Abstract: A method and apparatus for providing more precise aiming by an eye tracking system, including a registration, or aiming, laser, that provides for precise location of where the next laser ablation shot will impinge upon the eye. The method and apparatus further includes an aiming assistance fixture that provides a fixed frame of reference for locating the origin of the eye.

Abstract: Materials and methods for photoreactive suturing of biological tissue are disclosed. The suture material includes a structure adapted for positioning at an anastomotic site and has at least a portion of the structure formed by a photoreactive crosslinking agent, such that upon irradiation of the structure the crosslinking agent adheres to the biological material. In one embodiment, the suture material can also include a high tensile strength element which is coated with a laser activatable crosslinking agent or glue. The suture methods can be practiced manually, or with various apparatus, such as endoscopes, catheters or hand-held instruments.

Abstract: The method for intra-operative myocardial revascularization of a human heart includes a inserting a portion of an elongated flexible lasing apparatus into the chest cavity of a patient, and lasing channels from the epicardium through the myocardium of the heart, without mechanical tearing of the heart tissue. The apparatus is guided to an area exterior to a ventricle of the patient's heart, and the distal end of the optical fiber apparatus is directed to an area of interest where the exterior wall of the heart is irradiated with laser energy to form a channel through the myocardium.

Abstract: A method for performing a trabeculodissection comprising the steps of forming a scleral flap, determining the treatment arc of tissue located under the scleral flap, designating a number of discrete test areas along the treatment arc under the scleral flap, performing test ablations within the discrete test areas with a galvanometric scanning laser delivery system, determing the discrete treatment zones corresponding to the test areas, programming the galvanometric scanning laser delivery system based upon the results of the test ablations, ablating the tissue, and repairing the sclearal flap.

Abstract: An apparatus for laser surgery on a cornea for correcting the refractive error of a patient's eye by removing away a part of the cornea by a laser beam.

Abstract: A method is provided for facilitating the atrophying of a tonsil or adenoid ("organ") to cause the gradual removal thereof from the patient. A laser is positioned adjacent the organ, the wavelength for the laser being in the 700 nm to 1100 nm range and having energy sufficient to cause coagulation of blood in at least a significant number of the organ vessels over a period of several minutes, but not so much energy as to kill significant tissue of the organ or to cause significant damage to tissue adjacent to the organ. The laser is then turned on to irradiate the organ with laser energy and the entire exposed area of the organ is painted or otherwise irradiated. Irradiation continues until a selected condition of the organ, tissue adjacent the organ and/or laser source occurs.

Abstract: Accurate, non-mechanical removal of the epithelium from essentially only the area of the cornea to be treated. In particular, an epithelium-ablative laser device irradiates the selected region of the epithelium with ablative laser energy, a spectroscopic system monitors the ablation and spectroscopically determines whether epithelium is being ablated, and a control system terminates the epithelium removal upon spectroscopic determination of a substantial absence of epithelium ablation.

Abstract: A laser operation and control system preferably comprising a laser adapted to be grasped by a user and freely passed over a treatment area, control circuitry for activating and deactivating the laser, at least one boundary sensor operable to transmit a signal to the control circuitry to deactivate the laser upon passage thereof beyond a boundary of the treatment area and to transmit a signal to the control circuitry to activate the laser upon passage thereof within the boundary, and at least one proximity sensor for transmitting a signal to the control circuitry to deactivate the laser should the proximity sensor fail to sense a substantially solid surface within a predetermined distance therefrom and for transmitting a signal to the control circuitry to activate the laser should the proximity sensor sense such a surface.

Abstract: An apparatus and method for controlling the current delivered to a flash lamp is disclosed. The apparatus and method is particularly useful for controlling the current delivered to a flash lamp used in a laser and most particularly useful in connection with lasers used for medical procedures. The apparatus controls the length of the electrical pulse which is delivered to the flash lamp and also limits the current which passes through the flash lamp to that which is desired for optimized operation. A semiconductor switch electrically connects and disconnects the flash lamp from one or more capacitors for the desired length of time. The length of time can be automatically adjusted to provide the desired flash lamp output and thus the desired laser output. The switch provides substantially a square wave having a plateau voltage with very fast rise and fall times on both sides of the plateau so that a suitable square wave is formed.

