Abstract: An electrosurgical system including an electrode assembly having two electrodes for use immersed in an electrically conductive fluid has a generator with control circuitry for rapidly reducing the delivered radio frequency output power by at least 50% within at most a few cycles of the peak radio frequency output voltage reaching a predetermined threshold limit. In this way, tissue coagulation can be performed in, for example, saline without significant steam generation. The same peak voltage limitation technique is used in a tissue vaporization or cutting mode to limit the size of the steam pocket at the electrodes and to avoid electrode burning. In a blended mode, the output voltage is alternately limited to a value appropriate for coagulation and a value appropriate for cutting or vaporization.

Abstract: Light is administered during photodynamic therapy (PDT) for an extended period of time at a plurality of sites distributed within the abnormal tissue of a tumor. A clinical study has shown that a substantially greater volume of abnormal tissue in a tumor is destroyed by the extended administration of light therapy from a plurality of probes than would have been expected based upon the teaching of the prior art. In this process, a plurality of light emitting optical fibers or probes are deployed in a spaced-apart array. After a photoreactive agent is absorbed by the abnormal tissue, the light therapy is administered for at least three hours.

Abstract: Optical fiber diffusers for emitting light cylindrically along a length of the fiber diffuser with preselected light intensity distributions along the length of the diffuser. The diffuser portion is defined by forming a Bragg grating in a section of the optical fiber core having a modulated index of refraction which acts to couple light radially out of the fiber along the diffuser section. The intensity distribution of light coupled out of the diffuser section of the fiber is controlled by controlling the profile of the modulated index of refraction, namely the coupling coefficient, along the length of the grating. For photodynamic therapy type II strong Bragg gratings are preferred which give higher intensity output over short distances. Multiple Bragg gratings can be written into a multimode fiber for emission of light at several positions along the fiber.

Abstract: The method, device and system for electrical sealing of a puncture opening in a blood vessel wall. In a first embodiment, a vascular sealing probe has two bipolar electrodes formed thereon, is insertable to a position whereat the bipolar tip is adjacent the blood vessel puncture site to effect electrocauterization or electrocoagulation of the puncture site. In a second embodiment the bipolar vascular sealing probe has a first electrode formed thereon and an electrode-guide wire has the second bipolar electrode formed thereon. The electrode-guide wire is passable through a lumen formed in the probe such that the second electrode on the electrode-guide wire is positioned close enough to the first electrode positioned on the probe to permit electrical current to pass therebetween.

Abstract: A method of selecting laser parameters for performing laser-assisted myocardial revascularization to avoid inducing undesired cardiac arrhythmia without synchronization of delivery of laser energy and the patient's cardiac cycle, the method comprising the steps of minimizing the power level of laser energy used, thereby decreasing the overall trauma to the heart, selecting a pulse frequency as great as possible while avoiding adverse summation effects, selecting a pulse width as wide as possible to prevent excessively high peak powers per pulse and not so wide as to cause undesired thermal damage, selecting an energy flux rate, shaping the front end of each pulse of laser energy to provide efficient, non-explosive TMR channeling, and correcting the selected power level, pulse width, pulse frequency and energy flux rate for mechanical events, including method of access to the heart, position of selected portions of myocardium in the heart, temporal duration of the procedure, natural movement of the heart,

Abstract: In photodynamic diagnosis and photodynamic therapy, the oscillating wavelength of laser light from a light source is fitted to a plurality of different kinds of photosensitizers and exciting conditions thereof. Moreover, diagnosis and treatment are achieved using a single light source. Concurrent diagnosis during treatment is realized as well. A semiconductor laser generates laser light having an oscillating wavelength which is variable and a full width at half maximum which is narrow. A light transmission line guides an irradiated laser light the vicinity of a focus, an image transmission line observes the focus and the periphery thereof, a fluorescence light extracting device extracts only the fluorescence light emitted from a photosensitizer excited by the irradiated laser light, an image-pick-up/analyzing device picks up and analyzes an image of the extracted fluorescence light and an image display device displays the analyzing result.

