REFRACTIVE SURGERY – LASIK, PRK, LASEK, EPILASIK, LENS EXTRACTION
WHAT REFRACTIVE SURGERY SERVICES ARE OFFERED AT THE ASIAN EYE INSTITUTE?
The Refractive Surgery Service of the Asian Eye Institute manages vision problems (errors of refraction) such as nearsightedness (myopia), farsightedness (hyperopia) and astigmatism through surgery. The most popular procedure in refractive surgery is Laser Refractive Surgery or Laser Vision Correction (LASIK, PRK, LASEK, EpiLASIK). Other procedures include refractive lens exchange, insertion of a phakic intraocular lens and incisional keratotomy procedures such as radial keratotomy (RK), arcuate keratotomy (AK) and limbal relaxing incisions (LRI).
WHAT IS LASER VISION CORRECTION OR LASER REFRACTIVE SURGERY?
Laser vision correction is a surgical procedure that uses an excimer laser to reshape the cornea by removing a controlled amount of tissue in order to alter its refractive power. The most common surgical techniques are LASIK (laser in situ keratomileusis), PRK (photorefractive keratectomy) and LASEK (laser epithelial keratomileusis). More recently, we introduced a NEW innovative technique called EPILASIK. The method of exposing the deeper corneal layer differentiates these four techniques of laser vision correction.
WHAT ARE THE DIFFERENCES BETWEEN LASIK, PRK, LASEK AND EpiLASIK?
Each patient undergoes a screening test wherein the corneal thickness is measured. A patient with thick corneas can undergo LASIK. For patients with thin corneas, it is not safe to cut a thick flap because this may weaken the eye permanently. The safer technique is to create an ultrathin flap (EPILASIK or LASEK) or not to create a flap at all (PRK).
In LASIK, a special device called a microkeratome is used to create a thick corneal flap. The flap is retracted and the laser applied on the remaining corneal bed. The flap is then returned to its original position. The cornea has special properties that allow the flap to bond naturally without the use of stitches. LASIK is the most popular laser procedure because of the quick healing time, immediate visual improvement and minimal discomfort associated with the procedure. One day after LASIK, patients see very well, experience almost no pain and can return to their usual activities.
In PRK, the surface layer of the cornea (epithelium) is gently peeled using a special alcohol solution and removed prior to laser treatment. The epithelial cells grow back within 5-7 days after surgery. Vision slowly improves and patients typically experience a significant amount of pain or discomfort during this period.
In LASEK, the surface layer of the cornea (epithelium) is gently peeled as an intact sheet using an alcohol solution. Rather than remove this sheet of cells after laser treatment as in PRK, this sheet is placed back on the treated surface to act as a protective covering during the healing period. Compared to PRK, the presence of the epithelial sheet after LASEK has been reported to cause less pain and discomfort, hasten visual recovery and provide an additional layer of protection from infection.
EpiLASIK is the newest technique in laser refractive surgery. The same microkeratome utilized in LASIK is used to create an ultrathin flap composed of epithelial cells (surface cells of the cornea). This ultrathin flap is retracted, laser applied and repositioned back over the cornea. We place a bandage contact lens to protect the cornea. Post-op pain is less compared to PRK and LASEK. The cornea heals in three days and vision improves in one week. It is believed that Epilasik combines the advantages of both LASIK and PRK/LASEK.
The potential for 20/20 vision is equivalent between LASIK, PRK, LASEK or EpiLASIK. Individual response to healing is a big factor in visual clarity. The healing time is fastest with LASIK, then EpiLASIK, LASEK and slowest in PRK. The amount of discomfort or pain is reverse, the most pain after PRK, then LASEK, EpiLASIK, and virtually no pain in LASIK.
WHAT IS THE DIFFERNCE BETWEEN CONVENTIONAL AND CUSTOMIZED/WAVEFRONT VISION CORRECITON?
Laser software used for treatment can either be Conventional or Customized/Wavefront (Personalized or Aspheric). A comprehensive evaluation will be performed to determine whether the patient is a good candidate and which type of laser vision correction software is most suitable for him. The patient then makes the decision if he/she wants the conventional/regular treatment or the upgraded customized treatment.
