CN111603204A

CN111603204A - Method and interventional guidance system for providing real-time image guidance for biopsy

Info

Publication number: CN111603204A
Application number: CN201910133764.0A
Authority: CN
Inventors: 胡国蕐; B·王; J·米特拉; L·S·史密斯; D·M·米尔斯; W·李
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 2019-02-22
Filing date: 2019-02-22
Publication date: 2020-09-01

Abstract

A system and method for providing virtual real-time MRI guidance for biopsies external to a conventional MRI scanner is described. MR images and ultrasound images of a region of a patient's body are acquired simultaneously during a pre-biopsy procedure. The respiratory states that the patient may experience during the biopsy are then determined from the acquired ultrasound images, and each respiratory state is associated with a corresponding MR image. The MR images are indexed by their corresponding breathing states. Ultrasound images of the patient are then acquired during the biopsy procedure. The patient's respiratory state is determined from the ultrasound images and the corresponding indexed MR images are displayed.

Description

Method and interventional guidance system for providing real-time image guidance for biopsy

Technical Field

The subject matter disclosed herein relates to the use of ultrasound and magnetic resonance imaging modalities, such as during image-guided breast biopsies.

Background

Image-guided breast biopsy typically involves the use of an imaging procedure, such as ultrasound imaging or Magnetic Resonance Imaging (MRI), to guide a biopsy needle to extract tissue at a suspicious lesion within a patient. Ultrasound imaging provides a high frame rate to track the trajectory of the needle during the biopsy procedure. However, conventional ultrasound imaging has a limited field of view, which can lead to misinterpretation of the location of a suspicious lesion or needle. In contrast, MRI provides higher sensitivity in lesion detection. It also provides three-dimensional positional information and a large field of view. A typical MRI-guided breast biopsy places a patient in a prone position with the patient's breast immobilized by two compression plates and a grid. The grid is used to locate a suspicious lesion and to indicate the insertion point of the biopsy needle. Due to limited access of the patient within the MRI scanner, the patient must be periodically removed from the MRI to reposition the biopsy needle and moved back into the MRI scanner for further imaging. Thus, active visualization of the progress of the biopsy needle or verification of the biopsy site cannot be performed when the patient is outside the MRI scanner. Additionally, breast compression can be very painful for the patient and can lead to false characterization of the lesion type or underestimate the size of the lesion. Unlike MRI-guided breast biopsy, ultrasound-guided breast biopsy places the patient in a supine position and does not require breast compression.

Disclosure of Invention

The following outlines certain embodiments commensurate in scope with the originally claimed subject matter. These embodiments are not intended to limit the scope of the claimed subject matter, but rather only to provide a brief summary of possible embodiments. Indeed, the invention may comprise various forms which may be similar to or different from the embodiments set forth below.

In one embodiment, a method for providing real-time image guidance for a biopsy includes acquiring a Magnetic Resonance (MR) image and a pre-biopsy ultrasound image of an anatomical region of a patient. The MR image and the pre-biopsy ultrasound image are acquired simultaneously over a period of time. The method includes determining a respiratory state of the patient from the pre-biopsy ultrasound image. A respiratory state is associated with each of the MR images or each of a set of MR images. The method further comprises indexing the MR images with their corresponding respiratory states and storing the MR image or each of a set of MR images with their corresponding respective respiratory states.

In another embodiment, a method for providing real-time image guidance for a biopsy includes acquiring a biopsy ultrasound image of an anatomical region of a patient, and determining a biopsy respiratory state from the biopsy ultrasound image. The biopsy respiratory state is identified as the respiratory state of the patient associated with one or more stored MR images of the patient. The method includes retrieving a stored MR image corresponding to the identified respiratory state and displaying the stored MR image corresponding to the identified respiratory state.

In another embodiment, an interventional guidance system includes an ultrasound imaging system configured to acquire a pre-biopsy ultrasound image and a biopsy ultrasound image of an anatomical region of a patient and a processor. The processor is configured to determine one or more respiratory states of the patient from the acquired pre-biopsy ultrasound images, associate the one or more respiratory states with each MR image, index the MR images with their associated respiratory states, and determine a biopsy respiratory state from the biopsy ultrasound images. The biopsy respiratory state is identified as corresponding to one of the respiratory states determined from the pre-biopsy ultrasound images. This in turn determines the MR image or set of MR images acquired from the pre-biopsy scan that correspond to the current respiratory state. Thus, an accurate representation of the position of the anatomical structure at that point in time may be presented or displayed to guide a biopsy procedure, in particular a biopsy needle trajectory to a biopsy target. The processor is also configured to display the MR image corresponding to the identified respiratory state.

