Ultrasound catheter and ultrasound catheter system

An ultrasound catheter system comprising:

• an ultrasound catheter;
• a drive device configured to drive the ultrasound catheter;
• the ultrasound catheter including:
• an outer sheath in which an accommodation lumen configured to extend from a proximal end to a distal end of the outer sheath;
• an inner sheath configured to move in the accommodation lumen along an axis of the outer sheath;
• a drive shaft configured to rotate in the inner sheath and/or the outer sheath;
• a transducer that is disposed on a distal side of the inner sheath in the accommodation lumen, and wherein the transducer is fixed to a distal end of the drive shaft;
• a first housing to which a proximal portion of the outer sheath is fixed and through which the drive shaft and the inner sheath pass;
• and
• a second housing that is disposed on a proximal side of the first housing, to which a proximal portion of the inner sheath is fixed, and wherein the second house is configured to rotatably hold the drive shaft;
• the outer sheath including:
• a bent portion that is bent and shaped in advance at a predetermined angle on a proximal side of a most distal end of the accommodation lumen;
• and
• a tubular portion that has an axis having a radius of curvature larger than a radius of curvature of an axis of the bent portion, the tubular portion being positioned on a distal side of the bent portion and on the proximal side of the most distal end of the accommodation lumen;
• the outer sheath configured to be rotatable with respect to the inner sheath;
• the drive device includes a proximal side support portion configured to support the second housing, a movement portion configured to move the proximal side support portion in an axial direction, a drive unit configured to transmit a rotational force to the drive shaft, and a distal side support portion configured to rotatably support the first housing;
• wherein the inner sheath extends to a vicinity of a proximal end of the transducer so as to cover substantially an entire length of the drive shaft;
• and
• wherein both the drive shaft and the inner sheath are configured to be inserted into the tubular portion of the outer sheath beyond the bent portion such that the transducer moves in the accommodation lumen in an axial direction beyond the bent portion.

An ultrasound catheter comprising:

• an outer sheath, the outer sheath includes an accommodation lumen configured to extend from a proximal end to a distal end of the outer sheath;
• a drive shaft configured to move in an axial direction of the outer sheath;
• a transducer fixed to a distal end of the drive shaft;
• wherein the outer sheath includes a proximal side tubular portion, a bent portion disposed distal of the proximal side tubular portion, and a tubular portion disposed distal of the bent portion, the bent portion being bent and shaped in advance at a predetermined angle, the tubular portion having a linear axis, the tubular portion being positioned on a distal side of the bent portion and on the proximal side of the most distal end of the accommodation lumen;
• the outer sheath is rotatable with respect to the drive shaft;
• wherein the transducer is configured to move in the accommodation lumen in the axial direction of the outer sheath beyond the bent portion;
• wherein the axis of the outer sheath is bent at the bent portion so as to define a bent angle of the bent portion;
• and
• wherein the most distal end of the accommodation lumen is away from a linear reference line, in which the axis of the outer sheath at a distal portion of the proximal side tubular portion is positioned, in a direction perpendicular to the reference line.