Abstract: The surgical instrument apparatus emits a narrow beam of light that exits a point on the blade. The light crosses in front of the blade at a point predetermined by the surgeon. The light is reflected off the Descemet's membrane when the tip of the blade reaches the proper depth and bounces back into an entrance point on the blade. The reflected light is received by a light sensor that is coupled to a transmitter. The transmitter sends a signal to a receiver coupled to a tone generator. When the tone is generated, the surgeon knows that the incision has reached the proper depth.

Abstract: A system for welding tissue by irradiation with laser energy, includes a laser for generating a beam of laser energy and directing the beam toward the tissue so as to irradiate the region to be welded. The laser has a control input and is responsive to a control signal supplied to said control input to adjust the power of the beam of laser energy. An infrared sensor senses the temperature of the tissue in the region to be welded by sensing infrared radiation coming from this region. The sensor provides a sensor output indicative of the temperature. A computer control arrangement is responsive to the sensor output. The computer control arrangement supplies a control signal to said laser such that the region to be welded is heated to a predetermined temperature.

Abstract: Methods and apparatus are disclosed for the correction of presbyopia by reprofiling the cornea to create at least one region having a different focal point, and thereby assist the eye in accommodating for close-viewing conditions. According to the invention, at least one region of different curvature is created by photoablation of the cornea to permit the eye to accommodate for near objects. This "add" region is preferably located near the center of the optical zone and preferably within Bowman's membrane or the adjacent upper portions of the stroma, which lies directly below Bowman's membrane. Apparatus is disclosed, including a laser means and a beam-shaping means, disposed between the laser means and the surface of the cornea, which imposes a defined ablation profile upon the cornea. The system can also include a feedback control means for measuring the effectiveness of the laser during operation and for controlling the laser. The beam-shaping means can include either an aperture e.g.

Abstract: An intracavity modulated pulsed laser comprising an amplification medium, a pulsed pumping source, a beam modulator, and two mirrors, one totally reflective and one partially reflective for generating at least one laser output burst comprising a plurality of sub-pulses having variably controllable peak powers.

Abstract: A laser device is provided for the co-axial positioning of plural laser beams of same or different wavelengths along a single axis. At least two laser oscillators are provided, each producing a laser beam. A rotary reflector is positioned for intercepting at least one of the produced laser beams and directing the intercepted laser beam separately from, but along a single axis defined by another laser beam.

Abstract: A laser diode operating system utilizes the photodiode mounted in the housing of the laser diode, and monitors the photodiode signal to check for a clear laser beam delivery path and a target proximate to the output of the beam path. Upon initial power-up of the system, a brief laser pulse is emitted, and laser light reflected retrograde in the delivery path is received by the photodiode. If the photodiode signal exceeds a first threshold level, due to occlusion of the delivery path, further operation of the system is prevented until the delivery path is cleared. During operator use, the photodiode signal is compared with a second threshold level, and operation is interrupted if the signal fails to exceed the second threshold level. During interruption of operation mode, the laser diode is pulsed briefly and reiteratively to ascertain if a target object is proximate to the laser diode output.

Abstract: A catheter having an ultrasound transducer and associated electrically wiring conducted through a sidewall thereof and a plurality of optical fibers provided in the lumen of the catheter for conveying laser light from an external laser source to the tip of the catheter. The laser irradiation is angularly emitted from the tip of each optical fiber. The ultrasound and the laser are connected to a computer system which is used to display ultrasonic images of internal tissue areas within the patient's body and control firing of the laser in response to delimiting input from the physician.

Abstract: A laser heating system projects a beam of optical radiation on a region to be heated. A sensor detects changes in temperature of the region by sensing the black body radiation of the heated region. A control circuit then controls the intensity of the beam as a function of the sensed black body radiation. In another embodiment, the beam is moved among the region and the light intensity of the beam is dynamically controlled.

