Abstract: A dressing for wounds or dermal ulcers. The dressing includes a semi-permeable, transparent polyurethane film and a plurality of concentric polyethylene foam rings or disks. Application of foam rings to a semi-permeable thin film permits modification of the moisture/vapor transmission characteristic of the wound dressing which can be adjusted to suit the wound environment.

Abstract: A laser catheter includes an elongated tubular catheter body, one or more optical fibers extending through the catheter body and a catheter window mounted at the distal end of the catheter body. The optical fibers direct laser energy through the catheter window for removal of biological material. A diffraction grating is formed on the proximal surface of the catheter window in alignment with laser energy from the optical fibers. The laser energy is modified by the diffraction grating to provide a desired spatial distribution pattern. Preferably, the diffraction grating provides a diverging beam suitable for forming a hole in an obstruction, the hole having a diameter that is approximately the same as the diameter of the catheter. The diffraction grating enables formation at the distal end of the catheter of a beam pattern having an elliptical or other noncircular cross section.

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: A disposable biopsy forceps includes an elongate tubular member having proximal and distal ends. Manually operated actuating means is mounted to the proximal end of the flexible tubular member. A biopsy jaw assembly is mounted to the distal end of the tubular member and is operatively connected to the actuating means by a control wire extending through the tubular member.

Abstract: A precalibrated sensing system for determining a blood parameter such as the partial pressures of oxygen (pO.sub.2) and carbon dioxide (pCO.sub.2), and the negative logarithm of hydrogen ion activity (pH). A dry sensor is provided which may be calibrated in the factory, packaged, sterilized and stored, without requiring recalibration prior to use.

Abstract: A balloon dilatation catheter device and method adapted for use in percutaneous transluminal angioplasty, where the catheter has several lumens so arranged to more efficiently channel and cleanse harmful materials from within the catheter, thereby preventing dangerous materials, such as air, from entering the body cavity where air or other gas or liquid may cause harm or death. The device includes a balloon inflation lumen for inflating/deflating a balloon on the distal end of the catheter, and a directional flow lumen having a one-way valve, which prevents flow in the reverse direction. The catheter may also include a guidewire lumen for introducing guidewires or liquids into the proximal end of the catheter for use in the distal end, which may lie within a body lumen.

Abstract: The invention provides an irrigation and aspiration device for use in laparascopic and other types of surgery. When connected to existing irrigation and suction sources, the device provides fingertip control of the fluid connections between the sources and a tube. The device comprises a valve housing with two valve assemblies inside, mounted and configured to take advantage of the static pressure supplied by the sources for increasing seal integrity of the valves. The internal chambers of the valve housing are also configured such that when one valve is open, the pressure differential across the other valve is increased, further increasing its seal integrity.

Abstract: A catheter shaft and catheter are formed by spirally rolling a thin polymeric film about a mandrel into a tubular form and fixing the spirally wound film in the tubular form. Additional elements and films may be incorporated into the spirally wound tube to provide a catheter having varied characteristics and functions.

Abstract: A catheter having a lumen for delivering air and a lumen for delivering fluid, such as water. Each lumen extends from the proximal end to the distal end of the catheter. An opening is formed between the air and fluid lumens adjacent the distal end to allow communication between the lumens to allow mixing of the air and fluid. A syringe having a fluid barrel and an air barrel is connected to the catheter to communicate with the respective fluid and air lumens.

Abstract: A diffusion tip coupled to the end of an optical fiber for directing laser energy outwardly in a cylindrical or other desired radiation pattern. The diffusion tip includes a core, a cladding around the core and a jacket around the cladding. The cladding has an index of refraction that is lower than that of the core and has a thickness selected to transmit a portion of the laser radiation that is carried through the optical fiber so that laser radiation penetrates through the cladding and the jacket over the length of the diffusion tip. The thickness of the cladding is about the same as or slightly less than the penetration depth of the evanescent field in the cladding. The cladding can be tapered along the length of the diffusion tip to provide a uniform radiation pattern. The diffusion tip is particularly useful in a laser balloon catheter utilized in coronary angioplasty.

Abstract: The device for use with a catheter includes a sleeve 21 for assembly onto the shaft of a catheter 1, between the catheter shaft and a Tuohy-Borst connector 3. The internal diameter of the sleeve 21 is complementary with the external diameter of the catheter 1 so that the catheter is movable within the sleeve. The external diameter of the sleeve is such that when the Tuohy-Borst connector is closed, a seal is formed between the sleeve and the connector. A flange 24 is provided at one end of the device for engagement with the connector, to prevent movement of the sleeve with the catheter. The internal diameter of the sleeve 21 is also complementary with the external diameter of the catheter 1 so as to provide an annular space about the catheter whereby, in use, a controlled amount of backbleed of blood is allowed.

Abstract: A balloon dilatation catheter, usable in percutaneous transluminal angioplasty, is formed so that portions of the catheter both distally and proximally of the balloon have varyinq degrees of radiopacity. A portion of the catheter distally of the balloon presents a dark image under fluoroscopy while a portion located proximally of the balloon displays a moderately radiopaque image under fluoroscopy. The portion of the catheter in the region of the balloon may have a moderate, light or no radiopaque means.

