What kind of laser does the doctor use?

The laser we use is the ZEISS LASIK Laser

What do you mean by the “flap”?

What makes LASIK pain-free and what was invented 20 years ago is the ‘LASIK flap’. It is created before the laser removes the numbers. The thickness of the flap to be taken is determined during your evaluation process. We work best with the Moria M2 microkeratome, a completely automated and very safe device for creating the flap.

What is the corneal-saving advantage of LASIK on the Zeiss Laser ?

The US FDA gives a baseline of 250 microns cornea to be left behind after the laser treatment. Our centre believes in leaving at least 300 microns. Your calculation will be done during evaluation. It should leave at least 300 microns behind on the cornea after the laser treatment is completed.

The cornea is like the door to your eye and the stronger or thicker the door, the better it is for you. The Zeiss Laser which we use has its advantages in this respect of corneal saving as this laser saves up to 40% of the cornea compared to other lasers. In simple terms it means that another laser would remove far more corneal tissue to remove the same number. Also, when creating a 90 micron flap, which we do using single use heads, it leaves even more cornea after the procedure. This great advantage for people with high numbers or people which other laser centres cannot treat.

What if you have an electric cut out during my laser or my treatment is disrupted for any reason?

We work on the uninterrupted power supply system or UPS with the laser. NEVER run the laser without it. Hence, there is no interruption in the surgical procedure even in case of power cut from the external source.

How do I find out which laser system is good?

The laser systems should possess specific features for higher quality visual results.

The Zeiss company (Our laser company ) has most advanced topoguided lasik treatment.

• Laser Spot Size

  The small laser spot size is mandatory to produce fine complex treatment patterns. Smaller the size, finer the treatment. Ours is the smallest in the world so far… viz 0.68 HM

• Speed

  Shortens ablation/ treatment time remarkably. To the benefit of the surgeon and to the comfort of the patient, Because shortened corneal exposure time allows faster visual recovery.

  The rapid rate is vital to maintain corneal hydration intra-operatively, especially in wavefront guided procedures with larger optical zones where a prolonged treatment time could adversely affect the planned treatment profile. A simple principle in laser refractive surgery is to keep the eye as physiologically hydrated as possible intra-operatively for a faster visual recovery.

  Hence, faster speed lasers have better visual outcomes. Our is the fastest in the world so far viz keeping in mind the safety limit as well.

• Optical Zone

  Ideally the laser should have the widest treatment area that also removes the least tissue possible, which is what our laser supports. Most Other lasers in order to treat a wider area take out more corneal tissue. This also results in night vision problems. In the night the pupil expands or dilates to let in more light for visibility. If a laser treats a zone, which is smaller in diameter than the diameter of expansion of the pupil, then what you have is an untreated rim of cornea, which in the night is going to result in haloes or glares of light. Most lasers treat upto a 5 mm zone to 6 mm only, ours can treat upto 7 mm. In cases of patients with night glare due to earlier treatments, the ability of our laser to retreat is highly beneficial.

• Eye Tracking speed

  The eye is kept fixed with the laser during treatment. However there are fine saccadic eye movements not seen by naked eye. The Zeiss Laser is better than any other excimer laser system as it tracks the eye at 500 times a second and allows for spot on treatments. Most other lasers have an eye tracker which if the eye moves even to some extent during treatment, then the laser stops.

• Topography Link treatment

  Is necessary for a customized laser treatment. Especially in re treatments when undergone earlier LASIK and patient is unhappy.

  For topography-linked retreatment’s, the Zeiss Laser has the best capabilities at present.

I understand Zeiss LASIK is what is being carried out recently by taking a 3D map of the eyes in order to customise the treatment to each person. I believe this is best for better night vision and the absence of glare and halo effects. A friend of mine had glare and not so great night vision. Have any of your patients had any issues with night vision and glare?

Zeiss LASIK or custom LASIK is the most advanced LASIK method today. But it can be performed using various lasers. The speed of the laser and its application are very important in delivering results. Today, we use one of world’s fastest lasers.

