Abstract: A system for treating age-related macular degeneration includes an agent with non-centro symmetric molecules_for marking a region of diseased tissue. An optical assembly focuses the laser beam to a plurality of focal points in the region of diseased tissue, each focal point having a volumetric measurement of about 2 ?m×2 ?m×20 ?m. Due to an increased concentration of photons in the relatively small volume of each focal point, two photons interact with a single molecule of the marking agent, within a very short interval of time (e.g. 10?13 sec). The resultant excited electron state (e.g. 3 eV) is sufficient to induce the marking agent to convert oxygen in a manner that causes the oxygen to kill the diseased tissue. Also, an interaction between photons and a non-centro symmetric molecule in the marking agent will cause a Second Harmonic Generation (SHG) response that can be used for imaging purposes.

Abstract: A system and method for performing ophthalmic surgery requires splitting a laser beam into a pattern having a plurality of focal points. The pattern is then moved along a spiral path according to a predetermined, two-phase protocol. In the first phase, a radial spacing “?r” between spiral lines, and the velocity of the pattern “r?” are held constant as the radius “r” is decreased from r1 to r2. In the second phase the angular velocity “?” is held constant and the radial spacing “?r” is proportionally increased as “r” is further decreased from r2 to r3. Additional LIOB is required both inside r3, as r is reduced to zero and, then, along the periphery of the treatment area for a rim cut at r1.

Abstract: A method and system for customizing a flap created from a transparent material compensates for aberrations, particularly higher order aberrations, which are pre-existing or otherwise induced during creation of the flap. Before flap creation, the distorted wavefront of the transparent material is determined and the topology of the transparent material is defined in order to predict contributions likely to be encountered or induced by the stress distribution during creation of the flap. In view of the topology of the transparent material, a prototypic dissection path based on the distorted wavefront is refined to establish a refined dissection path. As a result, the flap is created along the refined dissection path to correct and minimize or eliminate the formation of higher order aberrations.

Abstract: A device to compensate for asymmetrical aberrations in a beam of light includes at least one dual compensator positioned on the beam path. Structurally, the dual compensator includes two juxtaposed plates, each having a same pattern presented thereon. The patterns, however, are rotated through an angle ? relative to each other. Together, the plates of the dual compensator can then be rotated on the beam path through an angle ? to compensate for asymmetrical aberrations in the light beam. Dual compensators, having appropriate patterns, can be collectively used to compensate for astigmatism, coma and trefoil.

Abstract: A system and method for performing ophthalmic laser surgery requires directing a laser beam through a stationary beam splitter to create a pattern of multi-focal spots. Also, a beam scanner is used to move this pattern along a substantially spiral path in a target area of tissue. To compensate for cyclical changes in orientation of the pattern relative to its spiral path, a computer is used to phase modulate pattern movement. Specifically, this phase modulation is expressed as: v?=v(1+F sin(n?)) where v is a variable (e.g. angular speed, line spacing, or z-spacing), v? is the phase modulated variable, F is a magnitude factor for phase modulation control, n is an integer, and ? is an angular position of the pattern during phase modulation.

Abstract: A system for treating age-related macular degeneration includes an agent for marking a region of diseased tissue. Additionally, the system includes a femtosecond laser source for generating a laser beam. Further, an optical assembly focuses the laser beam to a plurality of focal points in the region of diseased tissue, each focal point having a volumetric measurement of about 2 ?m×2 ?m×20 ?m. Due to an increased concentration of photons in the relatively small volume of each focal point, two photons interact with a single molecule of the marking agent, within a very short interval of time (e.g. 10?13 sec). The resultant excited electron state (e.g. 3 eV) is sufficient to induce the marking agent to convert oxygen in a manner that causes the oxygen to kill the diseased tissue.

Abstract: A system and method for performing ophthalmic surgery requires splitting a laser beam into a pattern having a plurality of focal points. The pattern is then moved along a spiral path according to a predetermined, two-phase protocol. In the first phase, a radial spacing “?r” between spiral lines, and the velocity of the pattern “r?” are held constant as the radius “r” is decreased from r1 to r2. In the second phase the angular velocity “?” is held constant and the radial spacing “?r” is proportionally increased as “r” is further decreased from r2 to r3. Additional LIOB is required both inside r3, as r is reduced to zero and, then, along the periphery of the treatment area for a rim cut at r1.