Abstract: A guidewire system for use in catheter exchanges avoids the need for a separate exchange wire by connecting an extension wire to the proximal end of the guidewire thereby increasing the effective length of the guidewire to permit a catheter exchange. The proximal end of the guidewire is attached to the distal end of the exchange wire by a disconnectable, reattachable connection which avoids deformation of the connected joint. The connection includes a male element in the form of a reduced diameter rod extending axially from the proximal end of the guidewire and a female element attached to the distal end of the extension wire. The female element includes a helical coil receptive to the rod and dimensioned to receive the rod in an interference fit requiring the spring to expand. Separation is effected by imparting a combined twisting and axial separation motion to the guidewire and extension wire.

Abstract: A connection system for a guidewire and a guidewire extension includes a manually actuable locking mechanism for locking or unlocking the mated ends of the wires together. One of the mating ends includes a socket. The other mating end includes a wire having a reduced diameter end portion that carries a sleeve. An enlarged wedging element is attached to the tip of the wire. The arrangement of the wedging element and sleeve are insertable into the socket and, after insertion, the arrangement is manipulated to draw the wedging element into the end of the sleeve. The sleeve thus is wedged radially outwardly into firm engagement with the inner surface of the socket. The lock is easily released by pulling the sleeve axially away from the wedging element.

Abstract: Laser energy produced by a laser operating in the mid-infrared region (approximately 2 micrometers) is delivered by an optical fiber in a catheter to a surgical site of biological tissue removal and repair. Disclosed laser sources which have an output wavelength in this region include: Holmium-doped Yttrium Aluminum Garnet (Ho:YAG), Holmium-doped Yttrium Lithium Fluoride (Ho:YLF), Holmium-doped Yttrium-Scandium-Gadolinium-Garnet (HO:YSGG), Erbium-doped YAG, Erbium-doped YLF and Thulium-doped YAG. Laser output energy is applied to a silica-based optical fiber which has been specially purified to reduce the hydroxyl-ion concentration to a low level. The catheter may be comprised of a single optical fiber or a plurality of optical fibers arranged to give overlapping output patterns for large area coverage. In a preferred application for the removal of atherosclerotic plaque, a Holmium-doped laser operating in the wavelength range of from about 1.9 to about 2.1 micrometers is preferred.

Abstract: An oxygen sensor is provided for determination of the partial pressure of oxygen. In one aspect, the invention consists of oxygen-quenchable luminescent lanthanide complexes for an oxygen sensor. The complexes are oxygen-quenchable even though immobilized in a solid matrix, such as a solid polymeric matrix, and preferably are terbium complexes of Schiff base or .beta.-diketone ligands. Certain preferred processes are described for improving the oxygen sensitivity of the lanthanide complexes. In another aspect, the invention consists of a combination measuring and reference analyte sensor containing both quenchable and nonquenchable luminescent materials. The materials luminesce at different wavelengths and thus may be transmitted together down a single optical fiber and later discriminated by means of filters and separtely detected. In a third aspect, the invention consists of a low-noise phosphorescent analyte sensor employing a gatable detector.

Abstract: A small diameter steerable guidewire that is used to guide a catheter in transluminal coronary angioplasty is provided with a pair of electrodes for measuring the cross-sectional area of a blood vessel and for measuring blood flow. The guidewire includes a shaft and a tip attached to the distal end of the shaft. The shaft is torsionally rigid along its length and includes a conductive main tube and a wire extending through the main tube. The tip, which can be bent to a prescribed curve when relaxed, is sufficiently flexible to adapt to and follow the contours of a blood vessel. The tip includes a tapered extension of the wire in the shaft. A proximal electrode and a distal electrode are coaxially mounted on the tapered wire and are electrically connected to the main tube and the wire, respectively. The electrodes are axially spaced apart by a predetermined distance. The distal electrode is preferably a conductive, helically-wound spring.

Abstract: A flexible, lubricious organic polymeric coating is formed by applying a mixture of an isocyanate, a polyol, poly(ethylene oxide), and carrier liquid to a surface to be coated. The carrier liquid is removed and the mixture reacted to form a polyurethane coating with associated poly(ethylene oxide) giving a highly lubricious, abrasion resistant, flexible coating particularly suitable for use as a protective lubricious coating on devices introduced into the body.

Abstract: An irrigation system for irrigating and pressurizing a body cavity during an endoscopic procedure, such as during arthroscopy, includes a source of irrigation liquid, a pneumatically driven pump for pumping irrigation liquid from the source into the body cavity. The pump develops pulsatile flow and its operation is controlled by a pressure regulator that regulates the pressure of air applied to the pump. The system enables disablement of the pumping function of the pump while permitting gravity flow of irrigation liquid to the body cavity. The pump and associated tubing is inexpensive and adapted for one-time, disposable use.

Abstract: A disposable biopsy forceps includes an elongate tubular member having proximal and distal ends. Manually operated actuating means is mounted to the proximal end of the flexible tubular member. A biopsy jaw assembly is mounted to the distal end of the tubular member and is operatively connected to the actuating means by a control wire extending through the tubular member. Several embodiments of jaw arrangements are disclosed. At least the cups and cutting rim portion of the cutting jaws retain an edge sufficiently sharp to cut tissue.