Abstract: A method for treating pigmentation abnormalities in human skin involves the use of a beam of laser radiation having an elongated cross-sectional area. The beam of pulsed laser radiation having an elongated cross-section is produced using a pulsed laser and a delivery system. An elongated area on the skin including a pigmentation abnormality is irradiated with the laser beam. The laser pulse parameters are tailored to the specific type of pigmentation abnormality (e.g., vascular lesions or tattoos) being treated. The beam may have a cross-sectional area characterized by an aspect ratio of greater than two. Also, the beam may have an elliptical cross-sectional area.

Abstract: A flashlamp-excited dye laser generates a pulsed output beam having a long pulse duration. The laser includes a pulse forming circuit which generates an excitation pulse having an amplitude which generally increases in coordination with the lasing threshold for the flashlamp-excited dye laser. The flashlamp-excited dye laser is driven with the pulse to produce a pulsed output beam of laser radiation of at least 500 microseconds in duration.

Abstract: An infrared fundus angiography camera and ICG angiography imaging procedure for improved visualization and diagnosis of vascular diseases of the eye, especially SRNV, features a narrow bandwidth non-coherent and decollimated infrared illumination source, an optical system for directing the infrared illumination onto the retina and for directing the resulting retinal image toward an image storage device, and an optical filter positioned between the retina and the image storage device for blocking the infrared illumination from entering the image storage device. An infrared laser produces infrared illumination and a opal glass, fiber array, or integrating sphere light diffuser positioned between the infrared laser and the optical system decollimates and makes the infrared illumination incoherent. The laser includes a temperature stabilized infrared laser diode having an output matched to the excitation peak of an infrared fluorescent dye, such as ICG.

Abstract: A fiber optic probe comprises a pair of substantially parallel optical fibers separated by a gap and positioned in a centrifuge tube which contains a stratified medium. The pair of fibers includes a transmit fiber for directing light from a light source into a substantially undisturbed portion of the stratified medium disposed in the gap. Light traversing the portion of the stratified medium in the gap is collected by a receive fiber and provides an indication of a light property of the portion of the stratified medium disposed in the gap. The pair of fibers are adapted to be moved in the stratified medium without significantly disturbing the stratification of the medium. As the fibers are moved, light property measurements can be obtained in other substantially undisturbed portions of the stratified medium.

Abstract: A fistula is created in the sclera of a glaucoma patient by creating a passageway through the conjunctiva into the subconjunctival space of the patient. The passageway may be realized by an incision but is preferably realized as the inner lumen of a needle or sheath. One option for creating such an incision is to use an optical fiber shaped like a needle to create the incision. The passageway enables an optical fiber to pass into the subconjunctival space. Liquid is then infused into the subconjunctival space to raise the conjunctiva slightly to heighten maneuverability of the optical fiber within the subconjunctival space. The optical fiber is then positioned near a target sight on the sclera of the patient's eye. Laser radiation is transmitted down the optical fiber to create a fistula.

Abstract: A flashlamp-excited laser for producing a pulsed beam of laser light of long duration (e.g., greater than 500 microseconds) comprises a flashlamp driven by a pulse forming circuit which generates a ramp pulse having an amplitude generally increasing with time during substantially the entire duration of the pulsed beam of laser light produced by the laser.

Abstract: An optical coupler couples optical fibers carrying high energy signals. The coupler includes an adapter thaat interfaces two optical connectors. The optical connectors are positioned within the adapter to bring two optical fibers into optical communication. The optical connectors fit into the adapter in a manner than imposes a gap of at least 0.001 inch and preferably between 0.003 to 0.005 inch between the optical fibers. Moreover, the optical connectors include bevelled ferrules that provide additional space at the interface between the fibers. The gap and the space between the fiber work in conjunction to minimize damage to the fibers.

Abstract: An apparatus for navigation of body cavities is comprised of an inner element and an outer element that surrounds the inner element. The inner element has a memorized preformed shape that it assumes when it is not disposed within the outer element. When in the outer element, the inner element is straightened by the rigidity of the outer element. The preformed shape of the inner element is adjustable. This preformed shape may be exploited to navigate branches and curves in the body cavities. The inner element may be a catheter or laser fiber, and the outer element may be a catheter or sheath. When the inner element is a catheter, the catheter may contain a shape retaining element such as a spring wire that enables it to memorize the preformed shape.

