Patent Publication Number: US-2021186366-A1

Title: Visualizing a treatment of breast cancer

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to medical devices, and particularly to methods and systems for visualizing a treatment of breast cancer. 
     BACKGROUND OF THE INVENTION 
     Some medical procedures, such as cancer treatment are visualized for improving the quality of the treatment. 
     For example, U.S. Patent application publication 2015/0169836 describes a medical instrument comprising a medical imaging system for acquiring medical image data from an imaging zone and a treatment system for depositing energy into a treatment zone. A processor executing instructions receives a selection of a reference location and one or more anatomical references. The instructions cause the processor to repeatedly: deposit energy into the subject using a treatment system; acquire medical imaging data with the medical imaging system; determine a cumulative dosage data from the medical image data; determine a first registration for the reference location; determine a second registration for the one or more anatomical references; render the medical image, the one or more anatomical references, and the cumulative dosage data in the graphical user interface; and halt the deposition of energy into the subject if a halt command is received from the graphical user interface. 
     U.S. Patent application publication 2015/0082220 describes methods of systems for radiotherapy. In some embodiments, the system includes a carousel for displaying the plurality of images to a user and for receiving an input from the user for selecting one or more images displayed in the carousel. A graphical user interface may be provided for displaying to the user the one or more images selected from the carousel. 
     SUMMARY OF THE INVENTION 
     An embodiment of the present invention that is described herein provides a method that includes, in a medical procedure carried out during a time interval including at least first and second time periods, receiving, for the first time period, a first electrical signal indicative of at least a first position and a first orientation of a hand-held device directing energy to one or more volumetric portions of an organ. A second electrical signal indicative of at least a second position and a second orientation of the hand-held device is received for the second time period. Based on the first and second electrical signals, a cumulative energy applied to at least one of the one or more volumetric portions is estimated. The estimated cumulative energy, of at least one of the one or more volumetric portions, is overlaid on an anatomical image of the organ. 
     In some embodiments, the hand-held device includes an ultrasound (US) transducer that is placed in physical contact with the organ or with a fluid applied to the organ, and receiving the first and second positions and orientations includes receiving the first and second positions and orientations of the US transducer relative to the organ. In other embodiments, at least one of the volumetric portions includes cancerous tissue, and estimating the cumulative energy includes estimating the cumulative energy that is indicative of a treatment applied to the cancerous tissue. In yet other embodiments, the method includes receiving an indication of at least one of (i) a power level of the directed energy and (ii) a spatial distribution of the directed energy applied by the hand-held device during at least one of the first and the second time periods, and estimating the cumulative energy includes assessing the cumulative energy based on the indication. 
     In an embodiment, the method includes holding one or more tissue parameters indicative of one or more properties of respective one or more volumetric portions of the organ, and estimating the cumulative energy includes estimating, based on the one or more tissue parameters, at least one of (i) an attenuation level and (ii) an absorption level that the directed energy undergoes in the respective one or more volumetric portions. In another embodiment, overlaying the estimated cumulative energy includes displaying a pattern depicting evolvement of the estimated cumulative energy over time. 
     In some embodiments, overlaying the estimated cumulative energy includes displaying a marker indicative of whether the estimated cumulative energy matches a specified level. In other embodiments, receiving the first and second electrical signals includes receiving the first and second electrical signals from a position sensor coupled to the hand-held device. 
     There is additionally provided, in accordance with an embodiment of the present invention, a system including a processor and a display. The processor is configured, in a medical procedure carried out during a time interval including at least first and second time periods, to: (a) receive, for the first time period, a first electrical signal indicative of at least a first position and a first orientation of a hand-held device directing energy to one or more volumetric portions of an organ, (b) receive, for the second time period, a second electrical signal indicative of at least a second position and a second orientation of the hand-held device, and (c) estimate, based on the first and second electrical signals, a cumulative energy applied to at least one of the one or more volumetric portions. The display is configured to overlay the estimated cumulative energy, of at least one of the one or more volumetric portions, on an anatomical image of the organ. 