The front part of the cornea alone does not determine how well the eye can focus. The inner parts of the eye, and how they fit and work together, also contribute to the focusing power of the eye. Glasses and contact lenses change the way light bends even before it hits the eye. Similarly, conventional treatment reshapes the eye based mainly on the contour of the front part of the eye. These methods of correcting errors of refraction can help you see better, but do not consider the inner parts of the eye that could also contribute to the vision clarity or sharpness.
Customized or Wavefront (Aspheric or Personalized) vision correction is a higher level of treatment. Specialized diagnostic instruments gather and analyze information on the inner parts of the eye. Light reflected from the inner eye is measured as a “wavefront”. Mathematical equations interpret the wavefront to deliver a treatment that is tailored to these specific eye details. The customized treatment may therefore result in vision better than with glasses, contact lenses, or conventional laser treatment. Personalized laser surgery allows us to treat successfully patients with a large amount of higher order aberrations/distortions and complicated or irregular astigmatism. Aspheric laser correction allows us to treat patients with large dim light pupils and minimize the occurrence of night-time glare and haloes.
WHAT LASER MACHINE DOES AEI USE?
Asian Eye Institute has the advanced Bausch and Lomb Technolas Zyoptix 100 excimer laser. It is the only center in the Philippines with the Z100. This top-of-the-line laser can perform conventional, aspheric or personalized treatment for nearsightedness, farsightedness and astigmatism. In addition, it has a multi-dimensional eye-tracker and the patented Iris Recognition technology that automatically compensates for changes in eye position and movement during laser treatment. These revolutionary features provide a higher level of accuracy in laser pulse placement that can translate to better vision results. Zyoptix with Iris Recognition (IR) is the brand name of Bausch and Lomb’s customized treatment. Asian Eye Institute has, by far, the most extensive experience in Zyoptix customized LASIK in the Philippines.
WHO WILL PERFORM YOUR LASER TREATMENT?
Asian Eye Institute has a full-time laser refractive surgeon who performs all the laser refractive treatments. Dr. Ang graduated from subspecialty training at the Massachusetts Eye and Ear Infirmary, Harvard Medical School. He is part of the Asian Refractive Committee, a prestigious group of eye surgeons, representing each country in Asia, dedicated to advancing the science of laser vision correction in the Asian Region. He has performed several international LASIK clinical trials, bringing Asian Eye and the Philippines to the forefront of cutting edge research in laser technology.
WHAT ARE THE BENEFITS OF LASER VISION CORRECTION?
Laser vision correction gives clear vision without the daily hassles of eyeglasses and contact lenses and allows a person to:
• Enjoy sports like golf, badminton, diving, swimming, trekking, & rock-climbing
• Experience convenience in travel; no more contact lens kits and solutions;
• Remove the discomfort of allergies, eye redness, dry eye caused by contact lenses;
• Improve one’s appearance and eliminates the pressure on the nose bridge caused by eyeglasses;
• Save on the accumulated cost of buying glasses and contact lenses for many years to come; and
• Enjoy a better quality of life
IS LASER REFRACTIVE SURGERY SAFE?
LASIK and PRK have undergone extensive USFDA testing and investigation and are now considered by ophthalmologists worldwide as a relatively safe and effective surgical procedure. The risks in laser refractive surgery are similar to those of other eye surgeries. These include infection, over/undercorrection, flap problems, glare, haloes and dry eye. Based on a review of past surgeries done, approximately 97% of patients achieve 20/20 vision after laser treatment in Asian Eye.
WHAT OTHER SAFETY FEATURES DOES AEI HAVE?
AEI offers the most sterile laser environment in the country. A dedicated laminar flow air conditioning unit specifically designed for operating room use ensures that possible contaminants in the air inside the refractive laser suite is kept to a minimum.
AEI is the first and only eye center in the Philippines with the top-of-the-line Bausch and Lomb Technolas 217 Zyoptix 100 laser. This laser has the patented Iris Recognition Technology and multi-dimensional eye tracker that offer increased safety and better visual results.
The AEI staff is fully trained to perform a thorough evaluation to determine if a patient is eligible for refractive surgery. The AEI doctor will discuss thoroughly with the patient any conditions that may predispose him to any complications, so that options and realistic expectations are considered before he decides to proceed with the surgery.
