Systems and methods for x-ray imaging and targeted x-ray therapy

Abstract

An X-ray therapy method using an X-ray device includes: arranging the cathode device of an X-ray source in an imaging mode to focus electrons onto a focal region of a first size on the anode. In imaging mode, the X-ray source is actuated to emit an X-ray beam toward an X-ray detector to obtain a first X-ray image of a target. Based on a comparison of the first X-ray image and a diagnostic image, the X-ray source or object is adjusted to register the target with its diagnostic image, and the X-ray source is directed toward the target. The cathode device is switched to a power mode to focus electrons onto a second focal region of a second size on the anode, which is larger than the first size. In power mode, the X-ray source is actuated to deliver a therapeutic X-ray dose to the target.

Description

background Technical Field

[0001] This disclosure relates to X-ray imaging and therapy, and more specifically, to systems and methods for X-ray imaging and targeted X-ray therapy. Background Technology

[0002] Radiation therapy (RT) is generally considered an effective treatment option for local control of tumors. Many cancer patients include RT as part of their overall cancer management plan. However, despite its ability to kill cancer cells, RT does not always produce successful results. This is often due to the fact that the radiation dose required to eradicate a tumor can cause significant damage to surrounding healthy tissues in both the short and long term.

[0003] Significant technological advancements have been made in radiotherapy in recent years, particularly in precise tumor coverage and minimizing exposure to healthy tissues during treatment planning and delivery. As a result, cancer patients now have access to conformal and intensity-modulated radiotherapy (IMRT) as well as imaging-guided radiotherapy (IGRT).

[0004] While state-of-the-art radiation therapy offers promising benefits to many cancer patients, these benefits are often limited by the necessity of high radiation doses that can cause intolerable damage to critical structures near the tumor site. Furthermore, current radiation therapy techniques may be less effective in pediatric patients, whose developing, normal tissues are often more sensitive to radiation than their tumors. Therefore, pediatric patients often cannot tolerate radiation therapy doses that are curable for adults with the same disease.

[0005] An alternative treatment called spatially fractionated radiotherapy (SFRT) has shown promise in improving the preservation of normal tissue and has produced encouraging results. In conventional radiotherapy, wide, continuous beams of radiation are typically used to treat cancer. In contrast, SFRT employs specialized radiation characterized by unique spatial, temporal, and radiation dose patterns. In SFRT, the radiation field is discrete and consists of beams ranging in width from tens of micrometers to several millimeters or even centimeters. The spacing between adjacent beams is typically several times the width of the beam itself (e.g., 2–10 times).

[0006] Several SFRT techniques, such as grid radiation therapy, flash radiation therapy, lattice radiation therapy (LRT), and microbeam radiation therapy (MRT), are currently under investigation in preclinical studies, and some early clinical experience is available. The primary goals of these SFRT techniques are generally to achieve improved tumor control and reduced damage to healthy tissues. While shared mechanisms may exist, our understanding of these mechanisms is currently limited. The bystander effect, abscopal effect, vascular injury, angiogenesis, and immune responses are all considered potential factors. Despite the potential of SFRT as a cost-effective cancer treatment, it has not been widely adopted in clinical practice, primarily due to the lack of efficient radiation delivery systems.

[0007] Currently, most SFRT treatments are performed using conventional linear radiotherapy accelerators (LINACs). The dose rate of state-of-the-art LINAC machines is approximately 5 g / min. Recently, a form of SFRT treatment called flash radiotherapy has been found to produce encouraging results. However, it requires a relatively high radiation dose rate (e.g., exceeding 40 Gy / sec) during treatment delivery. This order of magnitude of dose rate cannot be achieved with existing LINACs. Furthermore, clinical LINACs typically produce megavolt (MV) range X-rays, which are unsuitable for SFRT treatment due to the large footprint of high-energy MV radiation leading to poor dose distribution. Studies have shown that high kV range X-ray radiation (e.g., several hundred kV: 160 kV–800 kV) is preferred for SFRT treatment.

[0008] Meanwhile, SFRT has been demonstrated using proton therapy and synchrotron-based systems. These advanced machines can deliver SFRT treatment at high dose rates with acceptable dose distribution. However, such machines are relatively expensive. The average cost of a proton therapy machine exceeds $50 million, and the average cost of a synchrotron facility exceeds $100 million. The high cost of such systems significantly hinders their clinical use.

[0009] In some cases, conventional X-ray sources have also been considered for use in SFRT treatment. For example, as... Figure 1As shown, a conventional X-ray source comprises an electron cathode and an X-ray anode. The anode carries a high voltage, such as up to several hundred kV. Electrons emitted from the cathode are accelerated to high energies by the anode voltage and used to bombard a region (focal spot) on the anode to generate X-ray radiation. Some X-ray sources may have focusing electrodes to adjust / control the size of the focal spot on the anode. However, the radiation dose rate of conventional X-ray sources is relatively low. One reason for the relatively low dose rate is that such conventional X-ray sources are typically designed for imaging applications that require relatively small focal spot sizes (e.g., sub-millimeter to several millimeters in diameter). Small focal spots are preferred for providing high-resolution imaging (e.g., small focal spot sizes provide a higher pixel count proportional to the desired resolution). However, for example, the small focal spot size also limits the maximum output power (dose rate) of the X-ray source due to the thermal limit of the small focal spot. Many conventional X-ray sources can only operate at relatively low currents (e.g., in the mA range). Some high-power X-ray sources (e.g., with rotating anodes) are designed to operate at high peak power (e.g., up to 100 kW), but are typically limited to relatively short exposure times (e.g., 10 ms) and low duty cycles (e.g., a few percent).

