Abstract: The invention provides apparatus for determining physiological characteristics of body lumens, such as the length of a blood vessel. A catheter allows measurements of the distance between a first target location and a second target location within a lumen by aligning a first marker on a first elongate member disposed within a lumen with the first target location. A second marker on a second elongate member disposed within the lumen is aligned with the second target location. The distance between the first and second markers is then directly measured from spaced-apart calibration marks along the second member, and the measured distance corresponds to the distance between the first and second target locations.

Abstract: The invention provides methods and apparatus for determining cross-sectional dimensions of body lumens, such as the diameter of a blood vessel. According to one exemplary method, the diameter of a blood vessel is measured by first inflating a balloon catheter within the lumen until the balloon diameter matches the lumen diameter. Inflation may be at a very low pressure and be constrained by the lumen, or may alternatively be controlled by monitoring the flow within the lumen. The balloon includes at least one measurement element which indicates the expanded balloon cross-sectional area, circumference, or diameter. Optionally, the measurement element provides a fluoroscopic, radiographic, or ultrasound indication of the cross-sectional dimension. In alternative embodiments, such dimensions may be transmitted to the distal end of the catheter, or determined after deflation and removal of the catheter.

Abstract: A tubular prosthesis is implanted at a target location within a body lumen by transluminally positioning the prosthesis and thereafter radially expanding the prosthesis to conform to an inner wall of the lumen. The prosthesis typically includes a braided tubular body and is typically provided with an everting or other structure for locking the prosthesis in its radially expanded configuration.

Abstract: A delivery catheter for a radially compressible tubular prosthesis comprises an elongate shaft slidably received within a tubular cover. The prosthesis is carried within a plurality of elongate, relatively hard runners, and is restrained in a radially compressed configuration by the cover. After introducing the catheter to a desired target location within a body lumen, the prosthesis may be released by proximally retracting the cover. The runners may optionally remain disposed about the prosthesis to be retracted separately, or, alternatively, the runners retract proximally with the cover as the prosthesis slides over the hard runner surfaces.

Abstract: A catheter introducing system includes an introducer catheter comprising a flexible sheath having a hemostasis valve and an obturator having a steering mechanism operated by a proximal actuator handle. The catheter introducer system will usually be introduced with the obturator inside of the flexible sheath so that the obturator can effect steering by laterally deflecting the distal end of the combined sheath and obturator. Such catheter introducing systems are particularly useful for large diameter sheaths which are not readily introduced over guide wires. A first exemplary hemostasis valve comprises a compressed foam insert having an axial lumen therein. A second exemplary hemostasis valve comprises an elastomeric insert which receives and seals over the catheter.