Method and system for biopsy needle reconstruction error assessment

Abstract

The present invention provides a method and system for reconstruction error assessment of an interventional tool used in an image-guided interventional procedure. In one example, an error model based on a target lesion location within a tissue, one or more interventional tool parameters, and imaging system parameters can be used to estimate the expected reconstruction error of the interventional tool. In another example, when the interventional tool is within the tissue, the expected reconstruction error together with the observed tool shape and size can be used to infer the actual tool position and shape within the tissue.

Description

Technical Field

[0001] Embodiments of the subject matter disclosed herein relate to mammography and mammography-driven interventional procedures such as biopsy procedures, and more particularly to evaluating image reconstruction errors during digital breast tomosynthesis (DBT)-guided breast interventional procedures using a needle-shaped interventional tool, such as a needle used in a biopsy procedure. Background Art

[0002] Mammography is a medical imaging procedure for detecting one or more tumors of the breast. Based on mammographic imaging, an interventional procedure can be performed to reach the tumor area and obtain a biopsy sample of the relevant breast tissue for further analysis, or a hook is placed in an appropriate position for later surgery or local cryoablation. During the mammographic procedure, the breast is compressed by a compression paddle and positioned for the interventional procedure. The location of the target tissue (e.g., lesions, microcalcifications, etc.) is then identified based on a mammographic imaging procedure such as digital breast tomosynthesis (DBT). For example, during DBT, a scout image (where the x-ray tube is in a midline position perpendicular to the detector) and multiple projection images (where the x-ray tube moves from the midline in both positive and negative directions to an arc of various angles within a set angle) are obtained. The projection images are reconstructed to obtain a DBT volume rendering of the breast. Then, the target position within the region of interest (ROI) can be selected based on the acquired DBT volume. In the biopsy procedure, when the target is selected, a biopsy tool is inserted into the breast, and a portion of the target tissue is removed with the biopsy tool to obtain a biopsy sample. To improve biopsy accuracy, assessment of biopsy tool position is needed. Tool position assessment may be needed for other interventional procedures (besides breast biopsy) that require positioning of interventional tools, such as but not limited to cryoablation, hook placement, etc. Summary of the invention

[0003] In one embodiment, a method for an x-ray system includes: performing a digital breast tomosynthesis scan of a compressed breast with the x-ray system and generating tomosynthesis scan data; reconstructing an image of the compressed breast based on the tomosynthesis scan data; and determining an expected reconstruction error of an interventional tool based on an error model modeled based on an acquisition geometry of the x-ray system and interventional tool parameters; wherein the interventional tool parameters include a tool length, a tool tip diameter, a tool orientation, and a tool tip position derived from one or more of a selected target position in the reconstructed image and a robotically returned tip position determined based on feedback from a robotic system coupled to the x-ray system.

[0004] In this way, by determining the reconstruction error of the interventional tool, the accuracy of the assessment of the tool position in the reconstructed image can be improved.Therefore, the efficiency and accuracy of the interventional procedure can be increased, and patient care can be improved.

[0005] It should be understood that the above brief description is provided to introduce in a simplified form selected concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is solely defined by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The present disclosure will be better understood by reading the following description of non-limiting embodiments with reference to the accompanying drawings, in which:

[0007] Figure 1A is a high-level block diagram illustrating a schematic diagram for assessing the location of a tool within tissue according to an embodiment of the present disclosure.

[0008] Figure 1B is a schematic diagram of a mammography system for performing digital breast tomosynthesis (DBT) according to an embodiment of the present disclosure;

[0009] Figure 1C According to the embodiments of the present disclosure, Figure 1B A schematic diagram of a biopsy device for use with a mammographic system;

[0010] Figure 1D According to the embodiments of the present disclosure, Figure 1C Schematic diagram of a biopsy needle used with a biopsy device;

[0011] Figure 2 is a high-level flow chart illustrating a method for selecting a biopsy needle for performing a DBT-guided biopsy procedure according to an embodiment of the present disclosure;

[0012] Figure 3A is a high-level flow chart illustrating a method for determining a biopsy needle reconstruction error prior to performing a DBT-guided biopsy procedure according to an embodiment of the present disclosure;

[0013] Figure 3B is a block diagram illustrating an error model for determining a reconstruction error according to an embodiment of the present disclosure;

[0014] Figure 4 shows an exemplary set of data tables including reconstruction error data according to an embodiment of the present disclosure;

[0015] Figure 5is a schematic diagram of an exemplary reconstruction error of a biopsy needle according to an embodiment of the present disclosure;

[0016] Figure 6 is a schematic diagram of another exemplary reconstruction error of a biopsy needle according to an embodiment of the present disclosure;

[0017] Fig. 7A is a high-level flow chart illustrating a method for performing a DBT-guided biopsy procedure according to an embodiment of the present disclosure;

[0018] Figure 7B yes Fig. 7A Continuation of ;

[0019] Figure 7C Shown are a set of exemplary reconstructed images representing exemplary DBT volumes used for target selection during a DBT-guided procedure.

[0020] Figure 8 is a high-level flow chart illustrating a method for determining reconstruction error of a biopsy needle and identifying needle tip location during a DBT-guided biopsy procedure according to an embodiment of the present disclosure; and

[0021] Fig. 9 is a schematic diagram of exemplary reconstruction errors of a biopsy needle in a pre-fired position according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0022] The following description relates to various embodiments of interventional procedures guided by digital breast tomosynthesis (DBT). DBT is an imaging technique for generating cross-sectional images of the breast with high in-plane resolution. DBT can be performed by utilizing an x-ray mammography system. Specifically, during DBT, the breast is compressed, and an x-ray source can be rotated around the breast in a certain angular range in positive and negative directions from a neutral position, and a low-dose x-ray projection image of the breast at each angle can be obtained at a detector. The projection images are then reconstructed into slice images of the breast volume along the z direction. The rotation range of the x-ray system of DBT can vary depending on the manufacturing configuration, and can be in the range of approximately ±11 degrees to ±60 degrees. The rotation range of the x-ray system is also referred to as the angular range of the x-ray system. The resolution of the reconstructed image along the z-axis direction of the imaging volume can be based on the angular range. For example, for a DBT system with a narrower angular range, the z resolution may be lower.

[0023] During a DBT-guided interventional procedure, a tomosynthesis reconstruction image of the relevant breast is first obtained, and a target position (e.g., the position of a lesion) within a region of interest (ROI) is identified by the user. Then the interventional tool and the biopsy gun (e.g., the interventional tool holder) of the interventional device are adjusted so that when the interventional tool is inserted, the interventional tool is in a desired pre-fire position relative to the selected target position. In the case of inserting the interventional tool, another set of tomosynthesis images can be reconstructed to evaluate the current position of the interventional tool relative to the target position. However, due to the limited angular range of the x-ray system, the depth resolution of tomosynthesis along the z direction is low. Specifically, when performing an interventional procedure with a vertical approach, in which the interventional tool is inserted vertically into the breast (e.g., to obtain a portion of the relevant tissue), the resolution of the interventional tool in the reconstructed image along the z direction is low, and thus leads to a reconstruction error of the interventional tool in the tomosynthesis image. An exemplary reconstruction error of the interventional tool is "leakage" in the z direction. For example, when the actual tool depth may be small, the tool may be visible in a larger number of reconstructed image slices, thereby erroneously indicating a larger tool depth. This leakage phenomenon may make it difficult to identify the actual tool tip position, which is used to determine the relationship of the tool's pre-fire position to the target position. More generally, it is important to the success of the procedure to be able to retrieve the actual tool tip position at any step to determine whether the tool is correctly positioned relative to the target position.

[0024] The inventors herein have identified the above problems, and have also identified that reconstruction errors are based on one or more tool parameters and target position parameters in addition to acquisition system angular rotation. Therefore, methods and systems are provided herein for solving at least some of the above problems. In one example, a method for an x-ray system includes: performing a digital breast tomosynthesis scan of a compressed breast with an x-ray system, and generating tomosynthesis scan data; reconstructing an image of the compressed breast based on the tomosynthesis scan data; and determining an expected reconstruction error of an interventional tool based on an error model modeled based on a selected target position in the reconstructed image, an angular rotation range of the x-ray system, and interventional tool parameters.

[0025] Thus, prior to inserting the tool, an expected reconstruction error may be determined based on an error model based on one or more of tool parameters, position parameters, and acquisition system parameters. Additionally, the reconstruction error may be provided to a user, who may then determine whether the reconstruction error is acceptable or whether a different interventional tool should be used for the biopsy. Evaluation of the reconstruction error of the interventional tool and determination of the actual tool tip position may improve the accuracy of the interventional procedure and reduce the number of repetitions of the procedure that may need to be performed to obtain target tissue.

[0026] In addition, when a tool is selected and moved to a pre-fire position, a pre-fire tomosynthesis image of the tool in the pre-fire position can be obtained. Based on the tool volume observed in the pre-fire image and the expected tool volume determined according to the error model, the amount of bending of the tool tip during insertion can be determined. For example, during the insertion of the tool into the pre-fire position, the tool trajectory may not be linear, and therefore the tool tip may not reach the desired pre-fire position. The comparison of the expected tool volume with the observed tool volume can indicate whether the tool has moved away from its target path during insertion. In addition, when there is no bending, the expected observed tool volume matches the expected tool volume (i.e., the volumes overlap highly).

[0027] In addition, based on the observed tool leakage (from the observed tool volume) and the expected tool leakage (from the expected tool volume) in the reconstructed volume, the actual position of the tool tip in the DBT volume can be determined. The determination of the actual tool tip can enable the user to evaluate the actual position of the tool tip relative to the target lesion location and further determine whether the tool is positioned in the desired position so that the tool penetrates the target tissue when fired.

[0028] In addition to evaluating the tool tip position in the pre-fire stage, the error model may also be used to evaluate the tool tip position in the post-fire stage after the tool is fired. For example, a post-fire tomosynthesis image of the tool in the post-fire position may be obtained, and based on the tool volume observed in the post-fire image and the expected tool volume determined according to the error model, the tool tip position in the post-fire stage may be evaluated.

[0029] Go to Figure 1A , which is a block diagram showing a high-level schematic diagram 1000 for assessing the position of an interventional tool within tissue (such as compressed breast tissue) during a DBT-guided interventional procedure. Specifically, the schematic diagram 1000 shows an inference x-ray system (e.g., Figure 1B The actual tool position in the real physical space 1010 (such as the physical volume of compressed tissue between the compression paddle and the detector surface) of the x-ray system 100. Figure 1B , 1C The systems and components of 1D and 1D describe method 1000, but it should be understood that other systems and components can be used to implement the process in the schematic diagram without departing from the scope of the present disclosure.

[0030] The interventional tool may be a mammographic interventional tool, such as a biopsy needle, a hook wire, an ablation needle, etc. During an image-guided mammographic interventional procedure (such as DBT-guided biopsy, hook wire positioning, cryoablation, etc.), it is desirable to assess the actual position of the tool in real physical space in order to determine the positional relationship of the tool relative to the target tissue to be extracted. As described above, when the tool is imaged within the tissue (particularly with DBT imaging), due to the low resolution of the image reconstruction in the z direction (which is caused by the limited angular range of rotation of the x-ray source), the tool appears in a greater number of image slices (z-plane slices) than in real physical space, and therefore the actual tool position may need to be inferred.

[0031] An exemplary theoretical tool shape and position is shown at 1012. In one example, the theoretical tool shape and position may be determined based on one or more inputs. In one example, the theoretical tool shape and position may be determined based on user input. For example, based on a user clicking on a desired portion of an image slice from a first plurality of DBT images of the tissue (with or without the tool), the spatial coordinates (X x y ... 目标 , Y 目标 , Z 目标 ). The coordinates can be used to determine the theoretical tool position and shape within the real physical space 1010. Figure 7C An exemplary determination of target position coordinates is discussed in . In another example, position feedback from a robotic system of an interventional tool within tissue (referred to herein as the tip position returned by the robot) can be used to obtain a theoretical tool position and shape. For example, during a biopsy, a biopsy needle holder control system can also calculate the needle tip position based on sensor data from a robotic system coupled to the biopsy needle holder control system. Figure 8 An exemplary determination of a tip position for robot return is discussed. In yet another example, when a smart tool is used, one or more sensors within the tool may return the tool position within tissue as desired.

[0032] The theoretical tool shape and position 1012 can then be used to calculate the expected tool shape and position 1014 in the image space 1020. The image space 1020 is a reconstructed DBT volume obtained from a plurality of reconstructed images from a DBT acquisition. Thus, the theoretical tool shape and position 1012 can be used to assess how the tool will appear (position and shape) in the reconstructed DBT image volume. Specifically, an error model (such as relative to Figure 3BThe error model 360 described above is used to calculate the expected tool shape and position in the image space 1020. The error model can be stored in the memory of the imaging processor of the x-ray system, and based on one or more of the tool diameter, tool length, theoretical tool shape and position, source-to-image distance, and acquisition system range, the error model can estimate the expected reconstruction error of the reconstructed tool image. The expected tool shape and position is then calculated based on the expected reconstruction error. In this way, the expected tool shape and position are calculated based on the theoretical tool shape and position and the error model.

[0033] For example, an expected tool shape and position and an expected reconstruction error calculated according to an error model may be determined before inserting the interventional tool into tissue, and the expected reconstruction error, i.e., the expected tool shape and position, may be provided to the user via a display portion of a user interface of the x-ray system. In addition, one or more interventional tools that may produce a smaller reconstruction error than the currently selected interventional tool may be provided to the user via the interface. The one or more interventional tools with a smaller expected reconstruction error may be selected from an interventional tool reconstruction error database, such as a database of interventional tool reconstruction errors. Figure 4 The user can then use the expected reconstruction error to determine whether to continue using the currently selected interventional tool or to use a different tool with a smaller reconstruction error.

