Systems and methods for making and using a motor distally-positioned within a catheter of an intravascular ultrasound imaging system

A catheter assembly for an intravascular ultrasound system, the catheter assembly comprising:

• a catheter having a longitudinal length, a distal end, and a proximal end, the catheter comprising a lumen extending along the longitudinal length of the catheter from the proximal end to the distal end;
• an imaging core with a longitudinal length that is substantially less than the longitudinal length of the catheter, the imaging core configured and arranged for inserting into the lumen and disposing at the distal end of the catheter, the imaging core comprising
• a rotatable driveshaft having a distal end and a proximal end,
• a rotatable mirror disposed at the distal end of the driveshaft,
• a motor coupled to the driveshaft, the motor comprising a rotatable magnet and at least two magnetic field windings disposed around at least a portion of the magnet, wherein the magnetic field windings are disposed on a rigid slotted material, and
• at least one fixed transducer positioned between the motor and the rotatable mirror, the at least one transducer having an aperture defined along a longitudinal axis of the at least one transducer, the aperture configured and arranged to allow passage of the driveshaft through the at least one transducer to the rotatable mirror, the at least one transducer configured and arranged for transforming applied electrical signals to acoustic signals and also for transforming received echo signals to electrical signals;
• at least one transducer conductor electrically coupled to the at least one transducer and in electrical communication with the proximal end of the catheter;
• and
• at least one motor conductor electrically coupled to the magnetic field windings and in electrical communication with the proximal end of the catheter.