| abstract |
An ultrasound apparatus (12) for thermally induced renal neuromodulation, comprising: a catheter (16) configured for intravascular insertion into a renal blood vessel of a human patient; and a therapeutic assembly (21) positioned along the catheter (16), wherein the therapeutic assembly (21) comprises a polyvinylidene difluoride (PVDF) ultrasound transducer (41, 53) configured to transmit ultrasound waves to Target nerve fibers throughout the renal blood vessel to achieve thermal renal neuromodulation by heating, and a recessed portion (57), in which the PVDF ultrasound transducer is configured to transmit ultrasound waves over less than full 360 degrees in the blood vessel, in which the therapeutic assembly is attached to a flexible part of the distal end of the catheter (20, 16), and in which the PVDF ultrasound transducer is positioned within the recessed part of the therapeutic assembly (57, 21), and wherein the therapeutic assembly (21) is configured to engage at least a portion of a wall of the renal blood vessel during transmission of ultrasound waves to the target nerve fibers, and wherein the recessed portion (57) of the therapeutic assembly (21) is sized and shaped such that the PVDF ultrasound transducer (41, 53) positioned within the recess remains out of contact with the renal blood vessel wall during treatment. |