THERAPEUTIC APPARATUS FOR HEATING A SUBJECT

• US 20130217950A1
• Filed: 10/11/2011
• Published: 08/22/2013
• Est. Priority Date: 10/15/2010
• Status: Active Grant

• Current Assignee: National Institutes of Health (NIH) (Government of the United States of America), Profound Medical Inc. (Profound Medical Corp.)
• Original Assignee: National Institutes of Health (NIH) (Government of the United States of America), Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Kohler, Max Oskar, Partanen, Ari Ilkka Mikael, Dreher, Matthew Robert, Yarmolenko, Pavel Sergeyevich, Viitala, Antti Johannes, Enholm, Julia Kristina
• Granted Patent: US 10,099,069 B2
• Time in Patent Office: Days
• US Class Current: 600/1
• CPC Class Codes: A61B 2017/00084 Temperature
• CPC Class Codes: A61B 2018/00642 with feedback, i.e. closed loop control
• CPC Class Codes: A61B 2018/00666 using a threshold value
• CPC Class Codes: A61B 2018/00678 upper
• CPC Class Codes: A61B 2018/00791 Temperature
• CPC Class Codes: A61B 2090/374 NMR or MRI
• CPC Class Codes: A61N 2005/1085 characterised by the type of particles applied to the patient
• CPC Class Codes: A61N 2005/1087 Ions; Protons
• CPC Class Codes: A61N 5/10 X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy A61N5/01 takes precedence
• CPC Class Codes: A61N 7/00 Ultrasound therapy lithotripsy A61B17/22, A61B17/225; massage using supersonic vibration A61H23/00 ; using ultrasound for introducing media into the body A61M37/0092
• CPC Class Codes: A61N 7/02 Localised ultrasound hyperthermia hyperthermia in general A61F7/00
• CPC Class Codes: G01R 33/4804 Spatially selective measurement of temperature or pH
• CPC Class Codes: G01R 33/4814 MR combined with ultrasound
• CPC Class Codes: G01R 33/50 based on the determination of relaxation times , e.g. T1 measurement by IR sequences; T2 measurement by multiple-echo sequences

Abstract

A therapeutic apparatus (900, 1000) comprising a high intensity focused ultrasound system (904) for heating a target zone (940, 1022). The therapeutic apparatus further comprises a magnetic resonance imaging system (902). The therapeutic apparatus further comprises a memory (952) containing machine executable instructions (980, 982, 984, 986, 988, 990) for execution by a processor (944). Execution of the instructions cause the processor to: generate (702, 802) heating commands (964) which cause the high intensity focused ultrasound system to sonicate the subject; repeatedly acquire (704, 804) magnetic resonance data (954) during execution of the heating commands; repeatedly calculate (706, 806) a spatially dependent parameter (970); and repeatedly modify (708, 808) the heating commands in accordance with the spatially dependent parameter such that within the target zone the spatially dependent parameter remains below a first predetermined threshold and above a second predetermined threshold.

Claims

1. A therapeutic apparatus comprising:

a high intensity focused ultrasound system for heating a target zone of a subject;

a magnetic resonance imaging system for acquiring magnetic resonance data;

a processor for controlling the therapeutic apparatus;

a memory containing machine executable instructions for execution by the processor, wherein execution of the instructions cause the processor to generate heating commands which cause the high intensity focused ultrasound system to sonicate the subject in accordance with heating trajectories;

wherein execution of the instructions further cause the processor to repeatedly;

acquire the magnetic resonance data during execution of the heating commands;

calculate a spatially dependent parameter from the magnetic resonance data; and

modify the heating commands in accordance with the spatially dependent parameter such that within the target zone the spatially dependent parameter remains below a first predetermined threshold and above a second predetermined threshold and

wherein execution of the instructions further cause the processor to generate waiting commands which cause the high intensity focused ultrasound system to halt sonication for a predetermined period of time after executing the heating commands;

wherein execution of the instructions further cause the processor to generate maintaining commands which cause the high intensity focused ultrasound system to sonicate the subject in accordance with maintaining trajectories, wherein execution of the instructions further cause the processor to repeatedly;

acquire the magnetic resonance data during execution of the maintaining commands;

calculate the spatially dependent parameter from the magnetic resonance data acquired during execution of the maintaining commands; and

modify the maintaining commands in accordance with the spatially dependent parameter such that within the target zone the spatially dependent parameter remains below the first predetermined threshold and above the second predetermined threshold

wherein execution of the instructions cause the processor to allow the spatially dependent parameter to exceed the first predetermined threshold in the target zone if the sonication duration is less than a predetermined minimum sonication duration.

2. The therapeutic apparatus of claim 1, wherein execution of the instructions further cause the processor to:

acquire repeatedly the magnetic resonance data during execution of the waiting commands;

trigger execution of the maintaining commands if the spatially dependent parameter in the target zone is below the second predetermined threshold.

3. The therapeutic apparatus of claim 1, wherein execution of the instructions further cause the processor to halt sonication if a predetermined maximum sonication duration is exceeded.