[0034] Additionally, after the tool is inserted into the tissue, the observed tool shape and position may be determined from the DBT reconstructed image volume of the tissue with the tool 1016. For example, where the tool is positioned within the tissue, a tomosynthesis scan may be performed to obtain a second plurality of DBT images of the tissue in which the tool is positioned. The observed tool shape and position may then be determined from the DBT reconstructed volume obtained from the second plurality of DBT images 1016.

[0035] The expected tool shape and position 1014 in the image space 1020 and the observed tool shape and position 1016 in the image space 1020 are compared with the image processor as shown at 1018. In one example, the expected tool shape and position 1014 in the image space 1020 and the observed tool shape and position 1016 can be compared using visual image processing descriptors.

[0036] Next, the processor may evaluate whether the expected tool shape and position matches the observed tool shape and position (as shown at 1030). If the theoretical tool shape is the same as the expected tool shape, and if the theoretical tool position is the same as the expected tool position (i.e., the answer at 1030 is yes), it may be determined that no deformation or bending of the tool occurred during insertion of the tool into the tissue (as shown at 1032). However, if the theoretical tool shape or position does not match the expected tool shape or position (i.e., the answer at 1030 is no), it may be determined that the tool has bent and / or displaced in real space during insertion / movement within the tissue (as shown at 1036).

[0037] If the comparison indicates that there is no deformation or bending of the tool during insertion / movement of the tool into the tissue, the error model (and therefore the expected tool shape and position) can be used to infer the actual tool position and shape within the tissue (i.e., the actual tool position and shape in actual physical space), as shown at 1034.

[0038] If the comparison indicates that the tool has been bent and / or shifted in space, the expected tool shape and position may be compensated for the bending (e.g., the expected tool shape and position may be compensated to match the observed tool shape and position). The actual tool shape and position may then be inferred from the compensated expected tool shape and position and the error model, as shown at 1038.

[0039] The inferred tool shape and position 1022 (from 1038 or 1034) may then be compared to the theoretical tool shape and position (as shown at 1040) to assess whether the inserted tool is in the desired position relative to the target tissue location.

[0040] In this way, the error model along with the expected tool shape and position and the observed tool shape and position can be used to assess the actual shape and position of the tool within the tissue.

[0041] In the following description, exemplary embodiments of the present invention are described as exemplary interventional procedures with respect to biopsy procedures, thereby using a biopsy needle as an exemplary interventional tool. It should be noted that the present invention can be implemented with respect to other interventional procedures and corresponding interventional tools. Interventional procedures may include, but are not limited to, hook wire positioning and cryoablation procedures. Interventional tools may include, but are not limited to, hook wires for hook wire positioning and probes for cryoablation.

[0042] An exemplary x-ray system that can be used for DBT-guided biopsy is Figure 1B Shown in. Figure 1C and Figure 1D An exemplary biopsy device and biopsy needle that can be used for DBT-guided biopsy are shown. An exemplary method for selecting a biopsy needle based on reconstruction error is shown in Figure 2 An exemplary method for determining reconstruction error and an exemplary error model for determining reconstruction error prior to needle insertion are shown in Figure 3A and Figure 3B . Briefly, a reconstruction error model is stored in a memory of an imaging processor of an x-ray system, and based on one or more of a needle diameter, a needle length, a target distance from a detector, and an acquisition system geometry, the reconstruction error model can estimate an expected reconstruction error that indicates the amount of leakage of the reconstructed needle image along the z-direction. In addition, the reconstruction error model can be modeled so that the expected reconstruction error can be estimated for any type of interventional tool (e.g., hook wire, ablation needle, etc.) and / or various models of the same interventional tool type. The expected reconstruction error can be provided to the user before the needle is inserted into the tissue of interest to a pre-fire position. Thus, the user can determine whether a biopsy can be performed using the current needle or a different needle, which can improve the accuracy and efficiency of the biopsy procedure. In one embodiment, determining the expected reconstruction error of a biopsy needle may include utilizing a reconstruction error table. A set of exemplary reconstruction error data tables are provided in Figure 4 A schematic diagram of the reconstruction error of needles with different needle lengths and diameters is shown in Figure 5 and Figure 6 In addition, an advanced method for performing DBT-guided biopsy using expected reconstruction error to estimate needle position within a compressed breast is presented in Fig. 7A and Figure 7B Shown in. Figure 7C Exemplary selection of target locations for biopsy in a DBT reconstructed volume is discussed. Figure 8 Details of determining the one or more needle parameters are described, including actual needle tip position and needle bending as the needle is inserted into a compressed breast. An exemplary schematic diagram of needle bending during insertion is shown in FIG. Fig. 9 It should be understood that the methods and systems described herein are applicable to evaluating any position (pre-fire position, post-fire position, etc.) of any interventional tool (e.g., hook wire, ablation needle, ablation probe, biopsy needle, etc.) inserted into tissue. Figure 1A A high-level block diagram for assessing the location of tools within an organization is shown.

[0043] See also Figure 1B, a mammography system 100 for performing mammography procedures is shown, according to an exemplary embodiment, which includes an x-ray system 10. The x-ray system 10 can be a tomosynthesis system, such as a digital breast tomosynthesis ("DBT") system. In addition, the x-ray system 10 can be used to perform one or more procedures, including digital tomosynthesis imaging and DBT-guided interventional procedures such as DBT-guided breast biopsy. In addition, the x-ray system 10 can be used to perform one or more of dual-energy CESM procedures, contrast-enhanced DBT (CE-DBT) diagnostic procedures, and interventional stereotactic procedures. In addition, the x-ray system 10 can be used to perform one or more image-guided interventional procedures, including but not limited to image-guided hook-wire positioning and image-guided cryoablation.

[0044] The X-ray system 10 includes a support structure 42 to which a radiation source 16, a radiation detector 18, and a collimator 20 are attached. The radiation source 16 is housed in a gantry 15 that is movably coupled to the support structure 42. Specifically, the gantry 15 can be mounted to the support structure 42 so that the gantry 15 including the radiation source 16 can rotate about an axis 58 relative to the radiation detector 18. The rotation angle range of the gantry 15 that houses the radiation source 16 indicates that the rotation angle range is up to a desired angle in any direction around the axis 58. For example, the rotation angle range of the radiation source 16 may be -θ to +θ, where θ may make the angle range a limited angle range of less than 360 degrees. An exemplary x-ray system may have an angle range of ±11 degrees, which may allow the gantry to rotate from -11 degrees to +11 degrees (i.e., rotation of the radiation source) around the rotation axis of the gantry. The angular range may vary according to manufacturing specifications. For example, the angular range of a DBT system may be approximately ±11 degrees to ±60 degrees, depending on the manufacturing specifications.

[0045] The radiation source 16 is directed toward the volume or object to be imaged and is configured to emit radiation rays at a desired time and acquire one or more images. The radiation detector 18 is configured to receive the radiation rays via the surface 24. The detector 18 can be any of a variety of different detectors, such as an X-ray detector, a digital radiography detector, or a flat panel detector. The collimator 20 is disposed adjacent to the radiation source 16 and is configured to adjust the irradiation area of ​​the subject.

[0046] In some exemplary embodiments, the system 10 may also include a patient shield 36 mounted to the radiation source 16 via a mask rail 38 so that a body part (e.g., head) of the patient is not directly exposed to the radiation. The system 10 may also include a compression paddle 40 that may be capable of moving upward and downward relative to the support structure along a vertical axis 60. Thus, the compression paddle 40 may be adjusted to be positioned closer to the radiation detector 18 by moving the compression paddle 40 downward toward the detector 18, and the distance between the detector 18 and the compression paddle 40 may be increased by moving the compression paddle upward away from the detector along the vertical axis 60. The movement of the compression paddle 40 may be adjusted by a user via a compression paddle actuator (not shown) included in the X-ray system 10. The compression paddle 40 may hold a body part (such as a breast) in a suitable position against the surface 24 of the radiation detector 18. The compression paddle 40 may compress the body part and hold the body part stationary in a suitable position while optionally providing a hole to allow insertion of a biopsy needle, such as a core needle or a vacuum-assisted core needle. Thus, compression paddle 40 can be used to compress the body part to minimize the thickness through which x-rays pass and help reduce movement of the body part due to patient movement. X-ray system 10 can also include a subject support (not shown) on which the body part can be positioned.

[0047] The mammography system 100 may also include a workstation 43 including a controller 44 including a memory and at least one processor. The controller 44 may be communicatively coupled to one or more components of the X-ray system 10, including one or more of the radiation source 16, the radiation detector 18, the compression paddle 40, and the biopsy device. In one exemplary embodiment, communication between the controller and the X-ray system 10 may occur via a wireless communication system. In other exemplary embodiments, the controller 44 may be in electrical communication with one or more components of the X-ray system via a cable 47. Additionally, in one exemplary embodiment, as shown in FIG. Figure 1B As shown, the controller 44 is integrated into the workstation 43. In other exemplary embodiments, the controller 44 may be integrated into one or more of the various components of the system 10 disclosed above. In addition, the controller 44 may include processing circuitry that executes stored program logic, and may be any of a variety of computers, processors, controllers, or combinations thereof that are usable and compatible with various types of equipment and devices used in the X-ray system 10.

[0048] Workstation 43 may include radiation shielding 48 that protects an operator of system 10 from radiation rays emitted by radiation source 16. Workstation 43 may also include a display 50, keyboard 52, mouse 54, and / or other suitable user input devices that facilitate control of system 10 via user interface 56.

[0049] Through its processor and controller, the controller 44 can regulate the operation and function of the X-ray system 10. For example, the controller 44 can provide timing control regarding when the X-ray source 16 emits X-rays, and can also regulate how the detector 18 reads and transmits information or signals after the X-rays hit the detector 18, and how the X-ray source 16 and the detector 18 move relative to each other and relative to the body part. The controller 44 can also control the manner in which information (including images 42 and data acquired during operation) is processed, displayed, stored, and manipulated. The different processing steps performed by the controller 44 include receiving one or more signals from one or more sensors, receiving user input, evaluating the received signals / inputs, image processing, determining reconstruction errors, outputting operating parameters including error indications, and adjusting one or more actuators of the x-ray system to control the operation of the x-ray system, which can be provided by a set of instructions stored in a non-transitory memory of the processor. Information can also be stored in one or more non-transitory memories of the controller 44 for later retrieval and use.

[0050] In addition, as described above, the radiation detector 18 receives radiation rays emitted by the radiation source 16. Specifically, during imaging using the X-ray system, a projection image of the imaged body part can be obtained at the detector 18. In some exemplary embodiments, data received by the radiation detector 18 (such as projection image data) can be transmitted from the radiation detector 18 to the controller 44 electronically and / or wirelessly. The controller 44 can then reconstruct one or more scanned images based on the projection image data, for example by implementing a reconstruction algorithm. The reconstructed image can be displayed to the user on the user interface 50 via the display screen 56.

[0051] The radiation source 16 together with the radiation detector 18 form part of the X-ray system 10, which provides X-ray images for the purpose of screening for abnormalities, diagnosis, dynamic imaging and image-guided biopsy. For example, the X-ray system 10 can be operated in a mammography mode to screen for abnormalities. During mammography, the patient's breast is positioned and compressed between the detector 18 and the compression paddle 40. Therefore, the volume of the X-ray system 10 between the compression paddle 40 and the detector 18 is the imaging volume. The radiation source 16 then emits radiation rays onto the compressed breast, and a projection image of the breast is formed on the detector 18. The projection image can then be reconstructed by the controller 44 and displayed on the interface 50. During mammography, the gantry 15 can be adjusted at different angles to obtain images of different orientations, such as head-tail (CC) images and medial-lateral oblique (MLO) images. In one example, the gantry 15 can rotate around the axis 58 while the compression paddle 40 and the detector 18 remain stationary. In other examples, gantry 15 , compression paddle 40 , and detector 18 may rotate about axis 58 as a single unit.

[0052] In addition, the X-ray system 10 can be operated in a tomosynthesis mode for performing digital breast tomosynthesis (DBT). During tomosynthesis, the X-ray system 10 can be operated to direct low-dose radiation to the imaging volume (between the compression paddle 40 and the detector 18) at various angles within the angular range of the X-ray system 10. Specifically, during tomosynthesis, similar to mammography, the breast is compressed between the compression paddle 40 and the detector 18. The radiation source 16 is then rotated from -θ to +θ, and multiple projection images of the compressed breast are obtained at various angles within the angular range. For example, if the angular range of the x-ray system is ±11 degrees, the detector can capture 22 projection images approximately every degree of sweep during the angular sweep of the gantry. The multiple projection images are then processed by the controller 44 to generate a plurality of DBT image slices. The processing may include applying one or more reconstruction algorithms to reconstruct a DBT volume rendering of the breast.

[0053] Furthermore, the X-ray system may be configured to perform a DBT-guided biopsy procedure.Thus, in some exemplary embodiments, the system 10 may further include a biopsy device including a biopsy needle for extracting a tissue sample for further analysis. Figure 1C An exemplary biopsy device is shown.

[0054] Go to Figure 1C , shows a method that can be used with a mammography system such as, Figure 1B Schematic diagram of a biopsy device 140 for use with a mammographic system 100 of the present invention. Figure 1B1. The biopsy device 140 is described with reference to the mammography system 100 in FIG. The biopsy device 140 includes a biopsy table 155 positioned above the detector 18 of the x-ray system 10. In one example, the biopsy table 155 can be configured to slide above the detector 18. During the setting of the biopsy device 140, the user can remove the compression paddle 40 of the x-ray system 10 and slide the biopsy table 155 above the detector 18. When the biopsy device 140 is positioned on the x-ray system 10, a suitable compression paddle (not shown) for the biopsy, such as a horizontal paddle or a vertical paddle, can be selected according to the type of biopsy, and the suitable compression paddle can be connected to the x-ray system 10.

