What causes the scarring after PRK surgery and can anything be done about it?

Scarring or haze after PRK is a rare side effect of this variety of laser vision correction. It is caused by a reaction from the stromal keratocyte cells to the excimer laser application. The cells undergo a process called metaplasia in which they assume scar cell attributes. The resulting haze can cause issues with quality of vision as well as light scatter and sensitivity. The scar tissue can be removed surgically allowing for correction of much of the symptom complex you describe.