Eye Laser – Technology Creating More Predictable Results
Author : Dr Japie Grové –
LASIK or Refractive Laser Surgery is certainly one of the most fascinating procedures in modern medicine. It has been showed to be one of the most accurate and successful surgeries performed in the world. But with good results come great expectation! Advances in technology in laser refractive surgery are generally aimed at improving the predictability of the procedure. Improvements include:
The laser used in LASIK surgery is an Excimer laser, this laser can remove as little as 0.25 micrometres of the cornea at a time making it extremely accurate. The initial broad beam lasers are generally replaced these days with slit scanning or spot scanning laser beams. These lasers give a smoother laser surface and make wavefront correction possible.
Wavefront aberrations are abnormalities in the focus system of the eye that cannot be corrected with spectacles. It is also referred to as Higher Order Aberrations. Correcting these higher order aberrations can improve the quality of vision in certain patients. To detect the wavefront abnormalities, special equipment are used to create a customised map(see image on right) of each eye. This information is then used to adjust the laser specifically for each eye.
To enable an accurate laser ablation all modern refractive lasers have an eye tracking system. These systems identify an area of the iris or pupil and will adjust to tiny eye movements during surgery. If any big movement occur, the laser will stop automatically and resume treatment as soon as the eye has been aligned again. (see image on right)
Cutting the Flap:
Cutting the corneal flap during LASIK surgery is one of the most crucial steps during the procedure. Exact depth and size is most important and will impact a great deal on the final result. These days this step can either be done with Femtosecond Laser or modern Microkeratomes. Both these systems give equal visual results with a very good safety and accuracy profile.
Although technology helps us a lot to make LASIK surgery safer and more predictable, the skill of the surgeon cannot be left out of the equation. Staying in touch with technology as well as understanding and mastering the “art” of refractive surgery by the individual surgeon will always carry most of the weight in determining the outcome of the surgery.