Drawings

These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

figure 1 illustrates an embodiment of a combined magnetic resonance and ultrasound imaging system with an MR compatible real-time three-dimensional imaging ultrasound probe in accordance with aspects of the present disclosure;

figure 2 illustrates an alternative embodiment of a combined magnetic resonance and ultrasound imaging system having an MR compatible ultrasound probe with a single continuous shielded cable inserted into the ultrasound system in accordance with aspects of the present disclosure;

figure 3 illustrates an embodiment of an alternative combined magnetic resonance and split ultrasound imaging system arrangement in accordance with aspects of the present disclosure;

fig. 4 illustrates an embodiment of an interventional guidance system according to aspects of the present disclosure; and

fig. 5 illustrates a flow diagram of an embodiment of a combined magnetic resonance and ultrasound image guided biopsy in accordance with aspects of the present disclosure.

Detailed Description

One or more specific embodiments will be described below. In an effort to provide a concise description of these embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.

When introducing elements of various embodiments of the present invention, the articles "a," "an," "the," and "said" are intended to mean that there are one or more of the elements. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements other than the listed elements. Further, any numerical examples in the following discussion are intended to be non-limiting, and thus additional numbers, ranges, and percentages are within the scope of the disclosed embodiments.

As used herein, the term virtual real-time magnetic resonance image(s) "refers to a display of previously acquired MR images, which correspond to the current respiratory state of the patient (as further explained below). Thus, displaying these MR images provides "real-time" MR imaging of the patient, even if the current image modality employed is ultrasound. Systems and processes are described that enable "real-time" MR imaging when another imaging modality, such as ultrasound, is employed by displaying the correct previously acquired MR image or set of MR images that accurately represent the location of anatomical structures within the imaging field of view.

The method relates to direct imaging guidance of a biopsy procedure using virtual real-time magnetic resonance images. In certain implementations discussed herein, imaging and biopsy procedures are performed on a patient's breast without breast compression or the use of a plate to guide the biopsy needle. While certain aspects of the present disclosure focus on imaging guidance of breast biopsy procedures, one of ordinary skill in the art will recognize that the present methods may be applied to other suitable regions of the human body. Image guided biopsy procedures combine MR imaging with real-time ultrasound imaging to provide guidance for the biopsy needle. During the pre-biopsy stage of a breast biopsy procedure, an ultrasound probe acquires ultrasound images of a patient's breast simultaneously with the acquisition of MR images in the MR scanner. The ultrasound probe is MR compatible such that it can be operated simultaneously in the MR scanner while the MR scanner is in operation. The ultrasound images provide a measure of the patient's respiratory state. The concurrently acquired MR images are then indexed (e.g., stored in a table) with the determined respiratory states of the patient such that each respiratory state determined from the ultrasound images has a corresponding MR image. Ultrasound images also facilitate the determination of mathematical transformation functions that can be used to deform acquired MR images to represent the real-time spatial arrangement of a patient's breast during a subsequent biopsy procedure. During the biopsy phase of a breast biopsy procedure, an ultrasound probe acquires ultrasound images of a patient's breast in real time. The ultrasound image is used to identify the current respiratory state of the patient. The processor then accesses stored and pre-acquired MR images from the pre-biopsy stage, which are associated with different respiratory states. The processor then identifies a respiratory state, which may be represented by one or more identifiers from a set of identifiers. The identifier may consist of a set of one or more numbers or parameters that are linked to a unique breathing state. The processor then searches the corresponding indexed pre-biopsy MR image or set of images matching the current respiratory state and displays the images to guide the biopsy needle.

Fig. 1 shows a possible configuration of an MRI system 110 and an ultrasound system 112 suitable for simultaneous image acquisition. An MR compatible probe 114 for use with the MRI system 110 is connected to the ultrasound system 112 in the separate ultrasound control room 104 via a probe cable 116 that passes through a shielding wall 118 of the MRI room 102. The probe cable 116 does not significantly degrade the image quality of the ultrasound system 112 due to the presence of the transmitter and low noise amplifier in the probe handle. Probe components with very low or no ferromagnetic material content are selected for MR compatibility. In addition, the probe 114 is designed to minimize loops in the electronic circuitry to avoid induced currents in the changing magnetic field. The entire probe 114, including the transducer face, housing and cable 116, is encapsulated in a complete electromagnetic interference (EMI) shield to prevent unwanted ultrasonic MRI interference. The transducer face may be covered, for example, by 10-15 micron thick aluminum foil to electrically shield the transducer with negligible impact on acoustic performance.