     The present invention will be more fully understood from the following detailed description of the embodiments thereof, taken together with the drawings in which: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic pictorial illustration of a system for treating breast cancer, in accordance with an embodiment of the present invention; 
         FIG. 2A  is a diagram that schematically illustrates an ultrasound-based cancer treatment procedure carried out by applying ultrasound (US) waves to a breast tumor, in accordance with an embodiment of the present invention; 
         FIG. 2B  is a diagram that schematically illustrates a visualization of energy carried by US waves applied to a breast tumor, in accordance with an embodiment of the present invention; and 
         FIG. 3  is a flow chart that schematically illustrates a method for determining cumulative energy applied to volumetric portions of a breast tumor during a cancer treatment procedure, in accordance with embodiments of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     Overview 
     Embodiments of the present invention that are described hereinbelow provide methods and apparatus for visualizing cumulative ultrasound (US) energy applied to breast tissue during a cancer treatment procedure. In some embodiments, a system for treating breast cancer comprises an US transducer, which is configured to apply energy, carried by US waves, to breast tissue having a tumor in one or more volumetric portions thereof. 
     In some embodiments, a magnetic position sensor of a magnetic position tracking system, is coupled to the US transducer and is configured to produce position signals indicative of the position and orientation of the US transducer in a coordinate system of magnetic position tracking system. 
     During the cancer treatment procedure, a physician applies ultrasound energy to one or more volumetric portions of the breast tissue having a known tumor, so as to reduce or eliminate the tumor, e.g., by provoking the immune system to destroy the tumor. 
     In some embodiments, the physician sets the US transducer to apply to the breast tissue predefined parameters of the US waves, such as power, amplitude, and spatial distribution. The physician controls the US transducer to apply the US waves using a predefined amplitude and during a predefined time interval. 
     In some embodiments, the physician may apply the US waves by positioning the US transducer at least at two different positions on the breast skin, referred to herein as first and second positions. In such embodiments, during the time interval, the physician may apply the US waves at the first and second positions during respective first and second time periods of the time interval. 
     In some embodiments, the magnetic position sensor is configured to produce for the first time period, a first electrical signal indicative of a first position and a first orientation of the US transducer directing the US waves to the one or more volumetric portions of the breast tissue. The magnetic position sensor is further configured to produce for the second time period, a second electrical signal indicative of a second position and a second orientation of the US transducer. 
     In some embodiments, the system comprises a processor, which is configured to hold one or more tissue parameters indicative of properties of the tumor, and predefined parameters of the US waves. The processor is configured to estimate or assess, based on the first and second electrical signals and on the aforementioned tumor properties and predefined parameters of the US waves, the cumulative energy applied to one or more volumetric portions of the tumor. 
     In some embodiments, the processor is configured to receive, from a medical imaging system, an anatomical image of at least the tumor, and to display the anatomical image on a display of the system. In some embodiments, the processor is configured to register between coordinate systems of the medical imaging system and the magnetic position tracking system, and to overlay, on the anatomical image, the estimated cumulative energy applied to one or more of the volumetric portions of the tumor. 
     The disclosed techniques improve the quality of cancer treatment procedures by providing the physician with a real-time animation indicative of the cumulative energy applied to one or more volumetric portions of respective tumors. The disclosed techniques assist the physician with applying the specified dose planned for each volumetric portion, and reduce the procedure cycle-time and allocated resources, such as supplementary imaging of the respective tumors during the procedure. 
     System Description 
       FIG. 1  is a schematic pictorial illustration of a system  10  for treating breast cancer, in accordance with an embodiment of the present invention. In some embodiments, system  10  comprises a hand-held device, referred to herein as a device  77 , which is operated by a physician  33  during a breast cancer treatment procedure. 
     In some embodiments, device  77  is configured to direct energy, in the present example the energy is carried by ultrasound (US) waves, to a breast  55  of a patient  11 , so as to reduce or eliminate a known and pre-characterized cancerous tissue, referred to herein as a tumor  66 , in breast  55 . The operation of device  77  is described in detail in  FIG. 2A  below. 