Abstract: An improved configuration for a surgical laser instrument to provide the alternate contact cutting and no-contact coagulating of biological tissues by means of a fiber-optically guided irradiation of a laser is disclosed. This configuration includes instrumentation to enable discrimination between background illumination (i.e. xenon illumination scopes, room lights) and white light produced by the burning of tissue residue at the distal fiber tip. White light is described as a light having a wavelength between 0.3 to 0.9 mm. This improvement has the advantages of preventing background illumination from interfering with operation of a laser equipped with a white light feedback control device. Ultimately, this provides the surgeon with a more predictable laser delivery device which subsequently makes the laser safer to use.

Abstract: A method of ablating atherosclerotic plaque by means of short-duration laser light pulses. A carotenoid, such as beta-carotene, is preferably administered to the patient by injection or ingestion prior to exposing the plaque with laser light. Research data obtained by analysis of the absorption characteristics of plaque and the healthy arterial tissue reveals that the plaque may be selectively ablated without damaging the surrounding normal tissue by illuminating the plaque with laser light having a wavelength of about 430 to about 510 nanometers such that the relative absorption coefficient exhibited by the plaque is more than 1.5 times the absorption coefficient of the arterial tissue. Short duration laser light pulses preferably illuminate the plaque for less than the thermal relaxation time of the volume of exposed material. The intensity of the laser light is preferably in the range from about 1 to about 9 joules/cm.sup.2 in order to ablate the plaque without endangering the surrounding tissue.

Abstract: An apparatus for optical treatment using a light beam, which includes an apparatus body having a first control operation device for providing an optical treatment light and an optical fiber cable for introducing an optical treatment light from the apparatus body into a delivery unit. The apparatus comprises a light relaying device connected with both of the apparatus body and the delivery unit through the optical fiber cable, second control operation device provided in the light relaying device, optical communication device for transmitting and receiving light signals, the optical communication device being arranged in the apparatus body and the light relaying device respectively, an optical system for introducing the light signals which the optical communication device transmits and receives through the optical fiber cable.

Abstract: The invention relates to a process of treatment in the field of dermatology, for the treatment of cutaneous angio dysplasias, using the energy emitted by a laser source, as well as to an apparatus for the treatment of skin angiomas implementing the process. The apparatus includes a laser source suitable for supplying laser radiation, a treatment instrument for receiving the laser radiation from the source and whereby a plurality of consecutive laser shots is effected to form a plurality of resulting impacts on the area of the body to be treated. Following each shot, the area of the body thus treated has, at the resulting impact, at least a given relaxation time. The apparatus includes a support frame, an optical fiber disposed in the frame. The optical fiber has two ends, the first of the ends being suitable for connection to the laser source via the connecting means, the second end being mobile and suitable for generating a displaceable laser spot.

Abstract: A system for welding tissue by irradiation with laser energy, includes a laser for generating a beam of laser energy and directing the beam toward the tissue so as to irradiate the region to be welded. The laser has a control input and is responsive to a control signal supplied to said control input to adjust the power of the beam of laser energy. An infrared sensor senses the temperature of the tissue in the region to be welded by sensing infrared radiation coming from this region. The sensor provides a sensor output indicative of the temperature. A computer control arrangement is responsive to the sensor output. The computer control arrangement supplies a control signal to said laser such that the region to be welded is heated to a predetermined temperature.

Abstract: The invention concerns a device for correcting the shape of an object by laser treatment.The device comprises means (1) for emitting a laser beam (FL) and means (2) for generating a treatment laser beam (FLT) comprising at least one lobe of elongate cross-section. Means (3) enable focussing of the image of the lobe or lobes of the treatment laser beam on the area of the object (OE) to be corrected and means (4) enable displacement of the image of the lobe of the treatment laser beam in translation or in rotation over the area of the object to be corrected. The total correction or ablation is effected by the summation of a plurality of elementary discrete ablations.Application to refractive surgery in the case of keratomileusis for myopia, hypermetropia or astigmatism, and to shaping contact lenses and intra-ocular implants.