[0055] A biopsy device interface 160 having a biopsy device display 162 may be coupled to the biopsy table 155 via a communication port 164. In one embodiment, the biopsy device interface 160 may be communicatively coupled to the x-ray system controller 44, as indicated by the double-ended arrow 154, so that a user may be able to adjust the position of the x-ray system, such as adjusting the gantry to a parked position, via the biopsy device interface 160. In other embodiments, the biopsy device interface 160 may be coupled to the biopsy device controller 150, which sends information to and receives information from the x-ray system controller 44 (as indicated by the double-ended arrow 152). In some other embodiments, adjustment and control of the biopsy device 140 may additionally or alternatively be performed by a biopsy device control module 159 of the x-ray system controller 44.

[0056] Biopsy device 140 includes a biopsy tool system 170 that can be directly coupled to biopsy table 155. Biopsy tool system 170 includes a robotic system that includes a trunk 172 to which a first arm 174 is attached. Biopsy tool system 170 may also include a second arm 176 coupled to first arm 174 at one end and to biopsy gun holder 180 at an opposite second end. Second arm 176 may pivot relative to first arm 174 to adjust the position of the biopsy gun holder. Figure 1C The illustration in shows a biopsy tool system 170 configured for biopsy in a vertical approach. The vertical approach involves inserting an interventional tool (e.g., a biopsy needle) into the breast in a direction perpendicular to the horizontal plane of the compression paddle. The interventional tool may alternatively be referred to as a tool. It should be understood that the interventional tool (or tools) may include, but are not limited to, any of a biopsy needle, a hook wire, and an ablation needle / probe. Therefore, during the setting of the biopsy device 140 in a vertical approach, the biopsy gun holder 180 is positioned so that the longitudinal axis of the biopsy gun holder along the length of the biopsy gun holder is parallel to the z-axis 141 and perpendicular to the horizontal surface 156 of the biopsy table 155.

[0057] The biopsy tool system 170 can be adjusted to perform a biopsy in a lateral approach (also referred to as a horizontal approach) in which the needle is inserted into the breast in a direction parallel to the compression paddle. During the placement of the biopsy tool in the lateral approach, the second arm 176 can be pivoted 90 degrees via the knob 177 so that the longitudinal axis of the biopsy gun holder is perpendicular to the z-axis 141 and parallel to the horizontal surface of the biopsy table 155.

[0058] The biopsy gun holder 180 can be used to mount the biopsy gun 184. In addition, the biopsy gun holder 180 can include a mechanical stop for adjusting the position of the biopsy needle 190. Specifically, during a biopsy, before inserting an interventional tool, the breast is positioned between a compression paddle (not shown) and the surface 156. In some examples, a breast pad can be positioned on the surface 156, the breast is positioned between the compression paddle and the pad and compressed by moving the compression paddle toward the surface 156. When the breast is positioned, a first set of target images is obtained by scanning the compressed breast with the X-ray system 10 at various angles within its angular range to identify the target for biopsy. The first set of target images can be a three-dimensional image (DBT image) or a two-dimensional full-field digital mammography image acquired and reconstructed by the X-ray system. The user can locate the area of ​​interest and identify the target location for biopsy by selecting the target location from the first set of DBT images. The target location can be identified by the x-coordinate, y-coordinate, and z-coordinate within the DBT volume between the compression paddle and the biopsy table surface 156 or the pad (if used). Based on the user-selected target position coordinates, biopsy device controller 150 may adjust the mechanical stop position of biopsy gun holder 180 so that when the needle is inserted into the compressed breast via biopsy gun 184, the needle stops moving when the needle tip reaches a desired position relative to the target position. Although this example illustrates adjusting the biopsy device via biopsy device controller 150, it should be understood that in some embodiments, x-ray system controller 44 may command control of biopsy device 140. In this way, during a biopsy in vertical access mode, the depth position of the biopsy needle may be adjusted using biopsy gun 184 and biopsy gun holder 180 by moving first arm 174 upward and / or downward relative to trunk 172 to adjust the z position and mechanical stop position.

[0059] In addition, the biopsy tool system 170 may include a platform 173 and a guide rail 177. The trunk 172 of the biopsy tool system 170 may be moved above the platform 173 parallel to the x-axis 143. The movement of the biopsy tool system 170 above the platform 173 is indicated by the double-ended arrow 147. The movement of the trunk along the platform 173 can be adjusted by the controller. Therefore, during a biopsy, the position of the biopsy gun 184 and the gun holder 180 can be adjusted in the direction of the x-axis so that the x-axis coordinate of the tool position is adjusted relative to the target position. In addition, the platform 173 can be moved in the direction of the y-axis 142 along the guide rail 177. The movement of the biopsy tool system 170 in the y-axis direction is indicated by the double-ended arrow 148. Therefore, during a biopsy, the position of the biopsy gun and the gun holder can be adjusted in the direction of the y-axis so that the y-axis coordinate of the tool position is adjusted relative to the target position. In addition, the biopsy tool 170 can be moved up and down, as indicated by the double-ended arrow 149. For example, arm 174 may be movable in the direction of Z-axis 141 as indicated by arrow 149 to adjust the position of biopsy gun holder 180 (and thus biopsy gun 184 and biopsy needle 190) along Z-axis 141. Movement of the biopsy tool in the x-direction, y-direction, and z-direction may be regulated by controller 150. It should be understood that embodiments in which adjustment of the biopsy tool in one or more of the x-direction, y-direction, and z-direction is manually performed in addition to or as an alternative to adjustment by the controller are also within the scope of the present disclosure.

[0060] Since manual adjustments can be made, when DBT is performed after adjusting the tool, a new tool tip position can be determined based on the error model and the leakage observed in the DBT volume, as discussed further below.

[0061] In summary, during a biopsy, before inserting needle 190, when a target position is selected from a first set of target images obtained by the x-ray system, a controller (which may be x-ray system controller 44 or biopsy device controller 150) may adjust the biopsy tool in the direction of the x-axis 147, in the direction of the y-axis 148, and adjust the mechanical stop position in the direction of the z-axis based on the target position coordinates so that when the needle is inserted, the needle tip is at a desired position in the breast tissue relative to the target position.

[0062] In this manner, the robotic system of biopsy tool system 170 may be utilized to adjust the needle position and biopsy tool position based on the target position calculated from the images.

[0063] Once the biopsy tool system 170 and the biopsy gun are in the target position, the user / radiologist can drive the needle through the biopsy gun 184 until it reaches a mechanical stop. Once fully inserted, the needle is in the target position (i.e., the position where the needle notch is in front of the lesion for puncture). An exemplary illustration of a biopsy needle that can be used to perform a biopsy using the biopsy device 140 is shown in FIG. Figure 1D Shown in.

[0064] Go to Figure 1D , a schematic diagram of an exemplary biopsy needle 190 is shown. The biopsy needle may include a needle tip region 192, an outer sleeve 198, an inner sleeve 196 positioned in the outer sleeve, and an opening (recess) 194 for receiving a portion of tissue from a biopsy lesion or target. The inner sleeve and the outer sleeve form a cutting device, wherein the outer sleeve 198 is configured to slide or rotate above the inner sleeve, and / or the inner sleeve is configured to slide or rotate within the outer sleeve. In one example, during a biopsy, when the needle 190 is in a pre-fired position, the end and the recess of the needle tip 192 are above the target, and when the needle 190 is in a post-fired position, the recess is in front of the target. When the pre-fired position of the needle is confirmed (i.e., when the needle is in a desired position relative to the target), the user can actuate (i.e., fire) the biopsy gun to deploy the biopsy needle. When the biopsy needle is deployed (i.e., when the biopsy needle is fired), the needle tip can pass through the target tissue, and then the recess and the inner sleeve pass through the target tissue. When the inner cannula is inserted through the target tissue, a portion of the target tissue may settle on the notch. Almost instantaneously, the outer cannula may move forward and incise the portion of the tissue that has settled on the notch. A second set of post-firing images may be obtained by the x-ray system with the needle 190 in the post-firing position. The incised tissue is then extracted from the needle by an auxiliary method (such as vacuum-assisted biopsy) and the needle is removed from the patient.

[0065] When the biopsy needle 190 is imaged in the DBT volume, the biopsy needle 190 appears to leak in the z direction due to the limited resolution of the tomosynthesis image in the z direction (i.e., the direction perpendicular to the biopsy table surface 156). In other words, an artifact image of the biopsy needle 190 may be visible in additional image slices. Thus, the end of the needle tip observed in the image may be different from the actual end of the needle tip 192. This leakage of the needle tip in the z direction may also depend on the needle tip length 193 and the needle diameter 195, in addition to other parameters (including target position and x-ray system parameters) as further discussed below.

[0066] In one embodiment, a controller (such as Figure 1BThe controller 44 in the image processing unit 40 may store an error model that can be used to calculate reconstruction errors in reconstructions of images (including biopsy needle images) from tomosynthesis acquisitions. The error model may be based on needle parameters, including needle length and needle diameter, a selected target position within the imaging volume, and x-ray system parameters. During a breast biopsy procedure performed with a vertical approach, due to the poor resolution of DBT images in the z direction, the biopsy needle appears in a greater number of image slices and therefore appears to leak in the z direction. Therefore, when viewing a DBT reconstructed image with a biopsy needle, it may be difficult to determine the actual needle tip position (and therefore indirectly determine the notch position that may be clinically significant), and it may be difficult to determine whether the needle is in the expected position relative to the target position coordinates. Some of the above problems can be solved by determining the expected reconstruction error for a given selected needle based on the error model. The expected reconstruction error may indicate the expected amount of leakage of the selected needle before the needle is inserted for biopsy. Based on the expected leakage, the user may be informed of the expected reconstruction error even before the biopsy procedure is started, and may be able to determine whether the expected reconstruction error is acceptable for a given biopsy procedure. The following relative to Figures 2 to 6 Details of the error model and determination of reconstruction error prior to needle insertion are described.

[0067] In addition, the controller may store instructions for determining an actual needle tip position of a selected biopsy needle based on the needle volume observed in a reconstructed image of the needle in one or more of the pre-fire position and the post-fire position and an expected reconstruction error. Additionally, based on the observed needle volume and the expected reconstruction error, the controller may assess whether the needle has bent during insertion into the pre-fire position and subsequently into the post-fire position. Additionally, when the needle is in one or more of the pre-fire position and the post-fire position (such as the notch position), other regions of interest along the needle may be determined based on the observed needle volume and the expected reconstruction error. Figure 6 and Fig. 9 Details of utilizing expected reconstruction errors during a DBT-guided biopsy procedure are further described.

[0068] In some exemplary embodiments, the controller may store an error model for the interventional tool, which can be used to calculate the reconstruction error of the interventional tool when reconstructing an image including an interventional tool image from a tomosynthesis acquisition. The error model for the interventional tool may be based on interventional tool parameters, which include interventional tool length and interventional tool diameter, a selected target position within an imaging volume, and x-ray system acquisition parameters. In an interventional procedure performed with a vertical approach, due to the poor resolution of DBT images in the z direction, the interventional tool may appear in a greater number of image slices and therefore appear to leak in the z direction. Therefore, when viewing a DBT reconstructed image with an interventional tool, it may be difficult to determine the actual tool position and whether the tool is in the desired position relative to the target position coordinates. Some of the above problems can be solved by determining the expected reconstruction error of a given selected interventional tool based on an error model. The expected reconstruction error may indicate the expected leakage amount of the interventional tool selected before the insertion of the interventional tool. Based on the expected leakage, the user may be notified of the expected reconstruction error even before starting the interventional procedure, and may be able to determine whether the expected reconstruction error is acceptable for a given interventional procedure.

[0069] In addition, the controller may store instructions for determining an actual tool position of a selected interventional tool based on a tool volume observed in a reconstructed image of the interventional tool in one or more of the pre-fired position and the post-fired position and an expected reconstruction error of the selected interventional tool. Additionally, based on the observed tool volume and the expected reconstruction error, the controller may assess whether the tool has been bent during insertion into the tissue. Additionally, other regions of interest along the tool may be determined based on the observed tool volume and the expected reconstruction error.

[0070] Next, Figure 2 A high-level flowchart is shown that illustrates a method for selecting a method for utilizing an x-ray imaging system such as Figure 1B x-ray system 10 in the embodiment of the present invention) and a biopsy device (such as, Figure 1C Method 200 of using a biopsy needle for DBT-guided biopsy performed by a biopsy device 140 in a biopsy apparatus. Method 200 may be performed by an image processing system such as Figure 1B The method 200 may be implemented by a controller 44 in the image processing system, an edge device connected to the image processing system, a cloud in communication with the image processing system, or any suitable combination thereof. Figure 1B and Figure 1C Although described with reference to systems and components of the present invention, it should be understood that method 200 can be implemented with other systems and components without departing from the scope of the present disclosure. In addition, it should be understood that method 200 can be used to select interventional tools, including but not limited to biopsy needles, hook wires, and ablation needles / probes, according to the interventional procedures (e.g., biopsy, hook wire positioning, cryoablation, etc.) performed using the x-ray system.

[0071] Method 200 begins at 202. At 202, method 200 includes determining whether the x-ray system is operating in a biopsy mode. The biopsy mode operation may be determined based on detecting a biopsy device coupled to the x-ray system. During a setup operation for a biopsy procedure, for example, a biopsy device may be positioned over a detector of the x-ray system by sliding a biopsy table such as biopsy table 155 over the detector. In addition, a biopsy device interface such as Figure 1C The interface 160 in the x-ray system can be coupled to the x-ray system. In one example, the biopsy device can be automatically detected when one or more of the biopsy device and the biopsy device interface are coupled to the x-ray system. In another example, a user can indicate via a user interface of the x-ray system that the biopsy device is coupled to the x-ray system and that the x-ray system is in a biopsy operating mode.