     In an embodiment, physician  33  may apply, between device  77  and the skin of breast  55 , a gel  14  or any other suitable type of fluid, configured to convey the US waves between device  77  and tumor  66  in breast  55 . 
     In some embodiments, a magnetic position sensor  88 , of a magnetic position tracking system described herein, is coupled to device  77 . Magnetic position sensor  88  is configured to produce a position signal indicative of the position and orientation of device  77  in a coordinate system of the magnetic position tracking system. 
     In some embodiments, device  77  is electrically connected, via an electrical cable  46 , to a control console  20 . In an embodiment, console  20  comprises a computer  16 , and user interface (UI) devices, such as but not limited to input devices  23  and a display  18 . Physician  33  may use input devices  23  for controlling the operation of device  77  and other components of system  10 . 
     In some embodiments, computer  16  comprises a driver circuit  41 , which is configured to drive, via a cable  27 , multiple magnetic field-generators of a location pad  36  of the magnetic position tracking system. The magnetic field-generators (e.g., three or four magnetic field-generators in location pad  36 ) are configured to produce alternating magnetic fields, and magnetic position sensor  88  is configured to produce the position signal in response to the alternating magnetic fields. In an embodiment, location pad  36  is placed at a known position external to patient  11  lying on a table  29 , e.g., below the patient torso or at any other suitable position. 
     In some embodiments, computer  16  comprises a processor  22  having suitable front end and interface circuits for receiving anatomical images of breast  55  that are acquired using a suitable medical imaging system, such as but not limited to a computerized tomography (CT) system, a magnetic resonance imaging (MRI) system, or a fluoroscopy system. The front end and interface circuits are further configured for receiving position signals from magnetic position sensor  88 , and for displaying on display  18 , one or more of the anatomical images and additional information that will be described in detail below. 
     In some embodiments, processor  22  typically comprises a general-purpose processor, which is programmed in software to carry out the functions described herein. The software may be downloaded to the computer in electronic form, over a network, for example, or it may, alternatively or additionally, be provided and/or stored on non-transitory tangible media, such as magnetic, optical, or electronic memory. 
     During the cancer treatment procedure physician  33  moves device  77  on the skin of breast  55 , and magnetic position sensor  88  produces, at each position of device  77 , the aforementioned position signal, which is indicative of the present position and orientation of device  77  at the respective position on breast  55 . 
     As described above, processor  22  is configured to display, on display  18 , an anatomical image  12  (e.g., acquired by the CT system) of breast  55  having tumor  66 . 
     In some embodiments, based on the position signal received from magnetic position sensor  88 , processor  22  is configured register between the coordinate systems of the CT system and the magnetic position tracking system, and to overlay the position and orientation of device  77  on anatomical image  12 . 
     This method of position sensing is implemented, for example, in the CARTO™ system, produced by Biosense Webster Inc. (Irvine, Calif.) and is described in detail in U.S. Pat. Nos. 5,391,199, 6,690,963, 6,484,118, 6,239,724, 6,618,612 and 6,332,089, in PCT Patent Publication WO 96/05768, and in U.S. Patent Application Publications 2002/0065455 A1, 2003/0120150 A1 and 2004/0068178 A1, whose disclosures are all incorporated herein by reference. 
     This particular configuration of system  10  is shown by way of example, in order to illustrate certain problems that are addressed by embodiments of the present invention and to demonstrate the application of these embodiments in enhancing the performance of such a system. Embodiments of the present invention, however, are by no means limited to this specific sort of example system, and the principles described herein may similarly be applied to other sorts of medical systems. 
     Visualizing Cumulative Energy Applied to Cancerous Tissue 
       FIG. 2A  is a diagram that schematically illustrates an ultrasound-based cancer treatment procedure carried out by applying ultrasound (US) waves  80  to breast tumor  66 , in accordance with an embodiment of the present invention. 