In another possible configuration of the MRI system 110 and the ultrasound system 112, the MR compatible probe 114 may be hands-free and electronically steerable. The probe 114 may be remotely operated from the control room 104 of the ultrasound system 112 or at another suitable location. The probe 114 may also be secured to the patient's breast via a Velcro (Velcro) strap in a rigid breast restraint structure that allows access by a biopsy needle, or another suitable device that allows simultaneous MR and ultrasound imaging.

Fig. 2 shows another possible configuration of the MRI system 110 and the ultrasound system 112. The MR compatible probe 114 is attached to a single continuous shielded probe cable 216, which probe cable 216 penetrates a wall separating the MR room 102 from the control room 104 or at another suitable location. The shielded probe cable 216 is inserted into the ultrasound system 112 in the control room 104. The electrical shielding of the shielded probe cable 216 may be connected to the shielding wall 118 of the MR room 102 at the penetration location 219 in order to provide complete EMI shielding to reduce unwanted ultrasound-MRI interference.

Fig. 3 shows an alternative split ultrasound system arrangement suitable for simultaneous MR and ultrasound image acquisition. The ultrasound system is separated into an MR compatible front end 313 and a power supply 320 and an ultrasound back end 322, the MR compatible front end 313 being placed in the MR room 102 and the power supply 320 and the ultrasound back end 322 being placed in the ultrasound control room 104. The power source 320 and the ultrasound back end 322 may be separate components or housed together in a single unit 312. The power and digital communication lines pass through the shield wall 118 between the front end 313 and the power supply 320 and the back end 322. An advantage of this system arrangement is that since the ultrasound system has an MR compatible front end 313, a shorter probe cable 316 (e.g., 2-3 meters) is sufficient to connect the probe to the front end. For probes that do not have transmitters and low noise amplifiers integrated in the probe handle, reducing the cable length reduces parasitic loading and thus improves image quality.

Fig. 4 shows a high-level view of components of an interventional guidance system 400, which may be suitable for implementation of the present method. In particular, the method may be implemented as one or more executable routines stored on a memory 404 or data storage component of a processor 402 of the interventional guidance system 400. The illustrated interventional guidance system 400 is in communication with an MRI scanner 406, the MRI scanner 406 being configured to acquire MR images of the patient during the pre-biopsy stage. The MRI scanner may be at any field strength. The interventional guidance system 400 is also in communication with an ultrasound imaging system 408, the ultrasound imaging system 408 being configured to acquire ultrasound images of the patient during a pre-biopsy stage and during a biopsy procedure using an MR compatible probe 410. The processor 402 may be a component of a picture archive system, a dedicated navigation system (as shown in fig. 4), or a portion of an ultrasound imaging system 408, where the ultrasound system 408 functions as or otherwise provides navigation functionality. The processor 402 may store images acquired from an MRI scanner, an ultrasound imaging system, or both. Interventional guidance system 400 may also communicate with biopsy system 414 to provide guidance during a biopsy procedure. We note that the described system and procedure requires two phases in the biopsy procedure, a pre-biopsy phase, where MR and ultrasound imaging occur simultaneously, and an actual biopsy phase or procedure, where ultrasound imaging and needle insertion occur.

Figure 5 shows a flowchart of a method of providing virtual real-time magnetic resonance images for direct imaging guidance of a breast biopsy of a patient, such as a patient in a supine position. The method comprises two imaging phases: (1) pre-biopsy stage (i.e., steps 502 to 508); and (2) a biopsy phase (steps 510 to 524). The steps of the pre-biopsy phase may occur at any time prior to the biopsy phase and may occur at different locations or at the same location. For example, the pre-biopsy stage may be performed in an MR scanner, and the biopsy procedure may be performed outside the MR scanner, such as in a standard clinical examination room.

During the pre-biopsy phase, in step 502, a three-dimensional MR image and a true three-dimensional (four-dimensional) ultrasound image of the patient's breast are acquired simultaneously. The MR image and each ultrasound image need not be perfectly aligned in time. If the images are not temporally aligned, techniques such as temporal interpolation may be used to substantially align or substantially link the images. MR images can be acquired without breast compression or with limited compression or positioning. For example, in one embodiment, the MR system uses flexible, conformable, multi-element, lightweight coils during acquisition of MR images. At each time frame, one or more endogenous fiducial markers are identified in the ultrasound image in step 504. For example, endogenous fiducial markers may include blood vessels, structural anatomy of the breast (e.g., chest wall), or the suspected lesion itself.