[0072] If the biopsy mode is confirmed, the answer at 202 is yes, and the method 200 proceeds to 204. At 204, the method 200 includes determining whether a biopsy needle is selected for a biopsy procedure. For example, a user may select a desired biopsy needle from a set of prescribed biopsy needles based on one or more of a patient parameter, a target tissue parameter, a biopsy device parameter, and an x-ray system parameter. The user may then indicate the selection of the desired biopsy needle and the type of the selected desired biopsy needle via a user interface (such as a biopsy device interface or an x-ray system interface). Although the above examples describe biopsy needle selection, it should be understood that interventional tools may be selected based on interventional procedures performed using an x-ray system. Interventional tools may include, but are not limited to, hook wires for hook wire positioning and ablation needles for cryoablation. Therefore, in some embodiments, at 202, the method 200 may include determining the type of interventional procedure (e.g., hook wire positioning, cryoablation, etc.), and at 204, the method 200 may include determining whether a corresponding interventional tool (e.g., hook wire, ablation needle, etc.) is selected for the interventional procedure.

[0073] In some embodiments, a user may install a desired biopsy needle into a biopsy gun such as Figure 1C 184 in the biopsy gun. In such cases, the presence of the biopsy needle can be determined based on sensing of the biopsy needle by one or more sensors coupled to one or more of the biopsy holder and the x-ray system. An exemplary sensor system may include a computer vision system. Other types of sensors for sensing the loading of the biopsy needle and the presence of the biopsy needle in the biopsy holder are also within the scope of the present disclosure.

[0074] If the selection of the biopsy needle is not confirmed, the answer at 204 is no, and the method 200 continues to monitor the biopsy needle selection. It should be understood that in some examples, upon confirmation of the biopsy mode, the method 200 may proceed to 205, and may confirm the needle selection and / or loading at a later step before commanding any needle movement.

[0075] If the desired biopsy needle is selected, the answer at 204 is yes, and method 200 proceeds to 205. At 205, method 200 includes determining whether a body part, such as a breast, is positioned for biopsy. Prior to a breast biopsy procedure, compression paddles are used to compress the breast to reduce movement during the biopsy. When the desired fixation is achieved, the user may indicate via the x-ray system user interface and / or the biopsy device interface that the breast is in a proper position for imaging. Thus, it may be determined whether the breast is in a proper position based on the user indication. In some examples, one or more sensors (e.g., visual sensors) coupled to the x-ray system and / or the biopsy device may be used to determine whether the breast is positioned for imaging.

[0076] If the breast is not positioned for imaging, the answer at 205 is no, and the method 200 proceeds to monitoring the positioning of the breast. If the breast is positioned for imaging, the answer at 205 is yes, and the method 200 proceeds to 206. At 206, the method 200 includes acquiring a first set of projection images at various angles within the angular range of the x-ray system. Specifically, before commanding the biopsy needle to reach the pre-fire position, the x-ray system may perform a first tomosynthesis scan using the x-ray system to generate a first set of projection images of the compressed breast at the detector. The first set of projection images may include a scout image and a plurality of projection images (obtained using an x-ray tube positioned at zero degrees to a midline axis perpendicular to the top surface of the detector) at various angles within the angular range of the x-ray system. For example, if the angular range of the x-ray system is 22 degrees, the x-ray system may acquire a first set of projection images using an x-ray tube at various angles ranging between -11 degrees from the midline and +11 degrees from the midline. During DBT-based image acquisition, at each angulation within the angular range of the x-ray system, a cone beam of low-dose x-ray radiation from an x-ray tube may pass through the compressed breast and be projected onto a detector to obtain a projection image.

[0077] When the first set of projection images is obtained, the method 200 proceeds to 208. At 208, the first set of projection images from the detector are reconstructed into slices of the breast volume, each slice having a certain amount of thickness (e.g., 1 mm) to obtain a first set of reconstructed images, and displayed on a user interface of the x-ray system. The first set of images are tomosynthesis reconstructed images, and can be displayed on the user interface in a sequential cycle at a desired rate, and the images can alternatively be viewed one by one based on user preferences. In this way, by moving the x-ray tube within the angular range, capturing multiple projection images of the breast at various angles within the angular range, and reconstructing the multiple projection images into multiple slices throughout the breast volume in the z direction, a first set of reconstructed images (before inserting a biopsy needle into the compressed breast) can be obtained.

[0078] Next, at 210, method 200 includes determining whether to select a biopsy target location for biopsy. The target location for biopsy may be within the region of interest and may be selected by a user via an X-ray system user interface and / or a biopsy device interface based on identifying an abnormality from a first set of reconstructed images. The abnormality may be an indication of breast cancer and may include one or more of lesions, microcalcifications, distortions of tissue structure, and any deviations from normal breast anatomy that may be indicative of breast cancer. For example, a user may select a target by highlighting the target location. The target location may be alternatively referred to herein as a target position. Although the above examples describe a biopsy target location, it should be understood that the target location may be selected for any image-guided interventional procedure, such as hook wire positioning, cryoablation, and the like.

[0079] If the biopsy target location has not been identified, the answer at 210 is no, and method 200 proceeds to 211. At 211, method 200 includes prompting the user to identify a target. Method 200 may then return to step 210 to determine whether a biopsy target has been selected. If the biopsy target location is identified, the answer at 210 is yes, and method 200 proceeds to 212. At 212, method 200 includes determining a first expected reconstruction error for a selected biopsy needle within an entire DBT reconstruction volume. The entire DBT volume may include each volume slice in a separate volume slice of a first set of reconstructed images. Specifically, the first expected reconstruction error may be determined based on an error model. The error model is based on selected needle parameters, selected biopsy target location, and x-ray system parameters. It may be noted that the error model may be implemented for any selected interventional tool, including but not limited to hook wire, ablation needle, biopsy needle, etc. Thus, the error model may be based on selected interventional tool parameters, a selected target location for a desired interventional procedure, and x-ray system parameters. With respect to Figure 3A and Figure 3BDetails of determining the first expected reconstruction error based on the error model are further described.

[0080] Now go to Figure 3A , which is a high-level flow chart illustrating a method 300 for determining an expected reconstruction error in image reconstruction of a needle during a DBT-guided biopsy. The method 300 may be implemented by an image processing system (such as the controller 44 in FIG. 1 ), an edge device connected to the image processing system, a cloud in communication with the image processing system, or any suitable combination thereof. Figure 1B , Figure 1C and Figure 1D The method 300 is described with reference to the systems and components of FIG. 3 , but it should be understood that the method 300 can be implemented with other systems and components without departing from the scope of the present disclosure. In an exemplary embodiment, the method 300 can be implemented by a biopsy holder controller that communicates with an image processing system.

[0081] As described above, during DBT imaging, the x-ray system rotates within the angular range of the x-ray system to acquire multiple projection images, which are then reconstructed into multiple 3D slices of the breast volume. Since the x-ray system is not fully rotated (360 degrees) during DBT, the DBT reconstructed images have poor resolution in the z direction, resulting in reconstruction errors that can cause the biopsy needle to be visible in a greater number of planar slices of the breast volume than the actual plane. In other words, the length of the needle in the reconstructed image can appear longer than the actual length of the needle. Therefore, when the needle is inserted into the breast, the reconstruction error can cause the needle tip to appear at a different position than the actual needle tip position. Therefore, the user cannot determine whether the needle tip is within a threshold error distance from the target position for biopsy. By determining the reconstruction error before inserting the needle, the user can be able to evaluate whether the expected reconstruction error is acceptable. Method 300 shows the determination of the expected reconstruction error even before the needle is inserted into the compressed breast. Method 300 can be started when the target biopsy position is selected from the first set of reconstructed images and the biopsy needle is selected, and before the needle is commanded to move to the pre-fire position. In addition, it should be understood that method 300 may be implemented to determine expected reconstruction errors of tools in image reconstruction of interventional tools (including but not limited to biopsy needles, hook wires, and ablation needles / probes) based on interventional procedures (e.g., biopsy, hook wire positioning, cryoablation, etc.) performed using an x-ray system.

[0082] Method 300 begins at 302. At 302, method 300 includes determining one or more of selected needle parameters, selected biopsy target location parameters, and acquisition system parameters. The needle parameters may include a selected needle orientation (e.g., vertical, horizontal, or tilted (and if the orientation is tilted, a desired tilt angle)), a selected needle body portion (e.g., Figure 1DThe diameter of the inner sleeve 196 in (such as, Figure 1D diameter 195) and a selected needle tip length (such as, Figure 1D The needle parameters may be specific to the selected needle. In one example, a user may indicate the type of needle selected via one or more of a biopsy device user interface and an x-ray system user interface, and the needle parameters may be determined by the controller based on the specifications of the selected needle stored in a non-transitory memory of the controller. It should be understood that it is also within the scope of the present disclosure to determine the needle parameters based on one or more sensors coupled to one or more of the biopsy device and the x-ray system.

[0083] When the needle is inserted into the compressed breast, the selected biopsy target position parameters may include an expected tip position along the z-direction. That is, the expected depth position of the needle tip along the z-direction perpendicular to the detector plane may be determined based on the selected biopsy target position. For example, during a vertical biopsy approach, when the desired needle movement is downward along the z-axis toward the detector plate, the pre-fire position of the needle may be slightly higher than the target position along the z-axis so that when fired, the needle tip passes through the target position to collect target tissue at the notch for analysis. Therefore, the expected tip position along the z-axis in the pre-fire position may be determined based on the target position selected from the first set of reconstructed images (and therefore the expected notch position relative to the target position is determined based on the expected tip position and the needle parameters). In some examples, the selected target position parameters may include the x-coordinate, y-coordinate, and z-coordinate of the target position.

[0084] The acquisition system parameters include the acquisition system geometry, which includes the rotational angular range of the x-ray acquisition system, one or more focal point parameters (position and size), and the source-to-image distance (i.e., the distance from the focal point (at which the x-rays are generated) to the detection surface of the detector). For example, the angular range of the x-ray system from the middle (zero degrees) in one direction may vary between ±11 degrees and ±60 degrees depending on the manufacturer. While the above example shows a range between 11 degrees and 60 degrees based on current manufacturing capabilities, it should be understood that x-ray systems with angular ranges below ±11 degrees and above ±60 degrees are also within the scope of the present disclosure.

[0085] Next, the method 300 proceeds to 304. At 304, the method 300 includes determining an expected reconstruction error (Re) based on an error model constructed according to an expected position of the needle tip in the DBT volume, an orientation of the needle, a diameter of the needle body, a length of the needle tip, and a rotation range of the acquisition system. Specifically, the reconstruction error increases as the needle is oriented more vertically. Furthermore, the reconstruction error increases as the needle diameter increases. Furthermore, the reconstruction error increases as the tip position in the DBT volume approaches the detector. Furthermore, the reconstruction error increases when the angular range of the acquisition system decreases.

[0086] In one example, the expected reconstruction error may be calculated based on an error model that depends on selected needle parameters, selected target location, and acquisition system parameters, such as Figure 3B Go to Figure 3B , a block diagram 350 of an error model 360 according to an exemplary embodiment is shown. The error model 360 uses selected needle parameters 364 (length, diameter, and orientation), needle tip position 366 along the z-axis (which is based on the target position selected from the first set of reconstructed images), and acquisition system parameters 368 (angular range) as input. The error model provides an expected reconstruction error Re as output.

[0087] In another example, a reconstruction error data set may be stored in a non-transitory memory of the controller, the reconstruction error data set comprising reconstruction error data for a given set of needle types (each type having a specific needle length and diameter) for a given x-ray system determined at various distances from the detector. In one example, the reconstruction error data set may be based on an error model as described above. In another example, the reconstruction error data set may be based on evaluating the reconstructed tip length observed in air at a specific distance along the z-axis for each needle model. The observed reconstructed tip length may be compared to the actual position of the needle tip in air to determine the reconstruction error for each needle model. In this way, a reconstruction data set may be constructed and stored. During a DBT-guided biopsy, before commanding any movement of the needle through compressed breast tissue, a first expected reconstruction error may be determined from the reconstruction error data set based on the selected needle type and the selected target location. Figure 4 An exemplary set of tables with reconstruction error data that may be stored in a memory of an image processor is described.

[0088] Go to Figure 4 , shows a set of exemplary reconstruction error data tables. Specifically, a first data table 400 and a second data table 450 are shown. The first data table 400 and the second data table 450 include data based on an error model (such as the above relative to Figure 3A and Figure 3B The reconstructed error data of the biopsy needle determined by the error model in question.

[0089] In some examples, reconstruction error data for a biopsy needle may be determined by obtaining tomosynthesis projection images of various biopsy needle models in air at multiple distances from the detector in a DBT volume between a compression paddle and a detector. In addition, for a given needle model, during generation of a reconstruction error data table, the vertical axis of a given needle may be positioned at zero degrees from a centerline, which is a vertical axis perpendicular to the detector and the compression paddle. Thus, the given needle is positioned in a vertical approach position perpendicular to the detector and the compression paddle. Tomosynthesis projection images of the corresponding needle in air may be obtained at various angles within the angular range of the x-ray system. The tomosynthesis projection images of the needle in air may then be reconstructed. The observed needle tip length and the observed needle tip end in the reconstructed volume between the detector and the compression paddle may be determined based on the reconstructed image of the needle in air. The observed needle tip may be compared with the actual physical needle tip length and needle tip end position along the z-axis to determine reconstruction error data for a given needle model at multiple distances from the detector. In one example, the actual needle tip end position may be based on a target position input by a user. In this way, reconstruction error data sets for various needle models can be determined based on tomosynthesis reconstructed images of the various needle models in air. Although the above example of determining reconstruction error data is described with respect to a biopsy needle, it should be understood that reconstruction error data for any interventional tool can be determined based on tomosynthesis projection images of corresponding interventional tool models generated in air as described above.

