FAQ: Cornea

What is Cornea?

Clear front part (watch-glass) of the eye.

The cornea is the normally clear, front window of the eye that covers the colored iris and round, dark pupil. Light is focused while passing through the cornea, allowing us to see.

What is the function of cornea?

A healthy, clear cornea is necessary for good vision. It is the first layer through which light is focused into the eye.

How can cornea be affected?

If cornea is injured or affected by disease, it may become swollen or scarred, and its smoothness and clarity may be lost. Scars, swelling or an irregular shape can cause the cornea to scatter or distort light, resulting in glare or blurry vision.

What is Corneal Ulcer?

Any injury, infection or foreign body in the cornea can cause ulcer or infection of the cornea which can cause severe pain, redness, whiteness on the cornea and loss of vision.

How is corneal ulcer treated?

Treatment of corneal ulcer involves intensive and appropriate anti-microbial therapy (determined after microbiological testing of corneal scrapings). If medical management fails, surgery may have to be done. If a corneal transplant is necessary, the damaged or unhealthy cornea tissue is removed and clear donor cornea tissue is put in its place.

What are the other conditions for which a corneal transplant is done?

There are many conditions that can affect the clarity / functioning of the cornea, and require a corneal transplant.

They can be:

  • Congenital: Related to shape (Keratoconus) and size (Micro cornea / Megalocornea)
  • Hereditary: Fuchs’ dystrophy
  • Acquired: Due to trauma / injury / infections / complicated cataract surgery
  • A corneal transplant is needed if vision cannot be corrected satisfactorily with eyeglasses or contact lenses, or if painful swelling cannot be relieved by medications or special contact lenses.
  • A corneal transplant is done using a human donor cornea. Before a cornea is released for transplant, tests are done for viruses that cause hepatitis, AIDS and other potentially infectious diseases. The cornea is also checked for clarity.

What are the types of corneal transplant?

Corneal transplant (Keratoplasty) can be:

1. Full thickness corneal transplant surgery (known as penetrating keratoplasty): A circular portion is removed from the center of the diseased cornea. A matching circular area is removed from the center of a healthy, clear donor cornea, placed into position and sutured into place.

2. Lamellar Keratoplasty:
a. DALK: Deep Anterior Lamellar Keratoplasty (only front layers transplanted)
b. DSAEK: Endothelial keratoplasty (only abnormal inner lining of the cornea is replaced)

Opaque cornea due to infection   Clear cornea after corneal transplant

What is Eye donation?

Eye donation is the donation of cornea after death which is then transplanted to corneally blind people.

Who can donate eyes?

Anyone can be an Eye Donor

  • People of any age
  • Spectacle users
  • Eye surgery patients
  • Diabetics, Hypertensive

How much time does it take for removal of eyes?

Removal of eyes takes only 20 minutes. It does not delay funeral arrangements or disfigure the face.

What is the time gap for removal of eyes after death?

Eyes can be removed within 6-8 hours of time of death. If eyes are kept moist with wet cotton and in an air-conditioned room, a longer gap also may be acceptable.

Can eyes be donated only if the deceased has pledged his / her eyes?

No. Eyes can be donated irrespective of whether the deceased had pledged his/her eyes or not. Decision is taken by the next of kin.

We at Sadguru Netra Chikitsalaya are striving towards eradication of corneal blindness through MK International Eye Bank in Indore (M.P). We have a 24-hour dedicated helpline. The Eye Bank Staff attend to eye donation calls 24 x 7 on all 365 days. We also conduct lot of awareness programmes and screening camps for the same.


Am I a candidate for LASIK?

The decision to have laser vision correction depends on the results of a thorough preoperative evaluation. Just as you are a unique individual, each eye requires unique and careful examination with the best technology. At Sadguru Netra Chikitsalaya, we complete a 2 1/2 hour, 27 point evaluation to determine whether or not you are a safe candidate for laser vision correction. It is important to understand that not everyone is a suitable candidate for LASIK. Some basic requirements include:

  • A stable eyeglass prescription for at least two years.
  • Best corrected vision of at least 20/40.
  • Healthy cornea.
  • No active eye disease.
  • Over 18 years old.

How safe is LASIK?

