Most people are unaware of how imperfect the optics of the visual system are in comparison to a a high quality telescope or microscope. Using a physical optics method called "Ray Tracing", we can learn more about how light and vision actually occur. As light rays from distant objects pass through the individual optical components of the eye, they are subject to being distorted by the imperfections found in the cornea and the crystalline lens.

The distortions that are created are referred to as "aberrations." The vast majority--90% or more--of these aberrations create common refractive errors, such as nearsightedness, farsightedness and astigmatism, which can be treated by optical devices, like glasses and contact lenses, or by Laser Eye Surgery, using the traditional methods of LASIK, PRK or LASEK. The remaining 10% of optical aberrations create images which are altered by chromatic aberration, spherical aberration, diffraction, curvature of field, coma, trefoils and quadrafoils--collectively known as "higher order aberrations."
These higher order aberrations only occur in a visually significant manner in 10% to 15% of the general population. When they do occur, they are entirely unique to a particular patient--much like a fingerprint. For  patients with high order aberrations, custom wavefront laser eye surgeryallows the laser eye surgeon to provide a completely customized reshaping of the surface of the cornea which will then correct the higher order aberrations. Custom Laser Eye Surgery requires measuring the higher order optical aberrations using a wavefront analysis system called an aberrometer and then digitally interfacing it with a laser, using high speed computerized control to direct the delivery of a very tiny beam of laser energy across the cornea.
	Aberrometer Wavefront Measurement Systems let the surgeon see aberrations in clear and accurate, rotating 3-D images. by first sending low-energy laser light into the eye. This light reflects off the retina and travels back through the lens and cornea as an outgoing wavefront. This wavefront is captured by the aberrometer, which then measures it to determine both higher and lower order aberrations of the entire optical system of the eye. The aberrations are then displayed on-screen in precise 3-D images.

In order to correct these aberrations we digitally interface that data with the Excimer Laser System using specialized software that is directly guided by the exact shape and depth of the aberrometer measurments that have been taken. This necessitates the use of a high-speed computerized eye tracking method that helps the surgeon enhance the treatment by carefully aligning the laser beam to create a customized ablation and treatment surface.

In addition, since your eyes are continually making very fine jumping movements - called "saccadic" movements which are beyond your control, no matter how hard you concentrate, the Excimer Laser System assists the surgeon by scanning the eye thousands of times per second. Then, using computer control, it makes very fast micro-adjustments to reposition the pinpoint laser beam between pulses of light, tracking even the smallest and quickest movements of your eye during treatment.

In addition, the LADARVision® System uses an ultra-small beam of cool laser light - one that's less than a millimeter wide, a spot much smaller than the thickness of a single human hair. Using high-speed computer control, the LADARVision® System moves this tiny beam of light across the surface of the cornea very rapidly in a tiny, non-sequential and overlapping pattern. This helps the surgeon deliver a smooth customized corneal shape to provide you quick visual recovery and individualized correction of your prescription. Custom Wavefront Guided Laser Eye Surgery is also referred to as Custom Cornea, CustomVue and CustomVision by different LASIK Surgeons.