[0090] The first data table 400 shows reconstruction error data for the end of the needle tip positioned 54 mm above the top surface of the detector. Table 400 shows the reconstruction error for different needle diameter (D) and needle length (L) combinations at 54 mm above the detector. Similarly, the second data table 450 shows the reconstruction error for different needle diameter (D) and needle length (L) combinations at 20 mm above the detector. As shown in Tables 400 and 450, the reconstruction error increases with increasing needle diameter, decreasing needle tip length, and decreasing distance from the detector. In addition, as shown in the gray shaded box, for a given needle diameter, the reconstruction error is minimum (greater than zero) when the needle tip length is approximately twice the needle diameter. In other words, the reconstruction error is minimum (greater than zero) when the diameter is approximately half the needle tip length. In addition, for a given needle tip length and a given needle tip diameter, the reconstruction error increases as the needle tip end approaches the detector plate.

[0091] Although Figure 4 Two exemplary reconstruction error data sets are shown at two different distances from the detector, but it will be understood that the processor may store multiple data sets for various combinations of needle lengths and diameters at multiple distances above the detector and also at multiple positions (in the xy plane) at each of the multiple distances above the detector (positions along the z-axis).

[0092] During a DBT-guided biopsy, when selecting a needle and a target location and before inserting the needle into compressed tissue, a first expected reconstruction error for the selected needle may be determined based on an error model or a reconstruction error dataset, or any combination thereof. In examples where a reconstruction error dataset is not available for the selected needle model and location in the DBT volume, the error model may be used to calculate the first expected reconstruction error, and then, if the determined error is greater than a threshold limit, the reconstruction dataset may be used to identify one or more candidate needle models that may have a smaller reconstruction error within acceptable limits, as discussed further below.

[0093] In some examples, an expected tool reconstruction error for a selected interventional tool may be determined based on an error model of the selected interventional tool, a tool reconstruction error dataset, or any combination thereof. Additionally, if the determined tool reconstruction error is greater than a threshold limit, the reconstruction error dataset may be used to identify one or more candidate tool models having a smaller tool reconstruction error within acceptable limits.

[0094] After determining the expected reconstruction error Re, the method 300 proceeds to 306. At 306, the method 300 includes determining whether the first expected reconstruction error is within a threshold error. The threshold error may be based on one or more of the size of the target (i.e., the size of the target lesion), the needle tip length, the needle notch position and depth, and the target position. For example, the error tolerance of a larger lesion may be larger, so the threshold error of a larger lesion may be larger. The threshold error may provide an indication of whether the selected needle can penetrate the target tissue position and excise the target tissue when fired. In some examples, the threshold error may also be set by the user. In addition, the threshold may be based on user preferences. For example, the user may prefer to rely on what they see in the DBT volume, and therefore use a tool that minimizes the error as much as possible. Alternatively, the user may choose to use any needle based on an indication of the expected error (and actual needle tip position) in the DBT volume from the error model.

[0095] Therefore, if the expected reconstruction error is not less than the threshold, the answer at 306 is no, and the method 300 proceeds to 307. At 307, the method 300 includes identifying one or more candidate needle models from the interventional tool database, the one or more candidate needle models having a corresponding Re that is less than the modeled Re of the given system (i.e., the first expected reconstruction error calculated based on the error model at 304) and the target parameter and less than the threshold error limit. In one example, the needle model with the corresponding Re can be determined based on a set of data tables. For example, a corresponding data table for a selected target position along the z-axis (needle tip depth along the z-axis) can be identified. Alternatively, if a data table for the selected target position is not available, a data table for a target position closest to the selected target position can be selected. When identifying the data table, one or more candidate needle models having a reconstruction error less than the threshold error limit can be identified from the table. When the one or more candidate needle models are identified, the method 300 proceeds to 310.

[0096] Returning to 306, if the first expected reconstruction error is less than the threshold, the answer at 306 is yes, and the method 300 proceeds to 310. At 310, the method 300 includes updating the reconstruction error data table for the selected target location using the first expected reconstruction error Re of the selected needle and the current acquisition system. Then, the method 300 returns to Figure 2 Step 212 of the method.

[0097] Return to Figure 2 , after determining the expected reconstruction error Re, method 200 proceeds to 214. At 214, method 200 includes providing first expected reconstruction error information to the user before moving the needle to the pre-fire position. Providing the first expected reconstruction error includes providing an estimated position difference between the physical tip position and the reconstructed tip position at 216. The estimated position difference may include an expected leakage distance between the actual physical tip position and the reconstructed tip position along the z-axis. In addition, providing the first expected reconstruction error includes providing one or more candidate needle models (identified at step 307) within a threshold error to the user at 218. The estimated position difference and one or more candidate needle models may be provided to the user via one or more of a user interface of the x-ray system and a user interface of the biopsy device. In one example, in addition to indicating the leakage distance in a standard metric (e.g., in millimeters), the position difference may also be presented to the user graphically.

[0098] An exemplary graphical representation of needle tip leakage distance is shown in Figure 5 Go to Figure 5 , which shows a schematic diagram of an exemplary leakage of the needle tip in the z direction in the reconstructed image due to reconstruction error. Specifically, Figure 5 An x-ray system (such as, Figure 1B 500 of the x-ray system 100 in FIG. 504. A biopsy needle 508 is included in a DBT volume 522 between a compression paddle 504 and a detector 504. The biopsy needle 508 is oriented in a vertical approach mode, wherein a vertical needle axis along the length of the needle is perpendicular to the compression paddle 502 and the detector 504. Additionally, the needle 508 is shown positioned slightly offset from and parallel to the vertical axis 505 (z-axis). It should be understood that in the vertical approach orientation, the needle 508 is oriented perpendicular to the compression paddle 502 and the detector 504, while the needle can be positioned at any location within the DBT volume 522, and based on a target location selected by a user, the needle tip end location can be indicated by a 3D coordinate within the DBT volume.

[0099] The angular range of the x-ray system is shown by arrow 506 and two angular positions of the x-ray tube 520, -θ and +θ. A first cone beam of x-rays from the x-ray tube 520 at the +θ position is shown by dashed line 540, and a second cone beam from the x-ray tube 520 at the -θ position is shown by dashed line 545. In this exemplary illustration, the needle 508 is shown positioned in air within the DBT volume 522. The needle 508 may have an actual needle tip length 510 and a needle tip end 515. The needle tip portion of the needle 508 is shown by vertical hatching. However, when the needle is imaged within the DBT volume 522 by moving the x-ray tube 520 at multiple angles within the angular range -θ to +θ and reconstructing a projection image of the x-rays projected onto the detector 504, the needle tip appears in the larger DBT volume 522 along the z-axis (505) of the reconstructed image. Thus, the observed needle tip length 512 is greater than the actual needle tip length 510, and due to the reduced resolution of DBT imaging in the z-direction, the needle tip is considered to leak in the perpendicular direction along the z-axis. Therefore, the reconstruction error of the biopsy needle (indicated by the cross-hatching enclosed in area 535) may include a leakage distance of the needle tip along the z-axis. In this way, the observed needle tip end 525 may deviate from the actual needle tip end 515, and the leakage distance along the z-axis may be the position difference between the actual needle tip end position 515 and the observed needle tip end position 525. In some examples, the leakage distance may be calculated as the difference between the observed needle tip length 512 and the actual needle tip length 510.

[0100] Figure 6 shows that when using Figure 5Schematic diagram of exemplary leakage at the needle tip in the z direction in the reconstructed image due to reconstruction error when using a smaller diameter needle 608 than the needle 508 in FIG. As shown, as the needle diameter decreases, the leakage distance decreases. Therefore, when a smaller diameter needle is used, the difference between the observed needle tip length 612 in the reconstructed image and the actual needle tip length 610 is smaller. In addition, the actual needle tip end 615 is almost coincident with the observed needle tip end 625.

[0101] Thus, depending on the type of needle, the needle tip may appear in additional image slices in the reconstructed image due to reconstruction error. Thus, the reconstruction error may include a leakage distance between the actual needle tip and the observed needle tip. By modeling the reconstruction error based on selected needle parameters, a selected target location, and acquisition parameters, the reconstruction error may be estimated prior to inserting the needle into the compressed breast. The user may determine that the currently selected needle may not be suitable for biopsy based on the expected reconstruction error, and may select a needle with a smaller reconstruction error than the currently selected needle (e.g., based on one or more candidate needle models having a reconstruction error less than a threshold limit presented to the user).

[0102] Fig. 7A A high-level method 700 is shown for assessing actual needle position as the needle is inserted into a compressed breast during a DBT-guided biopsy. Specifically, assessing actual needle position may include inferring actual needle tip position, and determining whether the needle has bent during insertion. Additionally, other parameters may be determined, including reconstruction error regions in the DBT image volume, and other points of interest along the needle, such as notch locations. The method 700 may be performed by an image processing system ( Figure 1B The method may be implemented by a controller 44 in the image processing system, an edge device connected to the image processing system, a cloud communicating with the image processing system, or any suitable combination thereof. Figure 1B , Figure 1C and Figure 1D Method 700 is described with reference to the system and components of FIG. 700 , but it should be understood that method 700 may be implemented with other systems and components without departing from the scope of the present disclosure. Although method 700 and method 800 (in FIG. Figure 8 ) in detail evaluates the actual biopsy needle position during a DBT-guided biopsy (particularly when the needle is in a pre-fire position), but it should be understood that methods 700 and 800 are applicable to evaluating any position (pre-fire position, post-fire position, etc.) of any interventional tool (e.g., hook wire, ablation needle, biopsy needle, etc.) inserted into tissue. Figure 1A A high-level schematic diagram illustrating assessment of interventional tool location within tissue is described.

[0103] Method 700 begins at 702. At 702, method 700 includes determining whether the biopsy needle selection is confirmed. Confirmation of the biopsy needle selection may be based on user input. For example, the user may select a desired biopsy needle based on the first reconstruction error and confirm the selection of the biopsy needle via a user interface (such as a user interface of the biopsy device, a user interface of the x-ray system, or a combination thereof). If the needle selection is not confirmed, the answer at 702 is no, and method 700 proceeds to 703. At 703, method 700 includes prompting the user to confirm the biopsy needle selection via the user interface. For example, a prompt may be displayed to the user via the user interface as described above in Figure 2 , Figure 3A and Figure 3B The expected reconstruction error of the current needle determined based on the error model described in , and an indication requesting the user to confirm whether the current needle is to be used for a DBT-guided biopsy procedure may be provided to the user via the user interface. The method 700 may then return to 702.

[0104] If needle selection is confirmed, the answer at 702 is yes, and method 700 proceeds to 704. At 704, method 700 includes providing the biopsy target location coordinates to the biopsy tool holder control system. The biopsy target location coordinates may be determined based on a user selecting a target location on the DBT reconstructed volume of the compressed breast prior to inserting the needle into the breast. For example, the user may select the target location on the DBT reconstructed volume of the compressed breast via a user interface by viewing (e.g., in Figure 2 The controller may select a target location for biopsy by selecting the DBT volume represented in the first set of reconstructed images (obtained at step 208) and selecting a target portion of the breast having an abnormality (e.g., by clicking a specific point within the abnormality or an area containing the abnormality). When the user selects the biopsy target location, the controller may extract the target coordinates within the DBT volume, including the x coordinate (x 目标 ), y coordinate (Y 目标 ) and the z coordinate (Z 目标 ). An exemplary determination of target biopsy coordinates is Figure 7C Shown in.

[0105] Now go to Figure 7C , shows a set of reconstructed images 770 representing an exemplary DBT volume. The set of reconstructed images 770 can be obtained by scanning a breast within its angular range (-θ to +θ) using an x-ray system. The set of reconstructed images includes multiple images 781, 782, 783, 784 reconstructed at various planes perpendicular to the detector along the z-axis. A user can view each of the multiple images and select a plane that includes a target portion for biopsy. When a user selects an image, a corresponding plane is selected, and the corresponding plane provides a z coordinate for the target position. In addition, the pixel position of the target can provide an x ​​coordinate and a y coordinate. Therefore, in this example, a user can select a target position 772 from the set of reconstructed images 770. A controller such as Figure 1B The controller 44 in FIG. 40 may determine Z based on the selected plane distance 774 from the reference plane 780. 目标 , based on the selected pixels of the target position 772 with respect to the Y 参考 and X 参考 The X coordinate 778 and the Y coordinate 776 are used to determine the X 目标 and Y 目标 For example, the reference plane may be the top surface plane of the detector. Therefore, based on the user's selection of the target position 772, the plane including X 目标 , Y 目标 and Z 目标 The target coordinates.

[0106] After the target position coordinates are determined, the target coordinates can be transmitted to the biopsy tool control system. The biopsy tool control system can command one or more actuators of the biopsy tool to position the needle guide of the biopsy gun holder at the mechanical stop position so that when the needle is inserted, the notch of the needle is in front of the lesion to be punctured. That is, relative to the target coordinates (X) determined from the reconstructed image of the DBT volume 目标 , Y 目标 and Z 目标 ) Positioning the needle. The position in which the needle is retracted into the gun and the tip of the needle is therefore positioned above the lesion for excision may be referred to as the pre-fire position. When the biopsy tool control system is used to adjust the biopsy needle holder to the desired position so that the needle guide is in the mechanical stop position, the user may insert the biopsy needle into the compressed breast until the mechanical stop prevents the needle from moving further. That is, the biopsy needle may be inserted into the compressed breast until the needle reaches the pre-fire position, and then the biopsy gun is fired and the needle reaches the post-fire position. In some embodiments, the insertion of the needle into the pre-fire position may be automatic. For example, when the user instructs the needle to move to the pre-fire position, the biopsy holder may automatically move the biopsy needle to the pre-fire position. Although this example illustrates the use of a biopsy tool control system to adjust the needle position, it should be understood that the movement of tools including the biopsy gun and the biopsy needle may be commanded by the x-ray system controller and is within the scope of the present disclosure.

