Microscope. This facility at Kailash Eye Hospital & Laser Center is one of the very few available in the Capital. Based on findings of the endothelial count by specular microscopy it may be necessary to alter certain medication used at the time of surgery. If the endothelial cell count is low we are using BSS Plus and Viscoat, which are imported medicines, to minimize loss of the already depleted endothelial cell counts during surgery.
Monofocal IOLs
These lenses provide good distance vision and most patients are not dependent on their distance glasses for daily activities. However, patients implanted with monofocal IOLs typically require reading glasses after cataract surgery.
In the recent years, monofocal lenses have been designed with aspheric surfaces. These state-of-the-art FDA approved aspheric or aberration-free IOLs greatly improve image quality by enhancing contrast, eliminating glare and haloes, and improving night vision.
Toric IOLs
These special lenses correct high cylindrical powers reducing the patient’s dependence on distance glasses.
Multifocal IOLs and Accommodative IOLs
These lenses are designed to provide good unaided distance and near vision with less dependence on glasses.
IOL power calculations at Kailash Eye Hospital & Laser Center are done by trained personnel and every endeavor is made so as to get very minimal post-operative power in the distance glasses. This is done using immersion ultrasound biometry for measuring the eye accurately before the operation. A new device called the IOLMaster is available at the centre which is capable of extremely accurate measurement of the eye and calculation of the IOL power.
Once the IOL is implanted in the eye, it remains in place for the remainder of one’s lifetime.
Fortunately, the technological advances in IOL manufacture and surgery have made it quite safe. Complications are rare and similar ones can occur with conventional surgery without an IOL implantation. All patients irrespective of other general illnesses like diabetes, hypertension etc. can have IOL surgery. If there is any reason why you should not have an IOL your ophthalmologist will explain.
Until a few years ago cataract could not be removed with lasers. Surgery done by phacoemulsification was commonly termed “Laser Surgery” by lay people. Now, some of the steps of cataract surgery can be performed by Femtosecond Laser which has significantly improved the precision of some of the most critical steps that were traditionally performed manually. The femtosecond laser is a special laser which allows the surgeon to create high precision incisions. The femtosecond laser technology has already been in use in the recent years for creating precise flaps in bladeless LASIK with more predictable outcomes and increased safety.
More recently, the femtosecond laser is being utilized to assist or replace several aspects of the manual cataract surgery. These include the creation of the surgical incisions in the cornea, circular opening on the lens surface (capsulotomy), and breaking up (fragmentation) of the lens. The femtosecond laser can also be used to make incisions in the peripheral cornea to aid the correction of pre-existing astigmatism (cylindrical power).
In conventional phacoemulsification surgery, the surgeon makes the corneal incisions with a metallic blade, and manually creates an opening in the front of the lens capsule to gain access to the cataract, and then divides the cataract with a hand held ultrasonic probe.
In bladeless cataract surgery, the Femtosecond laser is used for these three critical steps of cataract surgery, i.e. to make the incisions, the opening in the lens capsule, and to divide the lens into fragments. Thereafter, the lens fragments are removed by the surgeon using the ultrasonic probe.
In both traditional cataract surgery and bladeless laser cataract surgery, microsurgical instruments are used in the operating room to remove the cloudy lens from the eye. The back membrane of the lens (called the posterior capsule) is left in place. An intraocular lens is placed inside the eye to replace the natural lens that was removed.
As the entire laser process is carried out under computer-guided OCT imaging, there is greater control and reliability of the incisions with regard to size, shape and location. It also allows perfectly-shaped, perfectly-sized and precisely centered capsule opening to be made into the cataract lens which does not depend upon the surgeon’s skill or experience. This enables accurate positioning and insertion of the artificial lens implant which optimises the visual outcome. This is of utmost importance in premium intraocular lenses such as aspheric design IOLs, Toric IOLs, Multifocal IOLs and Accommodative IOLs where the slightest error can compromise the quality of vision. Moreover, as the laser divides the lens into small fragments, the amount of ultrasound energy used to remove the cataract is greatly reduced, which in turn helps in early visual recovery.
What is a “Cataract Refractive Suite” and what additional benefits does it offer over only femtosecond laser assisted cataract surgery?
The VERIONTM Image Guided System captures a high resolution image of the patient’s eye which is transferred to the operating microscope. This image is superimposed on the surgeons view. It thereby provides automated incision positioning, guidance for making the opening in the lens capsule, as well as centration and alignment guidance for multifocal and toric IOLs.
The LenSx® Femtosecond Laser System performs the laser assisted steps of cataract surgery and includes corneal incision(s), lens capsule opening (capsulotomy), and lens fragmentation as previously described. The precision and accuracy of these steps of cataract surgery has now been further improved upon by the VERION Image Guided System. The image of the patient’s eye captured by the VERION can be directly fed into the LenSx Femtosecond laser to bring about a significant level of precision, accuracy and predictability to bladeless laser assisted cataract surgery.