[0010] X-ray sources with relatively large focal spot sizes or focal lines (e.g., up to 10 cm) are required to deliver the power (dose rate) needed for SFRT therapy (especially flash radiotherapy). Some conventional X-ray sources have (electrostatic or magnetic) electron beam focusing / defocusing mechanisms to adjust the focal spot size on the anode, such as... Figure 1 As shown in the diagram. However, the range of focal spot sizes and configurations achievable through such focusing / defocusing mechanisms are typically very limited (2-3 times the size range).

[0011] Furthermore, modern radiotherapy requires image guidance to accurately deliver radiation doses to the tumor. For SFRT therapy, image guidance during treatment is even more critical due to the small size of the radiation field (as small as tens of micrometers) and the high dose rate (e.g., flash radiotherapy requires a dose rate >40 Gy / sec). For some existing SFRT systems, image guidance is typically achieved through additional, separate, and discrete imaging devices, often a separate X-ray imaging unit combined with the radiotherapy equipment. These imaging devices typically generate images from a direction different from the treatment beam emitted by the radiotherapy equipment, often orthogonal to the treatment beam, which is not ideal for image guidance and target tracking. Such arrangements also complicate the overall system design and increase system cost.

[0012] Therefore, there is a need for an X-ray radiation therapy system that is suitable for and capable of both radiation therapy and imaging functions, with minimal configuration changes between the two operating modes. Such an X-ray radiation therapy system should include an X-ray source with a cathode device capable of operating in imaging mode, where a small focal spot on the anode can be used to generate high-resolution images, and capable of operating in treatment mode, where a large focal spot / line on the anode can be used to achieve the high radiation dose rate required for cancer treatment. Such an X-ray radiation therapy system should also include imaging guidance and feedback capabilities before and / or during the radiation therapy phase to determine that one or more radiation doses are accurately delivered to the correct target location, so that minimal healthy tissue is subjected to radiation therapy. Summary of the Invention

[0013] To satisfy the above and other needs, this disclosure provides, in one aspect, a method for providing multimodal X-ray therapy to a target within an object using an X-ray apparatus including an X-ray source and an X-ray detector, wherein the X-ray source includes an anode and a field emission cathode device spaced apart from the anode and arranged to emit electrons toward the anode, and wherein the target is determined based on diagnostic imaging of the object and the diagnostic image of the target is obtained through diagnostic imaging of the object. Such methods include: arranging a field emission cathode device of an X-ray source in an imaging mode to focus electrons onto a first focal region on an anode, the first focal region having a first focal region size; imaging a target by actuating the X-ray source in the imaging mode to emit an imaging X-ray beam toward an X-ray detector, such that the imaging X-ray beam interacts with the target to obtain a first X-ray image of the target; adjusting the X-ray source or object in response to a comparison of the first X-ray image of the target and a diagnostic image of the target to register the target with the diagnostic image of the target and to guide the X-ray source toward the target; switching the arrangement of the field emission cathode device to a power mode to focus electrons onto a second focal region on an anode, the second focal region having a second focal region size larger than the first focal region size; and actuating the X-ray source in a power mode to emit a first therapeutic X-ray beam toward the target to deliver a first X-ray dose to the target.

[0014] Another aspect of this disclosure provides a multimodal X-ray system for delivering X-ray therapy to a target within an object, wherein the target is determined based on diagnostic imaging of the object and the diagnostic image of the target is obtained through diagnostic imaging of the object. Such an X-ray system includes: an X-ray detector; an X-ray source including an anode and a field emission cathode device spaced apart from the anode and arranged to emit electrons toward the anode; and a controller communicating with the X-ray source and the X-ray detector. The controller is configured to: guide an X-ray source to arrange a field emission cathode device in an imaging mode, thereby focusing electrons onto a first focal region on the anode, the first focal region having a first focal region size; image a target by actuating the X-ray source in the imaging mode to emit an imaging X-ray beam, such that the imaging X-ray beam interacts with the target and is detected by an X-ray detector to obtain a first X-ray image of the target; adjust the X-ray source or the target in response to a comparison of the first X-ray image of the target and a diagnostic image of the target to register the target with the diagnostic image of the target, and guide the X-ray source toward the target; guide the X-ray source to switch the arrangement of the field emission cathode device to a power mode, thereby focusing electrons onto a second focal region on the anode, the second focal region having a second focal region size larger than the first focal region size; and actuate the X-ray source in a power mode to emit a first therapeutic X-ray beam toward the target to deliver a first X-ray dose to the target.

