In a LASIK procedure, the goal is to correct the patient’s vision to the point of not needing glasses or contact lenses. A high percentage of patients achieve this goal; however, official statistics indicate that many are unhappy, and 10% to 20% regress post-operatively and require a second surgical procedure. In some cases the enhancements achieve target refraction but in others the patient cannot be corrected to 20/40 vision. These failures are problems for the refractive surgeon and are often highly publicized by advocacy and watchdog groups such as The Council for Refractive Surgery Quality Assurance.

Currently, no surgeon can scientifically predict or guarantee outcomes; however, some problematic patients can be successfully treated before surgery if they have had their tears analyzed prior to LASIK.

In June 2002, new patient guidelines were introduced by the Eye Surgery Education Council (ESEC) at the annual meeting of the American Society of Cataract and Refractive Surgeons (ASCRS). These guidelines encourage patient-surgeon communication and careful screening of candidates prior to refractive surgery. "These guidelines will help patients understand whether or not LASIK is right for them, what they should expect from their doctor and, ultimately, what to expect from the procedure. As with all surgeries, the decision to undergo laser eye surgery should not be taken lightly," said ESEC Chair Roger Steinert, MD, Associate Clinical Professor of Ophthalmology, Harvard Medical School, Boston, Massachusetts.

Potential patients reading the guidelines are informed they may be an "ideal" LASIK candidate, "less than ideal", or are not a candidate at all. Those with allergic conjunctivitis, dry eye syndrome or corneal scarring discover they are "less than ideal" candidates; however, some learn that they may be able to reconsider LASIK at a later date. The document explains, however, that realistic expectations are essential to patient satisfaction. It notes that while "the overwhelming majority" of patients who have had LASIK surgery are satisfied with their results, patients should be aware of the risks and should make an informed decision based on the facts. The guidelines walk patients through the pre-LASIK screening examination, explaining every aspect of the comprehensive vision exam.

LASIK surgeons (primarily ophthalmologists) understand how tear profiling is able to provide the practitioner with diagnostic as well as prognostic information that may help to minimize and, in some cases, prevent problems from occurring.