Abstract: An angioplasty system and method for identification and laser ablation of atherosclerotic plaque at a target site in a blood vessel includes fluorescence analysis for identification of noncalcified plaque and calcium photoemission analysis for identification of calcified plaque. Calcified plaque is identified by time domain analysis of calcium photoemission. A high energy pulsed ultraviolet laser can be used for stimulation of fluorescence and for stimulation of calcium photoemission. The system is capable of distinguishing between calcium photoemission and a defective condition of optical fibers that are used to deliver laser energy to the target site. In an another embodiment of the angioplasty system, calcium photoemission is identified during a nonablative initial portion of the laser ablation pulse. When calcium photoemission is not identified, the laser ablation pulse is terminated during the initial nonablative portion thereof.

Abstract: A laser for medical includes an optically pumped laser medium, and the output of the laser is directed through an optical fiber delivery system to a tissue target. The flashlamp is driven by a pulsed power signal that is selectively variable to produce laser pulses of predetermined temporal width and pulse energy, and these values can be selected in accordance with the type of tissue being treated and the tissue effect desired. The laser may be operated to produce relatively brief pulses of high energy, which create a localized plasma at the surface of the target tissue. The plasma effect blocks any significant penetration of the laser beam into the tissue, and each laser pulse causes the ablation of a small portion of the tissue target. Thus thermal necrosis of adjacent and underlying tissue minimized.

Abstract: A coupler for efficiently coupling a laser light source to a fiberoptic catheter. The coupler contains coding for determining information about the catheter, such as the size of the optical fiber catheter which it is coupling.

Abstract: A laser system applies energy of the proper wavelength to the cornea of the eye and the stroma of the cornea is thereby heated and changes permanently, causing the shape of the cornea to change. Laser treatment patterns are disclosed for correcting nearsightedness, farsightedness and astigmatisms.

Abstract: A proximity sensor apparatus for use with a laser diode device utilizes the photodiode mounted in the housing of the laser diode, and includes an electronic circuit coupled to the photodiode to monitor the output of the photodiode. When an object is closely adjacent to the output window of the laser diode, reflected light from the laser diode is transmitted retrograde through the output window and is received by the photodiode within the housing. The circuit of the invention establishes a threshold level for the photodiode current, determines the proximity of the reflecting object and permits (or prevents) operation of the laser diode. The circuit also includes a sampling timer to operate the laser diode for a very brief period (on the order of microseconds) each second, to ascertain if a target object is proximate to the laser diode output. The circuit is set to prevent laser operation, and operates the laser diode to emit a brief test pulse and determine the level of reflected laser light.

Abstract: An instrument for ophthalmic surgery to remove cataractous-lens tissue has an elongate stem which enables external manipulation at its proximal end and which at its distal end presents a cutter adjacent a transiently open cavity into which cut or chopped tissue can be manipulated. The instrument provides for selectively operated closure of the thus-loaded cavity, an event which must occur before laser radiation can issue within the cavity, in fragmenting or emulsifying reduction of cut or chopped tissue within the cavity. Thus, reduced, the fragmented material is extracted by an aspirating flow of liquid. This process is repeated until the capsulary bag has been cleared of cataractous material, be it nuclear or cortical.

Abstract: Apparatus for use in removing atherosclerotic plaque deposits in a blood vessel comprises a high power laser, an elongated, flexible catheter adapted to be inserted into and advanced through the blood vessel, a plurality of circumferentially arrayed optical fibers extending axially through the catheter, and an ultrasonic transducer at the distal end of the catheter for transmitting acoustical energy toward a selected area of the inner surface of a blood vessel in response to laser energy coupled through any one of the optical fibers and impinging upon the transducer. A detector proximal of the ultrasonic transducer is responsive to ultrasonic energy reflected from the blood vessel and produces a signal indicative of the tissue interfaces of the blood vessel. Laser energy can be transmitted from the high power laser through the same optical fiber used for the diagnostic procedure to ablate plaque in the blood vessel.