[0015] Another aspect of this disclosure provides a method for providing a multi-mode X-ray source device, wherein the X-ray source device includes an anode and a field emission cathode device, the field emission cathode device being spaced apart from the anode and arranged to emit electrons toward the anode. Such a method includes: arranging the field emission cathode device in an imaging mode to focus electrons onto a first focal region on the anode, the first focal region having a first focal region size; and reversibly switching the arrangement of the field emission cathode device to a power mode to focus electrons onto a second focal region on the anode, wherein the second focal region has a second focal region size larger than the first focal region size.

[0016] Another aspect of this disclosure provides a multimode X-ray source apparatus comprising: an anode; and a field emission cathode apparatus spaced apart from the anode and arranged to emit electrons toward the anode, wherein the field emission cathode apparatus is switchable between an imaging mode and a power mode, the imaging mode focusing electrons onto a first focal region on the anode having a first focal region size, and the power mode focusing electrons onto a second focal region on the anode, wherein the second focal region has a second focal region size larger than the first focal region size.

[0017] This disclosure includes, but is not limited to, the following exemplary embodiments: Example 1: A method for providing multimodal X-ray therapy to a target within an object using an X-ray device, the X-ray device including an X-ray source and an X-ray detector, wherein the X-ray source includes an anode and a field emission cathode device, the field emission cathode device being spaced apart from the anode and arranged to emit electrons toward the anode, and wherein the target is determined based on diagnostic imaging of the object and the diagnostic image of the target is obtained through diagnostic imaging of the object, the method comprising: arranging the field emission cathode device of the X-ray source in an imaging mode to focus electrons onto a first focal region on the anode, the first focal region having a first focal region size; and actuating the X-ray source in the imaging mode to... An imaging X-ray beam is emitted toward an X-ray detector to image a target, such that the imaging X-ray beam interacts with the target to obtain a first X-ray image of the target; in response to a comparison of the first X-ray image of the target and a diagnostic image of the target, the X-ray source or object is adjusted to register the target with the diagnostic image of the target and to guide the X-ray source toward the target; the arrangement of the field emission cathode device is switched to a power mode to focus electrons on a second focal region on the anode, the second focal region having a second focal region size larger than the first focal region; and the X-ray source is actuated in power mode to emit a first therapeutic X-ray beam toward the target to deliver a first X-ray dose to the target.

[0018] Example 2: A method as described in any of the foregoing example embodiments or combinations thereof, comprising: after delivering a first X-ray dose to a target, switching the arrangement of the field emission cathode device of the X-ray source to an imaging mode; re-imaging the target using the X-ray device to obtain a second X-ray image of the target; adjusting the X-ray source or object in response to a comparison of the second X-ray image of the target and a diagnostic image of the target for registering the target with the diagnostic image of the target and for guiding the X-ray source toward the target; switching the arrangement of the field emission cathode device to a power mode to focus electrons on a second focal region on the anode; and actuating the X-ray source in a power mode to emit a second therapeutic X-ray beam toward the target to deliver the second X-ray dose to the target.

[0019] Example 3: A method as described in any of the foregoing example embodiments or combinations thereof, including: arranging an X-ray detector opposite to the X-ray source when the field emission cathode device of the X-ray source is in transmission imaging mode.

[0020] Example 4: A method as described in any of the foregoing example embodiments or combinations thereof, including: arranging an X-ray detector adjacent to the X-ray source when the field emission cathode device of the X-ray source is in backscatter imaging mode.

[0021] Example 5: A method as described in any of the foregoing example embodiments or combinations thereof, comprising: when the field emission cathode device of the X-ray source is in power mode, arranging the X-ray detector to not receive the first therapeutic X-ray beam or the second therapeutic X-ray beam.

[0022] Example 6: As in any of the foregoing example embodiments or combinations thereof, adjusting the X-ray source or object includes adjusting the distance between the X-ray source and the object, adjusting the angular position of the X-ray source in an orbit around the object, or adjusting the position of the X-ray source or object laterally and not parallel to the imaging X-ray beam relative to the other.

[0023] Example 7: A method as described in any of the foregoing example embodiments or combinations thereof, wherein the edge of the target is determined based on diagnostic imaging, and wherein the method includes collimating a first therapeutic X-ray beam or a second therapeutic X-ray beam emitted by an X-ray source in power mode such that the lateral dimension of the respective first therapeutic X-ray beam and the second therapeutic X-ray beam is not greater than the lateral dimension of the edge of the target perpendicular to the respective first therapeutic X-ray beam and the second therapeutic X-ray beam.

[0024] Example 8: As in any of the foregoing example embodiments or combinations thereof, wherein collimating the first therapeutic X-ray beam or the second therapeutic X-ray beam comprises using a slit collimator to collimate the first therapeutic X-ray beam or the second therapeutic X-ray beam emitted by the X-ray source in power mode, such that the first therapeutic X-ray beam or the second therapeutic X-ray beam is emitted onto the target as a linear region.

[0025] Example 9: As in any of the foregoing example embodiments or combinations thereof, wherein actuating an X-ray source in power mode to deliver a first X-ray dose or a second X-ray dose to a target comprises: actuating an X-ray source in power mode to deliver a first X-ray dose or a second X-ray dose to a target at a predetermined X-ray dose rate for a predetermined time, thereby providing a cumulative X-ray dose to the target.