     In some embodiments, device  77  comprises an US transducer  76 , which is positioned by physician  33  at a position  90  on the skin of breast  55 . Device  77  is configured to direct energy, carried by US waves  80 , to tumor  66  located within breast  55 . Note that US waves  80  have predefined parameters, such as amplitude, and the duration of applying US waves  80  to tumor  66  is predefined in accordance with the procedure plan. 
     In an embodiment, physician  33  may apply at position  90 , between US transducer  76  and the skin, gel  14  or any other suitable type of fluid, which is configured to convey US waves  80  between transducer and tumor  66  within breast  55 . 
     As described in  FIG. 1  above, during the cancer treatment procedure physician  33  moves device  77  on the skin surface of breast  55  and US transducer  76  directs US waves  80  so as to treat tumor  66 . In the example of  FIG. 2A , physician  33  places device  77  at position  90  and processor  22  receives, from one or more magnetic position sensors  88 , the position signal indicative of position  90  and the orientation of device  77 , shown schematically as a dashed line  78 . 
     In some embodiments, processor  22  receives parameters related to US waves  80 . The parameters may comprise a power level of the energy carried by US waves  80 , a spatial distribution of US waves  80 , a time period in which US waves  80  are applied to breast  55  at position  90 , and/or any other suitable parameters related to US waves  80 . 
     As described above, tumor  66  is already characterized before conducting the cancer treatment procedure. In some embodiments, after the characterization of breast  55  and tumor  66 , processor  22  may hold tissue parameters indicative of one or more properties of one or more respective volumetric portions of tumor  66 . The properties of the volumetric portions may comprise tissue density, absorption and/or attenuation of US waves  80 , or any other properties. 
     In some embodiments, processor  22  is configured to estimate, based on the parameters of US waves  80  and the quantified properties of the respective volumetric portions, an attenuation level and an absorption level that US waves  80  undergo in the respective volumetric portions of tumor  66 . 
       FIG. 2B  is a diagram that schematically illustrates a visualization of energy carried by US waves  80  applied to breast tumor  66 , in accordance with an embodiment of the present invention. In some embodiments, the visualization may be carried out on anatomical image  12  that is displayed, for example, on display  18  shown in  FIG. 1  above. 
     In some embodiments, during the cancer treatment procedure processor  22  estimates, for each position such as position  90 , the attenuation level and absorption level of US waves  80  in the respective volumetric portions of tumor  66 . In such embodiments, processor  22  is configured to estimate, based on the estimated attenuation level and absorption level of US waves  80 , a cumulative energy applied to one or more of the volumetric portions of tumor  66 . 
     In some embodiments, processor  22  is configured to overlay, on anatomical image  12 , the estimated cumulative energy applied to one or more of the respective volumetric portions of tumor  66 . 
     In some embodiments, processor  22  may hold one or more thresholds indicative of one or more respective specified levels of the cumulative energy to be applied to the respective volumetric portions of tumor  66 . In other words, for at least one volumetric portion of tumor  66 , processor  22  holds the maximal level of allowed cumulative energy. 
     In some embodiments, processor  22  is configured to overlay on anatomical image  12 , one or more markers indicative of fully irradiated volumetric portions (FIVPs)  99 . Note that FIVPs  99  are indicating that the estimated cumulative energy matches or exceeds the specified level. In the example of  FIG. 2B , processor  22  assigns, to two FIVPs  99  of tumor  66 , a color indicating that the level of the estimated cumulative energy matches the specified level at FIVPs  99 . In other words, when a given volumetric portion of tumor  66  is sufficiently irradiated with US waves  80  in accordance with the treatment plan, processor  22  assigns a color to the given volumetric portion in anatomical image  12 , so that physician  33  may stop applying US waves  80  to that given volumetric portion. 
     In some embodiments, processor  22  is configured to overlay on anatomical image  12 , a pattern depicting real-time or near-real-time, evolvement of the estimated cumulative energy over time. The pattern may appear as animation of colors, or may have any other suitable appearance. 
     In other embodiments, processor  22  may overlay on anatomical image  12 , any other suitable indication that, at a given volumetric portion of tumor  66 , the estimated cumulative energy matches the specified level of cumulative energy. 