The FDA has approved LASIK as a safe and effective procedure. It is important, however, to remember that LASIK is not the right choice for everybody. Some people are not appropriate candidates, and if treated could have less than optimal results. It is important that you receive a thorough pre-operative evaluation to determine if LASIK is right for you.

Does LASIK hurt?

No. The actual treatment itself is painless. You will be given plenty of anesthetic drops to completely numb the eye. You may feel a light pressure sensation around your eye, and after the procedure is finished you will feel a sensation our patients describe as gritty or like a lash in your eye for a few hours... but most people experience very little pain. We’ll give you a prescription for a pain reliever should you need it, but most people need nothing more than Tylenol or Advil and a little rest time.

How long does it take to do LASIK?

The actual procedure usually takes less than 10 minutes per eye. Depending on your prescription, and the amount of correction needed, the laser itself only takes 20-50 seconds to correct your vision. However, you should plan on being in the office for approximately an hour-and-a-half on your day of surgery.

How accurate is LASIK?

LASIK is very accurate. Careful consideration of your needs and a complete preoperative evaluation help Sadguru Netra Chikitsalaya achieve excellent results with the vast majority of our patients. Even with our advanced technology and experience, approximately 1 in 10 patients may need to have a retreatment in one eye to achieve their best uncorrected vision. This is because we are treating human tissue and there is always some variability in how each individual’s eye will heal.

What if I blink or move during the procedure?

Although everyone shares these concerns, we take measures to ensure that moving or blinking is not a problem. Your eye will be held open with a holder supporting your lid so that you can’t blink. The holder is placed immediately before the treatment and removed immediately afterward. Lying still during the treatment is another common concern. The bed of the laser has a contoured headrest with an indent, which allows the back of your head to rest securely, but comfortably in place.

How soon after the surgery will I be able to see?

Visual recovery varies from one day to one week. The majority of patients resume normal activities one to two days following surgery but it may take 1 to 2 months for your vision to fully stabilize. Although everyone is a little different, the vast majority of our LASIK patients achieve legal driving vision or better, the very next day. That is one of the most exciting advantages of the LASIK procedure; clear vision comes in quickly. Initially, your vision might not be crisp and may fluctuate slightly. This is perfectly normal and should improve gradually day by day.

When will I be able to drive?

On the day of your surgery it is important to have a driver take you home. You will also need a driver to bring you to your post-operative appointment the day after surgery. In most cases, patients are able to drive by the end of that day.

What are the possible complications?

It’s perfectly normal to be concerned about the “worst case scenario”. We, at Sadguru Netra Chikitsalaya have never had a patient experience severe vision loss as a result of refractive surgery. With an experienced surgeon, the procedure itself is relatively safe. Statistically, there is a remote possibility of the loss of vision due to corneal infection or inflammation which we address by maintaining sterile conditions in the laser suite and by instructing you to use medicated drops for the first week after the procedure. Fortunately, we have never had a patient lose vision from these problems.

I’ve heard that the laser causes night vision problems…is this true?

Starbursts, glare and halos at night can be caused by several things. The first is when an inadequate diameter area of the cornea is treated. The treated area must approximate your pupil size under dim light. We analyze pupil size four different ways to make certain that your treatment area is large enough. The second cause of night vision problems is the use of older generation lasers and poor treatment designs. The third potential cause of night vision problems after LASIK is the presence of subtle optical imperfections known as Higher Order Aberrations in the visual system. But, this treatment pattern reduces the incidence of star bursting. Very few of our patients report any night vision problems after their first month post-op.

How long will the effect of LASIK last?

In most cases, the treatment effect of laser vision correction is permanent, especially if your eyeglass prescription was stable before treatment. If there is something in your genetics that says your prescription will change in the future, having surgery now will not prevent that from occurring. In our experience, a change like this is very uncommon If necessary though, you may be able to be re-treated many years later should that occur.

FAQ: ICL Surgery

Will I be able to feel the ICL in my eye?

No you will not be able to feel the new lens. The lens sits snugly behind your pupil and does not move.

Will I be able to see the lens in my eye?

The lens is crystal clear and sits behind the pupil. You will not be able to see the lens from the outside.

How quick is the recovery period?

