LASIK procedures are used to re-shape the cornea, the dome shaped covering of the eye, to correct refractive errors like near-sightedness, far-sightedness and astigmatism. Wavefront technology, a technique that uses three-dimensional images in conjunction with laser to correct common refractive errors, allows more accurate mapping of the contours of the eye. Sometimes called custom LASIK, wavefront procedures can detect high-order aberrations in the eye, All About Vision states. Wavefront techniques are used both to evaluate the surface of the cornea, the part of the eye treated by LASIK, and to treat the eye.
Evaluation
Wavefront technology diagnoses the surface of the cornea by analyzing light waves aimed into the eye that bounce off the retina and back through the lens, pupil and cornea. Light passes through a sensing device called an aberrometer is focused into spots and recorded by a special camera, the Eye Surgery Education Council states. Both higher-order and low-order aberrations are mapped out by the procedure. Higher-order aberrations, or HOA, are more complex than spherical and cylindrical abnormalities that cause near-sightedness, farsightedness and astigmatism, considered low-order aberrations. All corrective eye surgery procedures tend to worsen HOA, which comprise around 17 percent of optical errors, the Eye Surgery Education Council explains. Wavefront technology may especially benefit people with multiple high-order aberrations that could worsen during refractive surgery. All About Vision reports that contrast sensitivity and night vision significantly improved in several studies after custom LASIK.
Wavefront-Guided Customized LASIK
In Wavefront-Guided Customized LASIK, the information obtained from the diagnostic procedure is transferred to the laser, allowing customization of the laser treatment, sometimes called ablation of the cornea, according to All About Vision. CustomCornea, CustomVue and Zyoptix are all wavefront-guided procedures.
Wavefront-Optomized Procedures
Wavefront optimized procedures such as The Wave Light Allegretto Laser don't utilize a preoperative diagnostic mapping before LASIK. Instead, the patient's eyeglass prescription is used to adjust laser ablation, Refractive Surgery News states. One study conducted by Baylor University found that wavefront-guided customized procedures decreased the number of HOAs after surgery compared to wavefront- optimized procedures. The study reported that 12 percent of patients had an increase in HOAs after wavefront-guided customized surgery, compared to 41 percent with an increase after wavefront-optimized procedures, Refractive Surgery News reported. Outcomes also varied more among people having wave front-optimized procedures than people undergoing customized procedures.
References
- All About Vision; Custom LASIK or Wavefront LASIK: Individualized Vision Correction
- Eye Surgery Education Council: Wavefront Diagnostics & Custom Treatment
- USA Eyes: Wavefront Custom Lasik Laser Eye Surgery
- Refractive Surgery News: Wavefront-GuidedLASIK Induces Fewer Higher-Order Aberrations Than Wavefront-Optimized LASIK