WHAT IF THE EYE MOVES DURING THE PROCEDURE?
Our laser has a special device called a Multi-Dimensional eye tracker that detects and follows eye movement in three planes (x-y-z axis), thereby ensuring accurate laser pulse placement during the entire procedure.
IS LASER REFRACTIVE SURGERY PAINFUL?
No. Patients typically experience little or no pain during surgery since adequate anesthesia is given while the procedure is being performed. In addition, little or no pain is experienced after the surgery since the flap protects the deeper layers of the cornea.
After surgery, it is common to experience a gritty feeling in the eye when blinking. It is unusual to experience severe pain after LASIK.
In PRK, LASEK or EpiLASIK, some discomfort may be experienced during the immediate postoperative period but this is expected to subside as the corneal surface heals.
WILL I GET PERFECT VISION AFTER LASER CORRECTION?
Because of differences in laser-tissue interaction and variations in wound healing, it is impossible to guarantee perfect vision to everybody. Statistics from previous treatments show that approximately 97% of patients who underwent customized Zyoptix LASIK at Asian Eye achieve 20/20 vision.
If treatment for a patient does not result in full correction, he may opt to wear glasses, contact lenses or have additional laser surgery (enhancement procedure). Published reports state that approximately 5% of patients undergo an enhancement or “touch up” procedure to improve visual results. AEI performs enhancement procedures for patients who have already had previous laser vision correction.
WHAT IS THE TIME COMMITMENT INVOLVED IN LASER REFRACTIVE SURGERY?
Prior to Surgery
The initial visit may take up to three hours for a thorough eye examination. It is advised that arrangements be made for someone to take the patient home, since part of the examination would require putting eye drops that may blur vision for a few hours and make driving difficult or unsafe. In addition, it is advised that the patient discontinue using contact lenses (1 week for soft contact lenses and 3 weeks for hard/rigid gas permeable contact lenses) prior to the scheduled examination to minimize the effect of the lenses on the test results.
On the day of the surgery
Refractive surgery is done on an outpatient basis. While the surgery itself may take only 5 minutes per eye, the actual stay may take up to two hours to accommodate preparations before the surgery and resting time before the patient is sent home. Both eyes may undergo surgery on the same day.
After surgery
Several post-operative visits will be scheduled to monitor recovery. The patient will be advised on precautions and medications during the recovery period.
Visual recovery varies from patient to patient. With LASIK, majority of patients can return to their usual activities a day or two after surgery. In PRK, LASEK or EpiLASIK, recovery usually lasts up to four days after the procedure. It is not unusual for vision to fluctuate following surgery, but normally it stabilizes within a few weeks.
WHAT ABOUT READING GLASSES?
Presbyopia is a condition wherein the ciliary muscles weaken and the natural lens inside the eye loses its flexibility. This results in gradual difficulty in reading small print or viewing small objects such as cellphones or watches up close. It is a natural consequence of aging that cannot be reversed. Beginning at 40 years of age and above, patients with good distance vision start wearing reading glass and those with eyeglasses convert to bifocals or progressive glasses.
CAN LASER SURGERY MAKE ME SEE NEAR WITHOUT READING GLASSES?
Numerous claims have been forwarded by different laser companies and surgeons about laser refractive surgery being able to eliminate the need for reading glasses. For hyperopia or farsighted people, those with Plus (+) grade, significant progress has been made. However, for the majority of people who are nearsighted (Minus grade), the solution remains elusive. Results have been presented in different scientific meetings but no universally applicable and replicable treatment has been accepted by the eye doctors’ community. Unfortunately, the answer to the above question if you are nearsighted or myopic is still NO. There is no consistent solution for the myopic patient that will give perfect distance and near vision in the same eye if they are in the presbyopic or above 40 age group.
Currently acceptable treatments would entail some amount of sacrifice. For a patient above 40 years of age, we present three options for laser vision correction. Full correction which results in very good distance vision but total dependence on reading glasses. Second, compromise or intentional undercorrection makes a patient slightly nearsighted by about 1.00 grade. Distance vision clarity in both eyes is mildly sacrificed to preserve some near vision without reading glasses. Third, monovision entails treating the dominant eye with full correction and the non-dominant eye intentionally nearsighted by about 1.50 grade.
