PRK or surface laser was the original form of laser eye surgery in the early 1990s. It is still one of the 3 common forms of corrective laser performed today but it's modern form is quite different from its early predecessor. One of the main issues with early PRK was haze or scar formation, particularly in higher corrections. Since the mid 2000s, it has become routine to apply a low dose of an anti-haze agent during surgery. This has meant that haze is a very uncommon problem