Abstract: A closed-loop control system for altering the optical characteristics of a patient's cornea includes an algorithm for predicting the shape of the cornea after one or more gas bubbles resulting from intrastromal photoablation have collapsed. Patient data can be used as an input for the algorithm, which is then run to prepare an initial treatment plan for a corneal alteration. The initial plan typically includes a plurality of intrastromal photoablation locations and corresponding ablation energies. After photoablation of plan location(s) and before the resulting bubbles collapse, a real-time wavefront shape for light passing through the cornea is measured. The wavefront is then used in the algorithm to predict a post bubble collapse cornea shape and to generate an updated treatment plan. The procedure then continues by ablating location(s) identified in the updated treatment plan. Wavefront measurement and plan updating can be repeated as many times as desired.

Abstract: A device to compensate for asymmetrical aberrations in a beam of light includes at least one dual compensator positioned on the beam path. Structurally, the dual compensator includes two juxtaposed plates, each having a same pattern presented thereon. The patterns, however, are rotated through an angle ? relative to each other. Together, the plates of the dual compensator can then be rotated on the beam path through an angle ? to compensate for asymmetrical aberrations in the light beam. Dual compensators, having appropriate patterns, can be collectively used to compensate for astigmatism, coma and trefoil.

Abstract: A method and apparatus for intrastromal refractive surgery is disclosed wherein tissue at selected locations within the stroma of the cornea is photoablated using a pulsed laser beam. The apparatus includes an optical system for forming a shaped laser beam having a waist at a predetermined distance from the optical system. The pulse duration and pulse energy of the laser beam are selected to cause ablation to occur in front of the waist (i.e. between the waist and the optical system). To achieve this, a pulse energy is used that exceeds the minimum pulse energy required for ablation at the waist. By ablating in front of the waist, a relatively large ablation zone (per pulse) is created (compared to ablation at the waist). Furthermore, while the laser is scanned through the cornea to effectuate a refractive change, the optical system maintains a uniform waist for the laser beam.

Abstract: A method and system for customizing a flap created from a transparent material compensates for aberrations, particularly higher order aberrations, which are pre-existing or otherwise induced during creation of the flap. Before flap creation, the distorted wavefront of the transparent material is determined and the topology of the transparent material is defined in order to predict contributions likely to be encountered or induced by the stress distribution during creation of the flap. In view of the topology of the transparent material, a prototypic dissection path based on the distorted wavefront is refined to establish a refined dissection path. As a result, the flap is created along the refined dissection path to correct and minimize or eliminate the formation of higher order aberrations.

Abstract: A system for spatially stabilizing a base point on the optical axis of a patient's eye, for photoablation of the cornea, includes an optical element for identifying the base point. The system also includes an illumination source which is a fixation point for the eye. Movement of the illumination source induces a saccadic movement of the eye wherein the optical axis of the eye moves from a first orientation to a second orientation. Following the saccadic movement of the eye there is a latency period during which the base point, and hence the eye, is substantially stabilized. Movement of the light source is timed to coincide the latency period with the resting period of the patient's heartbeat sequence, and the relaxation period of the patient's respiration cycle. During the latency period, photoablation is accomplished by directing a train of laser pulses from a laser source into the corneal tissue.

Abstract: A closed-loop control system for altering the optical characteristics of a patient's cornea includes an algorithm for predicting the shape of the cornea after one or more gas bubbles resulting from intrastromal photoablation have collapsed. Patient data can be used as an input for the algorithm, which is then run to prepare an initial treatment plan for a corneal alteration. The initial plan typically includes a plurality of intrastromal photoablation locations and corresponding ablation energies. After photoablation of plan location(s) and before the resulting bubbles collapse, a real-time wavefront shape for light passing through the cornea is measured. The wavefront is then used in the algorithm to predict a post bubble collapse cornea shape and to generate an updated treatment plan. The procedure then continues by ablating location(s) identified in the updated treatment plan. Wavefront measurement and plan updating can be repeated as many times as desired.

Abstract: A system for spatially stabilizing a base point on the optical axis of a patient's eye, for photoablation of the cornea, includes an optical element for identifying the base point. The system also includes an illumination source which is a fixation point for the eye. Movement of the illumination source induces a saccadic movement of the eye wherein the optical axis of the eye moves from a first orientation to a second orientation. Following the saccadic movement of the eye there is a latency period during which the base point, and hence the eye, is substantially stabilized. Movement of the light source is timed to coincide the latency period with the resting period of the patient's heartbeat sequence, and the relaxation period of the patient's respiration cycle. During the latency period, photoablation is accomplished by directing a train of laser pulses from a laser source into the corneal tissue.

