• LASIK was developed in the early 1990's. Early on, the instruments performing the procedure, known as Keratomes, made small (7-7.5 mm) flaps. The flaps that were created had significant risks:

• In 1998, a new type of keratome was developed, which allows the creation of large, vertically oriented, flaps (9.5 mm in size). These larger flaps significantly reduced the above risks. The large flaps also enabled the entire cornea to receive laser treatment.

Laser eye surgery has been performed in Canada since 1990. The early lasers utilized one large, fixed beam of laser that was 6 mm in size ("broad beam"). In dim light, (the pupil enlarges in the dark) patients with pupils larger than 6 mm would see simultaneously through "lasered" and "unlasered" cornea. This lead to the "halo" or "ghost image" effect at nighttime noted with these lasers.

In addition, there was no eye tracking system. As a result, small movements of the eye could lead to the laser treatment being poorly centered on the cornea ("decentrations"). This could lead to poor vision quality.

In 1998, a new type of excimer laser technology was developed and Montreal, Canada was one of the first cities in North America where it was assessed.

It was a scanning spot laser, which was also equipped with an infrared eye tracker that monitored and tracked eye movements. The principal feature of this laser was that the scanning spot was able to treat the entire 10 mm of cornea. Now, patients with pupils larger than 6 mm (50% of the population) would receive large area laser treatments and would no longer look simultaneously through treated and untreated cornea.