System and method for treating a therapeutic site

Abstract

A targeting catheter is used to locate an arteriotomy, such as is formed during a femoral artery catheterization procedure. The targeting catheter includes one or more targeting aids, such as an inflatable balloon or sensor (e.g., Doppler or temperature sensor), to locate the arteriotomy. The targeting aid may be positioned at the arteriotomy. An ultrasonic beacon on the catheter may then be located relative to a therapeutic ultrasonic applicator (e.g., by using acoustic time-of-flight) so that the focus of ultrasonic energy from the applicator can be aligned with the arteriotomy.

1 . A system for delivering focused ultrasound to a therapeutic site adjacent a blood vessel, the system comprising:
 an imaging transducer;   a plurality of receivers configured to receive one or more signals; and   at least one annular therapeutic transducer disposed proximate the imaging transducer and the plurality of receivers, wherein a focus of the at least one therapeutic transducer is adjusted based at least in part on the one or more signals received by the plurality of receivers.   
     
     
         2 . The system of  claim 1 , wherein the imaging transducer comprises a Doppler transducer. 
     
     
         3 . The system of  claim 1 , wherein each of the plurality of receivers comprises an acoustic time of flight receiver. 
     
     
         4 . The system of  claim 3 , wherein each of the receivers is configured to receive one or more signals from a piezoelectric beacon configured to emit a sonic signal. 
     
     
         5 . The system of  claim 3 , wherein each of the receivers is configured to receive one or more electromagnetic signals. 
     
     
         6 . The system of  claim 1 , further comprising a targeting catheter having a locating beacon. 
     
     
         7 . The system of  claim 6 , wherein each of the plurality of receivers is configured to receive one or more signals from the locating beacon. 
     
     
         8 . The system of  claim 7 , wherein each of the plurality of receivers is configured to receive one or more signals from the locating beacon at least when the locating beacon is disposed within a blood vessel and when the receivers are disposed outside of the blood vessel. 
     
     
         9 . A method of detecting tissue movement relative to an ultrasound applicator, the method comprising:
 emitting a first set of ultrasonic pulses from one or more ultrasonic transducers, wherein the one or more ultrasonic transducers are located outside of a patient, and wherein the first set of pulses are directed towards a therapeutic site in tissue disposed inside the patient;   detecting a first set of ultrasonic echoes with the one or more ultrasonic transducers;   emitting a second set of ultrasonic pulses from the one or more ultrasonic transducers, wherein the one or more ultrasonic transducers are located outside of the patient, and wherein the second set of pulses are directed towards the therapeutic site;   detecting a second set of ultrasonic echoes with the one or more ultrasonic transducers;   comparing the first and second ultrasonic echoes; and   determining an amount of relative tissue movement based at least in part on the comparison and directional vectors between the one or more ultrasonic transducers and the therapeutic site; and   adjusting a focus of the ultrasound applicator based at least in part on the determined amount of relative tissue movement; and   emitting a dose of therapeutic ultrasonic energy from the ultrasound applicator.   
     
     
         10 . The method of  claim 9 , wherein an intravascular catheter is disposed within a blood vessel. 
     
     
         11 . A method of determining a location of a therapeutic site adjacent a blood vessel in a body relative to a therapeutic applicator, the method comprising:
 inserting a targeting catheter into the body;   identifying the location of the therapeutic site using the targeting catheter; and   determining a position of the targeting catheter relative to the therapeutic applicator.   
     
     
         12 . The method of  claim 11 , further comprising aligning the targeting catheter with the therapeutic applicator. 
     
     
         13 . The method of  claim 11 , wherein the determining step utilizes triangulation. 
     
     
         14 . The method of  claim 11 , wherein the targeting catheter comprises a transmitter. 
     
     
         15 . The method of  claim 14 , wherein the transmitter comprises a piezoelectric emitter. 
     
     
         16 . The method of  claim 14 , wherein the therapeutic applicator comprises a plurality of receivers configured to receive one or more signals emitted from the targeting catheter. 
     
     
         17 . The method of  claim 16 , wherein the plurality of receivers are disposed about the at least one transducer. 
     
     
         18 . The method of  claim 11 , wherein the targeting catheter comprises a receiver. 
     
     
         19 . The method of  claim 11 , further comprising adjusting a focus of the therapeutic applicator based at least in part on the determined position of the targeting catheter. 
     
     
         20 . The method of  claim 19 , further comprising emitting a dose of therapy from the therapeutic applicator such that the therapeutic site is exposed to the dose. 
     
     
         21 . The method of  claim 11 , wherein the therapeutic applicator comprises at least one annular transducer.