Abstract: An apparatus and method for guiding and centering a catheter to a treatment site within a passageway in the human body includes a flexible tube having a distal end dimension to pass freely along the passageway, and a proximal end adapted to extend outside the body. The flexible tube is provided with a peripherally expandable zone at the distal end of the tube and a longitudinal lumen through the flexible tube dimension for passing a catheter therethrough. The distal end of the flexible tube is guided to a desired location within the passageway. The peripheral zone at the distal end of the tube is then expanded so that the expandable zone pushes against the inner wall of the passageway to center the distal end of the tube within the passageway. With the tube positioned within the passageway, a catheter is passed through the longitudinal lumen of the flexible tube.

Abstract: An apparatus and method for guiding and centering a catheter to a treatment site within a passageway in the human body includes a flexible tube having a distal end dimension to pass freely along the passageway, and a proximal end adapted to extend outside the body. The flexible tube is provided with a peripherally expandable zone at the distal end of the tube and a longitudinal lumen through the flexible tube dimension for passing a catheter therethrough. The distal end of the flexible tube is guided to a desired location within the passageway. The peripheral zone at the distal end of the tube is then expanded so that the expandable zone pushes against the inner wall of the passageway to center the distal end of the tube within the passageway. With the tube positioned within the passageway, a catheter is passed through the longitudinal lumen of the flexible tube.

Abstract: An apparatus and method for opening an osbstucted tubular passageway in the human body. A first catheter having a distal end dimensioned to pass freely along a tubular passageway is guided to the obstruction. A proximal end of the first catheter is adapted to extend outside the human body and is coupled to a source of coherent radiation. Coherent radiation is transmitted from the source to the distal end of the first catheter to permit the coherent radiation to be directed against the obstruction to bore a passageway through the obstruction. After a passageway has been bored through the obstruction, the first catheter is removed from the tubular passageway. A second catheter having a distal end dimensioned to pass freely along the tubular passageway, a proximal end adapted to extend outside the human body, and a peripheral elastic expandable zone spaced from the distal end is guided into the passageway through the obstruction.