[0026] Example 10: A method as described in any of the foregoing example embodiments or combinations thereof, including: performing imaging and re-imaging of a target using the same X-ray source and delivering a first X-ray dose and a second X-ray dose.

[0027] Example 11: A method as described in any of the foregoing example embodiments or combinations thereof, comprising: using a cone beam collimator to collimate a first imaging X-ray beam or a second imaging X-ray beam emitted from an X-ray source in imaging mode, such that the first imaging X-ray beam or the second imaging X-ray beam is emitted onto an object as an elliptical or circular region.

[0028] Example 12: A method as described in any of the foregoing example embodiments or combinations thereof, comprising: tracking the movement of an object during the delivery of a first X-ray dose; and adjusting the X-ray source or the object in response to the tracked movement of the object for registering the target with a diagnostic image of the target, and for maintaining the X-ray source pointing toward the target.

[0029] Example 13: A multimode X-ray system for providing X-ray therapy to a target within an object, the target being determined based on diagnostic imaging of the object and the diagnostic image of the target being obtained through diagnostic imaging of the object, the X-ray system comprising: an X-ray detector; an X-ray source including an anode and a field emission cathode device, the field emission cathode device being spaced apart from the anode and arranged to emit electrons toward the anode; and a controller communicating with the X-ray source and the X-ray detector, the controller being configured to: guide the X-ray source to arrange the field emission cathode device in an imaging mode, thereby focusing electrons onto a first focal region on the anode, the first focal region having a first focal region size; and through the imaging mode The X-ray source is actuated to emit an imaging X-ray beam to image a target, such that the imaging X-ray beam interacts with the target and is detected by an X-ray detector to obtain a first X-ray image of the target; in response to a comparison of the first X-ray image of the target and a diagnostic image of the target, the X-ray source or object is adjusted to register the target with the diagnostic image of the target, and the X-ray source is directed toward the target; the X-ray source is directed to switch the arrangement of the field emission cathode device to a power mode, thereby focusing electrons on a second focal region on the anode, the second focal region having a second focal region size larger than the first focal region; and the X-ray source is actuated in power mode to emit a first therapeutic X-ray beam toward the target to deliver a first X-ray dose to the target.

[0030] Example 14: A system as described in any of the foregoing example embodiments or combinations thereof, wherein the controller is configured to: after a first X-ray dose is delivered to the target, guide the X-ray source to switch the arrangement of the field emission cathode device to an imaging mode; re-image the target using the X-ray device to obtain a second X-ray image of the target; adjust the X-ray source or object in response to a comparison of the second X-ray image of the target and a diagnostic image of the target to register the target with the diagnostic image of the target, and guide the X-ray source toward the target; guide the X-ray source to switch the arrangement of the field emission cathode device to a power mode, thereby focusing electrons on a second focal region on the anode; and actuate the X-ray source in power mode to emit a second therapeutic X-ray beam toward the target to deliver a second X-ray dose to the target.

[0031] Example 15: A system as described in any of the foregoing example embodiments or combinations thereof, wherein when the field emission cathode device of the X-ray source is in transmission imaging mode, the X-ray detector is arranged opposite to the X-ray source.

[0032] Example 16: A system as described in any of the foregoing example embodiments or combinations thereof, wherein when the field emission cathode device of the X-ray source is in backscatter imaging mode, the X-ray detector is arranged adjacent to the X-ray source.

[0033] Example 17: A system as described in any of the foregoing example embodiments or combinations thereof, wherein when the field emission cathode device of the X-ray source is in power mode, the X-ray detector is arranged not to receive the first therapeutic X-ray beam or the second therapeutic X-ray beam.

[0034] Example 18: A system as described in any of the foregoing example embodiments or combinations thereof, wherein the controller is configured to adjust the X-ray source or object by: adjusting the distance between the X-ray source and the object, adjusting the angular position of the X-ray source in an orbit around the object, or adjusting the position of the X-ray source or object laterally and not parallel to the imaging X-ray beam relative to the other.

[0035] Example 19: A system as described in any of the foregoing example embodiments or combinations thereof, wherein the edge of the target is determined based on diagnostic imaging, and wherein the system includes a collimator disposed between an X-ray source and the object, the collimator being configured to collimate a first therapeutic X-ray beam or a second therapeutic X-ray beam emitted by the X-ray source in power mode such that the lateral dimension of the respective first therapeutic X-ray beam and the second therapeutic X-ray beam is not greater than the lateral dimension of the edge of the target perpendicular to the respective first therapeutic X-ray beam and the second therapeutic X-ray beam.

[0036] Example 20: A system as described in any of the foregoing example embodiments or combinations thereof, wherein the collimator includes a slit beam collimator configured to collimate a first therapeutic X-ray beam or a second therapeutic X-ray beam emitted by an X-ray source in power mode, such that the first therapeutic X-ray beam or the second therapeutic X-ray beam is emitted onto the target as a linear region.

[0037] Example 21: A system as described in any of the foregoing example embodiments or combinations thereof, wherein the controller is configured to actuate an X-ray source in power mode to deliver a first X-ray dose or a second X-ray dose to a target at a predetermined X-ray dose rate for a predetermined time, thereby providing a cumulative X-ray dose to the target.

