DRIVE SHAFT FOR ACOUSTIC IMAGING CATHETERS

摘要

A shaft (16) having inner members (40) and outer members (42) in interfering contact along their length, at least one of which comprises a wire, at least a portion of which is super-elastic, to achieve substantial mechanical fidelity and resistance to damage. The shaft (16) is placed within a catheter sheath (18). An ultrasound imaging catheter has a hollow catheter shaft, an ultrasound transducer in the shaft, and a drive shaft that rotates the transducer. The shaft comprises at least one metal coil having characteristic elastic deformation under stress in the range of about 3 % to 9 %, while a restraint means prevents torsional deflection of the coil. A drive shaft has a coil surrounded by a tube, a coil bonded to an inner coaxial cable, and an inner and outer coil that interfere with one another.