5. The therapeutic apparatus of claim 1, wherein the spatially dependent parameter is any one of the following:

proton signal intensity, maximum proton signal intensity, minimum proton signal intensity, mean proton signal intensity, median proton signal intensity, T1 signal intensity, maximum T1 signal intensity, minimum T1 signal intensity, mean T1 signal intensity, median T1 signal intensity, T2 signal intensity, maximum T2 signal intensity, minimum T2 signal intensity, mean T2 signal intensity, median T2 signal intensity, T2-star signal intensity, minimum T2-star signal intensity, maximum T2-star signal intensity, mean T2-star signal intensity, mean T2-star signal intensity, temperature, minimum temperature, mean temperature, median temperature, minimum ultrasonic dose, maximum ultrasonic dose, median ultrasonic dose, maximum temperature deviation, minimum signal intensity, maximum signal intensity, mean signal intensity, median signal intensity, minimum thermal dose, mean thermal dose, median thermal dose, and maximum thermal dose, and combinations thereof.

6. The therapeutic apparatus of claim 1, wherein the trajectories define any one of the following:

concentric circles, concentric spheres, closed loops, closed surfaces, a single sonication location, and linear patterns.

7. The therapeutic apparatus of claim 1, wherein the instructions further cause the processor to:

receive medical image data;

receive a treatment plan, wherein the treatment plan is descriptive of the location of the target zone; and

generate the heating trajectories in accordance with the medical image data and the treatment plan.

8. The therapeutic apparatus of claim 7, wherein execution of the instructions further causes the processor to:

receive magnetic resonance data from the magnetic resonance imaging system; and

reconstruct the medical image data from the magnetic resonance data.

9. The therapeutic apparatus of claim 1, wherein the therapeutic apparatus further comprises a radiation therapy system, wherein execution of the instructions further causes the processor to perform any one of the following:

irradiate a radiation target in the subject after heating the target zone and irradiate the radiation target during heating of the target zone, and wherein the radiation target comprises at least a portion of the target zone.

10. The therapeutic apparatus of claim 9, wherein the radiation therapy system is any one of the following:

a proton therapy system, an x-ray therapy system, a charged particle therapy system, a carbon ion therapy system, a gamma radiation source therapy system, beta particle therapy system, and a LINAC.

11. The therapeutic apparatus of claim 1, wherein execution of the instructions further cause the processor to:

repeatedly calculate a second spatially dependent parameter from the magnetic resonance data;

halt sonication of the target zone by the high intensity focused ultrasound system if a predetermined change in the second spatially dependent parameter occurs.

15. The therapeutic apparatus of claim 1, further comprising a thermometry module to measure temperature in a measurement field and in particular to compute a thermal dose, wherein execution of the instructions cause the processor to generate heating commands which cause the high intensity focused ultrasound system to sonicate the subject in accordance with heating trajectories on the basis of the measured temperature and/or thermal dose.

4. (canceled)

12. A computer program product comprising machine executable instructions for execution by a processor controlling a therapeutic apparatus, wherein the therapeutic apparatus comprises a high intensity focused ultrasound system for heating a target zone of a subject, wherein the therapeutic apparatus further comprises a magnetic resonance imaging system for acquiring magnetic resonance data, wherein execution of the instructions causes the processor to generate heating commands which cause the high intensity focused ultrasound system to sonicate the subject in accordance with heating trajectories, wherein execution of the instructions further cause the processor to repeatedly:

acquire the magnetic resonance data during execution of the heating commands;

calculate a spatially dependent parameter from the magnetic resonance data; and

modify the heating commands in accordance with the spatially dependent parameter such that within the target zone the spatially dependent parameter remains below a first predetermined threshold and above a second predetermined threshold, and

allow the spatially dependent parameter to exceed the first predetermined threshold in the target zone if the sonication duration is less than a predetermined minimum sonication duration.

13. A method of operating a therapeutic apparatus, wherein the therapeutic apparatus comprises a high intensity focused ultrasound system for heating a target zone of a subject, wherein the therapeutic apparatus further comprises a magnetic resonance imaging system for acquiring magnetic resonance data, wherein the method comprises the steps of generating heating commands which cause the high intensity focused ultrasound system to sonicate the subject in accordance with heating trajectories, wherein the method comprises the steps of repeatedly:

acquiring the magnetic resonance data during execution of the heating commands;

calculating a spatially dependent parameter from the magnetic resonance data; and

modifying the heating commands in accordance with the spatially dependent parameter such that within the target zone the spatially dependent parameter remains below a first predetermined threshold and above a second predetermined threshold and

generating waiting commands which cause the high intensity focused ultrasound system to halt sonication for a predetermined period of time after executing the heating commands;

further to generate maintaining commands which cause the high intensity focused ultrasound system to sonicate the subject in accordance with maintaining trajectories, and to repeatedly;

acquiring the magnetic resonance data during execution of the maintaining commands;

calculating the spatially dependent parameter from the magnetic resonance data acquired during execution of the maintaining commands; and

modifying the maintaining commands in accordance with the spatially dependent parameter such that within the target zone the spatially dependent parameter remains below the first predetermined threshold and above the second predetermined threshold,

allowing the spatially dependent parameter to exceed the first predetermined threshold in the target zone if the sonication duration is less than a predetermined minimum sonication duration.

14. (canceled)