Abstract:
Some embodiments disclosed here provide for a method fragmenting a cataractous lens of a patient's eye using an ultra-short pulsed laser. The method can include determining, within a lens of a patient's eye, a high NA zone where a cone angle of a laser beam with a high numerical aperture is not shadowed by the iris, and a low NA zone radially closer to the iris where the cone angle of the laser beam with a low numerical aperture is not shadowed by the iris. Laser lens fragmentation is accomplished by delivering the laser beam with the high numerical aperture to the high NA zone, and the laser beam with the low numerical aperture to the low NA zone. This can result in a more effective fragmentation of a nucleus of the lens without exposing the retina to radiation above safety standards.
Abstract:
Some embodiments disclosed here provide for a method fragmenting a cataractous lens of a patient's eye using an ultra-short pulsed laser. The method can include determining, within a lens of a patient's eye, a high NA zone where a cone angle of a laser beam with a high numerical aperture is not shadowed by the iris, and a low NA zone radially closer to the iris where the cone angle of the laser beam with a low numerical aperture is not shadowed by the iris. Laser lens fragmentation is accomplished by delivering the laser beam with the high numerical aperture to the high NA zone, and the laser beam with the low numerical aperture to the low NA zone. This can result in a more effective fragmentation of a nucleus of the lens without exposing the retina to radiation above safety standards.
Abstract:
Embodiments of this invention generally relate to ophthalmic laser procedures and, more particularly, to systems and methods for photorefractive keratectomy. In an embodiment, an ophthalmic surgical laser system comprises a laser source generating a pulsed laser beam and a laser delivery system delivering the pulsed laser beam to a cornea of an eye. A patient interface couples to and constrains the eye relative to the laser delivery system. A controller controls the laser delivery system to perform an anterior surface volume dissection on the cornea.
Abstract:
Some embodiments disclosed here provide for a method fragmenting a cataractous lens of a patient's eye using an ultra-short pulsed laser. The method can include determining, within a lens of a patient's eye, a high NA zone where a cone angle of a laser beam with a high numerical aperture is not shadowed by the iris, and a low NA zone radially closer to the iris where the cone angle of the laser beam with a low numerical aperture is not shadowed by the iris. Laser lens fragmentation is accomplished by delivering the laser beam with the high numerical aperture to the high NA zone, and the laser beam with the low numerical aperture to the low NA zone. This can result in a more effective fragmentation of a nucleus of the lens without exposing the retina to radiation above safety standards.
Abstract:
The field of the invention relates to systems and methods for ophthalmic laser procedure and, more particularly, to systems and methods for dynamic fixation used in the fixation of the eye(s) of a patient during laser-assisted ophthalmic surgery and/or ophthalmic diagnostic and measurement systems where visualization and concentration on a target are desired. The invention generally enhances the alignment between the eye and a laser beam of a laser eye surgery system using visual fixation system and laser delivery optics. The visual fixation system allows a patient's eye(s) to be accurately focused at one or more fixation targets.
Abstract:
A single-piece patient interface device for coupling a patient's eye to an ophthalmic surgical laser system includes a cone substrate with a rigid frustoconical shaped shell for coupling to the laser system, and a flexible suction ring integrally joined to the lower end of the rigid shell for coupling to the patient's eye. The suction ring has a circular skirt extending downwardly from a base portion, a diaphragm extending from the base portion and disposed inside of the skirt, and a contact lens held by the diaphragm to cover a center opening. When the skirt contacts the eye's surface, the skirt, the diaphragm, the contact lens and the eye surface form a vacuum chamber, where a vacuum may be applied to secure the patient interface device to the eye. The parameters of the suction ring are optimized to fit a large range of eye sizes, including smaller eyes.
Abstract:
In a femtosecond laser eye surgery system where beam delivery is accomplished with a moving objective, a dual-channel imaging system allows real-time procedure visualization before and during incision. The first (docking) imaging channel covers a full field of view (FoV) of the eye, e.g., 13 mm; the second (cutting) imaging channel is through the objective and moves with it, and covers a smaller FoV, e.g., 2 mm. During eye docking and undocking, the objective is moved to a parking position out of the visual field of the docking imaging channel, and the latter operates to provide process visualization. During incision, a composite eye image is displayed, composed of a stationary image captured by the docking imaging channel before treatment began overlayed with live cutting images captured by the cutting imaging channel. The live cutting images are compared to the stationary image in real time to detect eye movement.
Abstract:
An ophthalmic laser surgical system has a built-in imaging sensor for measuring laser focal spot size. An objective lens focuses the laser beam to a focal spot near a reflective surface, scans the focal spot in the depth direction, and focuses light reflected by the reflective surface to form a back-reflected light. A two-dimensional imaging sensor receives a sample of the back-reflected light to generate images of the back-reflected light. During the depth scan, the image contains a well-focused light spot when the laser focal spot is located at a fixed offset distance before the reflective surface, but the light spot in the images is otherwise defocused. The images generated during the scan are analyzed to find the smallest light spot size among the images. The laser focal spot size is then calculated from the smallest light spot size using a magnification factor which is a system constant.
Abstract:
In laser-assisted corneal lenticule extraction procedures, the lenticule incision profile includes anterior and posterior lenticule incisions, with one or more of the following features: plano transition zone outside the optical zone, to improve mating of anterior and posterior incision surfaces after lenticule extraction; shallow arcuate incisions above the anterior incision and near the lenticule edge, to improve surface mating; separate ring cut intersecting the anterior and posterior incisions in the transition zone, to reduce tissue bridges and minimize tear at the lenticule edges and facilitate easy lenticule extraction; larger posterior incision, which includes a pocket zone outside the lenticule edge, for better surface mating and bubble management during cutting; and a separate ring shaped pocket cut intersecting the pocket zone of the posterior incision, for bubble management. An entry cut can intersect either the pocket zone of the posterior incision or an entry extension zone of the anterior incision.
Abstract:
An ophthalmic surgical laser system and method for forming a lenticule in a subject's eye using “fast-scan-slow-sweep” scanning scheme. A high frequency scanner forms a fast scanline, which is placed tangential to a parallel of latitude of the surface of the lenticule and then moved in a slow sweep trajectory along a meridian of longitude of the surface of the lenticule in one sweep. Multiple sweeps are performed along different meridians to form the entire lenticule surface, with the orientation of the scanline rotated between successive sweeps. To reduce acceleration and jerk in the XY stage motion, especially during transition from one sweep to the next, the sweeping speed profile is a sigmoid function.