WebMD Live Chat Transcript: Laser Vision Correction (LASIK) with Andrew Caster, M.D., F.A.C.S.

Transcribed by WebMD Staff 

Moderator Welcome to WebMD Live. Our guest this afternoon is Andrew Caster, M.D., F.A.C.S., who will be discussing Laser Vision Correction (LASIK).

Moderator If you would like to ask Dr. Caster a question, we encourage you to do so. Simply type /ask and then your question.

Moderator Dr. Caster was selected by Visx as one of the "Top 50" laser eye surgeons in the United States in 1998.

Moderator Dr. Caster, welcome to the show.

events_moderator what is astigmatism, and how is it fixed with lasers?

Dr_Caster Astigmatism is an irregular curvature of the cornea.

Dr_Caster The cornea is shaped more like a football than a basketball. We correct this by evening out the shape so it's more round .. like the basketball.

Dr_Caster The laser corrects astigmatism by removing tissue from the surface of the cornea, thereby leaving the cornea with a slightly different shape.

Dr_Caster Correcting near sightedness involves removing tissue in a circular patter, more tissue in the center than on the edges.

Dr_Caster When we correct astigmatism, we remove more tissue in one axis than in the perpendicular axis.

Dr_Caster And, when we correct far sightedness, we remove more tissue on the edges than in the middle.

events_moderator what other common eye problems can be fixed with a laser?

Dr_Caster The LASIK procedure only corrects near sightedness, far sightedness or astigmatism.

Dr_Caster The LASIK procedure uses an excimer laser to reshape the cornea.

Dr_Caster In the LASIK variation, the correction is made to the deep tissues of the cornea and this is achieved by rolling back the top layers of the cornea.

Dr_Caster A related variation of this laser procedure is called PRK.

Dr_Caster In PRK, the laser is applied directly to the front surface of the cornea without peeling back any of the layers.

events_moderator How much can a prospective patient expect their vision to improve after treatment?

Dr_Caster We try to have each patient see 20/20 without any glasses afterwards. We achieve that about 80f the time.

Dr_Caster 97f the time, the patient will see well enough to pass their driver's test without glasses or contacts.

Dr_Caster Virtually everybody is made better by the procedure, it's just that it's not 100ccurate 100% of the time.

events_moderator Does the procedure ever cause irreversible damage?

Dr_Caster If the procedure isn't done right, it can certainly cause a lot of problems, such as poor vision or halos.

Dr_Caster Also, an infection, scarring of the cornea.

Dr_Caster There are a number of technical things that can cause problems.

Dr_Caster That's why we advise people to go to doctors that have a lot of experience with this technique.

Dr_Caster In the hands of a very experienced surgeon, the procedure is extremely safe.

Dr_Caster There's probably a greater chance that the patient will get injured driving in their car to have the procedure done than there is to have a problem during the procedure.

events_moderator Does the patient experience any pain with the LASIK procedure?

Dr_Caster Patients vary in how they describe the sensation.

Dr_Caster Most of our patients say that they had no pain whatsoever.

Dr_Caster Although a rare patient will describe it as painful. Most patients say that they felt some pressure during the procedure but that it wasn't painful.

Dr_Caster Afterwards, very few people say that they have any pain after the procedure.

Dr_Caster A lot of people will say that their eyes feel scratchy during the healing period .. and this can go on for several months.

Dr_Caster And, it's due to dryness of the eyes.

Dr_Caster For some reason we don't know why the eyes get more dry during the healing period, but they certainly do.

Dr_Caster And, we prescribe moisturizing drops for this.

events_moderator How many times in general does a patient need to undergo the procedure?

Dr_Caster Almost everyone just has it done one time.

Dr Caster If your eyes are changing and if they change later in life, than you might have to have it done again when your eyes change.

Dr Caster About 10% of patients require an immediate touch-up procedure .. so, in other words, they get a response that's close to perfect, but not quite perfect.

Dr_Caster And, so, they need to come back and have a little bit more done.

events_moderator Are there certain ages that you do not recommend performing the surgery on, whether too young or too old?

Dr_Caster Yes.

Dr_Caster Teenagers generally have eyes that are still changing. So, you need to wait until your eyes have stopped changing ... in most, that's the early 20's.

Dr_Caster Even some people in their mid to late 20's will still be changing, so they should wait until their eyes should stop changing.

