Device and method for performing refractive surgery

A method for photodisrupting lamellae in the stroma of an eye, said method comprising the steps of:

• focusing a laser beam to a focal point at a first location in the stroma to photodisrupt stromal tissue and create a photodisruptive response thereto, said photodisruptive response being indicative of a diameter of a gas bubble created in the stroma during photodisruption;
• comparing said photodisruptive response to a reference value;
• and
• selecting a second location for photodisruption, said second location being at approximately the same depth from the anterior surface of the cornea as said first location when said photodisruptive response is less than said reference value and said second location being at a different depth from the anterior surface of the cornea than said first location when said photodisruptive response is greater than said reference value.

A method for photodisrupting stromal lamellae within the cornea of an eye to alter the refractive properties of the cornea, said method comprising the steps of:

• focusing a laser beam to a focal point in the stroma to photodisrupt stromal tissue and create a gas bubble in response thereto, 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 photodisruption;
• and
• moving said focal point of said laser beam to said selected subsequent location to photodisrupt stromal tissue and create a gas bubble in response thereto to alter the refractive properties of the cornea.