Abstract: An instrument for and method of effectively treating the prostatic urethra so as to relieve the symptoms associated with an enlarged urethra is disclosed. The tissue of at least selected portions of the prostate are compressed (preferably with a balloon inserted into the prostatic urethra so as to enhance hemostasis) and at least selected portions of the compressed tissue are directly irradiated (preferably with a laser beam transmitted from within the passageway in selected radial directions and moved along the prostatic urethra while exposing the tissue) so as to cause coagulation necrosis of selected portions of the compressed tissue so that as the tissue heals, the necrosed tissue slowly sloughs off during normal urination through the urinary tract so as to effectively remove the constricted portions of the prostatic urethra. Ultrasonic transducers are used from within the prostatic urethra to image the tissue as it is irradiated so as to monitor the procedure to insure proper exposure to the laser beam.

Abstract: The invention contemplates controlled ablation of the cornea, using ultraviolet laser radiation, wherein irradiated flux density and exposure time are so controlled as to achieve desired depth of the ablation. Sculpturing action results from precharacterized distribution of flux density across the cross-section of laser-beam projection, in the context of beam size, at cornea incidence, to match the area to be ablated, and the duration of exposure determines the extent of curvature change. Illustrative techniques and situations are disclosed, for myopia correction, for hyperopia correction, and for astigmatism correction.

Abstract: A proximity detector for the probe of a beam delivery apparatus of a laser system includes a probe having a face for confronting a target surface to be struck by the laser beam; means for directing a gauging light to the target surface; means for sensing the gauging light returning from the target surface to the probe; and means responsive to the means for sensing for generating a control signal representative of the position of the probe relative to the surface to enable the laser system to fire.

Abstract: Methods and apparatus for determining the depth of excision generated by a material removal process, for determining the thickness of unablated material below the excision or incision, and for providing endpoint control of a material removal process utilize acoustic transducers for measuring the time delay between a first acoustic pulse resulting from material removal and a second acoustic pulse reflected from a distal surface or boundary layer of the material. The time delay between the two pulses detected by the transducer provides a measure of excision depth and of the depth of material below the excision. Endpoint control is provided by terminating material removal when a selected excision depth is detected. The invention can be used, for example, as a real-time monitor of excision depth and residual lamella thickness under the excision during laser corneal surgery.

Abstract: Apparatus for selective destruction or inactivation of cells is disclosed wherein cells are arrayed in a plane for successive illumination, by optical X-Y scanning devices, with a first low powered light beam to produce in particular cells certain radiations responsive to the illumination. These response radiations are detected and used to enable a second higher powered light beam directed through substantially the same optical scanning paths, to destroy or inactivate the cells producing the response radiations. The illumination, response, detection, and high power radiation steps are accomplished by devices acting in times short as compared to the X-Y scanning devices so as to make the accurate treatment of each of large numbers of cells highly effective.

Abstract: The multiple optical fiber event sensor apparatus includes a semipermeable generally cylindrical shaft, one or more optical fiber gas sensor modules within the shaft, and an optical fiber pH sensor module extending beyond the distal end of the shaft, with the sensor modules arranged in an axially staggered relationship. The shaft contains a potting matrix for axially fixing the position of the optical fibers, and includes a gas permeable portion surrounding the one or more gas sensor modules, and a hydrophilic portion covering at least part of the pH sensor module. A hemodynamically shaped, rounded distal end is also provided on the distal end of the shaft. The device provides for a multiplicity of individual sensors incorporated in a single shaft which minimizes cross-interference and thrombus formation when used as an intravascular multi-sensor.