Dr_Caster There is no upper limit.

Dr_Caster It's when your eyes have stopped changing ... the youngest I have treated is around 18.

events_moderator What environmental factors can a person control in order to prevent vision problems?

Dr_Caster We know very little about what causes vision problems .. whether it's heredity or environment.

Dr_Caster There was a very recent study within the last month that talked about babies who .. where the light is kept on in the room where they're sleeping and 
later on in life , they may develop near sightedness.

Dr_Caster But, this is initial . we don't know if that will be verified by more studies.

Dr_Caster I personally believe that people who do an awful lot of reading in their teenage years or early 20's .. law students, people who work at a computer .. 
develop near sightedness.

Dr_Caster Also some women who get pregnant will develop near sightedness.

events_moderator Do you see increased problems lately, and do you attribute this to the increased computer usage we see today?

Dr_Caster I do not have any statistics to verify this.

Dr_Caster But, my impression is that people who work at a computer for long hours do show a shift towards near sightedness.

gr_paula Can LAsik surgery help blind people see?

Dr_Caster No.

Dr_Caster LASIK .. think of the eye like a camera ...

Dr_Caster ... if the camera is out of focus, than LASIK can help the camera to focus better. However, if the camera has other problems, LASIK cannot help that.

gr_paula How much does typical laser surgery cost?

Dr_Caster Prices seem to vary between around $4,000 and $5,000 for the two eyes combined.

Dr_Caster There are some centers that seem to charge considerably less than that and I'd be VERY, very wary of them.

Dr_Caster Centers that charge much less than that are generally cutting corners.

Dr_Caster And, you don't want to cut corners as far as your vision goes.

events_moderator Is it common to perform the surgery on only one eye?

Dr_Caster Some people only need the procedure done on one eye.

Dr_Caster It only costs about half of that.

events_moderator Can vision problems that are due to aging be corrected with laser treatment?

Dr_Caster No.

events_moderator How important is owning a pair of sunglasses?

Dr_Caster The ultra violet light from the sun is very bad for the eyes .. whether you've had LASIK or not.

Dr_Caster The ultra violet light causes cataracts and can also cause a disease of the retina known as Macular Degeneration.

Dr_Caster During the healing period from the LASIK, excessive exposure to ultraviolet light can cause a small change in the result.

Dr_Caster And, may necessitate an enhancement procedure.

Al_Pavy Do you find that many people are tinting their regular glasses? This seems to be the latest style.

Dr_Caster Well, I think tinting has always been popular. And, you can get glasses tinted to any degree that you want.

Dr_Caster There's no medical advantage or disadvantage to tinting the glasses.

Dr_Caster The filters for ultraviolet light are clear .. they have no color .. so tinting doesn't keep this light out.

Dr_Caster Tinting only keeps out the visible light. Ultraviolet light is invisible.

Dr_Caster If you're in a room full of ultraviolet light but no other type of light, the room would seem dark to you.

Al_Pavy Can staring at the sun really make you go blind?

Dr_Caster Yes. It can burn your retina.

Dr_Caster Even a short time of staring at the sun causes a burn .. can cause irreparable harm.

events_moderator How has laser eye surgery come about? Can you tell us the history?

Dr_Caster Okay ... IBM was working with the Excimer Laser to try to etch silicone computer chips.

Dr_Caster And, in 1982, an IBM researcher started testing this laser on different types of materials.

Dr_Caster And, what he saw was that you could remove tissue without causing any heat damage to the neighboring material.

Dr_Caster An ophthalmologist in NYC, Steven Trokel, heard about this research and realized that this could be used to change the shape of the cornea at the front 
of the eye.

Dr_Caster And, only 4 years later, the first patient was treated on an experimental basis and that was in 1987.

Dr_Caster And, the next ten years or so were spent perfecting the equipment and the techniques.

events_moderator Is there a particular country that has invested a particularly large amount of time and effort in the advancement of laser eye surgery?

Dr_Caster Well, laser eye surgery is now being performed in almost every country of the world.

Dr_Caster Most of the research has been done in the US.

Dr_Caster But, lasers have also been developed in Germany, and in Japan.

events_moderator Is this procedure prohibitively expensive to perform in a third-world country?

Dr_Caster Well, there are a number of lasers in Mainland China and in India. They use cheaper lasers that are easier to maintain.

