System and method for locating a surface of ocular tissue for glaucoma surgery based on dual aiming beams

A system for locating a target surface of ocular tissue in an irido-corneal angle of an eye for photodisruption by a laser, the system comprising:

• a laser source configured to output a laser beam;
• a dual aiming beam apparatus configured to transmit a first aiming beam of light and a second aiming beam of light;
• an OCT imaging apparatus configured to output an OCT beam and optically aligned to capture one or more OCT images of the irido-corneal angle;
• an optics subsystem optically aligned with the laser source, the dual aiming beam apparatus, and the OCT imaging apparatus to receive the laser beam, the first aiming beam of light, the second aiming beam of light, and the OCT beam, the optics subsystem comprising a focusing objective configured to:
• direct the laser beam, the first aiming beam of light, the second aiming beam of light, and the OCT beam along an angled beam path through a cornea and an anterior chamber of the eye, to be incident with the target surface of ocular tissue in the irido-corneal angle of the eye, and
• align the first aiming beam of light, the second aiming beam of light and the OCT beam relative to each other and relative to the laser beam such that the first aiming beam of light, the second aiming beam of light, and the OCT beam intersect at a point corresponding to a focus of the laser beam;
• and
• an imaging apparatus optically aligned with the optics subsystem to capture an image of the irido-corneal angle including a first spot corresponding to the first aiming beam of light and a second spot corresponding to a second aiming beam of light.

A method of locating a target surface of ocular tissue in an irido-corneal angle of an eye for photodisruption by a laser, the method comprising:

• directing a laser beam, an OCT beam, a first aiming beam of light, and a second aiming beam of light along an angled beam path through a cornea and an anterior chamber of the eye, to be incident with the target surface of ocular tissue in the irido-corneal angle of the eye, wherein the OCT beam, the first aiming beam of light and the second aiming beam of light are aligned relative to each other and relative to a laser beam such that the OCT beam, the first aiming beam of light and the second aiming beam of light intersect at a point corresponding to a focus of the laser beam;
• capturing an image of a first spot corresponding to the first aiming beam of light and a second spot corresponding to a second aiming beam of light;
• and
• capturing one or more OCT images of the irido-corneal angle.