Abstract

A method and apparatus for modifiying corneal refractive properties includes a laser source, computer control, and a plurality of deflectors including at least one rotating and translating deflector. A beam emitted from the laser source is deflected by the rotating and translating deflector in a controlled manner such that the beam strikes the cornea tangentially, ablating or lathing the contacted surface. The apparatus is computer controlled to intra-operatively determine the visual axis, monitor fixation, monitor changing refractive error, adjust the rotating and translating deflector and activate and deactivate the laser. The invention allows the radius of curvature of the cornea to be modified in vivo or in vitro. The cornea is lathed tangentially in either a natural or frozen state in an area centered about its optical axis, encompassing its optical zone. In one embodiment, a rotating arm, rotating in a plane perpendicular to the optical axis of the cornea, transmits the laser beam to the variable deflector.

Other References

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