Apparatus for controlling thermal dosing in an thermal treatment system

• US 6,618,620 B1
• Filed: 11/28/2000
• Issued: 09/09/2003
• Est. Priority Date: 11/28/2000
• Status: Expired

• Current Assignee: InSightec Ltd.
• Original Assignee: Txsonics-Limited
• Inventors: Yagel, Roni, Vitek, Shuki, Freundlich, David, Vortman, Jacob, Brenner, Naama
• Primary Examiner(s): Walberg, Teresa
• Assistant Examiner(s): DVORAK, LINDA C
• Application Number:
  US09/724,670
• Time in Patent Office: 1,015 Days
• Field of Search: 607/27, 607/2, 607/88, 607/89, 607/96, 607/98, 607/99, 607/100, 607/101, 607/113, 607/115, 606/27, 600/437, 600/439, 600/459, 128/898, 604/19, 604/20, 604/21, 604/22, 601/2, 601/3
• US Class Current: 607/27
• CPC Class Codes: A61B 2017/00084 Temperature
• CPC Class Codes: A61B 2090/374 NMR or MRI
• CPC Class Codes: A61B 34/10 Computer-aided planning, simulation or modelling of surgical operations
• CPC Class Codes: A61N 7/02 Localised ultrasound hyperthermia hyperthermia in general A61F7/00

Abstract

A thermal treatment system including a heat applying element for generating thermal doses for ablating a target mass in a patient, a controller for controlling thermal dose properties of the heat applying element, an imager for providing preliminary images of the target mass and thermal images during the treatment, and a planner for automatically constructing a treatment plan, comprising a series of treatment sites that are each represented by a set of thermal dose properties. The planner automatically constructs the treatment plan based on input information including one or more of a volume of the target mass, a distance from a skin surface of the patient to the target mass, a set of default thermal dose prediction properties, a set of user specified thermal dose prediction properties, physical properties of the heat applying elements, and images provided by the imager. The default thermal dose prediction properties are preferably based on a type of clinical application and include at least one of thermal dose threshold, thermal dose prediction algorithm, maximum allowed energy for each thermal dose, thermal dose duration for each treatment site, cooling time between thermal doses, and electrical properties for the heat applying element. The user specified thermal dose prediction properties preferably include at least one or more of overrides for any default thermal dose prediction properties, treatment site grid density; and thermal dose prediction properties not specified as default thermal dose prediction properties from the group comprised of thermal dose threshold, thermal dose prediction algorithm, maximum allowed energy for each thermal dose, thermal dose duration for each treatment site cooling time between thermal doses, and electrical properties for the heat applying element.

Claims

1. A thermal treatment system, comprising:

a heat applying element for generating a thermal dose used to ablate a target mass in a patient;

a controller for controlling thermal dose properties of the heat applying element;

an imager for providing preliminary images of the target mass;

a planner for automatically constructing a treatment plan, comprising a series of treatment sites that are each represented by a set of thermal dose properties;

wherein the planner automatically constructs the treatment plan based on input information including one or more of;

a volume of the target mass,

a distance from a skin surface of the patient to the target mass,

a set of default thermal dose prediction properties,

a set of user specified thermal dose prediction properties,

physical properties of the heat applying elements, and

images provided by the imager.

2. The treatment system of claim 1, wherein the thermal dose properties translate, at least in part, to electrical and mechanical properties of the heat applying element.

3. The treatment system of claim 1, wherein the default thermal dose prediction properties are based on a type of clinical application and include at least one of:

thermal dose threshold,

thermal dose prediction algorithm,

maximum allowed energy for each thermal dose,

thermal dose duration for each treatment site,

cooling time between thermal doses, and

electrical properties for the heat applying element.

4. The treatment system of claim 1, wherein the user specified thermal close prediction properties include at least one of

overrides for any default thermal dose prediction properties, treatment site grid density, and

thermal dose prediction properties not specified as default thermal dose prediction properties from the group comprised of thermal dose threshold, thermal dose prediction algorithm, maximum allowed energy for each thermal dose, thermal dose duration for each treatment site cooling time between thermal doses, and electrical properties for the heat applying element.

5. The treatment system of claim 1, wherein the treatment plan ensures that the entire target mass is covered by a series of thermal doses so as to obtain a composite thermal dose sufficient to ablate the entire target mass.

6. The treatment system of claim 1, wherein the thermal dose properties are automatically optimized using physiological properties as the optimization criterion.

7. The treatment system of claim 1, wherein the planner limits the thermal dose at each treatment site in order to prevent carbonization or evaporation.

8. The treatment system of claim 1, wherein the planner constructs a predicted thermal dose distribution illustrating the predicted thermal dose contours of each treatment site in the treatment plan.

9. The treatment system of claim 1, further comprising a User Interface (UI) for entering user specified thermal dose prediction properties and for editing the treatment plan once the treatment plan is constructed.

10. The treatment system of claim 1, wherein the treatment plan is constructed in three dimensions.

11. The treatment system of claim 1, further comprising a feedback imager for providing thermal images illustrating the actual thermal dose distribution resulting at each treatment site.

12. The treatment system of claim 11, wherein the imager acts as the feedback imager.

13. The treatment system of claim 1, wherein the heat applying element applies one of the following

ultrasound energy,

laser light energy,

RF energy,

microwave energy, and

electrical energy.

14. A focused ultrasound system, comprising:

a transducer for generating ultrasound energy that results in thermal doses to ablate a target mass in a patient;

an imager for providing preliminary images of the target, and for providing thermal images illustrating an actual thermal dose distribution in the patient; and

a planner for automatically constructing a treatment plan using the preliminary images, the treatment plan comprising a series of treatment sites represented by a set of thermal dose properties used by the controller to control the transducer;

wherein the planner further constructs a predicted thermal dose distribution illustrating the predicted thermal dose contours of each treatment site in the treatment plan;

wherein after a thermal dose is delivered to each treatment site in the treatment plan, the actual thermal dose distribution is compared to the predicted thermal dose distribution to determine remaining untreated locations within the target mass.

15. The focused ultrasound system of claim 14, wherein after a thermal dose is delivered to a treatment site in the treatment plan, the actual thermal dose distribution is compared to the predicted thermal dose distribution to determine changes to the dosing parameters in neighboring sonication sites.

16. The focused ultrasound system of claim 14, wherein the planner automatically evaluates the treatment plan based on the remaining untreated locations and updates the treatment plan to ensure complete ablation of the target mass is achieved by one or more of adding treatment sites, removing treatment sites, modifying existing treatment sites, or leaving the treatment plan unchanged.

17. The focused ultrasound system of claim 14, wherein a user can manually adjust the treatment plan based on the remaining untreated locations.

18. The focused ultrasound system of claim 14, wherein the preliminary images and the thermal images represent three-dimensional data.

19. The focused ultrasound system of claim 14, wherein the predicted thermal dose distribution and actual thermal dose distribution represent three-dimensional data.

20. The focused ultrasonic system of claim 14, wherein the imager further provides outlines of sensitive regions within the patient where ultrasonic waves are not allowed to pass.

21. The focused ultrasonic system of claim 20, wherein the processor uses the outlines in constructing the treatment plan so as to avoid exposing the sensitive regions to ultrasound.

22. The focused ultrasound system of claim 20, wherein the sensitive regions comprise bones, gas, and other sensitive tissues.