Abstract: A fiber optic endoscope has a shaft with a varying outer diameter. The distal end of the shaft is sufficiently small in outside diameter for maneuvering it through various body canals, and is useful in dilating body orifices to allow more proximal, longer-diameter portions of the shaft to penetrate. The endoscope shaft changes in thickness and is preferably in stages of different constant outside diameter. A flexible tip portion at the distal end of the shaft which is controllable from the endoscope handle may be included. Transitions between adjacent stages are smooth to provide a gradual transition between stages. The endoscope outer shaft is preferably made from a one-piece structure, portions of which are reduced in outside diamter to provide the different stages of the endoscope shaft.

Abstract: Calculi, stones, calcified tissue and other material are broken down for removal from within a body using laser pulses that are delivered via an optical fiber and have a wavelength, intensity, energy per pulse and pulse duration selected to break down the object into smaller particles without delivering energy sufficient to cause damage to other tissue.

Abstract: A tunable dye laser has been found particularly suited to selective photothermolysis. A longer pulse duration which makes the system suitable for a wider range of applications is obtained by modifying the laser to generate a spatially noncoherent beam. The optical system at each end of the laser cell, which may include a lens or spherical mirror, refocuses the aperture of the dye cell near to itself so that substantially all light emanating from the dye cell is returned to the dye cell until the light passes through one of the optic systems as a noncoherent laser beam. A tunable intracavity element tunes the laser across the gain curve of the dye solution. The pulse duration of the laser beam can be selected from a range of durations up to about one millisecond.

Abstract: An optics X-Y positioner has an optics support positioned within a housing having sides and front and rear walls. The optics support has a groove on one face which rides in an X direction along a ridge in a sliding guide plate. The guide plate slides within a flat groove in the Y direction in the rear wall of the housing. X and Y direction adjustment screws extend through sides of the frame and abut the optics support. A spring in tension is wrapped about the optics support in a circumferential groove to force the optics support against the adjustment screws.

Abstract: A dye laser fluid dye solution replenishment system in which the portion of the lasing fluid passing through the laser head which has been activated to a lasing condition is separated from the remainder of the unactivated dye solution and is separately restored before being recombined into the fluid flow path. The thus separated and degraded dye solution, representing only the degraded component of the flowing dye solution, is filtered to remove the degradation products and restored to the desired dye solution component concentrations. The thus restored solution is reinserted into the fluid flow path through the laser head.

Abstract: A fiber optic endoscope has a shaft with a varying outer diameter. The distal end of the shaft is sufficiently small in outer diameter for maneuvering it through various body canals, while the overall length of the shaft is rigid enough to allow axial and rotational translation of the shaft when controlled manually from a handle at the proximal end. The endoscope shaft may be n stages of different outer diameter or it may be uniformly tapered along its entire length. Either a step-tapered or a uniformly tapered version may include a flexible tip portion at the distal end of the shaft which is controllable from the endoscope handle.

Abstract: A tunable dye laser has been found particularly suited to selective photothermolysis. A longer pulse duration which makes the system suitable for a wider range of applications is obtained by modifying the laser to generate a spatially noncoherent beam. The optical system at each end of the laser cell, which may include a lens or spherical mirror, refocuses the aperture of the dye cell near to itself so that substantially all light emanating from the dye cell is returned to the dye cell until the light passes through one of the optic systems as a noncoherent laser beam. A tunable intracavity element tunes the laser across the gain curve of the dye solution. The pulse duration of the laser beam can be selected from a range of durations up to about one millisecond.

Abstract: A series inverter, high voltage capacitor charging circuit includes current sensors for sensing the current through each SCR in the circuit. The sensed current is used to vary the gating frequency of the SCRs and to preclude firing of an SCR until the other is in a stable off condition. The gating of each SCR is delayed by an amuont of time determined by a control capacitor charging circuit. That charging circuit is inhibited as long as one of the SCRs is conducting and once the load voltage has reached a predetermined level. The time constant of that charging circuit can be changed as the desired level is approached of if insufficient reverse bias is applied to an SCR for quick turn-off of the SCR. Resolution of the system can be increased by a shunt regulator which shorts the output transformer. The circuit can be disabled if the high voltage capacitor does not reach its set level within a given time.

Abstract: An endoscope provides a tube which is rigid enough along its length to be displaced by axial and rotational translation through open regions. The tip end of the tube is laterally flexible relative to the length of the tube. Wires connected to opposite sides of the flexible tip provide user control of the flexing of the tip. The sufficiently rigid length, flexible tip and dimensions of the tube enable placement of the tip end adjacent to kidney stones lodged in the ureter and calyxes of the kidney. The flexible tip further enables atraumatic use of the device. The tube may be multi-channeled to enable a view of the body canals and target stones in one channel, and to carry laser radiation by means of laser delivering fiber to the stones in another channel. Fiber optics may be employed between channels or within a channel of the tube to aid in the viewing of the pertinent body areas.