REFRACTIVE SURGERY – LASIK, PRK, LASEK, EPILASIK, LENS EXTRACTION
WHAT REFRACTIVE SURGERY SERVICES ARE OFFERED AT THE ASIAN EYE INSTITUTE?
The Refractive Surgery Service of the Asian Eye Institute manages vision problems (errors of refraction) such as nearsightedness (myopia), farsightedness (hyperopia) and astigmatism through surgery. The most popular procedure in refractive surgery is Laser Refractive Surgery or Laser Vision Correction (LASIK, PRK, LASEK, EpiLASIK). Other procedures include refractive lens exchange, insertion of a phakic intraocular lens and incisional keratotomy procedures such as radial keratotomy (RK), arcuate keratotomy (AK) and limbal relaxing incisions (LRI).
WHAT IS LASER VISION CORRECTION OR LASER REFRACTIVE SURGERY?
Laser vision correction is a surgical procedure that uses an excimer laser to reshape the cornea by removing a controlled amount of tissue in order to alter its refractive power. The most common surgical techniques are LASIK (laser in situ keratomileusis), PRK (photorefractive keratectomy) and LASEK (laser epithelial keratomileusis). More recently, we introduced a NEW innovative technique called EPILASIK. The method of exposing the deeper corneal layer differentiates these four techniques of laser vision correction.
WHAT ARE THE DIFFERENCES BETWEEN LASIK, PRK, LASEK AND EpiLASIK?
Each patient undergoes a screening test wherein the corneal thickness is measured. A patient with thick corneas can undergo LASIK. For patients with thin corneas, it is not safe to cut a thick flap because this may weaken the eye permanently. The safer technique is to create an ultrathin flap (EPILASIK or LASEK) or not to create a flap at all (PRK).
In LASIK, a special device called a microkeratome is used to create a thick corneal flap. The flap is retracted and the laser applied on the remaining corneal bed. The flap is then returned to its original position. The cornea has special properties that allow the flap to bond naturally without the use of stitches. LASIK is the most popular laser procedure because of the quick healing time, immediate visual improvement and minimal discomfort associated with the procedure. One day after LASIK, patients see very well, experience almost no pain and can return to their usual activities.
In PRK, the surface layer of the cornea (epithelium) is gently peeled using a special alcohol solution and removed prior to laser treatment. The epithelial cells grow back within 5-7 days after surgery. Vision slowly improves and patients typically experience a significant amount of pain or discomfort during this period.
In LASEK, the surface layer of the cornea (epithelium) is gently peeled as an intact sheet using an alcohol solution. Rather than remove this sheet of cells after laser treatment as in PRK, this sheet is placed back on the treated surface to act as a protective covering during the healing period. Compared to PRK, the presence of the epithelial sheet after LASEK has been reported to cause less pain and discomfort, hasten visual recovery and provide an additional layer of protection from infection.
EpiLASIK is the newest technique in laser refractive surgery. The same microkeratome utilized in LASIK is used to create an ultrathin flap composed of epithelial cells (surface cells of the cornea). This ultrathin flap is retracted, laser applied and repositioned back over the cornea. We place a bandage contact lens to protect the cornea. Post-op pain is less compared to PRK and LASEK. The cornea heals in three days and vision improves in one week. It is believed that Epilasik combines the advantages of both LASIK and PRK/LASEK.
The potential for 20/20 vision is equivalent between LASIK, PRK, LASEK or EpiLASIK. Individual response to healing is a big factor in visual clarity. The healing time is fastest with LASIK, then EpiLASIK, LASEK and slowest in PRK. The amount of discomfort or pain is reverse, the most pain after PRK, then LASEK, EpiLASIK, and virtually no pain in LASIK.
WHAT IS THE DIFFERNCE BETWEEN CONVENTIONAL AND CUSTOMIZED/WAVEFRONT VISION CORRECITON?
Laser software used for treatment can either be Conventional or Customized/Wavefront (Personalized or Aspheric). A comprehensive evaluation will be performed to determine whether the patient is a good candidate and which type of laser vision correction software is most suitable for him. The patient then makes the decision if he/she wants the conventional/regular treatment or the upgraded customized treatment.
