Abstract: A catheter wherein the "effective over-the-wire" length is adjustable. The catheter includes an elongated inflation shaft having a longitudinal inflation lumen, an extension shaft disposed distal to the inflation shaft and through which the inflation lumen is continued, a balloon element disposed at the distal end of the extension shaft and in fluid communication with the inflation lumen, a guidewire shaft having a longitudinal guidewire lumen which extends from the distal end of the balloon member, through the balloon member and the extension shaft, to the proximal end of the extension shaft, and a telescoping portion. The telescoping portion comprising first and second telescoping tubes which are slidably mounted on the inflation shaft and the extension shaft. The first and second telescoping tubes are sized so that the first telescoping tube can be retracted into the second telescoping tube. The extension shaft is sized so that it can be retracted into the first telescoping tube.

Abstract: A method and apparatus are provided for withdrawing an indwelling over-the-wire catheter from an indwelling guidewire in which the guidewire is of a conventional length and is maintained in its indwelling position as the catheter is withdrawn. The position of the guidewire is maintained by constraining a segment of the catheter shaft and its included guidewire in a non-linear configuration such that the guidewire remains in its position as the catheter is withdrawn. The invention may be used to perform catheter exchanges without requiring the use of exchange wires, extension wires, rapid exchange catheters or special devices to connect the guidewire to the guide catheter.

Abstract: A locking apparatus for use with a catheter which includes a catheter body, first and second slidable components which are slidable with respect to the catheter body, and a hub disposed at the proximal end of the catheter body, and a method of using the locking apparatus. The locking apparatus includes a locking device engageable with the hub for locking the first slidable component in a fixed position relative to the hub, and an extension member that is integral with the hub and engageable with the locking device for locking the second slidable component in a fixed position relative to the hub.

Abstract: A catheter wherein the "effective over-the-wire" length is adjustable. The catheter includes an elongated inflation shaft having a longitudinal inflation lumen, an extension shaft disposed distal to the inflation shaft and through which the inflation lumen is continued, a balloon element disposed at the distal end of the extension shaft and in fluid communication with the inflation lumen, a guidewire shaft having a longitudinal guidewire lumen which extends from the distal end of the balloon member, through the balloon member and the extension shaft, to the proximal end of the extension shaft, and a telescoping portion. The telescoping portion comprising first and second telescoping tubes which are slidably mounted on the inflation shaft and the extension shaft. The first and second telescoping tubes are sized so that the first telescoping tube can be retracted into the second telescoping tube. The extension shaft is sized so that it can be retracted into the first telescoping tube.

Abstract: A guidewire and catheter are adapted for advancement through tight or tortuous vascular anatomy by providing detachably connectible threaded elements at the distal ends of each of the catheter and guidewire. When threaded together, the combined catheter and guidewire provide enhanced column strength to facilitate pushing the two together through the vascular anatomy. Alternately, the guidewire may be rotated in a manner that draws the catheter in screw-like fashion in a distal direction.

Abstract: A guidewire including a core wire extending into a lumen of a helical coil and having a proximal end of the helical coil fixedly attached thereto. At least one round forming wire is fixedly attached to a distal region of the core wire and extends through the lumen of the helical coil. A rounded protrusion is provided at a distal end of the helical coil with the round forming wire(s) and the helical coil fixedly attached thereto.

Abstract: An exchange length guidewire for use in percutaneous transluminal coronary angioplasty is formed in two sections including a proximal section and a distal section. The proximal end of the distal section is rotatably attached to the distal end of the proximal section so that it may be rotated freely with respect to the proximal section. The proximal section may be maintained in a coiled configuration in a storage hoop while the distal portion may be used as a steerable guidewire to assist in navigating a catheter to the intended vascular treatment site. When it is desired to perform a catheter exchange, the proximal section is removed from the storage hoop to permit the wire to extend to its full exchange length, typically slightly more than twice the length of the catheter. The catheter exchange then may be performed. Thereafter, the proximal section of the exchange wire may be reinserted into the storage hoop and while the distal portion may continue to serve as a steerable guidewire.

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 dilation catheter having an inflatable member and an element for retaining a curved shape, and a method of using same to restore patency to an obstructed portion of the lacrimal system. The catheter is inserted into the lacrimal system and the inflatable member is positioned in the obstructed portion. Insertion of the catheter is facilitated by mechanically imparting a curved shape to a distal portion of the catheter. The inflatable member is inflated to dilate the obstructed portion to restore patency to the lacrimal system. Preferably, the catheter includes one or more visually perceivable markers having a known spaced relationship to one of the ends of the inflatable member. Positioning of the inflatable member is assisted by aligning the marker relative to an opening into the lacrimal system.

Abstract: A laterally attachable and detachable tool for manipulating a guidewire includes a cylindrical body that terminates in a collet. A nut is threaded to the collet and can be tightened to draw the collet arms inwardly. The body and the nut each include a lateral slot of a width to receive the guidewire. The slot in the nut is registrable with the slot in the body to form a continuous slot, receptive to the guidewire, along the length of the tool.

Abstract: A dilatation catheter having an inflatable member and a method of using same to restore patency to an obstructed portion of the lacrimal system. The catheter is inserted into the lacrimal system and its inflatable member is positioned in the obstructed portion. The inflatable member is inflated to dilate the obstructed portion to restore patency to the lacrimal system. Preferably, the catheter includes one or more visually perceivable markers having a known spaced relationship to one of the ends of the inflatable member. Positioning of the inflatable member is assisted by aligning the marker relative to an opening into the lacrimal system.

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 tube and a wire extending through the 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 tube and the wire, respectively. The electrodes are axially spaced apart by a predetermined distance. Each electrode is preferably a conductive, helically-wound spring. The outside diameter of the steerable guidewire preferably does not exceed about 0.