Systems and methods for ultrasound applicator station keeping

• US 8,167,805 B2
• Filed: 10/19/2006
• Issued: 05/01/2012
• Est. Priority Date: 10/20/2005
• Status: Active Grant

• Current Assignee: Otsuka Medical Devices Co., Ltd. (Otsuka Holdings Company Limited)
• Original Assignee: Kona Medical, Inc.
• Inventors: Emery, Charles, Augustine, Larry, Lahman, Robyn, Perozek, David M., Zhang, Jimin
• Primary Examiner(s): Chen, Tse
• Assistant Examiner(s): Luong, Peter
• Application Number:
  US11/583,569
• Publication Number:
  US 20070239000A1
• Time in Patent Office: 2,021 Days
• Field of Search: 600/437, 600/438, 600/448, 600/459, 600/462, 600/439
• US Class Current: 600/439
• CPC Class Codes: A61B 17/0057 Implements for plugging an opening in the wall of a hollow or tubular organ, e.g. for sealing a vessel puncture or closing a cardiac septal defect sutures A61B17/04; closing rectum or urethra near body surface A61F2/0009
• CPC Class Codes: A61B 18/02 by cooling, e.g. cryogenic techniques devices for cooling specific reflex points of the body within cell-life limits A61H39/06
• CPC Class Codes: A61B 2017/00557 inflatable A61B2017/22051 takes precedence
• CPC Class Codes: A61B 2017/00637 for sealing trocar wounds through abdominal wall
• CPC Class Codes: A61B 2017/00641 for closing fistulae, e.g. anorectal fistulae
• CPC Class Codes: A61B 2090/372 Details of monitor hardware
• CPC Class Codes: A61B 2090/3784 both receiver and transmitter being in the instrument or receiver being also transmitter
• CPC Class Codes: A61B 2090/3929 Active markers
• CPC Class Codes: A61B 2090/3958 emitting a signal
• CPC Class Codes: A61B 2090/397 electromagnetic other than visible, e.g. microwave
• CPC Class Codes: A61B 34/25 User interfaces for surgical systems
• CPC Class Codes: A61B 5/026 Measuring blood flow A61B3/1233, A61B3/1241 take precedence
• CPC Class Codes: A61B 50/13 Trolleys, e.g. carts
• CPC Class Codes: A61B 8/0833 involving detecting or locating foreign bodies or organic structures
• CPC Class Codes: A61B 8/0841 for locating instruments
• CPC Class Codes: A61B 8/12 in body cavities or body tracts, e.g. by using catheters catheters per se A61M25/00
• CPC Class Codes: A61B 8/4405 Device being mounted on a trolley
• CPC Class Codes: A61B 8/445 Details of catheter construction
• CPC Class Codes: A61F 2/82 Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents stent-grafts for tubular structures of the body other than blood vessels A61F2/04; stent-grafts for blood vessels A61F2/07; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95; for closing wounds, or holding wounds closed A61B17/04 - A61B17/115; dilators A61M29/00
• CPC Class Codes: A61M 25/10 Balloon catheters A61M25/0125 takes precedence; embolectomy A61B17/22032; retractors A61B17/02; inflatable balloons for placing stents or stent-grafts A61F2/958 ; stomach balloons for treatment of obesity A61F5/0003; oesophagal tubes A61J15/00
• CPC Class Codes: A61N 7/02 : Localised ultrasound hyperthermia hyperthermia in general A61F7/00

Abstract

Systems and methods for maintaining the alignment of a therapeutic ultrasound applicator to a target site are described. Overlapping ultrasound signals are sent to a target tissue site and the echo detected. An algorithm is described for detecting tissue movement relative to the applicator based on comparison of the echo with a previously stored echo.

Claims

1. A method of applying therapeutic energy to a target region comprising a blood vessel, comprising:

emitting a first ultrasonic pulse from a first ultrasound transducer to tissue at a target point within the target region;

detecting a first ultrasonic echo from the blood vessel at a second and third ultrasound transducer, wherein the first ultrasonic echo is not detected at the first ultrasound transducer;

emitting a second ultrasonic pulse from either the second or third ultrasound transducer to the target point;

detecting a second ultrasonic echo from the blood vessel at the first ultrasound transducer and the non-transmitting second or third ultrasound transducer, wherein the second ultrasonic echo is not detected at the transmitting second or third ultrasound transducer;

comparing the echoes to previously recorded echoes to determine time shifts or phase differences between the detected echoes and the previously recorded echoes;

determining the amount of relative tissue movement using the time shifts or phase differences and pre-determined unit vectors of each ultrasound transducer;

adjusting a focus of a therapeutic ultrasound applicator based at least in part on the determined amount of relative tissue movement to keep the target point within the focus of the therapeutic applicator; and

emitting a dose of therapeutic ultrasonic energy from the therapeutic ultrasound applicator such that the target point is exposed to the dose.

2. The method of claim 1, comprising detecting the first and second ultrasonic echoes at least one additional ultrasound transducer.

3. The method of claim 1, wherein determining the amount of relative tissue movement comprises executing a recursive algorithm.