[0107] Returning to 704, as described above, method 700 includes sending the target position coordinates determined based on the target position selection in the reconstructed image to the biopsy needle holder control system. As described above, the biopsy needle holder control system can then position the biopsy needle holder based on the target position coordinates and adjust the mechanical stop position on the needle guide of the biopsy gun so that when the needle is inserted into the compressed breast, the movement of the needle is stopped automatically by the biopsy tool control system, the x-ray system controller, or by the user (via the mechanical stop) when the needle tip is at the target position coordinates. After the needle is inserted, the biopsy tool control system can send the needle position (including the needle tip position) determined by the biopsy tool control system to the x-ray system controller. For example, the biopsy needle holder control system can calculate the needle tip position based on sensor data from a robotic system coupled to the biopsy needle holder control system, as further described below. The needle position returned by the biopsy tool control system (and therefore the robotic system) is the needle position in real physical space (i.e., the physical volume between the compression paddle and the detector) and can be referred to as a theoretical needle position.

[0108] Next, method 700 proceeds to 706. At 706, method 700 includes confirming whether the needle is in the pre-fire position. The pre-fire position can be confirmed based on user input via a user interface indicating that the needle is in the pre-fire position. In addition or alternatively, the needle pre-fire position can be confirmed based on the needle position returned from the biopsy tool control system. If the needle is not in the pre-fire position, the answer at 706 is no, and the method proceeds to 707. At 707, method 700 includes monitoring user input and / or data from the biopsy needle. Then, method 700 can return to determine whether the needle is in the pre-fire position. If the needle is in the pre-fire position, the answer at 706 is yes, and method 700 proceeds to 708.

[0109] At 708, method 700 includes acquiring a plurality of pre-fire DBT scans with the needle in the pre-fire position. The plurality of pre-fire scans may include a scout scan acquired with an x-ray source at zero degrees to a vertical axis of the x-ray system, the vertical axis being perpendicular to a top surface of the detector. The plurality of scans may also include a plurality of stereo scans acquired with the x-ray source at various angles (-θ to +θ) to the vertical axis within an angular range. For example, upon confirming that the needle is in the pre-fire position, the x-ray source may be rotated within the angular range of the x-ray system, and the plurality of pre-fire scans with the needle in the pre-fire position may be obtained.

[0110] Next, at 710, method 700 includes reconstructing a plurality of DBT target images based on the acquired pre-fire scan. Specifically, a plurality of projection image data sets obtained from detector exposure during a pre-fire scan in which the x-ray tube moves within an angular range can be reconstructed into a plurality of thin (e.g., one millimeter thick) slice images. The plurality of thin slice images from the pre-fire scan (also referred to herein as pre-fire DBT reconstructed images or simply pre-fire DBT images) can together provide a tomosynthesis reconstruction volume of a compressed breast with the needle in a pre-fire position. In some examples, in addition, a two-dimensional positioning image can be reconstructed based on the pre-fire scan.

[0111] Continuing to 712, method 700 includes determining inserted needle parameters based on the pre-fire DBT image. The inserted needle parameters based on the pre-fire DBT image may include a second reconstruction error of the biopsy needle in the pre-fire position, an amount of needle bending due to needle movement through breast tissue to the pre-fire position, and an actual needle tip position. In addition, the inserted needle parameters may include target position coordinates determined based on the DBT image acquired before the needle was adjusted to the pre-fire position, and a theoretical needle position in real physical space determined by the biopsy tool control system (via the robotic system). The following will be discussed with respect to Figure 8 Describes the details of determining the inserted needle parameters.

[0112] Go to Figure 8 , shows a high-level flow chart 800 for determining inserted needle parameters from pre-fire DBT images. The method 800 may be performed by an image processing system ( Figure 1B The method may be implemented by a controller 44 in the image processing system, an edge device connected to the image processing system, a cloud communicating with the image processing system, or any suitable combination thereof. Figure 1B , Figure 1C and Figure 1D The method 800 is described with reference to the systems and components of FIG. 8 , but it should be understood that the method 800 may be implemented with other systems and components without departing from the scope of the present disclosure.

[0113] The method 800 starts at 802. At 802, the method 800 includes determining a needle tip leakage volume observed in a DBT volume based on a visible volume of the needle tip observed in a pre-fire DBT reconstructed image. Determining the observed needle tip leakage volume may include determining a needle area observed in each of the plurality of DBT image slices, and determining the leakage volume based on the needle area observed in each of the plurality of DBT image slices.

[0114] Next, method 800 proceeds to 804. At 804, method 800 includes determining an expected needle tip leakage volume based on an expected reconstruction error. The expected reconstruction error may be determined as described with respect to FIG. 3 and may be based on an error model. That is, the expected reconstruction error may be modeled based on target position coordinates, needle parameters, and acquisition system parameters. In some embodiments, the expected reconstruction error may be modeled based on the needle position, needle parameters, and acquisition parameters returned by the robotic system. Furthermore, the expected leakage volume may be calculated based on a minimum amount of needle bending during insertion into breast tissue and based on the needle tip reaching its expected target position during insertion.

[0115] Next, after determining the observed needle tip leakage volume and the expected needle tip leakage volume, method 800 proceeds to 806. At 806, method 800 includes comparing the observed leakage volume with the expected leakage volume. In one example, a visual image processing descriptor can be used to compare the observed leakage volume with the expected leakage volume. For example, the visual image processing descriptor may include one or more of a local feature descriptor (e.g., shape, position, scale, orientation, and local image structure such as gradient, intensity, etc.) and a global feature descriptor. In general, comparing the observed leakage volume with the expected leakage volume includes comparing the needle tip shape observed from the pre-firing DBT reconstructed image with the expected needle tip shape based on an error model, and comparing the needle tip position observed from the pre-firing DBT image with the expected needle tip position based on the error model, and also includes comparing the observed needle tip volume with the expected needle tip leakage volume.

[0116] Next, at 808, method 800 includes determining whether the observed leak matches the expected leak. This includes determining whether the observed leak volume is within a threshold leak volume deviation from the expected leak volume, and whether the observed needle tip position is within a threshold distance from the expected needle tip position, and also includes determining whether the observed needle tip shape matches the expected needle tip shape.

[0117] If the observed leakage matches the expected leakage, the method 800 proceeds to 810. At 810, the method 800 includes determining the inserted needle parameters. Specifically, the inserted needle parameters may be determined based on an expected needle tip volume and shape, which is modeled using an expected leakage based on an error model. That is, when the expected leakage matches the observed leakage, the actual needle is in the expected pre-fire position, and the expected leakage (including the expected needle tip volume and shape) may be used to determine the actual needle parameters, including the actual needle tip position. Therefore, when the expected leakage matches the actual leakage, determining the inserted needle parameters may include determining the actual needle position based on an expected reconstruction error in the DBT volume at 812. Therefore, based on the expected reconstruction error of the needle tip in the pre-fire position (wherein the expected reconstruction error is determined based on the error model) and the needle leakage observed in the pre-fire DBT reconstructed image, the actual needle tip position within the compressed breast volume (i.e., the position of the needle tip in the actual physical volume) may be determined.

[0118] Furthermore, in an exemplary embodiment, the biopsy needle holder control system can also calculate the needle tip position based on sensor data from a robotic system coupled to the biopsy needle holder control system. Specifically, in a direct model calculation method, the Cartesian tip position can be determined in real time based on sensor feedback from the robotic system regarding the robot axis position, the geometric model of the robotic system, the biopsy device, the biopsy needle, and calibration parameters. That is, based on the direct model calculation method,

[0119] (X 尖端 ,Y 尖端 ,Z 尖端 )=M(X 机器人 ,Y 机器人 ,Z 机器人 , biopsy device and needle, calibration parameters)

[0120] Where X 尖端 , Y 尖端 , Z 尖端 is the Cartesian coordinate of the tip position, and M(X 机器人 ,Y 机器人 ,Z 机器人 , biopsy device and needle, calibration parameters) are the robot's position based on the robot axis X 机器人 , Y 机器人 , Z 机器人 , direct geometric model of biopsy device and needle dimensions and calibration parameters.

[0121] Therefore, the Cartesian tip position (X 尖端 ,Y 尖端 ,Z 尖端) is determined based on feedback from the robotic system and may therefore be referred to herein as the robotic returned tip position.

[0122] In addition, the robot axis (X 机器人 ,Y 机器人 ,Z 机器人 ) position can be determined based on the reciprocal geometry model as follows:

[0123] (X 机器人 ,Y 机器人 ,Z 机器人 )=M 倒数 (X 目标 ,Y 目标 ,Z 目标 , biopsy device and needle, calibration parameters)

[0124] Where X 目标 , Y 目标 , Z 目标 is the Cartesian coordinate of the target position selected from the reconstructed image, and M 倒数 (X 目标 ,Y 目标 ,Z 目标 , biopsy device and needle, calibration parameters) is the reciprocal geometric model of the robot based on the target position in the reconstructed image, the biopsy device and needle dimensions, and the calibration parameters.

[0125] In this embodiment, the tip position returned by the robot may be used to adjust the actual needle position information determined based on the expected reconstruction error in the DBT volume and the needle volume observed in the reconstructed image.

[0126] In addition, in this embodiment, a first position of the needle tip determined based on a target tip position selected from a reconstructed image, a second position of the needle tip determined based on a tip position returned by the robot, and a third position of the needle tip determined based on a pre-fire reconstruction image taking into account a second reconstruction error and the needle volume observed in the pre-fire reconstruction image can be used to detect one or more errors, including needle bending amount, robot sensor error, reconstruction algorithm error, calibration error, etc.

[0127] Thus, in one exemplary embodiment, the expected needle volume based on the reconstructed error of a selected needle in a pre-fire position (based on an error model determined based on needle parameters, target position parameters, and acquisition system parameters), the needle volume observed in the reconstructed image, and the tip position returned by the robot can be used to determine the inserted needle parameters, including the actual tip position, the amount of bend, the distance between the actual tip position and the expected tip position, and points of interest along the needle.

[0128] Returning to 810, in addition to determining the actual tip position at 812, determining the inserted needle parameters may include determining other needle features relative to the target position, such as the notch position in the DBT volume, based on the actual needle tip position and known needle features of the needle (e.g., diameter, length, etc.) at 813. Although the above examples show needle features, it should be understood that when using different interventional tools, the features of the interventional tools may be determined. For example, tool parameters that may be taken into account may include the portion of the tool that reaches the target lesion. For example, if a hook wire is used, the position of the hook portion of the hook wire may be determined. In addition, determining the inserted needle parameters may include indicating at 814 (based on the expected leak matching the observed leak) that the needle has reached the desired (pre-fire) position without bending. Alternatively, if one or more of the difference volumes between the observed leak and the expected leak are within a threshold volume, the position difference between the observed tip position and the expected tip position is within a threshold distance, and the shape difference is within a threshold limit, then the degree of similarity between the observed leak and the expected leak may be high, and therefore, it may be indicated that the needle has reached the pre-fire position with the bending amount within the threshold amount.

[0129] Additionally, at 816, a score indicating the degree of similarity between the observed leak and the expected leak may be provided. Additionally, when the observed leak does not match the expected leak (or is within a threshold volume deviation), determining the inserted needle parameters may include determining, at 817, a distance between the actual needle tip position and the expected needle tip position. If the observed leak matches the expected leak (i.e., the expected leak volume is equal to the observed leak volume, the observed needle tip position is the same as the expected needle tip position, and the expected leak shape is the same as the observed leak shape), then the actual needle tip position and the expected needle tip position coincide, and therefore the distance between the actual needle tip position and the expected needle tip position is zero. After determining the inserted needle parameters, method 800 returns to step 716 in method 700.

[0130] Returning to 808, if the observed leak does not match the expected leak (shape, location or volume), the answer at 808 is no and method 800 proceeds to 818. An exemplary illustration of a needle tip in a vertical approach where the observed leak does not match the expected leak is shown in FIG. Fig. 9 Shown in.

[0131] Continuing to 818, method 800 includes adjusting the expected reconstructed shape modeled based on the error model to match the observed needle tip shape. In some cases, when the biopsy needle is inserted into the breast, the needle trajectory may not follow the expected linear path. This may occur, for example, due to one or more of the needle tip applying force to the compressed breast asymmetrically, the needle insertion speed, and breast deformation. For example, the beveled needle tip may follow a circular arc trajectory that may be based on needle and tissue parameters. Due to needle bending, the observed needle tip shape may be different from the expected needle tip shape, and therefore, the expected needle tip shape (which is modeled based on the needle following a linear path) may not be used to obtain needle tip position information. Therefore, when the observed needle tip leakage does not match the expected needle tip leakage, a bending function may be applied to the error model. The bending function may adjust the expected needle tip shape so that the expected needle tip shape matches the observed needle tip shape. In this way, the error model may be adjusted to compensate for needle bending. Therefore, the compensated expected needle tip leakage that matches the observed leakage can now be used to infer the actual needle tip position. Next, method 800 proceeds to 820 .

[0132] At 820, method 800 includes determining pre-firing parameters using an error model that compensates for bend. Thus, determining pre-firing parameters includes determining an actual needle tip position based on an expected needle leakage compensated to match an observed needle leakage at 822. Additionally, in an exemplary embodiment, as described above with respect to 812, the actual tip position returned by the robot can be determined in real time and used to calculate one or more inserted needle parameters and errors. The details of the tip position returned by the robot are described with respect to 812 and will not be repeated for the sake of brevity.

