초록 ▼

An ultrasound catheter comprises a coaxial cable of electrical conductors with a piezoelectric element at its distal end. The piezoelectric element is shaped and disposed according to the desired ultrasonic field. When an electrical signal from a signal generator is connected to the electrical condu

An ultrasound catheter comprises a coaxial cable of electrical conductors with a piezoelectric element at its distal end. The piezoelectric element is shaped and disposed according to the desired ultrasonic field. When an electrical signal from a signal generator is connected to the electrical conductors, the piezoelectric element mechanically deforms in response and generates ultrasonic energy. An alternative embodiment of the present invention is a hollow tubular catheter of flexible polymer has at its distal end a cylindrical piezoelectric element connected to electrical conductors running the length of the catheter. The piezoelectric cylinder may be tapered, segmented, shortened, etc. according to the desired focusing of the ultrasonic field, which is preferably forwardly focused. In either embodiment the catheter is threaded through a patient's vasculature and brought in close proximity to a vascular occlusion. Thrombolytic agents are released from the ultrasonic catheter or a second catheter in close proximity. These agents and ultrasonic energy from the ultrasound catheter result in breakup of the occlusion through sonophoresis.

대표청구항 ▼

[ We claim:] [1.] An improved method for opening occluded vascular elements of the type wherein ultrasound and thrombolytic agents are used to dissolve an occlusion, the improvement comprising the steps of:inserting an ultrasound catheter having a longitudinal axis including a shaped, distally dispo

[ We claim:] [1.] An improved method for opening occluded vascular elements of the type wherein ultrasound and thrombolytic agents are used to dissolve an occlusion, the improvement comprising the steps of:inserting an ultrasound catheter having a longitudinal axis including a shaped, distally disposed and forwardly oriented piezoelectric ultrasound generating tip into a patient's vascular system so that the tip of said catheter is in proximity to a vascular occlusion;energizing the shaped piezoelectric ultrasound generating tip to radiate concentrated wavefronts of a forwardly focussed beam of ultrasound energy from said transducer toward said occlusion in the direction of said longitudinal axis; andreleasing thrombolytic agents in proximity of said occlusion so that sonophoresis of said occlusion occurs.