[0038] Example 22: A system as described in any of the foregoing example embodiments or combinations thereof, wherein the imaging and re-imaging of the target and the delivery of the first and second X-ray doses are performed using the same X-ray source.

[0039] Example 23: A system as described in any of the foregoing example embodiments or combinations thereof includes a cone-beam collimator disposed between an X-ray source and an object, and configured to collimate a first imaging X-ray beam or a second imaging X-ray beam emitted by the X-ray source in imaging mode, such that the first imaging X-ray beam or the second imaging X-ray beam is emitted onto the object as an elliptical or circular region.

[0040] Example 24: A system as described in any of the foregoing example embodiments or combinations thereof includes a tracking device that communicates with a controller and is configured to track the movement of an object during the delivery of a first X-ray dose, wherein the controller is configured to adjust the X-ray source or the object in response to the tracked movement of the object for registering the target with a diagnostic image of the target and for maintaining the X-ray source pointing toward the target.

[0041] Example 25: A method for providing a multi-mode X-ray source device, the X-ray source device including an anode and a field emission cathode device, the field emission cathode device being spaced apart from the anode and arranged to emit electrons toward the anode, the method comprising: arranging the field emission cathode device in an imaging mode to focus electrons onto a first focal region on the anode, the first focal region having a first focal region size; and reversibly switching the arrangement of the field emission cathode device to a power mode to focus electrons onto a second focal region on the anode, the second focal region having a second focal region size larger than the first focal region size.

[0042] Example 26: A method as described in any of the foregoing example embodiments or combinations thereof, wherein the field emission cathode device includes a plurality of individually controllable field emission cathodes, and wherein arranging the field emission cathode device in an imaging mode includes actuating a first amount of field emission cathodes to guide electrons emitted by the first amount of field emission cathodes to a first focal region on the anode.

[0043] Example 27: A method as described in any of the foregoing example embodiments or combinations thereof, wherein the field emission cathode device includes a plurality of individually controllable field emission cathodes, and wherein switching the arrangement of the field emission cathode device to a success rate mode includes actuating a second amount of field emission cathodes to guide electrons emitted by the second amount of field emission cathodes to a second focal region, the second amount being greater than the first amount.

[0044] Example 28: The method as described in any of the foregoing example embodiments or combinations thereof, wherein guiding electrons to the second focal region comprises guiding electrons from each of the second amount of field emission cathodes to a corresponding corresponding focal region on the anode, the corresponding corresponding focal regions being disposed adjacently and arranged to form a second focal region on the anode.

[0045] Example 29: A method as described in any of the foregoing example embodiments or combinations thereof, wherein each of the second amount of field emission cathodes emits an electron current directed toward the anode upon actuation, and wherein the method includes: modulating the current emitted by one or more selected field emission cathodes of the second amount of field emission cathodes to modulate the intensity of electrons emitted by the selected one or more field emission cathodes to the second focal region.

[0046] Example 30: A multi-mode X-ray source device, comprising: an anode; and a field emission cathode device spaced apart from the anode and arranged to emit electrons toward the anode, the field emission cathode device being switchable between an imaging mode and a power mode, wherein the imaging mode focuses electrons onto a first focal region on the anode, the first focal region having a first focal region size, and the power mode focuses electrons onto a second focal region on the anode, the second focal region having a second focal region size larger than the first focal region size.

[0047] Example 31: A device as described in any of the foregoing example embodiments or combinations thereof, wherein the field emission cathode device includes a plurality of individually controllable field emission cathodes configured such that the imaging mode includes a first amount of field emission cathodes, the first amount of field emission cathodes being actuated to guide electrons emitted by the first amount of field emission cathodes to a first focal region on the anode.

[0048] Example 32: A device as described in any of the foregoing example embodiments or combinations thereof, wherein the field emission cathode device is configured such that the power mode includes a second amount of field emission cathode, the second amount being greater than the first amount, the second amount of field emission cathode being actuated to guide electrons emitted by the second amount of field emission cathode to a second focal region.

[0049] Example 33: A device as described in any of the foregoing example embodiments or combinations thereof, wherein a second amount of field emission cathodes is arranged to guide electrons emitted by the second amount of field emission cathodes to a corresponding corresponding focal region on the anode, the corresponding corresponding focal regions being arranged adjacently and to form a second focal region on the anode.

[0050] Example 34: A device as described in any of the foregoing example embodiments or combinations thereof, wherein each of the second amount of field emission cathodes emits an electron current directed toward the anode upon its actuation, and wherein the electron current emitted by one or more selected field emission cathodes of the second amount of field emission cathodes can be modulated to modulate the intensity of electrons emitted by the selected one or more field emission cathodes to the second focal region.

[0051] These and other features, aspects, and advantages of this disclosure will be apparent from reading the following detailed description together with the accompanying drawings briefly described below. This disclosure includes any combination of two, three, four, or more features or elements set forth in this disclosure, whether or not such features or elements are explicitly combined or otherwise described in the particular embodiments described herein. This disclosure is intended to be read in its entirety such that, unless the context of this disclosure explicitly indicates otherwise, any separable features or elements in any aspect and embodiment of this disclosure should be considered as contemplated (i.e., combinable).