[0133] In addition, at 824, with the needle in a pre-fire position relative to the target position in the DBT volume, other needle features such as the notch position may be determined based on the actual needle tip position, bending parameters such as the amount of bending and the needle trajectory, and known needle parameters such as the needle diameter, the needle tip length, and the position of the notch from the needle tip. In addition, determining the inserted needle parameters may include inferring at 826 that the needle did not reach the expected target coordinates due to bending (based on the observed leakage not matching the expected leakage (as determined at 808)). Determining the inserted needle parameters may also include determining at 828 a score indicating a degree of similarity between the observed leakage and the expected leakage. The degree of similarity may be based on one or more of: a difference between the observed needle tip volume and the expected needle tip volume, a position difference between the observed needle tip position and the expected needle tip position, and a shape difference between the observed needle tip shape and the expected needle tip shape in the reconstructed volume. Additionally, determining the inserted needle parameters may include determining a distance between the actual needle tip location (determined at 822) and the expected needle tip location (determined based on the needle reaching the target coordinates) at 830. The distance may be calculated as a distance in three-dimensional space (DBT volume).

[0134] Furthermore, during some procedures, the target lesion may move as the needle is inserted, even when the breast is compressed. Thus, in some embodiments, the user may reselect the target position with the needle in the pre-fire position, and the expected leakage in the DBT volume may be determined based on the newly selected target position (step 804) and subsequent determination of the pre-fire parameters as described above.

[0135] After determining the inserted needle parameters, method 800 may return to Fig. 7A Step 716 in .

[0136] Returning to 716, method 700 includes providing second reconstruction error information and the inserted needle parameters to the user. Providing the second reconstruction error information includes indicating a reconstruction error region of the imaged needle tip in the DBT volume at 718. The reconstruction error region may include one or more of a region between an observed needle tip shape and an expected needle tip shape, and a volume between an observed needle tip volume and an expected needle tip volume. In addition, the inserted needle parameters may be indicated to the user, the indication including: indicating an actual needle tip position at 720; indicating an amount of bend in the needle and indicating a distance between the actual needle tip position and the expected needle tip position at 722; and indicating a point of interest along the needle (e.g., a notch location) at 724. In addition, as described above, when different interventional tools are used, corresponding interventional tool parameters may be determined and displayed to the user.

[0137] In an exemplary embodiment, the second reconstruction error and the inserted parameters may be displayed as an overlay on the reconstructed image, or indicated separately, or a combination of the above may be provided. The type of display may be user-selectable. For example, the needle tip position may be indicated on a pre-fire DBT reconstructed image (such as, the pre-fire image from step 710) via highlighting or a graphical outline, while other inserted needle parameters, such as the amount of bend, similarity score, actual and expected needle tip distances, may be indicated separately. In addition, based on user selection, the separately indicated parameters may be displayed as an overlay on the pre-fire image. In addition, based on user selection, the reconstruction error area may be displayed as an overlay on the pre-fire image.

[0138] In another exemplary embodiment, a graphical representation of the needle tip may be provided separate from the reconstructed image.

[0139] In yet another exemplary embodiment, the second reconstruction error and one or more pre-fire parameters may be indicated via a schematic illustration of each of the DBT reconstructed image slices and displayed separately from or in combination with the DBT reconstructed image slices.

[0140] In this way, the second reconstruction error determined as described above and the inserted needle parameters can be displayed to the user via the user interface, including parameters of the actual needle tip position relative to the target position, other needle characteristics regarding the target position, the degree of similarity, the amount of curvature, and the distance between the actual needle tip position and the expected needle tip position. In addition, based on the second reconstruction error and the inserted needle parameters, the user can determine whether to continue with the current approach or whether a different approach (e.g., a horizontal approach) can be used for biopsy.

[0141] After providing the second reconstruction error and the inserted needle parameters, method 700 proceeds to Figure 7B Step 730 in. At 730, method 700 includes determining whether the actual needle tip position relative to the target location is suitable for performing a biopsy. In one example, this may include determining whether the user has confirmed that the selected biopsy needle is in a desired position relative to the target location for a biopsy.

[0142] In addition or alternatively, method 700 may include indicating whether the actual (current) needle tip position is in a desired position relative to the target position based on the second reconstruction error and the inserted needle parameters. For example, if the actual needle tip position is positioned so that the distance from the target position is greater than the threshold distance, the needle tip may not reach the target when fired, and therefore the target tissue may not be collected in the recess of the needle. The threshold distance may be based on the target position, the actual needle tip position, and needle parameters such as length and diameter. Therefore, the processor may indicate via the user interface that the needle tip position is not in a desired position for biopsy relative to the target position, and further, the processor may indicate that the distance between the actual needle tip and the target position is greater than the threshold distance. Although the above steps show whether the actual needle tip position relative to the target position is suitable for performing a biopsy based on user input, it should be understood that the determination of one or more of the actual tip position (from the pre-firing reconstruction image and based on the reconstruction error model), the target position (selected from the reconstruction image used for target positioning before the needle is inserted) and the tip position returned by the robot (where the tip is in the pre-firing position) is automatic and is also within the scope of the present disclosure.

[0143] If the needle tip position relative to the target position is not confirmed, the answer at 730 is no, and method 700 proceeds to 731, where the current biopsy procedure using the currently selected needle can be terminated. For example, based on the indication of the pre-firing parameters (at 716), the user can determine that the needle tip position is not in the desired position for biopsy. Therefore, it may be desirable to terminate the current biopsy procedure in order to evaluate whether a different approach (such as a horizontal approach if the current approach is a vertical biopsy approach) and / or a different needle may be more suitable for biopsy. Terminating the current biopsy procedure may include allowing the user to retract the needle without firing.

[0144] However, if the needle tip position relative to the target position for a subsequent biopsy is confirmed, the answer at 730 is yes, and the method 700 proceeds to 734. At 734, the method 700 includes transmitting the confirmation of the needle tip position to the needle holder control system. In response to receiving the confirmation of the needle tip position, the needle holder control system may adjust one or more actuators to allow the user to fire the biopsy needle, or automatically begin firing the biopsy needle to collect a biopsy sample. For example, when the needle tip position is in a desired position for a biopsy relative to the target position, the user may deploy the biopsy gun to fire the biopsy needle.

[0145] When the biopsy needle is fired, the needle firing may be detected by one or more sensors of the biopsy device and / or the x-ray system. At 735, in response to detecting the needle firing, method 700 includes obtaining a plurality of post-fire images in which the needle is in a post-fire position. The plurality of post-fire images may include a scout image obtained at zero degrees relative to the vertical axis of the x-ray system, and a stereoscopic scan obtained using an x-ray source at various angles (-θ to +θ) with the vertical axis within an angular range. For example, when the needle firing is confirmed, the needle is in a post-fire position, and the x-ray source may be rotated within the angular range of the x-ray system, and a plurality of images may be obtained with the needle in a post-fire position. As described above with respect to obtaining a pre-fire image, obtaining a plurality of post-fire images may include obtaining a plurality of post-fire scans and reconstructing a plurality of post-fire images based on the post-fire scans. In addition, after obtaining a plurality of post-fire images, method 700 may further include displaying a post-fire image with the needle in a post-fire position on a user interface.

[0146] Additionally, as discussed above with respect to the needle in the pre-fired position, it is possible (using Figure 8 The method 800 described herein evaluates the needle position at the post-fire stage and may indicate to the user the corresponding inserted needle parameters at the post-fire stage (as described in step 716). Since the evaluation of the needle in the post-fire position is similar to the evaluation of the needle in the pre-fire position described in detail above, the post-fire position evaluation will not be repeated.

[0147] In one example, evaluation of the needle in a post-fired position may be used to determine whether the needle has penetrated the target lesion and, therefore, assess the success of the biopsy.

[0148] Next, at 737, method 700 may include determining whether the tissue extraction is complete. For example, whether the tissue extraction is complete may be determined based on user confirmation. If the tissue extraction is not complete, the answer at 737 is no, and method 700 proceeds to 738 to monitor the completion of the tissue extraction. If the tissue extraction is complete, the answer at 737 is yes, and method 700 proceeds to 740.

[0149] When extracting tissue, the user may insert a post-biopsy clip to mark the biopsy site. Therefore, at 740, method 700 includes determining whether the post-biopsy clip is inserted. For example, confirmation of the post-biopsy clip insertion may be based on a user indication. If the post-biopsy insertion is not completed, the answer at 740 is no, and method 700 proceeds to 741 to monitor the post-biopsy clip insertion. If the post-biopsy clip is inserted, the answer at 740 is yes, and method 700 proceeds to 742. At 742, method 700 includes acquiring a plurality of post-firing images with the post-biopsy clip at the biopsy site. The plurality of post-firing images with the post-biopsy clip may include a scout image acquired at zero degrees relative to the vertical axis of the x-ray system, and a plurality of scans acquired with the x-ray source at various angles (-θ to +θ) with the vertical axis within an angular range. For example, upon confirming that the post-biopsy clip is inserted, the x-ray source may be rotated within the angular range of the x-ray system, and a plurality of images in which the post-biopsy clip has been inserted may be acquired. As described above with respect to obtaining pre-fire images and post-fire images, obtaining multiple post-fire images with a post-biopsy clip may include obtaining multiple post-fire scans and reconstructing multiple post-fire images based on the post-fire scans. In addition, method 700 includes displaying the post-fire image with the clip on a user interface.

[0150] In this way, based on the first reconstruction error and the second reconstruction error determined according to the error model, the accuracy and efficiency of biopsy can be improved.

[0151] Next, Fig. 9 Schematic diagram 900 showing exemplary observed needle tip volumes and shapes when a biopsy needle is bent during insertion into a pre-fired position and exemplary expected volumes and shapes of the needle tip when not bent. Specifically, Fig. 9 A portion of an x-ray system (such as x-ray system 100 in FIG. 1 ) is shown between compression paddle 902 and detector 904. A biopsy needle 950 is shown in volume 919 of a compressed breast. Biopsy needle 950 is oriented in a vertical approach mode, with a vertical needle axis along the length of the needle perpendicular to compression paddle 902 and detector 904. The angular range of the x-ray system is shown by arrow 906 and two angular positions of x-ray tube 920, −θ and +θ. A first cone beam of x-rays from x-ray tube 920 at the +θ position is shown by dashed line 940, and a second cone beam from x-ray tube 920 at the −θ position is shown by dashed line 945.

[0152] In this exemplary illustration, the actual needle 950 is shown positioned within the DBT volume 919 of the breast. An expected needle shape modeled based on an error model based on needle parameters, target position, and x-ray system parameters is shown at 935. The needle 950 may include a needle tip end 955. The actual needle tip portion of the needle 950 is shown by vertical hatching. However, when the needle is imaged within the DBT volume by moving the x-ray tube 920 at multiple angles within the angular range -θ to +θ and reconstructing a projection image of the x-rays projected onto the detector 904, the needle tip appears in the larger DBT volume along the z-axis (905) of the reconstructed image. Specifically, the needle tip end position 965 appears to be located at a different position than the actual needle tip position 955. The observed needle tip length is greater than the actual needle tip length, and due to the reduced resolution of DBT imaging in the z-direction, the needle tip is considered to be leaking in the vertical direction along the z-axis. Additionally, during insertion, the needle tip may have followed a curved trajectory due to bending, and thus the observed needle tip shape 975 is different from the expected needle tip shape 935. Therefore, by comparing the observed needle tip shape 975 and volume with the expected needle tip shape 935 and volume modeled based on the error model, it can be determined whether the needle has followed a straight trajectory or whether the needle tip has bent during insertion. Additionally, the amount of bending can be determined based on the comparison of the observed needle tip shape and volume with the modeled needle tip shape and volume.

[0153] If the actual needle 950 had followed a linear path, the expected needle tip shape 935 and volume may match the observed needle tip shape and volume, and the modeled needle tip may be used to determine the actual needle tip end. However, because the actual needle tip 950 follows a curved trajectory, to determine the actual needle tip position 955, the expected needle tip 935 modeled based on the error model may be adjusted so that the expected needle tip shape 935 and volume match the observed needle tip shape 975 and volume. When the expected needle tip shape and volume are adjusted to the observed needle tip shape and volume, the actual needle tip end position 955 may be inferred from the adjusted model. In addition, a leakage volume 956 may be determined based on the adjusted needle tip model and the observed needle tip.

[0154] In this way, the error model and the observed needle volume can be used to infer whether the actual needle was bent during insertion, and further determine the actual needle tip position. The actual needle tip position, the leakage volume of the actual needle tip volume, the amount of bending of the actual needle tip, and other needle parameters, such as the notch position, can be indicated to the user. Based on the above indications, the user may be able to more accurately visualize the actual needle tip position and determine whether the needle is in the desired position relative to the target location for biopsy.

[0155] A technical effect is that the error model allows the user to more accurately determine the actual interventional tool position. By implementing the error model, the user is able to perform interventional procedures with improved accuracy and efficiency, and in addition, the error model facilitates the user to make more accurate decision-making processes at various stages of the workflow. Therefore, the need to re-perform interventional procedures, for example due to non-extraction of target anomalies, is significantly reduced. Another technical effect of the error model is that the user can be informed of the expected reconstruction error even before starting the interventional procedure, and may be able to decide whether the expected reconstruction error is acceptable for a given interventional procedure, thereby improving efficiency and increasing the success rate of the interventional procedure.