Abstract: A catheter type laser illuminating apparatus for thermally removing an atheroma generated in a blood vessel. The illuminating apparatus comprises a catheter arranged to be inserted into a blood vessel, the catheter being equipped with an ultrasonic transducer for transmitting and receiving an ultrasonic wave to generate an electric signal corresponding to the reception ultrasonic wave. The catheter is further equipped with a laser transmission fiber for emitting the laser light. Also included in the illumination apparatus is a M-mode image producing section for producing an image representative of the dimension of the atheroma on the basis of the electric signal from the ultrasonic transducer. The image is displayed on a CRT in a corresponding relation to an illumination condition of the laser light to the atheroma which is at least one of an illumination time and an illumination power.

Abstract: A method and apparatus used in combination with an existing laser for controlling the temperature of a laser powered tool includes a temperature control device coupled between the output of the laser and the optical fiber delivery system to monitor the temperature of the optical fiber delivery system and attenuate the laser output power to achieve a desired temperature level. The device establishes a beam path and provides a beam deflector that is variably positioned in the beam path to deflect a variable portion of the laser beam toward a laser wavelength-absorbing heat sink. An infrared detector is directed to receive emissions from the laser tool, and electronic circuitry processes the signal from the infrared detector to determine the temperature in the delivery system and generate an actuator signal to position the beam deflector so that beam deflection is increased or decreased to achieve a predetermined, desirable temperature level in the delivery system.

Abstract: A heart-synchronized vacuum-assisted pulsed laser technique generates a valve control signal in response to the ECG of a beating heart which is to be synchronized with the laser; the valve control signal is applied to a valve to open it and permit laser gas to be delivered to the gas inlet of the laser assisted by the draw from a vacuum source at the gas outlet of the laser, to produce a predetermined range of laser gas pressure in the laser; the valve control signal is ceased after the predetermined range of laser gas pressure has been reached to end the gas flow through the laser and enable the rebuilding of the vacuum in the vacuum source; and a laser firing signal is generated to fire the laser when the laser gas pressure is in the predetermined range.

Abstract: A laser surgical instrument is embodied as a handpiece supportable on the wrist and forearm of a surgeon. The handpiece is connected by an umbilical cord to a remote console. An internal shutter mechanism is actuated by steady finger pressure applied by the surgeon at a fixture grasped by the hand during use. An annular aiming beam is projected through an aperture in a physical distance gauge to focus concentric with the surgical laser beam.

Abstract: A heart-synchronized pulsed laser system includes a laser; a device for sensing the contraction and expansion of a beating heart to be synchronized with the laser; a device, responsive to the device for sensing, for generating a trigger pulse; a control for positioning the leading edge of the trigger pulse during the contraction and expansion cycle of the heartbeat; a control for defining the width of the trigger pulse to occur during the heartbeat cycle; and a circuit responsive to the trigger pulse for firing the laser to strike the beating heart at the time indicated by the trigger pulse position and for the period indicated by the width of the trigger pulse.

Abstract: Surgical procedures on biological tissue are carried out with the aid of a laser with substances being applied to the tissue before or during the treatment and these substances are absorbent in the range of the wavelength of the laser beam. A surgical manipulator can be provided and equipped with suction and irrigation channels and the substances can be directed to one of these channels via a metering unit. The application of substances such as sulfisomidine or sulfacetamide increases the ablation rate and reduces the threshold of the ablation process. At the same time, sensitive structures are protected from the damaging effects of the laser radiation as well as from the stray radiation and fluorescence radiation triggered by the laser radiation during the application of microsurgery to the eye.

Abstract: A control apparatus for a pumped rod-type laser includes an arc lamp disposed to illuminate the lasing medium, such as a NdYAG crystalline rod. The apparatus includes a full wave rectifier to power the arc lamp, and a MOSFET switching circuit to turn on and off the arc lamp power at controlled times during each half cycle of the power waveform so that the laser medium is pumped and optically discharged once during each half cycle of the power supply. The laser power output is measured by a photodetector during each half cycle, and the photodetector output is integrated and compared with a manually set, variable laser output power level. When the actual laser power reaches the preset power level, the comparator initiates turning off the MOSFET switching circuit power for that respective half cycle of the power waveform.