The LuxORTM LX3 operating microscope is a top-of-the-line surgical microscope with superior illumination and depth of focus. It allows the surgeon to safely and efficiently perform all steps of cataract surgery with great ease and comfort. It allows the patients eye image as captured by the VERION to be superimposed in the surgeons view, thereby guiding incision creation, capsulotomy and precise alignment of Toric IOLs and perfect centration of Multifocal IOLs.
The Centurion® Vision System for phacoemulsification is a state-of-the-art machine for performing microincision cataract surgery. It has a unique mechanism called “Active FluidicsTM” technology which detects and instantaneously responds to changes in intraocular pressure (eye pressure) during surgery. This system provides unparalled safety by creating a stable environment with a consistent eye pressure throughout cataract surgery.
Combining all these technologies provides multiple benefits to the patient. It translates to safer and more precise surgery, early visual recovery and less chances of dependence on glasses.
No surgeon in the world can perform a surgery with guaranteed results. However, almost all the patients regain good vision following cataract surgery. In certain cases, eye disease or problems in the cornea, retina or optic nerve may limit the potential for clear vision even when the cataract surgery itself has been successful. However, it might not be possible to evaluate the condition of the retina, optic nerve, in advanced cataracts.
Modern microsurgical techniques for cataract removal are highly successful procedures. The few complications that exist are becoming even more remote, with newer developments in surgical techniques and anesthesia.
Some minor complications that can occur include a slight drooping of the eyelid, swelling around the eye, corneal haze, reflections or slight distortion from the lens implant, which are usually temporary. The chances for serious complications are negligible. Possible serious complications include infection, severe inflammation, and hemorrhage.
In a majority of cases these complications can be treated successfully or may resolve on their own with a good final restoration of vision. The above list is however not exhaustive.
However, in a certain number of patients undergoing cataract surgery, the back part of the lens capsule may thicken over a period of time causing blurred vision. This is known as Posterior Capsular Opacification (PCO), secondary cataract or “After Cataract”. This is not a complication. The condition is treated with a “YAG Laser Capsulotomy” with full restoration of vision
There are numerous benefits of cataract surgery, many of which cannot be measured statistically. These include:–
Improved colour vision – colours are brighter and more vivid
Greater clarity of vision – vision is crisper and sharper
Improved quality of life – studies have repeatedly shown that people enjoy an improved quality of life after successful cataract surgery. Many people can resume driving, reading, writing, watching television, sewing, household work and using a computer immediately after.
Even when retinal diseases or other problems prevent a total restoration of vision, the remaining vision is usually improved by cataract surgery.
Damage due to glaucoma is preventable, not curable. It is therefore necessary that the disease should be detected and treated at its earliest stage to prevent blindness.
• Frequent change of reading glasses.
• Mild eye ache or headache towards the evening after a day’s work.
• Seeing rainbow colored haloes of light around a bulb associated with slight decrease in vision.
• Inability to adjust one’s vision on entering a dark room. ” Difficulty in focusing on close work.
• In advanced cases, there is a loss of side vision, while the central vision remains good. The patient becomes more prone to accidents as he/she is unable to see vehicles coming from the sides.
• It is to be remembered, that cataract (“Safed Motia”) also starts developing at the same age as glaucoma. Many people may think that they are losing vision due to cataract whereas it may actually be due to glaucoma, which is a much more dangerous disease.
• It is therefore advisable to undergo a routine examination around the age of 40 years to screen for glaucoma.
• Presence of glaucoma in other family members • Increasing age – above 40 years • Thyroid disease o Patients who are on long term steroid therapy for other diseases such as asthma, arthritis etc. • Previous eye injury or surgery o Hypermetropia (farsightedness) Damage due to glaucoma may be more severe in those patients who have associated diabetes, widely fluctuating blood pressure and myopia.
There are three main varieties of glaucoma in adults which concern us:- • Chronic Glaucoma or Open-angle Glaucoma • Acute Glaucoma or Closed-angle Glaucoma • Secondary glaucoma, which develops due to systemic diseases like prolonged diabetes, complicated high blood pressure, thyroid disease, bleeding disorders etc. It may also occur as a complication of associated eye disorders such as vascular blocks, bleeding inside the eye, uveitis, swollen lens, blunt injury to the eye, etc.
Let us explain with the simple example of a kitchen sink at your home. There is a tap through which water comes and there is a drain through which water, after cleaning utensils, is drained off. If the drain is blocked, water accumulates in the sink. Similarly, in your eye, there is an area which produces a clear fluid which circulates inside the eye and provides oxygen and nourishment to the vital parts. Likewise, there is a small drainage channel through which all the waste products from inside the eye are drained. In glaucoma, this passage or the drainage channel is blocked, either at its entrance or beyond. When the block is at the entrance it is called Closed Angle Glaucoma. When the blockage is not at the entrance, but beyond, somewhere inside, we call it Open Angle Glaucoma. The blockage results in more fluid accumulating inside the eye that can be drained out. This leads to a buildup of high pressure inside the eye.
