“Lasik ” comes from “Laser Assisted In-Situ Keratomileusis“. This is the most popular method for the correction of visual errors. The name of LASIK was first described by Dr Pallikaris of Greece, although the procedure was done by various surgeons around the world before then.
Lasik consists of two procedures namely microlamellar keratoplasty and excimer laser photorefractive keratoplasty. Classical keratomileusis is a lathing procedure originating in 1949 with the work of Dr. Barraquer of Bogota, Columbia. In 1977 this procedure was introduced into the United States where after Louis Ruiz did further advancements in 1982 as well as 1987. Since then technology has constantly been improving up to the point where it can now be regarded as a feasible safe option in refractive surgery.
Dr. Danie Maritz was one of the pioneers of this procedure in the world and the first to perform it in South Africa with a Nidek laser.
Lasik surgery is subject to risks as in all types of surgery. The clarity of vision will fluctuate during the day and from day to day during the healing period. Sensitivity to light and an increased glare in the evening might also be experienced initially during the healing phase.
The new generation femtosecond intralase excimer lasers (flying spot, eye tracking and topography guided), can now correct hyperopia and astigmatism much better than with the older generation lasers.
One hundred percent post operative vision can not be guaranteed and the possiblity might exist that you will need some corrective lenses. Both eyes are usually operated on at one time, but only one can be done at a time as well. It is more comfortable for the patient and it heals quicker.
PRE OPERATIVE INSTRUCTIONS
During a consultation it will be confirmed whether you are a good candidate for lasik. Once this has been established, the operation procedure as well as all the relevant costs will be explained. As this operation can be considered by medical insurance as a “functional improvement of lifestyle” operation and not a “life supporting” operation, they might not all be keen to carry the full cost of this procedure. Therefore, you have to confirm with your medical insurers what their position will be.
Once all the above are clear, a complete eye evaluation will be performed to ensure your eyes are healthy and suitable for the specific procedure. You will receive drops in your eyes after which certain measurements will be taken of the cornea and eye to further determine if your eyes will be suitable and to plan the operation. If you wear hard or gas permeable lenses, they should be removed for a minimum of one week where as soft contacts should not be worn for a minimum of three days prior to the day on which the measurements will be taken as well as for the actual operation.
Do not wear any mascara or eye makeup on the day of surgery. The Lasik procedure is done on an outpatient basis. Topical eye drops are used to anaesthetize the eye and the procedure will take approximately 30 – 45 minutes but anticipate a 2 – 3 hour stay at the hospital.
The surgical procedure consists of first creating an anterior lamellar corneal cap (or flap) of 8.5 mm in diameter and 160 microns in thickness using a microkeratome. The flap is then hinged over followed by the second step which is the refractive correction performed with the excimer laser.
The excimer laser sculpts or reshapes the central cornea. The treated area is washed with a balanced salt solution and covered with the original flap. It takes a couple of minutes for the corneal flap to adhere itself to the rest of the cornea. In a couple of days the cornea will be crystal clear and an almost imperceptible scar will barely be seen.
Any of the above procedures can be stopped for instance if the conjunctiva is too loose resulting in the inability of the suction ring to fixate properly on the eye.
You will need to wear an eye shield for 2 nights and use eye drops for 3 days. You can go back to work again the following day. It takes between 1 and 14 days for the vision to stabilize in most cases.
The size of the eyeball and eye slit may be too small to get good suction in which case the procedure might be changed to a PRK or Lasek (epi-flap) procedure. With the PRK or Lasek procedure the end visual result is also good but it will be painful initially and take much longer to heal. If the microkeratome becomes stuck along the way or the cut or flap is not as good as expected, the flap can be repositioned and left to heal. The procedure can then safely be repeated again after 3 months.
In a few cases where the vision is not good enough post operatively, an enhancement procedure can be done if necessary, however this is seldom required. The incidents of enhancement procedures is less than 6%. In extremely rare instances, corneal scarring may occur. This may then require further treatment.
BENEFITS OF REFRACTIVE SURGERY
Refractive surgery normally enhances people’s lives by giving them more freedom through natural vision. Some people have difficulty adjusting to glasses or contact lenses. This can be for a variety of reasons such as the shape of their eyeball, nose or face. It can also be because of the lubrication of their eyes, living or working environment, or the type of work or sport they participate in. It takes away the fear that you might be visually handicapped and embarrassed when you lose your glasses or contact lenses.
Most people simply don’t like thick glasses or contacts. Whether it be simple appearance or their ability to take part in certain sports such as swimming, tennis, skiing, scuba diving, wind surfing, squash, rugby, soccer or some other physical activity. In some cases, certain professions require a minimum level of visual acuity without corrective lenses, such as pilots, fire-fighters or police officers.
HOW DOES THE LASER WORK?
The excimer laser uses a mixture of argon and fluoride gasses to produce a beam of ultraviolet light. Energy is produced emitting a narrow, uniform light beam which, when focused through a lens system, produces vaporisation of corneal tissue. By controlling the energy, size and shape of the laser beam, one can reshape the cornea so that the light coming through it is bent to focus properly on the retina.
Lasik combines the precision of the excimer laser with the benefits of Lamellar Keratoplasty. It is now the procedure of choice world wide. This procedure has the distinct advantage that it allows quicker healing than with PRK (Photorefractive Keratoplasty). Bowmans membrane (one of the layers of the cornea that provides it with strength) is also preserved in this procedure and this may also be an added advantage. This procedure requires more skill, training and experience and is therefore not done at all centers. It is therefore essential that you check on the training and number of operations that the surgeon of your choice has done before the operation is done.
WHERE IS THE PROCEDURE DONE?
Being a microsurgical eye operation, it has to be done in a sterile area that is suitable equipped for these types of operations.