The front part of the cornea alone does not determine how well the eye can focus. The inner parts of the eye, and how they fit and work together, also contribute to the focusing power of the eye. Glasses and contact lenses change the way light bends even before it hits the eye. Similarly, conventional treatment reshapes the eye based mainly on the contour of the front part of the eye. These methods of correcting errors of refraction can help you see better, but do not consider the inner parts of the eye that could also contribute to the vision clarity or sharpness.
Customized or Wavefront (Aspheric or Personalized) vision correction is a higher level of treatment. Specialized diagnostic instruments gather and analyze information on the inner parts of the eye. Light reflected from the inner eye is measured as a “wavefront”. Mathematical equations interpret the wavefront to deliver a treatment that is tailored to these specific eye details. The customized treatment may therefore result in vision better than with glasses, contact lenses, or conventional laser treatment. Personalized laser surgery allows us to treat successfully patients with a large amount of higher order aberrations/distortions and complicated or irregular astigmatism. Aspheric laser correction allows us to treat patients with large dim light pupils and minimize the occurrence of night-time glare and haloes.
WHAT LASER MACHINE DOES AEI USE?
Asian Eye Institute has the advanced Bausch and Lomb Technolas Zyoptix 100 excimer laser. It is the only center in the Philippines with the Z100. This top-of-the-line laser can perform conventional, aspheric or personalized treatment for nearsightedness, farsightedness and astigmatism. In addition, it has a multi-dimensional eye-tracker and the patented Iris Recognition technology that automatically compensates for changes in eye position and movement during laser treatment. These revolutionary features provide a higher level of accuracy in laser pulse placement that can translate to better vision results. Zyoptix with Iris Recognition (IR) is the brand name of Bausch and Lomb’s customized treatment. Asian Eye Institute has, by far, the most extensive experience in Zyoptix customized LASIK in the Philippines.
WHO WILL PERFORM YOUR LASER TREATMENT?
Asian Eye Institute has a full-time laser refractive surgeon who performs all the laser refractive treatments. Dr. Ang graduated from subspecialty training at the Massachusetts Eye and Ear Infirmary, Harvard Medical School. He is part of the Asian Refractive Committee, a prestigious group of eye surgeons, representing each country in Asia, dedicated to advancing the science of laser vision correction in the Asian Region. He has performed several international LASIK clinical trials, bringing Asian Eye and the Philippines to the forefront of cutting edge research in laser technology.
WHAT ARE THE BENEFITS OF LASER VISION CORRECTION?
Laser vision correction gives clear vision without the daily hassles of eyeglasses and contact lenses and allows a person to:
• Enjoy sports like golf, badminton, diving, swimming, trekking, & rock-climbing
• Experience convenience in travel; no more contact lens kits and solutions;
• Remove the discomfort of allergies, eye redness, dry eye caused by contact lenses;
• Improve one’s appearance and eliminates the pressure on the nose bridge caused by eyeglasses;
• Save on the accumulated cost of buying glasses and contact lenses for many years to come; and
• Enjoy a better quality of life
IS LASER REFRACTIVE SURGERY SAFE?
LASIK and PRK have undergone extensive USFDA testing and investigation and are now considered by ophthalmologists worldwide as a relatively safe and effective surgical procedure. The risks in laser refractive surgery are similar to those of other eye surgeries. These include infection, over/undercorrection, flap problems, glare, haloes and dry eye. Based on a review of past surgeries done, approximately 97% of patients achieve 20/20 vision after laser treatment in Asian Eye.
WHAT OTHER SAFETY FEATURES DOES AEI HAVE?
AEI offers the most sterile laser environment in the country. A dedicated laminar flow air conditioning unit specifically designed for operating room use ensures that possible contaminants in the air inside the refractive laser suite is kept to a minimum.
AEI is the first and only eye center in the Philippines with the top-of-the-line Bausch and Lomb Technolas 217 Zyoptix 100 laser. This laser has the patented Iris Recognition Technology and multi-dimensional eye tracker that offer increased safety and better visual results.
The AEI staff is fully trained to perform a thorough evaluation to determine if a patient is eligible for refractive surgery. The AEI doctor will discuss thoroughly with the patient any conditions that may predispose him to any complications, so that options and realistic expectations are considered before he decides to proceed with the surgery.