That is why Zeiss laser gives near-zero night vision problems like glare and haloes, which may still occur with other systems. We also check your pupil size to ensure a more customized treatment zone. We have rarely recorded night vision problems, one of the reasons why many of our patients are from neighbouring states as well.

What is a cataract?

A cataract is a cloudiness of the eye's natural lens, which lies between the front and back areas of the eye, directly behind the pupil.

Are cataracts found only in older people?

Most cataracts develop slowly over time and affect people over age 50. In Indian population by age 55, and nearly everyone over age 75 has at least a mild cataract in one or both eyes.

In rare cases, infants can have congenital cataracts. These usually are related to the mother having German measles, chickenpox, or another infectious disease during pregnancy; but sometimes they are inherited.

My doctor says I have a cataract, but he wants to wait a while before removing it. Why?

Mild cataracts often cause little or no vision problems. Your doctor is probably monitoring your cataract to see if it worsens and more significantly affects your vision or lifestyle before recommending surgery.

Some cataracts never reach the stage where they need to be removed. But if your cataract worsens and you begin to have trouble seeing clearly for driving and other everyday tasks, it's probably time to consider cataract surgery.

Is cataract surgery serious?

All surgery involves some risk, so yes, it is serious. However, cataract surgery is the most commonly performed type of surgery in the World. Many cataract surgeons have several thousand procedures under their belt. Choosing a surgeon with this much experience will reduce the risk of something going wrong.

How is a cataract removed?

A small incision is made in the front surface of the eye with a scalpel or a laser. A circular hole is then cut in the front of the thin membrane (anterior capsule) that encloses the eye's natural lens. Typically the lens is then broken into smaller pieces with a laser or an ultrasonic device so it can be more easily removed from the eye.

Once the entire lens is removed, it is replaced with a clear implant called an intraocular lens (IOL) to restore vision. In most cases, the eye heals quickly after surgery without stitches.

Today, several steps in cataract surgery can be performed with a computer-controlled laser instead of hand-held instruments. Learn more about laser cataract surgery.

What is a "secondary cataract"?

In a minority of cases (perhaps 20 to 30 percent), months or years after cataract surgery, the posterior portion of the lens capsule that is left inside the eye during surgery for safety reasons becomes hazy, causing vision to again become blurred.

This "secondary cataract" (also called posterior capsular opacification) usually can be easily treated with a less invasive follow-up procedure called a YAG laser capsulotomy. In most cases, this 15-minute procedure effectively restores clear vision.

My grandfather had cataract surgery years ago, and he had to wear thick glasses afterward. Is this still necessary?

Rarely does anyone have to wear thick, heavy eyeglasses after cataract surgery these days. Most modern cataract procedures replace your eye's natural lens with an intraocular lens (IOL) that often can correct your distance vision to 20/20 without glasses or contact lenses.

In fact, premium multifocal IOLs and accommodating IOLs can even eliminate your need for reading glasses after cataract surgery. During your pre-op exam, ask your cataract surgeon for more details about how to reduce your need for glasses after surgery.

How much does cataract surgery cost?

The cost of cataract surgery varies from one doctor to the next; it also depends on the type of procedure and intraocular lens you and your cataract surgeon decide is best for your needs.

Medicare and most health insurance plans will cover cataract surgery and ordinary intraocular lenses, but not the cost of premium IOLs, such as presbyopia-correcting IOLs that simultaneously correct vision at near, intermediate and distant ranges. These types of lenses can cost as much as 35000-50000 Rs. or more out-of-pocket for both eyes.

What are possible side effects of cataract surgery?

As with any surgery, pain, infection, swelling and bleeding are possible, but very few people experience serious cataract surgery complications. In most cases, complications or side effects from the procedure can be successfully managed with medication or a follow-up procedure.

To reduce your risk for problems after cataract surgery, be sure to follow the instructions your surgeon gives you and report any unusual symptoms immediately.

Is Corneal Swelling after Cataract Surgery normal?