     In yet other embodiments, processor  22  may assign a color code indicative of the level of the estimated cumulative energy relative to the specified level of cumulative energy. For example, processor  22  may assign a green color to a volumetric portion of tumor  66  having the estimated cumulative energy substantially lower than the specified level of cumulative energy, a yellow color when the estimated cumulative energy is about 50% of the specified level of cumulative energy, and a red color when the estimated cumulative energy matches the specified level of cumulative energy. Note that physician  33  control device  77  for applying US waves  80  to the volumetric portions of tumor  66  having a known tumor, so as to reduce or eliminate the tumor, e.g., by provoking the immune system of patient  11  to attack tumor  66 , or by over-heating tumor  66 . 
       FIG. 3  is a flow chart that schematically illustrates a method for determining cumulative energy applied to volumetric portions of tumor  66  during a cancer treatment procedure, in accordance with embodiments of the present invention. The method begins at a positioning step  100 , with physician  33  positioning US transducer  76  of device  77  at position  90  on the skin of breast  55 , and applying US waves  80  in accordance with the treatment plan. As described in  FIGS. 1, 2A and 2B  above, physician  33  may apply US waves  80  to one or more positions on breast  55 , in addition to position  90 . 
     At a data receiving step  102 , processor  22  receives data related to US transducer  76  of device  77 . The data may comprise (a) position and orientation of device  77  received from magnetic position sensor  88 , (b) data related to the energy carried by US waves  80 , such as but not limited to the power and spatial distribution thereof, and (c) the time period of applying US waves  80  at the respective positions (e.g., position  90  and additional positions determined by physician  33 ) and conditions described above. 
     In some embodiments, at step  102  processor  22  receives the data in real-time for every position of device  77  on the skin of breast  55 . As described in  FIGS. 1, 2A and 2B  above, processor  22  may hold tissue parameters indicative of one or more properties of respective volumetric portions of tumor  66  that were characterized before starting the cancer treatment procedure. 
     At an estimation step  104 , processor  22  estimates, at least based on the data received at step  102 , the cumulative amount of energy (carried by US waves  80 ) that was applied to the volumetric portions of tumor  66 , at position  90  and at additional positions on breast  55  that were selected by physician  33 . In some embodiments, the estimated cumulative energy is carried out in real-time. 
     At a displaying step  106 , processor overlays, on anatomical image  12 , the estimated cumulative energy applied to tumor  66  by device  77 . As described in  FIGS. 2A and 2B  above, processor  22  displays the estimated cumulative energy applied to one or more volumetric portions of tumor  66 . In some embodiments, processor  22  is configured to display a pattern depicting real-time, or near-real-time, evolvement of the estimated cumulative energy over time. 
     In some embodiments, processor  22  applies color-coding or any other suitable displaying technique, to the one or more volumetric portions represented in anatomical image  12 . In such embodiments, processor  22  provides physician  33  with a visualization of the estimated cumulative energy applied to the respective volumetric portions, relative to the specified level of the cumulative energy as determined in the treatment procedure plan. 
     In an embodiment, processor  22  may display a real-time animation of the evolving colors of the volumetric portions of tumor  66 . In this embodiment, processor  22  assigned the color of FIVP  99  to a given volumetric volume that have reached the specified level of cumulative energy. 
     Although the embodiments described herein mainly address treatment of breast cancer, the methods and systems described herein can also be used in other applications, such as in cancer treatment of any other human organ, and/or in any treatment involving applying energy to any mammalian organ. 
     It will thus be appreciated that the embodiments described above are cited by way of example, and that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, the scope of the present invention includes both combinations and sub-combinations of the various features described hereinabove, as well as variations and modifications thereof which would occur to persons skilled in the art upon reading the foregoing description and which are not disclosed in the prior art. Documents incorporated by reference in the present patent application are to be considered an integral part of the application except that to the extent any terms are defined in these incorporated documents in a manner that conflicts with the definitions made explicitly or implicitly in the present specification, only the definitions in the present specification should be considered.