Dr_Caster And, if you use that type of equipment, you can perform it on a much less costly basis.

Al_Pavy Is Lasik the only procedure for correcting bad vision?

Dr_Caster No.

Dr_Caster There is another procedure .. first of all, using the laser there is the PRK variation in which the laser energy is applied to the front surface of the cornea instead of the deep tissues.

Dr_Caster Also, in April of this year, the FDA approved another technique known as the Corneal Ring.

Dr_Caster This is composed of two small pieces of plastic which can be implanted into the cornea and can then change the shape of the cornea and correct near 
sightedness.

Dr_Caster It's made by a company called Keravision.

Dr_Caster But, there are only a limited number of sizes that are now available. So, it's use is rather limited.

Dr_Caster Also, you are implanting a foreign body into the cornea which must stay there in order to have an effect.

Dr_Caster The advantage is you can always take that piece of plastic out and the eye will return to more or less it's original state.

Dr_Caster And, that seems to be the biggest advantage of the Corneal Ring .. is that it is reversible.

allibeth Why should one do this laser surgery instead of simply wearing glasses or contacts? What are the added benefits?

Dr_Caster It is simply an alternative to glasses or contacts.

Dr_Caster The laser surgery is for people who don't want to wear glasses or contacts and would rather see with their own eyes .. rather than using these visual aids.

events_moderator Why do focusing problems occur?

Dr_Caster We don't know why people develop near sightedness, far sightedness or astigmatism .. there is definitely a hereditary component, and some type of 
environmental component as well.

Dr_Caster It's simply not understood.

events_moderator What happens during the LASIK treatment?

Dr_Caster Well, the treatment takes about 5 minutes per eye.

Dr_Caster Numbing drops are placed in the eye. There are no shots.

Dr_Caster The patient is then placed under the laser machine. A device known as a Keratome is placed on the eye and this makes the small flap. This is done 
automatically by the machine in about 10 seconds.

Dr_Caster Under the flap, the laser energy is then applied.

Dr_Caster Water is placed on the eye, and then the patient sits up.

Dr_Caster And, they're finished.

Dr_Caster They can go home right away and most people drive and go back to work the very next day.

bill_gray Can eye color permanently be changed?

Dr_Caster No.

Dr_Caster There are no techniques right now to do that.

graze Do you play any music during surgery?

Dr_Caster chuckles

Dr_Caster No.

Dr_Caster I like it to be quiet so I have total concentration.

Dr_Caster But, I speak to the patient throughout the whole procedure so they know what's going on and there are no surprises.

nickatnite_27 I have heard that laser surgery is not advisable to those who are nearsighted, but do a lot of reading? Is this true?

Dr_Caster Patients over 45 who have their distance vision fully corrected with contacts or with glasses or with a laser procedure will need to use reading glasses.

bill_gray Do you work with any charities?

Dr_Caster I work with a lot of charities.

Dr_Caster We have a program where every 3 months we've been donating the proceeds from a laser eye surgery to charity.

Dr_Caster In the last year we've donated to the American Diabetes Association, The Multiple Sclerosis Society, Cystic Fibrosis, and to one of the schools in our 
neighborhood.

events_moderator If a patient has astigmatism and is near-sighted, can you perform this surgery to help them?

Dr_Caster The answer is yes, we correct them both at the same time.

events_moderator Can buying non-prescription reading glasses be detrimental to vision?

Dr_Caster No.

Dr_Caster Non-prescription reading glasses are fine .. particularly if both of your eyes are the same.

Dr_Caster Because with those glasses, both eyes are the same.

gr_paula Who are your medical heroes?

Dr_Caster Dr. Alexander Fleming.

Dr_Caster He's the British doctor that discovered Penicillin around the time of World War II.

Dr_Caster It's probably the greatest discovery in modern medicine.

Dr_Caster Going WAY back, there's a very brave doctor named Ignaz Semmelweiss. He was a doctor that lived in Vienna in the 1800's.

Dr_Caster And, back then many women were dying during childbirth of a mysterious illness and Doctor Semmelweiss figured out that this was due to something that the doctors were spreading from one patient to the next patient.

Dr_Caster Back then they didn't know what an infection was. Nobody washed their hands.

Dr_Caster And, he was ridiculed by everybody.

Dr_Caster But, he was right.