• After the age of 40 years, one should get an eye check up for glaucoma every 3 to 4 years even if there are no symptoms. • If a family member has glaucoma, if you have diabetes, if you are on long term systemic steroids for some other disease, or if you have suffered a blunt eye injury in the past, you must get your eyes checked every 1 to 2 years.
RGP (Semi-soft) lenses: RGP lenses are made of special, firm plastics combined with other materials, such as silicone and fluoropolymers, which allow oxygen in the air to pass directly through the lens. These lenses are very durable and typically last longer than soft lenses. RGP lenses provide excellent quality of vision, have a long life, and can correct astigmatism as well as uneven curvature of the cornea. The disadvantages are that these may take a little longer to get used to, it is easier for dust to get behind RGP lenses, causing irritation and discomfort, and one can’t switch back and forth with glasses as easily. However, regular wearers find them comfortable and the visual acuity outstanding. Soft lenses are made of flexible water-absorbent (hydrophilic) material having water content between 30-80%. These lenses are comfortable the moment they are inserted in the eye. They are less likely to dislodge and can be worn for longer periods. However, their biggest disadvantage is that they cannot correct higher degrees of astigmatism. They also need to be changed more frequently.
Each individual is different, although there are some broad guidelines that may be followed. If you are interested in initial comfort, soft contact lenses may suit you better than rigid gas permeable (RGP) lenses. On the other hand, RGP lenses tend to last longer. A soft (hydrophilic) lens is more appropriate for occasional wear (at most once or twice a week).
Not everyone can wear both types. Only after thoroughly examining your eyes and vision, can one advise whether you can wear RGP lenses, soft lenses or both. In your initial consultation, a number of tests and measurements will be performed, usually following a full, general visual examination. This evaluation will determine the optimum contact lenses for your specific needs. Additionally any other factors that determine your ability to wear lenses successfully will be explained to you.
Various general health factors, including medication, ocular, medical and family history will be assessed. A number of prescription medications, drugs and allergic factors can influence the ability to wear contact lenses successfully. Additionally your work and social environments can affect lens choice for example air-conditioning, computer use, dusty environments and so forth will affect the lens choice.
No, the two weeks refers to the actual amount of wearing time so they can last longer than two weeks if you are not wearing them full time.
Most first time wearers are delighted with the level of comfort that contact lenses provide. Initial contact lens fittings by professional eye care practitioners can minimize or eliminate any irritation associated with new lenses. After a brief adjustment period, most people report they can no longer feel contact lenses on their eyes.
With normal use, contact lenses will stay firmly in position. However, they can come out under certain conditions. High winds can cause the eyes to water and pull the eyelid tight against the eye, increasing the chance of lens loss. A sharp blow to the head may dislodge rigid gas permeable lenses. And rubbing your eye carelessly may result in a lost lens.
Describe to your eye care practitioner all of the circumstances in which you are likely to wear your contact lenses. This will help him or her prescribe a type of lens that is less likely to be dislodged given your activities.Your eyes and your vision are precious, and good contact lens care can help assure a lifetime of healthy eyes. It’s important to follow the instructions for daily or weekly lens care prescribed by your eye care professional for your type of lenses. The basic steps include cleaning, rinsing, and disinfecting (for storing). Cleaning solutions remove dirt, protein, oils, mucus, and debris that get on the lens during wear. Disinfecting solutions kill bacteria and other germs on the lenses. Disinfection is necessary to help prevent serious eye infections. Rinsing solutions remove other solutions from the lenses. They also prepare the lenses for wear. Enzyme solutions remove protein and other deposits that accumulate on the lenses over time. Rewetting solutions are used to wet (lubricate) the lenses while you are wearing them, to make them more comfortable. These steps can be performed using separate solutions. However, recently, there has been a strong movement to “one-bottle” systems. These all-in-one solutions are the easiest and quickest to use. You should not make your own lens care solutions, nor should you mix different brands of solutions unless instructed by your eye care practitioner. However, if you are particularly sensitive to chemicals, it may be better to use a hydrogen peroxide system. One must remember that all contact lens cases need frequent cleaning, including disposable lens cases. As a rule never bring any contact lenses in contact with tap water as it can be source if serious (sight-threatening) eye infection.
The need to use protein remover tablets depends on the amount of protein deposits your eyes produce and how often you replace your lenses. Protein deposits are normal. But as they age, they can change in chemical composition, contributing to discomfort and poor vision or leading to allergies. Regardless of your lens replacement schedule, however, daily cleaning is important for eye health. Consult your eye care practitioner for the best advice regarding your replacement and cleaning schedules.
