Traditional treatment involves taking your eyeglasses prescription and plugging it into the laser. If 5 people have a -3.00 prescription, the same information will be fed to the laser not taking into account other visual aberrations in their eye. Custom treatment (such as iLASIK/Wavefront or Zyoptix) draws its data from an aberrometer measurement. This information is very different from one person to another even if they have the same prescription. It is, therefore “customized. Many studies have shown that custom treatments will lead to a better chance of 20/20 vision and less negative symptoms at night such as halos around light. Our own results are consistent with these findings.