Dr_Caster And, as soon as he started the doctors all washing their hands, these mysterious deaths stopped. It's quite a remarkable story.

graze What do you think is the biggest medical problem facing the world today?

Dr_Caster Malnutrition .. which more often than not, is caused by warfare.

allibeth Can this procedure be done to help blind people's vision?

Dr_Caster No.

Dr_Caster If the camera is not capable of working, it doesn't matter if you can focus the camera right .. if the rest of the camera's not working, the camera is not going to work.

events_moderator What do you think about that movie where Val Kilmer got cured of his blindness?

Dr_Caster I didn't see the movie.

gr_paula I see that you studied in Russia. What are the differences in healthcare procedures over there?

Dr_Caster That's a tough question.

Dr_Caster They are much more primitive in the technology that the average patient has access to.

Dr_Caster In specialized areas, where they want to spend the money, they can purchase the same technology that we use.

Dr_Caster But, for the most part, they choose not to do that.

Dr_Caster So, they are using equipment that is many, many years old or just not as expensive and sophisticated.

bill_gray What advice can you give to someone just starting out in the medical field who is interested in opthamology?

Dr_Caster Spend time with an ophthalmologist and make sure that's something you want to dedicate your life to.

graze Have you ever felt that the medical profession suffers because people are more concerned with the almighty dollar than the craft?

Dr_Caster Most doctors that I know are extremely dedicated to helping their patients. I think there are certainly bad apples in every group.

Dr_Caster But, in the medical field, I think the bad apples are really few and far between.

Dr_Caster I think that managed care, and in general an effort to control the costs is making it very difficult to provide the highest quality care in some situations.

events_moderator How has laser surgery developed in recent years?

Dr_Caster There are refinements in the laser, and in the way that the laser is patterned on to the surface of the cornea.

Dr_Caster This is a steady, ongoing process. And, I'm sure it will continue for many years into the future.

allibeth Where do you see this technology in 5 years?

Dr_Caster Whereas today, over 95% of the patients are able to pass their driver's tests without glasses, I expect that to be 100% in five years.

Dr_Caster I think we will become more and more accurate in our results during the next five years.

Dr_Caster Patients who we are unable to treat today for various technical reasons, we will, hopefully, be able to treat within the next five years.

Dr_Caster I think that sometime in the not too distant future, we will walk into a museum and we will see displays of glasses and contact lenses.

Dr_Caster And, little kids will ask their parents or grandparents what those things were for.

Dr_Caster Because glasses and contact lenses will just become another outdated technology.

Dr_Caster Whether that's in 20 years or 50 years, I don't know.

Dr_Caster But, this technique is so powerful, that I think it's going to become extremely widespread.

allibeth I read you grew up in South Africa. In what ways do the medical systems differ there from here?

Dr_Caster I grew up in South Florida.

Dr_Caster I have no idea what the situation in South Africa is.

graze Do you have a certain goal in eye surgery that you would like to accomplish?

Dr_Caster Yes. I would like every patient to be able to see perfectly with their own eyes.

events_moderator Can vision deteriorate after having the correction surgery?

Dr_Caster Yes. Most people .. once they reach the age where their eyes are stable, their eyes do stay the same for the rest of their lives.

Dr_Caster But, there are some rare patients whose eyes will change whether or not they have the surgery. And, if that happens, they'll need to have a touch-up 
done.

graze What else is laser surgery used for?

Dr_Caster Lasers are used for many things in eye care. Diabetic disease is treated with a laser. After cataract surgery, many patients need a laser treatment to have 
perfect vision.

Dr_Caster Glaucoma can be treated with lasers.

gr_paula What has been your strangest experience with a patient so far?

gr_paula Where can I find more information about laser surgery?

Dr_Caster They can go to our web site ... which is www.castervision.com.

Dr_Caster Also, if they'd like to purchase my book, it's the most widely read book in the entire US on the subject of laser vision correction .. it's called "The Eye Laser Miracle."

Dr_Caster It's published by Random House books and is in many bookstores. It can also be purchased through amazon.com or any other online bookseller.

Moderator Dr. Caster, thank you for joining us. Please join us again tomorrow at 12:00pm PDT/3:00 EDT when our guest will be Dr. Andrew Steenblock discussing the treatment and rehabilitation of brain injuries.

Dr_Caster Thank you. Bye!