Abstract: An ophthalmological laser surgery system having a laser, associated elements for delivering an optical beam from the laser to a patient eye location, a control unit for controlling the operation of the system and a system input/output device, is enabled by a patient data card. The data card originally contains both patient background and system control information, which is transferred to the control unit via the input/output device. During system operation, newly generated information, such as laser beam power, is stored in the data card to provide an independent record of the surgical procedure actually performed. After one use, the data card is invalidated to prevent further use.

Abstract: An electrosurgical system including an electrode assembly having two electrodes for use immersed in an electrically conductive fluid has a generator with control circuitry for rapidly reducing the delivered radio frequency output power by at least 50% within at most a few cycles of the peak radio frequency output voltage reaching a predetermined threshold limit. In this way, tissue coagulation can be performed in, for example, saline without significant steam generation. The same peak voltage limitation technique is used in a tissue vaporisation or cutting mode to limit the size of the steam pocket at the electrodes and to avoid electrode burning.

Abstract: A dual wavelength surgical laser system for performing laser surgery on living tissue with a minimum amount of collateral tissue damage is disclosed.

Abstract: A shield is provided to protect the outer portions of the cornea and the under surface of a cap of the cornea during LASIK surgery comprising an annular body with a concave lower surface and a central opening, The central opening is sized to be a little smaller than the outer diameter of the cut made to form the cap. The shield is positioned on the upper surface of the cornea and the folded cap to protect the outer edges thereof from exposure to the ray of the laser.

Abstract: A photon-mediated technique for introducing biological materials into cells and/or cellular components. The technique may be used to introduce nucleic acids, such as DNA and RNA, proteins or other biological materials into mammalian cells (as well as into other animal and plant cells), which materials may then flow into the nuclei of the cells. The technique uses picosecond or femtosecond light pulses propagating in the UV, visible and near infrared wavelength regions with powers on the order of 1×1010 W/cm2. In practice, the desired biological materials are coated on the end of the inner core of a single mode fiber or the ring core of a fiber in a fiber array. Each fiber is sized to correspond to one cell, with the core size ranging from 2&mgr; to 10&mgr;, and the cladding ranging from 10&mgr; to 30&mgr;. The laser pulse travels through a fiber core which is coated with the materials and ablates a portion of a targeted cell or cellular component membrane.

Abstract: A device for eliminating decentration error due to parallax during ophthalmic laser surgery comprises a stereo microscope having a first ocular and a second ocular and an objective lens for viewing a patient's eye, a laser for projecting a laser beam at a patient's eye during ophthalmic laser surgery; and structure for aligning the objective lens relative to the first ocular to center the laser beam with a patient's eye. The device for eliminating decentration error due to parallax also comprises prism positioned between either the first ocular and the objective lens or the objective lens and the laser beam.

Abstract: An apparatus is described for use in combination with a noninvasive ophthalmological method for cornea reshaping in order to correct ocular refractive errors such as myopia (nearsightedness), hyperopia (farsightedness), and astigmatism. This apparatus is called a coupler and it is made of a material which is substantially transparent to the light energy used to reshape the cornea. The coupler conducts heat from the anterior portion of the cornea during the heating of the stroma by the light energy. The reshaping is enhanced by the coupler as it has a corneal engaging surface with a radius of curvature which approximates the desired emmetropic shape of the cornea. In addition to being a heat sink and template for the eye, the coupler also acts as a positioner and restrainer of the eye by attaching itself to the eye via an annular suction ring. Finally, the coupler also acts as a mask to prevent accidental exposure of the central optic zone to any light energy during the cornea reshaping procedure.

Abstract: A laser treatment apparatus for irradiating an affected area of a patient with a treatment laser beam is disclosed. In the apparatus, the treatment laser beam is emitted by a laser source and delivered to the affected area through a treatment laser beam irradiation optical system to irradiate the affected area. An aiming light delivery optical system forms plural aiming light beams so that an optical axis of the treatment laser beam irradiation optical system is put between the aiming light beams, and delivers the plural aiming light beams to the affected area so that the aiming light beams are focused on a position on which the treatment laser beam is to be focused. During this focusing, the aiming beams are being rotated manually or automatically by a manual rotation mechanism or an automatic rotation mechanism. The rotating mode of the aiming beams is selected with a selection switch from a manual rotation mode and an automatic rotation mode.