Weekly enzyme cleaning helps keep soft lenses free from deposits of protein naturally produced in your eyes and carried by your tears. Lately, solutions are available, which eliminate the need for enzyme cleaning as well. Soft extended-wear contacts are the most likely to have protein build-up and cause lens-related allergies. Soft daily-wear lenses are less likely to create problems. Rigid gas-permeable lenses may be good choices for someone with allergies, as less protein is deposited on the lenses. If these deposits become a problem, your eye care practitioner may recommend a type of contact lens that you replace more frequently. Depending on the replacement frequency, using a protein remover in addition to your daily cleaning regimen may not be necessary.
The type of care contact lenses require, and how long they should be worn, is something each eye care professional will prescribe for each patient. Personal wear and care regimens may depend upon the type of contact prescribed, the nature of the vision problem being corrected, and the individual’s unique eye chemistry. Regardless of the type of lens you wear, you will find that lens care is now easier and more convenient than ever before.
Wearing contact lenses for sports is a more flexible and stable form of eye correction than eyeglasses, and athletes of all kinds have discovered the advantages of wearing contact lenses when participating in sports or working out. Contacts don’t steam up from perspiration, don’t smudge and don’t get foggy if you go from cold to warm temperatures. They provide better depth perception and complete peripheral vision. Today’s close-fitting contacts stay on your eyes, even during vigorous activity. If your sport involves vigorous exercise, a soft contact lens is an appropriate choice. Your eye care practitioner can help determine the best type of lenses based on your sport or activity.
Pool water can cause discomfort due to chlorine. It is best to avoid swimming with your contact lenses on because it exposes your contacts to bacteria and other microorganisms in the water. These can adhere to your lenses and place you at risk of eye infections.
If you do swim with your lenses, you should wear goggles with a firm seal. If you don’t wear goggles, the contact lenses may float from your eyes. They may also absorb the pool water, one consequence of which may be that they adhere quite firmly to the eye. If this occurs, it is advisable to leave the lenses alone for 10-15 minutes until your natural tears have replaced the water in them, before trying to remove them. You should then disinfect them immediately afterwards.
Laser Photocoagulation Laser for long has been the mainstay of treatment for many retina disorders as Diabetic Retinopathy, Vascular Occlusion, Age Related Macular Degeneration, Vascular Malformations and as a prophylaxis treatment for Retina Tears and Lattice Degenerations. Photo Dynamic Therapy a newer modality for treatment of age related macular degeneration and is very useful for specific indications. It is a safe modality in cases where therapy is needed close to the fine vision area of the retina. Laser is often a preventive modality that enables our patients to preserve their vison, enabling them to see a better tomorrow. Intravitreal Injections Oedema or swelling at the macula (The central fine vision area of the retina) known as Macular Oedema can be well treated with Anti-VEGF injections of Lucentis, Avastin and Triamcinolone Acetate. For years our patients have and are being treated with these injections at regular intervals with improvement in vision and decrease in oedema. AntiVEGF injections also play a very important role in the treatment of wet AMD and have been used at our centre for years with appreciable and significant treatment results . OZURDEX A novel intravitreal drug delivery system has been developed that gradually releases the steroid dexamethasone after it has been inserted into the eye through a small puncture. It is composed of biodegradable copolymers. As dexamethasone is released, the polymer slowly degrades into carbon dioxide and water. Since the implant eventually dissolves completely, sequential implants can be placed into the eye over time without the need for surgical removal. It has shown great benefit in treatment of macular oedema due to retinal vein occlusions.
VASCULAR OCCLUSIONS Occlusions of the retinal vascular system is the second most common retinal vascular disorder after diabetic retinopathy. They occur due to a blockage of the blood vessels which serve the retina. SYMPTOMS Painless loss of vision Diagnosis is generally clinical They can be of 2 Types Venous occlusions Arterial occlusions Venous Occlusions are the more common of the two and has a better prognosis. The drop in vision in this disorder is generally due to thickening of the central part of the retina called the macula which is the area for fine vision OCT is a useful non invasive diagnostic modality for diagnosing edema or swelling due to vascular occlusions. Fluorescein Angioigraphy is also performed to get to know about blood supply and to determine any risk of future bleeds in these eyes. Recently intravitreal injections of anti VEGF agents and steroid injections/implants have shown good results in treating macular edema associated with venous occlusions. These may need to be repaeted frequently depending on the patients response to therapy. Arterial occlusions are less common and are often associated with sever permanent vision loss. Systemic factors like hypertension, cardiac history, high cholesterol and Diabetes are known to be associated with vascular occlusions. Your ophthalmologist may refer you to a physician or cardiologist in such cases.