Abstract: Apparatus and methods for laser fusion of biological structures are disclosed employing a laser for delivery of a beam of laser radiation to an anastomotic site, together with a reflectance sensor for measuring light reflected from the site and a controller for monitoring changes in the reflectance of the light of the site and controlling the laser in response to the reflectance changes. In one embodiment, the laser radiation is delivered through a hand-held instrument via an optical fiber. The instrument can also include one or more additional fibers for the delivery of illumination light (which can be broadband or white light or radiation from a laser diode) which is reflected and monitored by the reflectance sensor. Reflectance changes during the course of the fusion operation at one or more wavelengths can be monitored (or compared) to provide an indication of the degree of tissue crosslinking and determine when an optimal state of fusion has occurred.

Abstract: A laser treatment apparatus is to treat a site of disease of a patient with a laser beam.

Abstract: A method for carrying out surgical procedures using a laser and a laser surgical tool includes the provision of a temperature control device associated with the laser which monitors the temperature of the surgical tool and delivery system and governs the laser power output to achieve a desired temperature level. The temperature control device may be used either to prevent heating of the surgical tool and delivery system beyond it structural tolerance, or to maintain a predetermined temperature level which is optimized for a particular surgical or medical procedure. The delivery system may comprise an optical fiber, and the surgical tool may comprise the output end of the optical fiber which is free of any additional surgical cutting implement.

Abstract: Apparatus for selective destruction or inactivation of cells is disclosed wherein cells are arrayed in a plane for successive illumination, by optical X-Y scanning devices, with a first low power red light beam to produce in particular cells certain radiations responsive to the illumination. These response radiations are detected and used to enable a second higher powered light beam directed through substantially the same optical scanning paths, to destroy or inactivate the cells producing the response radiations. The illumination, response, detection, and high power radiation steps are accomplished by devices acting in times short as compared to the X-Y scanning devices so as to make the accurate treatment of each of large numbers of cells highly effective.

Abstract: The method and apparatus of the invention use a beam of laser emitted optical energy to effect wound closure and reconstruction of biological tissue. In response to input as to tissue type and thickness, a computer determines the output power, exposure time and spot diameter of the emitted beam to control the application of optical energy to produce thermal heating of biological tissue to a degree suitable for denaturing the tissue proteins such that the collagenous elements of the tissue form a "biological glue" to seal immediately and/or to reconstruct the tissue being heated. In a given embodiment, the computer directly controls output power of the laser by regulating the laser's input current, and limits exposure time by deactivating a shutter mechanism when the determined time is reached. Beam diameter is manually set in response to a displayed value for a sliding scale that controls the working distance between the end of a fiber optic beam guide and the tissue site.

Abstract: A control system for a laser catheter device wherein the control system is provided with means for determining the intensity of laser beam energy at two points, one of which is at the distal tip end thereof, and with the other being interposed along a transmitting column remote from both the source of laser beam energy and the distal tip. A beam splitter means(dichroic filter) is provided for diverting a first portion of the laser beam energy onto a first detector means. Energy passing through the beam splitter is ultimately directed onto a fluorescent member or device disposed adjacent the distal tip, with the fluorescent member or means being capable of emitting or generating radiant energy at a wavelength significantly different from that of the incident laser beam energy. The radiant energy generated by the fluorescent means is directed onto a second surface of the beam splitter means, and ultimately onto a second detector means.

Abstract: A control apparatus for a pumped rod-type laser includes an arc lamp disposed to illuminate the lasing medium, such as a NdYAG crystalline rod. The apparatus includes a full wave rectifier to power the arc lamp, and a MOSFET switching circuit to turn on and off the arc lamp power at controlled times during each half cycle of the power waveform so that the laser medium is pumped and optically discharged once during each half cycle of the power supply. The laser power output is measured by a photodetector during each half cycle, and the photodetector output is integrated and compared with a manually set, variable laser output power level. When the actual laser power reaches the preset power level, the comparator initiates turning off the MOSFET switching circuit power for that respective half cycle of the power waveform. The full wave rectified power supply also permits the use of 110 VAC utility power.