WHAT IF THE EYE MOVES DURING THE PROCEDURE?
Our laser has a special device called a Multi-Dimensional eye tracker that detects and follows eye movement in three planes (x-y-z axis), thereby ensuring accurate laser pulse placement during the entire procedure.
IS LASER REFRACTIVE SURGERY PAINFUL?
No. Patients typically experience little or no pain during surgery since adequate anesthesia is given while the procedure is being performed. In addition, little or no pain is experienced after the surgery since the flap protects the deeper layers of the cornea.
After surgery, it is common to experience a gritty feeling in the eye when blinking. It is unusual to experience severe pain after LASIK.
In PRK, LASEK or EpiLASIK, some discomfort may be experienced during the immediate postoperative period but this is expected to subside as the corneal surface heals.
WILL I GET PERFECT VISION AFTER LASER CORRECTION?
Because of differences in laser-tissue interaction and variations in wound healing, it is impossible to guarantee perfect vision to everybody. Statistics from previous treatments show that approximately 97% of patients who underwent customized Zyoptix LASIK at Asian Eye achieve 20/20 vision.
If treatment for a patient does not result in full correction, he may opt to wear glasses, contact lenses or have additional laser surgery (enhancement procedure). Published reports state that approximately 5% of patients undergo an enhancement or “touch up” procedure to improve visual results. AEI performs enhancement procedures for patients who have already had previous laser vision correction.
WHAT IS THE TIME COMMITMENT INVOLVED IN LASER REFRACTIVE SURGERY?
Prior to Surgery
The initial visit may take up to three hours for a thorough eye examination. It is advised that arrangements be made for someone to take the patient home, since part of the examination would require putting eye drops that may blur vision for a few hours and make driving difficult or unsafe. In addition, it is advised that the patient discontinue using contact lenses (1 week for soft contact lenses and 3 weeks for hard/rigid gas permeable contact lenses) prior to the scheduled examination to minimize the effect of the lenses on the test results.
On the day of the surgery
Refractive surgery is done on an outpatient basis. While the surgery itself may take only 5 minutes per eye, the actual stay may take up to two hours to accommodate preparations before the surgery and resting time before the patient is sent home. Both eyes may undergo surgery on the same day.
After surgery
Several post-operative visits will be scheduled to monitor recovery. The patient will be advised on precautions and medications during the recovery period.
Visual recovery varies from patient to patient. With LASIK, majority of patients can return to their usual activities a day or two after surgery. In PRK, LASEK or EpiLASIK, recovery usually lasts up to four days after the procedure. It is not unusual for vision to fluctuate following surgery, but normally it stabilizes within a few weeks.
WHAT ABOUT READING GLASSES?
Presbyopia is a condition wherein the ciliary muscles weaken and the natural lens inside the eye loses its flexibility. This results in gradual difficulty in reading small print or viewing small objects such as cellphones or watches up close. It is a natural consequence of aging that cannot be reversed. Beginning at 40 years of age and above, patients with good distance vision start wearing reading glass and those with eyeglasses convert to bifocals or progressive glasses.
CAN LASER SURGERY MAKE ME SEE NEAR WITHOUT READING GLASSES?
Numerous claims have been forwarded by different laser companies and surgeons about laser refractive surgery being able to eliminate the need for reading glasses. For hyperopia or farsighted people, those with Plus (+) grade, significant progress has been made. However, for the majority of people who are nearsighted (Minus grade), the solution remains elusive. Results have been presented in different scientific meetings but no universally applicable and replicable treatment has been accepted by the eye doctors’ community. Unfortunately, the answer to the above question if you are nearsighted or myopic is still NO. There is no consistent solution for the myopic patient that will give perfect distance and near vision in the same eye if they are in the presbyopic or above 40 age group.
Currently acceptable treatments would entail some amount of sacrifice. For a patient above 40 years of age, we present three options for laser vision correction. Full correction which results in very good distance vision but total dependence on reading glasses. Second, compromise or intentional undercorrection makes a patient slightly nearsighted by about 1.00 grade. Distance vision clarity in both eyes is mildly sacrificed to preserve some near vision without reading glasses. Third, monovision entails treating the dominant eye with full correction and the non-dominant eye intentionally nearsighted by about 1.50 grade.