Visual recovery is very rapid but depends on the type of local anesthetic that you are given. You may feel a slight gritty sensation of the eye for a day or two after surgery, almost like an eyelash in the eye. This usually settles very quickly.

Will I need drops after surgery?

You will be given a combination of antibiotic and steroid eye drops to put into the eye for a few weeks after the surgery.

Can anyone have ICL surgery?

Eligibility for ICL surgery is dependent on your prescription and the anatomy of your eye. The front part of the eye has to be at least 3mm deep for safe insertion of the lens. Your glasses prescription should also have been stable for at least 2 years. 

What happens if my prescription changes years after I have ICL surgery?

If your prescription changes it will typically be only a moderate change and it is easy to treat this with laser eye surgery at any time.

How is the power of the ICL determined?

The lens power is determined by a number of measurements including your glasses prescription.

One of the most crucial measurements is the size of the lens that needs to fit into your eye. This varies between people and is dependent on individual anatomy. Occasionally, the sizing of the lens is inaccurate which means that the lens is either too small or too big for the eye. This is not something that you'll notice but is something your doctor will be able to tell. Around one in a hundred patients sometimes have to have their lens removed and a different sized lens reinserted.

Is ICL surgery safe?

ICL surgery is safe and effective. Hundreds of thousands of these lenses have been implanted over the last 15 years. The lens material, made of collagen a substance that occurs naturally, is well tolerated and remains clear.

What complications can occur with ICL’s?

ICL surgery is safe but like all surgery complications can rarely happen. Occasional complications include cataract formation and an increase in the pressure within the eyes.

More serious complications such as an infection within the eye that can lead to permanent reduction in vision are very rare and occur in less than 1 in a 1000 (0.001%) patients. Risk of blindness is around 1 in 10,000 (0.0001%).

FAQ: Keratoplasty/Corneal Transplantation

What is the cornea?

The cornea is the eye’s outermost layer. It is the clear, dome-shaped surface that covers the front of the eye.

What is corneal blindness?

When the cornea becomes cloudy, light cannot penetrate the eye to reach the light-sensitive retina. Poor vision or blindness may result.

What is a corneal transplant?

A corneal transplant involves replacing a diseased or scarred cornea with a new one.

Is the whole eye transplanted?

No – only the corneas can be transplanted. The entire eye may be used for research and education.

How prevalent is corneal transplantation?

There were 46,196 corneal transplants performed in the U.S. in 2011. Since 1961, more than 1,000,000 men, women, and children ranging in age from nine days to 100+ years, have had their sight restored.

How successful is corneal transplantation?

Over 95 percent of all corneal transplant operations successfully restore the corneal recipient’s vision.

Why should eyes be donated?

There is no substitute for human tissue. The transplantation process depends upon the priceless gift of corneal donation from one human to another. Donated eyes are also needed for research and education.

Who can be a donor?

Anyone can. The great thing about corneal tissue is that everyone is a universal donor. Your blood type does not have to match. It doesn’t matter how old you are, what color your eyes are or how good your eyesight is. Aside from those suffering from infections or a few highly communicable diseases such as HIV or hepatitis, most people are suitable donors.

Will the quality of medical treatment be affected if one is a known donor?

No. Strict laws are in existence, which protect the potential donor. Legal guidelines must be followed before death can be certified. The physician certifying a patient’s death is not involved with the eye procurement or with the transplant.


What are the criteria for doing C3R?

In progressive Keratoconus in order to strengthen the cornea C3R is recommended. The minimum corneal thickness required is 400microns and above.

What is the duration of C3R treatment?

The duration required is roughly 60 minutes. 30 mins for riboflavin application and 30 mins for the UV light exposure.

Is the procedure painful?

C3R is done under topical Anesthesia. The post procedural pain may persist for 2 to 7 days.

Does C3R causes blurring of vision?

The blurring will persists for couple of days to 10 days.

Does C3R stabilize the vision in Keratoconus?

The main purpose of doing C3R is to stabilize Keratoconus so that contact lenses or glasses can be used to have clear vision.

Whether C3R give immediate results?

No. To know the effect of C3R we have to wait for minimum 3 to 6 months.

When do I start working after this treatment?

After 2 to 3 days usually people who undergo C3R will be comfortable to work.