[0052] It will be understood that the inventive summary herein is provided only for the purpose of outlining some exemplary aspects in order to provide a basic understanding of this disclosure. Therefore, it will be understood that the exemplary aspects described above are merely illustrative and should not be construed as limiting the scope or spirit of this disclosure in any way. It will be understood that the scope of this disclosure covers many potential aspects, some of which will be further described below in addition to those outlined herein. Furthermore, other aspects and advantages of such aspects disclosed herein will become apparent from the following detailed description taken in conjunction with the accompanying drawings, which illustrate the principles of the described aspects by way of example. Attached Figure Description

[0053] The present disclosure has been described in summary as follows, with reference now to the accompanying drawings, which are not necessarily drawn to scale, and in which: Figure 1 The schematic diagram illustrates a typical example of a prior art X-ray source, including a metal anode (tungsten, molybdenum, etc.), an electron cathode, and, in some examples, an electron focusing electrode. Figure 2A and Figure 2B The schematic diagram illustrates an X-ray source according to one aspect of the present disclosure, wherein a field emission cathode device includes a plurality of individually controllable field emission cathodes, wherein one of the field emission cathodes can be actuated to provide imaging X-rays from a first viewing angle. Figure 2A ), and then the field emission cathode is de-actuated and another field emission cathode is actuated to provide imaging X-rays from different angles ( Figure 2B ); Figure 3 Schematic map shows Figure 2A and Figure 2B The X-ray source shown according to this aspect of the disclosure can be sequentially actuated in various field emission cathodes (or small groups of field emission cathodes) to provide imaging X-rays from multiple viewpoints; Figure 4A The schematic diagram illustrates an X-ray source according to one aspect of the present disclosure, wherein the field emission cathode device includes a plurality of individually controllable field emission cathodes, wherein many (or all) of the field emission cathodes are simultaneously actuated to generate a large focal spot / line on the anode for delivering radiotherapy treatment. Figure 4B and Figure 4C Schematic map shows Figure 4A The X-ray source shown according to an aspect of this disclosure includes a field emission cathode (or a group of field emission cathodes) that is selectively actuated (while the remainder is de-actuated) in order to deliver radiation dose to the target. Figure 4B In this method, the electronic current from each field emission cathode or each group of field emission cathodes is modulated to produce intensity-modulated radiotherapy (IMRT) along the large focal spot / line. Figure 5 The schematic diagram illustrates a method for providing multiple operating modes of an X-ray source apparatus according to one aspect of this disclosure; Figure 6A The schematic diagram illustrates an X-ray source arranged according to one aspect of this disclosure in treatment / power mode and actuated to deliver radiotherapy treatment to a target; Figure 6B and Figure 6C Schematic map shows Figure 6A The arrangement of the X-ray source according to this aspect of the present disclosure in treatment / power mode, wherein the X-ray source is configured to achieve a single large focal spot / line on the anode and to emit X-ray radiation guided through a single slit collimator for delivery of radiotherapy treatment to the target. Figure 6B ), and wherein the X-ray source is configured to achieve multiple large focal spots / lines on the anode and to emit X-ray radiation guided through a slit collimator with multiple slits for delivering radiotherapy treatment to the target ( Figure 6C ); Figure 7A and Figure 7B A schematic diagram illustrates an X-ray source arranged in imaging mode according to one aspect of this disclosure, wherein the X-ray source is configured to achieve a small focal spot on the anode and to emit X-ray radiation guided by a cone-beam collimator for imaging a target, as shown in an axial view. Figure 7A ) and from the sagittal view ( Figure 7B As shown in the figure; Figure 8AThe schematic diagram illustrates a radiotherapy system including a multimodal X-ray source according to one aspect of this disclosure; Figure 8B and Figure 8C Schematic map shows Figure 8A The radiotherapy system according to this disclosure shown in the figure includes an X-ray source and an X-ray detector mounted on a gantry, wherein the gantry and / or the patient are movable relative to each other. Figure 8B ), or in which the X-ray source and / or X-ray detector can move relative to each other ( Figure 8C This facilitates the alignment / positioning of the target relative to the X-ray source; Figure 9 The schematic diagram illustrates a method for delivering multimodal X-ray therapy to a target according to one aspect of this disclosure; Figure 10 Schematic map shows Figure 8A The radiotherapy system according to this disclosure shown in the figure has a plurality of X-ray sources and a plurality of corresponding X-ray detectors opposite to the X-ray detectors mounted on a gantry. Figure 11 schematically illustrates a radiotherapy system according to one aspect of the present disclosure, wherein an X-ray source is configured to form both an imaging and a therapeutic focal spot on an anode, and wherein a single collimator having both a cone-beam collimator and a slit collimator is associated with the X-ray source, such that imaging and radiotherapy treatment can be performed simultaneously. Figure 12 (a)- Figure 12 (c) A schematic diagram illustrates a radiotherapy system according to one aspect of the present disclosure, wherein a single slit collimator is implemented for therapeutic and imaging purposes; Figure 13A and Figure 13B Schematic map shows by Figure 12 The radiotherapy system according to this disclosure shown in (a)-12(c) uses a single slit collimator ( Figure 13A Used for original diagnostic images of the target / tumor ( Figure 13B Images of the target / tumor generated through registration; and Figure 14 The schematic diagram illustrates a radiotherapy system according to one aspect of this disclosure, wherein an X-ray source is mounted on a robotic arm. Detailed Implementation

[0054] This disclosure will now be described more fully below with reference to the accompanying drawings, which illustrate some, but not all, embodiments of the disclosure. In fact, these disclosures may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Throughout the text, the same reference numerals refer to the same elements.