Abstract: A system for diagnostically evaluating the health of tissue within the fundus of an eye includes a f s laser source, an adaptive optical assembly, an imaging unit, and a computer. The adaptive optical assembly focuses a laser beam to a focal point in the fundus of the eye, and scans the fundus tissue according to a predetermined scanning pattern. Illumination of anisotropic tissue within the fundus, such as the photoreceptors and the Henle-fiber layer, induces a Second Harmonic Generation (SHG) response. Red photons, with a wavelength (?) of about 880 nm, are converted to blue photons, with a wavelength of ?/2, through the process of photon conversion. An imaging unit senses the blue photon return light, and uses the return light to generate an image of the fundus. The computer processes the image, and compares it to a template of healthy tissue to evaluate the health of the imaged tissue.

Abstract: Apparatuses and methods for improving aberration determination capabilities, providing corrective prescription verification, and allowing binocular vision correction in ophthalmic wavefront measuring devices. (1) Improved aberration determination capabilities are achieved through input beam modification which includes sensing an image in a wavefront emanating from an eye in response to an input beam with a sensor and then modifying the input beam with an adaptive optical device based on the sensed information. (2) Corrective prescription verification includes modifying an image with an adaptive optical element to produce a corrected image at the patients eye. (3) Binocular vision correction for a pair of eyes includes measuring the aberrations of one eye with a first ophthalmic wavefront measuring device and measuring the aberration produced by the other eye with a second ophthalmic wavefront measuring device substantially simultaneously.

Abstract: A closed-loop control system for the intrastromal photoablation of tissue includes an active mirror for individually directing the component beams of a diagnostic laser beam to a focal point on the retina of an eye. The reflected beam is analyzed to identify a distorted wavefront indicative of required corneal corrections, and an induced wavefront indicative of optical aberrations introduced by bubbles formed during tissue ablation. A comparator alters the induced wavefront with a desired wavefront to create a rectified wavefront, and a comparator compares the rectified wavefront with the distorted wavefront to create error signals. The error signals are then used to operate the active mirror and to control an ablation laser until the absence of error signals indicate the required stromal tissue has been photoablated.

Abstract: Apparatuses and methods for improving aberration determination capabilities, providing corrective prescription verification, and allowing binocular vision correction in ophthalmic wavefront measuring devices. (1) Improved aberration determination capabilities are achieved through input beam modification which includes sensing an image in a wavefront emanating from an eye in response to an input beam with a sensor and then modifying the input beam with an adaptive optical device based on the sensed information. (2) Corrective prescription verification includes modifying an image with an adaptive optical element to produce a corrected image at the patients eye. (3) Binocular vision correction for a pair of eyes includes measuring the aberrations of one eye with a first ophthalmic wavefront measuring device and measuring the aberration produced by the other eye with a second ophthalmic wavefront measuring device substantially simultaneously.

Abstract: Defocus and astigmatism compensation methods and apparatuses for use in an aberration measurement system. The apparatuses including reflectors for altering the optical distance between a pair of lenses passing a wavefront without changing the physical distance between the lenses, thereby compensating for defocus in the wavefront; and cylindrical mirrors for adding and removing curvature from a curved wavefront, thereby compensating for astigmatism in the wavefront. The methods including passing a wavefront having defocus through a first lens on a first path, reflecting the wavefront from the first path to a second path, reflecting the wavefront from the second path to a third path, and passing the wavefront through a second lens as a defocus compensated wavefront; and passing a wavefront through first and second cylindrical lens, and orienting the first and second cylindrical lenses with respect to the wavefront and to one another to compensate for astigmatism in the wavefront.

Abstract: A closed-loop control system for the intrastromal photoablation of tissue includes an active mirror for individually directing the component beams of a diagnostic laser beam to a focal point on the retina of an eye. The reflected beam is analyzed to identify a distorted wavefront indicative of required corneal corrections, and an induced wavefront indicative of optical aberrations introduced by bubbles formed during tissue ablation. A comparator alters the induced wavefront with a desired wavefront to create a rectified wavefront, and a comparator compares the rectified wavefront with the distorted wavefront to create error signals. The error signals are then used to operate the active mirror and to control an ablation laser until the absence of error signals indicate the required stromal tissue has been photoablated.