Cornea is the front transparent part of the eye and allows light to enter the eye. Additionally it accounts for 2/3 of the focusing power of the eye. Any disease or swelling of cornea can cause corneal clouding and this can cause a drop in vision. A lot of patients with corneal swelling may also complain of pain and light sensitivity along with reduced vision. Corneal swelling can happen due to many reasons and in most cases it resolves by itself.

Reasons due to which patients may develop corneal swelling and cloudiness after cataract surgery

• Pre-existing weak corneal endothelium– In some conditions like Fuchs’s endothelial dystrophy, Healed viral keratitis, healed corneal injuries etc. corneal endothelium may be already weak. Some other eye diseases like glaucoma, uveitis etc. can also weaken the corneal endothelium. These eyes with weak corneas are prone to corneal swelling when they undergo cataract surgery. In most cases it resolves by itself. Very rarely corneal swelling does not resolve and this tends to happen if the pre-existing corneal damage had been extensive.
• Advanced Brown Cataracts– Surgery on hard advanced cataracts can be damaging for the cornea and can lead to corneal swelling after the cataract surgery. During phacoemulsification cataract surgery a lot of energy is utilized for emulsification of hard nucleus and this in turn can cause clouding of cornea. Therefore it is advantageous for the patients to plan their cataract surgery at the right stage and not wait for the cataract to mature.
• Difficult Cataract surgery- Some cataract surgeries are more challenging and require a lot of manipulation inside the eye during the cataract surgery. This happens in some conditions like complicated cataracts, previous retinal surgeries, and post injury cataracts with associated zonular weakness etc. Longer duration and excessive manipulation can cause cornea to sustain some amount of damage during the cataract surgery. This in turn causes corneal swelling and clouding after the cataract surgery. In most cases it settles down and in rare cases it may be permanent and require cornea transplantation.
• Toxic reaction- In rare cases the solutions and medicines which are used during the cataract surgery may cause toxicity and induce a reaction inside the eye. This reaction also called Toxic Anterior Segment Syndrome causes corneal swelling. In most cases this reaction and the corneal swelling subsides with proper treatment after the cataract surgery.

Rajan had come to us with complaints of hazy vision in his right eye. He had undergone cataract surgery in his right eye 10 years ago. His symptoms started with increased light sensitivity and watering and soon he also developed reduced vision in his right eye. By the time he presented to us his cornea had developed a diffuse clouding and swelling. We found that the intraocular lens which was inserted in his eye by his surgeon had moved from its place and was rubbing against the back of the cornea. This slowly damaged the cornea and caused corneal swelling. We replaced that lens with another lens and slowly the corneal swelling subsided.

I think it is important to understand that corneal clouding and swelling after cataract surgery can happen. It is not always normal to have corneal swelling after cataract surgery. It is a rare occurrence. In majority of cases corneal swelling settles down within a few weeks with just medical treatment. Very rarely surgical treatment like cornea transplantation is required. The good news is that cornea transplantation has become very advanced and with newer surgeries like DSEK and DMEK, we can just replace the diseased corneal endothelium and cure corneal swelling.

What symptoms should alert me to see a Retinal Specialist?

The most common symptoms of retinal disease experienced by our patients include floaters and flashes, peripheral shadows, sudden loss of vision, or blurry/distorted vision.

Will my eyes be dilated on every visit? And for how long?

Yes. In order to best evaluate your eyes, your pupils must dilate so the doctor can see the retina. They will stay dilated and vision may be blurred for approximately 2 hours and longer for some patients.

Can I drive after my retinal eye checkup?

No. For your safety, it is better to arrange for someone to drive you home or take public transport.

How long will my visit take?

It will take approximately 45-minutes to 1 ½ hours for a complete eye examination and for any diagnostic tests that are needed.

What is the difference between a vitreo- retinal surgeon and a general ophthalmologist?

A general ophthalmologist is a specialist who performs general eye care including refraction and minor surgery as well as cataract surgery. A retina specialist or surgeon is highly trained in the diagnosis, management, and treatment of retinal problems such as macular degeneration, diabetic retinopathy, macular holes, macular puckers and retinal detachments. A retina specialist trains for many years beyond medical school: not only for four more years to become a general ophthalmologist, but for two additional years in a “fellowship” program to learn the details of retinal surgery.