[0055] One aspect of this disclosure includes a multimode X-ray source device, which is generally indicated by the number 100 (see, for example...). Figure 2A , Figure 2B In some aspects, such an X-ray source device 100 includes an anode 200 and a field emission cathode device 300 spaced apart from the anode 200, wherein the field emission cathode device 300 is arranged to emit electrons (e.g., an electron beam 305) toward the anode 200.

[0056] On one hand, the field emission cathode device 300 includes a plurality of individually controllable field emission cathodes 310. Therefore, since X-ray imaging typically requires a small focal spot size on the anode 200 to provide higher resolution for imaging, the X-ray source device 100 can operate in an imaging mode for imaging purposes (see, for example, imaging for obtaining a view of the target from an imaging angle). Figure 2A In some configurations of the field emission cathode device 300, only one field emission cathode 310, or several, a few, or other small number of field emission cathodes 310, can be actuated to achieve a relatively small focal spot (e.g., sub-millimeter to several millimeters in diameter) of the electron beam 305 on the anode 200. In some configurations of the X-ray source 100, different individual field emission cathodes 310 (or different several, a few, or other small number of field emission cathodes 310) can be actuated to achieve another view of the target from a different perspective, such as... Figure 2B As shown in the diagram. In imaging mode, the energy of the X-ray source (e.g., energy proportional to the voltage applied to the anode 200) can be adjusted to an appropriate range for imaging (e.g., approximately 30 kV–160 kV) to achieve suitable X-ray imaging results. In some aspects, such as… Figure 3 As shown, for example for three-dimensional (3D) imaging purposes, multiple views of a target can be obtained from various perspectives. That is, as... Figure 3 As shown, a group of one or more field emission cathodes can be sequentially actuated to generate a series of X-ray images from different perspectives. These images can be appropriately processed and combined to reconstruct and achieve a 3D view of the target object.

[0057] In another aspect of this disclosure, the X-ray source 100 can operate in either a treatment mode or a power mode to generate a relatively large focal spot of the electron beam 305 on the anode 200. That is, in some cases, a large number (or all) of multiple field emission cathodes 310 can be simultaneously actuated, wherein the emitted electron beams are directed toward adjacent or overlapping focal spots on the anode 200, such that the spots / regions of the anode 200 affected by the electron beam 305 combine to form a combined large focal spot or focal line (e.g., up to 10 cm) on the anode 200, for example, as shown in the image. Figure 4A As shown in the diagram, the large focal spot / line allows the X-ray source 100 to operate at relatively high power to provide a proportionally high radiation dose rate (e.g., exceeding 40 Gy / sec) as output. For example, for better treatment outcomes, the energy of the X-ray source 100 can be increased by increasing the voltage applied to the anode 200 to a relatively high level (e.g., approximately 160 kV–800 kV) to achieve a suitable radiation dose rate distribution across the target.

[0058] In some respects, the X-ray source 100 in treatment / power mode can selectively actuate only some of the field emission cathodes 310, while the rest of the field emission cathodes 310 remain deactotropic, for example as... Figure 4B As shown in the diagram. Furthermore, the current from each of the actuated field emission cathodes (the electron flow in the electron beam) (and thus the X-ray radiation emitted from the corresponding focal spot on the anode 200) can be programmed / modulated to have different intensity levels, for example, as... Figure 4C As shown. Figure 4C As shown, this selective field emission cathode actuation and electron beam modulation operation mode of the X-ray source 100 causes different radiation intensities from the corresponding focal spot, and thus allows for intensity-modulated radiotherapy (IMRT) capability in SFRT treatment protocols.

[0059] For example, aspects of the multimode X-ray source 100 may involve a field emission cathode device 300 that can switch between an imaging mode and a power mode or a treatment mode. The imaging mode has an emission electron / electron beam 305 focused on a first focal region on an anode 200, wherein the first focal region has a first focal region size, and the power mode or treatment mode has an emission electron / electron beam 305 focused on a second focal region on an anode 200, wherein the second focal region has a second focal region size larger than the first focal region size.