In step 506, the change in position or shape in the ultrasound image of the identified endogenous fiducial marker of step 504 is used to determine the respiratory state at each time frame of the ultrasound image. The respiratory state represents a possible respiratory state that the patient may experience during the biopsy procedure for both the pre-biopsy and biopsy phases. For example, the breathing state may include inhalation, exhalation, brief breath hold, irregular breath, or any sub-state of the breathing state. In step 508, each determined respiratory state or sub-state is then associated with one or more acquired MR images. A table or index of the determined respiratory states and their corresponding MR images is created.

During the biopsy stage, the ultrasound probe may be similar to or the same as the ultrasound probe used to acquire ultrasound images during the pre-biopsy stage. In one embodiment, the ultrasound probe may be manually manipulated during the biopsy stage. Manual manipulation of the ultrasound probe will provide a more optimal visualization of the biopsy target and the biopsy needle in the same image. In another embodiment, the ultrasound probe may be electronically or remotely operated during the pre-biopsy stage and the biopsy stage, electronically operated during the pre-biopsy stage, manually operated during the biopsy stage, or manually operated during both the pre-biopsy stage and the biopsy stage.

In step 510, a three-dimensional ultrasound image of the patient's breast is acquired in real-time. In step 512, the four-dimensional ultrasound image is used to locate the same endogenous fiducial markers identified in step 504. In step 514, the position or spatial information of the endogenous fiducial markers in the ultrasound image is used to determine the current respiratory state of the patient. In step 516, an index or table of previously determined respiratory states and their corresponding MR images is accessed and the MR image associated with the current respiratory state of the patient is retrieved. In step 518, a non-rigid body transformation is performed on the MR image retrieved in step 516. The non-rigid body transformation matches the positional state of the patient's breast during the pre-biopsy stage of the procedure with the current positional state of the patient's breast. For example, breast contours or endogenous fiducial markers in the MR and ultrasound images are matched. Therefore, the MR image is deformed to fit the ultrasound image.

This transformation of the MR image provides an accurate representation of the shape and position of the patient's breast during the biopsy procedure. For each set of MR images corresponding to the respiratory state determined during the pre-biopsy phase of the procedure, a non-rigid transformation of the MR images may be performed at any time prior to insertion of the biopsy needle into the patient. This provides an accurate mapping of the location of the patient's breast and the tissue within the patient's breast (e.g., suspicious lesions, arteries, veins, fat layers, and muscle layers). If the position of the patient's breast changes during the biopsy procedure (e.g., during needle insertion), a non-rigid transformation can be reapplied to each set of MR images to provide accurate, updated images with minimal computational overhead.

The respiratory state matching steps 512 to 516 and the deformable registration step 518 may be represented by a single mathematical transfer function or separate mathematical transformation functions. For example, the mathematical transformation function may represent a mapping of one respiratory state to another respiratory state, a mapping of one positional state of a deformable anatomical structure (e.g., a breast) to another positional state, or a combination of both. One of ordinary skill in the art will recognize that the mathematical transformation function may be any suitable geometric operation used with anatomical landmarks observed in ultrasound and MR images.

In step 520, the transformed MR image may be displayed to provide an accurate, real-time representation of the location of the suspicious lesion and surrounding anatomical details of the breast to guide the biopsy needle. However, if no MR image corresponding to the current respiratory state of the patient is available, a signal such as a red dot may be displayed.

In step 522, the position of the biopsy needle may be derived from the real-time ultrasound image or an external position marker on the biopsy needle holder. For example, the external position marker may include an infrared sensor, a magnetoresistive sensor, or other suitable device. The location of the biopsy needle may then be overlaid onto the displayed MR image. To ensure the accuracy of the overlay, the MR image reference frame and the biopsy needle reference frame may be calibrated. For example, an infrared sensor on the biopsy needle may be used to identify the location of the biopsy needle tip and the orientation and trajectory of the biopsy needle. A simple calibration of the position and angle of the biopsy needle tip is performed to align and register the MR image reference frame to the reference frame of the biopsy needle.

In step 524, completion of the biopsy is determined. If it is determined that the biopsy of the suspicious lesion has been successfully completed, the procedure terminates. However, if the biopsy is determined to be incomplete, the imaging and guidance procedure may continue to be performed until it is determined that the biopsy of the suspicious lesion has been successfully completed.

While the above-described embodiment performs the procedure with the patient in a supine position, those skilled in the art will recognize that the procedure is not limited to such a position for the patient. The procedure may be performed on a patient in a prone position. For example, the procedure may require the use of a support structure to allow the patient's breasts to be suspended while the patient is in a prone position. In addition, a corresponding MRI receiver coil tailored for the breast may be required.