[0156] Embodiments of a method for an x-ray system include: performing a digital breast tomosynthesis scan of a compressed breast with the x-ray system and generating tomosynthesis scan data; reconstructing an image of the compressed breast from the tomosynthesis scan data; and determining an expected reconstruction error of an interventional tool based on an error model modeled based on acquisition geometry of the x-ray system and interventional tool parameters; wherein the interventional tool parameters include tool length, tool tip diameter, tool orientation, and tool tip position derived from one or more of a selected target position in the reconstructed image and a tip position returned by a robot, the tip position returned by the robot being determined based on feedback from a robotic system coupled to the x-ray system. A first embodiment of the method includes: wherein the expected reconstruction error of the interventional tool is determined prior to inserting the interventional tool into the compressed breast. In a second embodiment of the method (which optionally includes the first embodiment), the interventional tool includes one or more of a biopsy needle, a hook wire, and an ablation needle; and wherein the acquisition geometry includes an angular range of the x-ray system, a source-to-image distance of the x-ray system, and a focal position of the x-ray system. In a third embodiment of the method, the third embodiment optionally includes one or more or each of the first and second embodiments, the method further includes displaying the expected reconstruction error on a user interface of the x-ray system. In a fourth embodiment of the method, the fourth embodiment optionally includes one or more or each of the first to third embodiments, the method further includes: identifying one or more candidate interventional tools from an interventional tool database having a corresponding reconstruction error less than a threshold error; and displaying the one or more candidate interventional tools on the user interface. In a fifth embodiment of the method, the fifth embodiment optionally includes one or more or each of the first to fourth embodiments, the method further includes: wherein the threshold error is based on one or more of the size of the selected target, the interventional tool parameters, and the user-selected settings. In a sixth embodiment of the method, the sixth embodiment optionally includes one or more or each of the first to fifth embodiments, the method includes: in response to the interventional tool being positioned within the compressed breast, performing a second tomosynthesis scan of the compressed breast with the interventional tool, and reconstructing a second image based on second scan data from the second tomosynthesis scan; determining an actual tool tip end position based on the tool tip shape and position observed from the second reconstructed image and the expected reconstruction error; and indicating the actual tool tip position on the second reconstructed image. In a seventh embodiment of the method, the seventh embodiment optionally includes one or more or each of the first to sixth embodiments, and the method also includes determining the tool tip displacement based on a comparison result of the observed tool tip shape and position in the second reconstructed image with the expected tool tip shape and position, and the expected tool tip shape and position are modeled based on the expected reconstruction error and the tool tip position.In an eighth embodiment of the method, the eighth embodiment optionally includes one or more or each of the first to seventh embodiments, the method further includes: wherein the comparison is performed using a similarity metric; and the method further includes indicating the tool tip displacement on a user interface.

[0157] One embodiment relates to a method for performing an image-guided interventional procedure using an x-ray system, the method comprising: when an interventional tool is inserted into the tissue, performing a tomosynthesis scan of the tissue with the interventional tool in the tissue, and reconstructing an image based on scan data from a second tomosynthesis scan; determining an expected reconstruction error for the interventional tool, the expected reconstruction error being based on a target position, an x-ray system geometry, and one or more interventional tool parameters; determining an observed tool tip shape based on the reconstructed image; determining an expected tool tip shape based on the tool tip position and the expected reconstruction error; determining a similarity metric between the observed tool tip shape and the expected tool tip shape; and determining an actual tool tip end position within a physical volume of the tissue based on the similarity metric. A first embodiment of the method includes: wherein when inserted, the tool is in a pre-fire position relative to the target position. In a second embodiment of the method, the second embodiment optionally includes the first embodiment, and also includes: wherein when inserted, the tool is in a post-fire position relative to the target position. In a third embodiment of the method, the third embodiment optionally includes one or both of the first and second embodiments, the method further includes: wherein the expected reconstruction error includes an estimated tool tip position difference between an actual tool tip position and an expected reconstructed tip position, the actual tool tip position being based on a target position, and the expected reconstructed tip position being based on the target position, the x-ray system geometry, and the one or more interventional tool parameters; and wherein the one or more interventional tool parameters include a desired orientation of the tool, a length of the tool tip, and a diameter of the tool tip. In a fourth embodiment of the method, the fourth embodiment optionally includes one or more or each of the first to third embodiments, the method further includes: displaying the reconstructed image on a user interface; indicating one or more of an expected tool tip position, an actual tool tip position, and a leakage region of a selected interventional tool on the reconstructed image containing the tool, and displaying the expected reconstruction error on the user interface; wherein the leakage region is based on the expected reconstruction error. In a fifth embodiment of the method, the fifth embodiment optionally includes one or more or each of the first to fourth embodiments, the method further includes: determining a tool displacement based on a similarity metric, and displaying the tool displacement on the user interface. In a sixth embodiment of the method, the sixth embodiment optionally includes one or more or each of the first to fifth embodiments, the method comprising: determining a sensor-based tool tip position of the tool when the tool is inserted into tissue; and adjusting the determined actual tool tip position information based on the sensor-based tool tip position; wherein the sensor-based tool tip position is determined based on the axis position of a robotic tool for mounting and guiding the interventional tool, a geometric model of the robotic tool, interventional tool parameters, and calibration parameters of the interventional tool.

[0158] An embodiment of a system for an imaging system includes: a radiation source that rotates around an axis of the imaging system within an angular range; a detector for receiving radiation rays from the radiation source and generating a plurality of projection images of a sample positioned between the radiation source and the detector; a biopsy device including a biopsy tool system and an interventional tool coupled to the biopsy tool system, the biopsy device coupled to the imaging system and positioned between the radiation source and the detector; and an imaging processor having executable instructions stored in a non-transitory memory for: reconstructing a plurality of projection images of the sample without the tool inserted from a first digital breast tomosynthesis scan; determining an expected reconstruction error of the tool based on a selected target biopsy location in the reconstructed image, an x-ray system geometry, and tool parameters including a tool diameter and a tool length; and displaying the expected reconstruction error on a user interface of the imaging system. In a first embodiment of the system, the imaging system further includes: wherein the expected reconstruction error includes an expected leakage of the tool tip image within an imaging volume of the x-ray system. In a second embodiment of the imaging system, the second embodiment optionally includes the first embodiment, the processor includes additional instructions in the non-transitory memory for the following operations: generating a second set of images by reconstructing a plurality of second projection images of the specimen with the tool inserted, the plurality of second projection images being obtained from a second digital breast tomosynthesis scan performed using the imaging system; determining an observed tool tip image from the second image; determining one or more of an actual tool tip position, an actual tool tip shape, a reconstruction error region, and an amount of bending of the tool based on an expected position and an expected shape of the tool tip modeled based on an expected reconstruction error and based on an observed position and an observed shape of the observed tool tip image; and indicating the actual tool tip position and the reconstruction error region on the second image displayed on the user interface; and displaying the amount of bending on the user interface. In a third embodiment of the imaging system, the third implementation optionally includes the first embodiment and the second embodiment, the imaging system includes: wherein the tool is a needle; and wherein the processor further includes instructions for the following operations: determining an actual notch position of the needle based on an observed needle tip shape and an observed needle tip position from a tomosynthesis reconstructed image of the needle and a corresponding expected reconstruction error of the needle.

[0159] When introducing the elements of various embodiments of the present disclosure, the words "one", "a kind of" and "the" are intended to mean that there are one or more elements in these elements. The terms "first", "second", etc. do not represent any order, amount or importance, but are used to distinguish one element from another element. The terms "comprise", "include" and "have" are intended to be inclusive, and mean that additional elements may also exist in addition to the listed elements. As used herein, the terms "connected to", "connected to", etc., an object (e.g., material, element, structure, member, etc.) can be connected to or connected to another object, regardless of whether the one object is directly connected or connected to another object, or whether there are one or more intervening objects between the one object and another object. In addition, it should be understood that reference to "one embodiment" or "embodiment" of the present disclosure is not intended to be interpreted as excluding the existence of additional embodiments that also include the cited features.

[0160] In addition to any previously indicated modifications, numerous other variations and alternative arrangements may be devised by those skilled in the art without departing from the spirit and scope of the present description, and the appended claims are intended to cover such modifications and arrangements. Therefore, although the information has been described above in detail in conjunction with what are currently considered to be the most practical and preferred aspects, it will be apparent to those of ordinary skill in the art that many modifications may be made, including but not limited to form, function, mode of operation, and use, without departing from the principles and concepts set forth herein. Likewise, as used herein, the examples and embodiments are intended to be illustrative in all respects only and should not be construed as limiting in any way.

Claims

1. A method for an X-ray system, comprising: performing a digital breast tomosynthesis scan of the compressed breast using the X-ray system and generating tomosynthesis scan data; reconstructing an image of the compressed breast based on the tomosynthesis scan data; as well as determining an expected reconstruction error of the interventional tool based on an error model modeled according to the acquisition geometry of the X-ray system and interventional tool parameters; The interventional tool parameters include tool length, tool tip diameter, tool orientation and tool tip position, wherein the tool tip position is derived from one or more of a target position selected in the image and a tip position returned by the robot, wherein the tip position returned by the robot is determined based on feedback from a robotic system connected to the X-ray system.

2. The method of claim 1, wherein the expected reconstruction error of the interventional tool is determined before the interventional tool is inserted into the compressed breast.

3. The method of claim 1, wherein the interventional tool comprises one or more of a biopsy needle, a hook wire, and an ablation needle; and wherein, The acquisition geometry includes the angular range of the X-ray system, the source-to-image distance of the X-ray system, and the focal position of the X-ray system. 4 . The method of claim 1 , further comprising displaying the expected reconstruction error on a user interface of the X-ray system.

5. The method according to claim 1, further comprising: identifying one or more candidate interventional tools from an interventional tool database having corresponding reconstruction errors less than a threshold error; and displaying the one or more candidate interventional tools on a user interface.

6. The method of claim 5, wherein the threshold error is based on one or more of a size of a selected target, the interventional tool parameters, and a user-selected setting.

7. The method according to claim 1, further comprising: In response to the interventional tool being positioned within the compressed breast, performing a second tomosynthesis scan of the compressed breast with the interventional tool, and reconstructing a second image based on second scan data from the second tomosynthesis scan; determining an actual tool tip end position based on the tool tip shape and position observed from the second image and the expected reconstruction error; as well as The actual tool tip position is indicated on the second image.

8. The method of claim 7 further comprises determining a tool tip displacement amount based on a comparison of the observed tool tip shape and position in the second image with an expected tool tip shape and position, wherein the expected tool tip shape and position is modeled based on the expected reconstruction error and the tool tip position.

9. The method of claim 8, wherein the comparing is performed using a similarity metric; and the method further comprises indicating the tool tip displacement amount on a user interface.

10. A method for performing an image-guided interventional procedure using an X-ray system, comprising: When an interventional tool is inserted into tissue, performing a tomosynthesis scan of the tissue with the interventional tool in the tissue and reconstructing an image based on scan data from the tomosynthesis scan; determining an expected reconstruction error of the interventional tool, the expected reconstruction error being based on a target position, an X-ray system geometry, and one or more interventional tool parameters; determining an observed tool tip shape based on the image; determining an expected tool tip shape based on the tool tip position and the expected reconstruction error; determining a similarity measure between the observed tool tip shape and the expected tool tip shape; as well as An actual tool tip end position within the physical volume of tissue is determined based on the similarity metric.

11. A method according to claim 10, wherein the expected reconstruction error includes an estimated tool tip position difference between an actual tool tip position and an expected tool tip position, wherein the actual tool tip position is based on the target position, and the expected tool tip position is based on the target position, the X-ray system geometry, and the one or more interventional tool parameters; and wherein the one or more interventional tool parameters include a desired orientation of the tool, a tool tip length, and a tool tip diameter.

12. The method according to claim 11 also includes displaying the image on a user interface; indicating one or more of the expected tool tip position, the actual tool tip position and the leakage area of ​​the selected interventional tool on the image containing the tool, and displaying the expected reconstruction error on the user interface; wherein the leakage area is based on the expected reconstruction error.

13. The method according to claim 10 also includes determining a sensor-based tool tip position of the tool when the tool is inserted into the tissue; and adjusting the determined actual tool tip position information based on the sensor-based tool tip position; wherein the sensor-based tool tip position is determined based on the axis position of a robotic tool used to install and guide the interventional tool, a geometric model of the robotic tool, the interventional tool parameters and calibration parameters of the interventional tool.

14. An imaging system comprising: a radiation source that rotates within an angular range about an axis of the imaging system; a detector for receiving radiation rays from the radiation source and generating a plurality of projection images of a sample positioned between the radiation source and the detector; a biopsy device comprising a biopsy tool system and an interventional tool coupled to the biopsy tool system, the biopsy device coupled to the imaging system and positioned between the radiation source and the detector; and An imaging processor having executable instructions stored in non-transitory memory for: reconstructing a plurality of projection images of the specimen without the tool inserted from a first digital breast tomosynthesis scan; determining an expected reconstruction error of the tool based on a selected target biopsy location in the reconstructed plurality of projection images, an X-ray system geometry, and tool parameters including a tool diameter and a tool length; and The expected reconstruction error is displayed on a user interface of the imaging system.

15. The imaging system of claim 14, wherein the processor includes further instructions in non-transitory memory for: generating a second image by reconstructing a plurality of second projection images of the specimen with the tool inserted, the plurality of second projection images obtained from a second digital breast tomosynthesis scan performed using the imaging system; determining an observed tool tip image based on the second image; determining one or more of an actual tool tip position, an actual tool tip shape, a reconstruction error region, and an amount of bending of the tool based on an expected position and an expected shape of the tool tip modeled according to the expected reconstruction error and based on an observed position and an observed shape of the observed tool tip image; and indicating the actual tool tip position and the reconstruction error region on the second image displayed on the user interface; And displaying the bending amount on the user interface.

Images