Squint is a misalignment of the eyes where the two eyes are pointed in different directions. Though it is a common condition which affects children, it may appear later in life.

Before attempting to understand squint, its effects, and how it is treated, it is important to understand the function of eye muscles and their role in maintaining eye alignment and binocular vision.

Eye Muscles

Eye movements are controlled by eye muscles, much like reins control a horse's head. There are six eye muscles attached to the outside of each eye, which control its movement. In each eye, two muscles move the eye to the right or left side; the other four muscles move the eye up or down, and control tilting movements. In order to line up and focus both eyes on a target, all eye muscles of each eye must be balanced and working together with the corresponding muscles of the opposite eye. When the eye muscles do not work together, then misalignment of the eyes or strabismus results.

Binocular Vision & Depth Perception

The eyes are designed to focus images clearly on the retina and then to relay that image to the brain. If both eyes are lined up on the same target, the visual portion of the brain can fuse the two pictures into a single 3-dimensional image. This creates binocular vision and depth perception, which helps the eyes work together to transmit one "picture" to the brain. When one eye turns as in strabismus, two different pictures are sent to the brain. In the young child, the brain learns to ignore the image of the misaligned eye and see only the image from the straight or better-seeing eye. The image of the worse eye is suppressed. This causes loss of depth perception. Adults who develop strabismus usually have double vision because their brain is already trained to receive images from both eyes and cannot ignore the image from the weaker or turned eye.

What Is Amblyopia (“Lazy Eye”)?

Normal alignment of both eyes during early childhood is necessary to allow good vision to develop in each eye. Abnormal alignment as in strabismus may cause reduced vision or amblyopia ("lazy eye"), which is not correctable by glasses or contact lenses. Amblyopia occurs in approximately one-half of children with strabismus. The brain will recognize the image of the better-seeing eye and ignore the image of the weaker or amblyopic eye. Amblyopia often can be reversed by patching the preferred or better-seeing eye in order to strengthen and improve the vision of the weaker one. If amblyopia is detected before the first few years of life, treatment is often successful. If adequate treatment is delayed until later, amblyopia or reduced vision generally becomes permanent. As a rule, the earlier amblyopia is treated, the better the visual result. Amblyopia (lazy eye) and strabismus are not the same condition. Strabismus is one of the causes of amblyopia. Other causes are anisometropia (highly different spectacle prescriptions in each eye), and obstruction of vision in an eye due to injury, cataract, lid droop, etc.

How is Strabismus Caused?

Strabismus is caused by misaligned eye muscles. However, the exact reason for the misalignment of the eyes leading to strabismus is not fully understood. Many factors can be responsible for strabismus. They include:

• Inappropriate development of the "fusion center" of the brain, problems with the "eye movement" centers of the brain, and injury to or disease of the eye muscles or nerves. This explains why children with cerebral palsy, Down's syndrome and hydrocephalus often have strabismus. Even a brain tumor may cause strabismus.
• Another factor is genetics, and it is known that strabismus may run in families. However, in many patients there are no relatives with the problem. The condition occurs equally in males and females.
• Associated eye conditions may also give rise to strabismus. In cases of cataract, injury or tumor within the eye, the eye may frequently turn in or out.

What are the Symptoms of Strabismus?

The primary symptom of strabismus is an eye that is not straight. The misalignment may be permanent and always noticeable (constant strabismus), or it may come and go, appearing normal at times and abnormal at others (intermittent strabismus). One eye may be directed straight ahead while the other eye is turned inward, outward, upward, or downward. In other cases, the turned eye may straighten at times, and the straight eye may turn (alternating strabismus). Sometimes a youngster will close one eye in bright sunlight. Faulty depth perception may be present. Some children turn or tilt their heads in a specific direction in order to use their eyes together. Up to the first 6 months of age, intermittent strabismus is a normal developmental milestone. After 6 months, it needs to be evaluated.