Technical effects of the present disclosure include providing virtual real-time MRI guidance for breast biopsies external to a conventional MRI scanner. This allows for active visualization of the biopsy needle progress or verification of the patient biopsy site outside the MRI scanner. The biopsy and imaging procedure allows the patient to be in a more comfortable supine position than in a prone position. In addition, the procedure may be performed without the need for breast compression or the use of a plate to guide the biopsy needle.

This written description uses examples to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The scope of patentability is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.

Claims

1. A method for providing real-time image guidance for a biopsy, comprising:

acquiring a plurality of MR images of an anatomical region of a patient;

acquiring a plurality of pre-biopsy ultrasound images of the anatomical region, wherein the MR image and the pre-biopsy ultrasound images are obtained simultaneously over a scan duration;

determining a plurality of respiratory states of the patient from the pre-biopsy ultrasound images, wherein each respiratory state is associated with one or more MR images;

indexing the MR images with their corresponding respective respiratory states; and

storing the MR images with the corresponding respective respiratory states of the MR images.

2. The method of claim 1, comprising identifying endogenous fiducial markers in the pre-biopsy ultrasound image.

3. The method of claim 2, wherein determining the plurality of respiratory states of the patient from the pre-biopsy ultrasound images is based on a change in position or a change in shape of the anatomical region relative to the identified endogenous fiducial marker.

4. The method of claim 1, wherein the anatomical region of the patient comprises a breast of the patient.

5. The method of claim 4, wherein the MR image and the pre-biopsy ultrasound image are acquired without breast compression.

6. The method of claim 1, wherein the plurality of respiratory states comprise exhalation, inhalation, brief breath hold, or irregular breathing.

7. The method of claim 1, wherein the respective respiratory states are associated with one or more MR images by timely associating the MR images substantially with the pre-biopsy ultrasound images over the scan duration.

8. The method of claim 1, wherein the patient is in a supine position.

9. A method for providing real-time image guidance for a biopsy, comprising:

acquiring a plurality of biopsy ultrasound images of an anatomical region of a patient;

determining a biopsy respiratory state from the biopsy ultrasound image, wherein the biopsy respiratory state is identified as a respiratory state of the patient associated with one or more stored MR images of the patient;

retrieving the stored MR image corresponding to the identified respiratory state; and

displaying the stored MR image corresponding to the identified respiratory state.

10. The method of claim 9, comprising deforming the stored MR image to substantially match the structure of the anatomical region of the patient during the identified biopsy respiratory state.

11. The method of claim 9, comprising displaying a location of a biopsy needle on the displayed MR image.

12. The method of claim 11, wherein the location of the biopsy needle is displayed by identifying a location or orientation of the biopsy needle using an infrared sensor or a magneto-resistive sensor.

13. An interventional guidance system, comprising:

an ultrasound imaging system configured to acquire a pre-biopsy ultrasound image and a biopsy ultrasound image of an anatomical region of the patient; and

a processor configured to:

determining one or more respiratory states of the patient from the pre-biopsy ultrasound images;

correlating the one or more respiratory states with one or more MR images;

indexing the MR images with corresponding respiratory states;

determining a biopsy respiratory state from the biopsy ultrasound image, wherein the biopsy respiratory state is identified as one of the respiratory states associated with the one or more MR images; and

displaying the MR image corresponding to the identified respiratory state.

14. The interventional guidance system of claim 13, wherein the interventional guidance system is in communication with an MRI scanner configured to acquire the one or more MR images of the anatomical region of the patient.

15. The interventional guidance system of claim 13, comprising a biopsy needle sensor, wherein the processor is configured to display a location of the biopsy needle on the displayed MR image.

16. The interventional guidance system of claim 13, wherein the biopsy needle comprises an infrared sensor or a magneto-resistive sensor for tracking a position or orientation of the biopsy needle.

17. The interventional guidance system of claim 13, wherein the anatomical region of the patient includes a breast of the patient, and the MR image, the pre-biopsy ultrasound image, and the biopsy ultrasound image are acquired without breast compression.

18. The interventional guidance system of claim 13, wherein the ultrasound imaging system comprises an MR compatible ultrasound probe.

19. The interventional guidance system of claim 13, wherein the processor is configured to deform the MR image during the identified biopsy respiratory state to fit the structure of the anatomical region of the patient.

20. The intervention guidance system of claim 13, wherein the processor is configured to identify endogenous fiducial markers from the pre-biopsy and biopsy ultrasound images.