Abstract: A method for the laser photoablation of ocular lens tissue comprises the steps of determining a volume of the lens tissue to be photoablated and directing a pulsed, infrared laser beam at the volume with an amount of energy effective for photoablating the determined region without causing substantial damage to surrounding tissue regions. The laser beam is initially directed at a focal point below an anterior surface of the ocular lens and such focal point is moved towards the ocular lens anterior surface in order to ablate the determined volume. The laser is preferably an Nd:YLF laser operating at a frequency of about 1053 nanometers and a pulse repetition rate of about 1000 Hertz with a pulse width of about 60 picoseconds. Each pulse has an energy of about 30 microjoules. The laser operates with a focused beam diameter of about 20 microns and operates with a “zone of effect” of no greater than about 50 microns.

Abstract: Systems, methods and apparatus for performing selective ablation of a corneal surface of an eye to effect a desired corneal shape, particularly for correcting a hyperopic/astigmatic condition by laser sculpting the corneal surface to increase its curvature. In one aspect of the invention, a method includes the steps of directing a laser beam onto a corneal surface of an eye, and changing the corneal surface from an initial curvature having hyperopic and astigmatic optical properties to a subsequent curvature having correctively improved optical properties. Thus, the curvature of the anterior corneal surface is increased to correct hyperopia, while cylindrical volumetric sculpting of the corneal tissue is performed to correct the astigmatism. The hyperopic and astigmatic corrections are preferably performed by establishing an optical correction zone on the anterior corneal surface of the eye, and directing a laser beam through a variable aperture element designed to produce a rectangular ablation (i.e.

Abstract: An apparatus and technique for transscleral light-mediated biostimulation of the trabecular plates of a patient's eye in a treatment for glaucoma or ocular hypertension. The apparatus includes; (i) a working end geometry for contacting the anterior surface of the sclera and cornea to insure that a laser emission reaches the trabecular meshwork from a particular location on the anterior surface of the sclera, (ii) a laser energy source providing a wavelength appropriate for absorption beneath the anterior scleral surface to the depth of the trabecular plates, and (iii) a dosimetry control system for controlling the exposure of the laser emission at the particular spatial locations. The device uses a light energy source that emits wavelengths in the near-infrared portion of the spectrum, preferably in the range of about 1.30 &mgr;m to 1.40 &mgr;m or from about 1.55 &mgr;m to 1.85 &mgr;m.

Abstract: An apparatus for corneal surgery to correct a refractive error by ablating corneal tissue with a laser beam emitted from a laser source and delivered onto a cornea of a patient's eye with a light delivering optical system, the apparatus comprising an irradiation area limiting device for limiting an irradiation area of the laser beam and for varying the irradiation area, a first control device for controlling the irradiation area limiting device so as to reduce an ablation amount as the laser beam irradiates further away from a flattest meridian of astigmatism whereby effecting astigmatic correction, a second control device for controlling the irradiation area limiting device so as to increase an ablation amount as the laser beam irradiates further away from a steepest meridian of astigmatism whereby effecting astigmatic correction, and an arithmetic device for dividing a refractive power required for astigmatic correction into halves approximately equally so that an approximately half of the astigmatic c

Abstract: A method and system are provided for sensing eye motion, such as saccadic eye motion, in a non-intrusive fashion. An optical delivery arrangement converts a laser beam pulse into a plurality of light spots. The light spots are focused such that they are incident on a corresponding plurality of positions located on a boundary whose movement is coincident with that of eye motion. The boundary can be defined by two visually adjoining surfaces having different coefficients of reflection. Energy is reflected from each of the positions located on the boundary receiving the light spots. An optical receiving arrangement detects the reflected energy from each of the positions. Changes in reflected energy at one or more of the positions is indicative of eye motion.

Abstract: In a laser treatment apparatus, a treatment laser beam emitted from a laser source 10 is coaxially aligned to an aiming beam emitted from an aiming light source 18 by a beam splitter 20. The coaxial beams are delivered to a patient's eye E through a light delivery optical system, when a controller 60 controls an inclination angle of a filter 57 to change its spectral characteristics such that the filter cuts off the treatment laser beam during the treatment laser irradiation, while allows to the aiming beam to pass during the observation of the patient's eye.