Detection and Diagnosis

A child should be examined by the family doctor, pediatrician, or an ophthalmologist during infancy and preschool in order to detect any potential eye problem, particularly if a relative has had strabismus or amblyopia. Even the most observant parent may not discover strabismus without a doctor's help. It is often difficult to determine the difference between eyes that appear to be crossed and true strabismus. Young children usually have a wide, flat nose and a redundant fold of skin at the inner eyelid that tends to hide the eye during side gaze and cause concern about strabismus. An ophthalmologist can readily distinguish this from true strabismus.

Why Is Early Detection Important?

It is never too early to have a child's eyes examined. Fortunately, an ophthalmologist can test even a newborn infant's eyes. In general, research suggests that the maximum "critical period" in humans for the development of binocular vision with resultant depth perception is from just after birth to 2 years of age. Any disruption of binocular vision in this period will therefore result in strabismus and/or amblyopia. If the eye examination is delayed until the child enters school, it may be too late to properly correct strabismus and amblyopia. Occasionally, a misaligned eye may be caused by a cataract or tumor within the eye, as mentioned earlier. It is important to know about such conditions as early as possible, so that both the underlying condition and resulting strabismus can be corrected. Parents often get the false impression that a child may "outgrow" the problem. Though fatigue or illness may worsen strabismus, children do not outgrow strabismus. Once a child has a suspected turning of an eye, an examination by an ophthalmologist is necessary to determine the cause and to begin treatment.

When is it too late to treat Strabismus or Lazy Eye?

It is often asked at what age should treatment no longer be attempted. The answer is, everyone deserves a chance. Age should not be a deterrent, though treatment under 6 years of age (especially before 2) is ideal and allows better results than later treatment. After age 6, age is not important. However, every attempt should be made to improve strabismus and lazy eye, even though treatment might not be as effective after the age of six, and definitely requires more work.

What Are the Goals of Treatment?

The goals of treatment are to preserve vision, straighten the eyes, and restore binocular vision. Treatment of strabismus depends upon the exact cause of the misaligned eyes. It can be directed towards unbalanced muscles, cataract removal or other conditions that are causing the eyes to turn. After a complete eye examination, including a detailed study of the inner parts of the eye, an ophthalmologist can recommend appropriate optical, medical or surgical therapy. Covering or patching the good eye to force use of the amblyopic eye may be necessary to ensure equal vision. Constant strabismus must be dealt with immediately if one wants to re-establish proper use of the eyes. Treatment for this condition needs to be early and aggressive. If the eye turn is constant and simple things like patching, glasses (bifocal, prismatic, etc) do not eliminate the eye turn, surgery needs to be considered. With intermittent strabismus, the eye does not turn in all the time, so the brain is probably receiving appropriate stimulation for the development of binocular vision. Children with intermittent eye turns should be handled with judicious patching, special glasses, and/or orthoptics (special eye excercises designed to encourage binocular vision). Surgery, if considered at all, should be a last resort. The two most common types of strabismus are esotropia, where an eye turns in and exotropia, where an eye turns out.

Loss of Vision Due to Amblyopia Is Preventable Treatment for strabismus is most effective when the child is young. It becomes more difficult to treat strabismus and establish binocularity as the child grows older, but cosmetic straightening of the eyes remains possible at any age. There is no known prevention for strabismus, but misaligned eyes can be straightened, and loss of sight from amblyopia is preventable if treatment is begun early.

In summary:

Children with strabismus do not outgrow the condition.

Treatment for strabismus may be non-surgical and include eye drops or glasses.

If surgical treatment is indicated, it is wise to align the eyes when the child is young in order to allow more normal use of the eyes together. Besides the conditions mentioned above in children, there are certain disorders in adults which are associated with strabismus.

These include:

• Thyroid disease
• After cataract surgery
• After retinal detachment surgery
• Myasthenia Gravis
• Paralysis of eye muscles due to Diabetes and Hypertension
• Orbital fracture