Patent ID: 7101364

Claim:
A method for photoablating stromal tissue, said method comprising the steps of: providing an optical system; using said optical system to form a shaped laser beam along a beam path, said laser beam having a waist at a predetermined distance along said beam path from said optical system; directing said laser beam to position said targeted tissue for ablation along said beam path and to position said waist at non-targeted tissue; controlling the pulse duration and pulse energy of said laser beam to create an ablation zone along said beam path between said waist and said optical system to photoablate said targeted tissue at said ablation zone while preserving said non-targeted tissue at said waist and to produce a gas bubble in response to photoablation of said stromal tissue at said ablation zone, said gas bubble having a diameter; comparing said diameter of said gas bubble to a reference value to determine whether said gas bubble is inside a stromal lamella; using said comparing step to select a subsequent location inside a stromal lamella for photoablation: moving said waist of said laser beam to ablate stromal tissue at said selected subsequent location; and repeating said directing step and said controlling step to successively reposition said waist at a selected variable distance from a previous waist position.