[0060] In one aspect, the field emission cathode device 300 includes a plurality of individually controllable field emission cathodes 310, which are configured and arranged such that an imaging mode includes a first amount of field emission cathodes 310, which are actuated to guide electrons (electron beam 305) emitted by the first amount of field emission cathodes 310 to a first focal region on the anode 200. In a further aspect, the field emission cathode device 300 is configured such that a power mode includes a second amount of field emission cathodes 310, which are actuated to guide electrons (electron beam 310) emitted by the second amount of field emission cathodes 310 to a second focal region on the anode 200. The second amount of field emission cathodes 310 is greater than the first amount of field emission cathodes 310. Furthermore, the second amount of field emission cathodes 310 are arranged to guide electrons (electron beams or currents) emitted by the second amount of field emission cathodes 310 to corresponding focal regions on the anode 200, wherein the corresponding focal regions are disposed adjacently on the anode 200 and are arranged to form a second focal region on the anode 200. In a further aspect, each of the second amount of field emission cathodes 310 is actuated to provide an electron current / electron beam directed towards the anode 200, and wherein the current from one or more selected field emission cathodes 310 of the second amount of field emission cathodes 310 is modulated to modulate the intensity of electrons emitted by the selected one or more field emission cathodes 310 to the second focal region. Therefore, the first amount of field emission cathodes 305 and the second amount of field emission cathodes 305 in the field emission cathode device 300 can be selected and arranged to provide appropriate focal spot sizes on the anode 200 for imaging and treatment / power modes, respectively, wherein the appropriate energy for each mode is determined based on the voltage applied to the anode 200.

[0061] like Figure 5 As shown, another aspect of this disclosure provides a method for providing a multi-mode X-ray source device 100, wherein the X-ray source device 100 includes an anode 200 and a field emission cathode device 300 spaced apart from the anode 200 and arranged to emit electrons toward the anode 200. Such a method includes arranging the field emission cathode device 300 in an imaging mode to focus electrons onto a first focal region on the anode 200, wherein the first focal region has a first focal region size (box 510); and reversibly switching the arrangement of the field emission cathode device 300 to a power mode to focus electrons onto a second focal region on the anode 200, wherein the second focal region has a second focal region size larger than the first focal region size (box 520).

[0062] In some aspects, the field emission cathode device 300 includes a plurality of individually controllable field emission cathodes 310, and the step of arranging the field emission cathode device 300 in an imaging mode includes actuating a first amount of field emission cathodes 310 to guide electrons emitted by the first amount of field emission cathodes 310 to a first focal region on the anode 200. In other aspects, the field emission cathode device 300 includes a plurality of individually controllable field emission cathodes 310, and the step of switching the arrangement of the field emission cathode device 300 to a power mode includes actuating a second amount of field emission cathodes 310 to guide electrons emitted by the second amount of field emission cathodes 310 to a second focal region, wherein the second amount is greater than the first amount. In further other aspects, the step of guiding electrons to the second focal region includes guiding electrons from each of the second amount of field emission cathodes 310 to a corresponding corresponding focal region on the anode 200, wherein the corresponding corresponding focal regions are disposed adjacently on the anode 200 and are arranged to form a second focal region on the anode. In a further aspect, each of the second amount of field emission cathodes 310 emits an electronic current directed toward the anode 310 when it is actuated, and the method includes modulating the electronic current emitted by one or more selected field emission cathodes 310 of the second amount of field emission cathodes 310 in order to modulate the intensity of the electrons or electronic current emitted by the selected one or more field emission cathodes 310 to the second focal region on the anode 200.

[0063] Therefore, aspects of the multi-mode X-ray source 100 disclosed herein include the ability to reversibly switch the same X-ray source between imaging mode and treatment / power mode by programming the control of the field emission cathode device 300, allowing selective actuation of one or more of the plurality of field emission cathodes 310 of the field emission cathode device 300. This selective actuation capability of the field emission cathodes 310 of the field emission cathode device 300 can be implemented in many different ways, such as those disclosed in co-pending U.S. Patent Application No. 18 / 247,265 entitled “Multi-Beam X-ray Source and Method for Forming Same”, assigned to NCX Corporation, which is incorporated herein by reference. For example, for multi-mode operation of the X-ray source 100, multiple individually addressable and actuable field emission cathodes can be implemented. In this way, dual modes can be configured so that the size of the electron beam focal spot on the anode 200 can be appropriately varied, so that a small focal spot is used for imaging mode, while a large focal spot is used for radiotherapy treatment in treatment / power mode.

[0064] For example, Figure 6AAs shown, an X-ray source 100 configured to achieve a large focal spot on the anode of an X-ray source 100 for radiotherapy treatment is used in a treatment / power mode. In some aspects, the large focal spot size can be cumulative, as one or more electron beams can be directed to a single focal spot / line on the anode, or one or more electron beams can be directed to multiple focal spots / lines on the anode, where multiple focal spots / lines cumulatively provide a large focal spot for the X-ray source 100 in treatment / power mode. In treatment mode, a relatively high radiation dose rate is generally preferred for patient treatment (e.g., a tumor as the "target"). The large focal spot / line achieved via the X-ray source in treatment mode allows the X-ray source 100 to operate at relatively high power (higher anode voltage, higher electron current, and longer exposure time / duty cycle). A slit collimator 600 is used to generate spatially discrete X-ray beams required for SFRT treatment (e.g., to extend the radiation dose to the edge of the tumor / target). Although Figures 6A-6C The diagram illustrates a detector 700 opposite to the X-ray source 100, with a target / tumor 750 positioned between them. However, in practice, when the X-ray source 100 is in treatment / power mode, the detector 700 is optional and can be repositioned or removed. In addition to the X-ray source 100 being arranged and configured in treatment / power mode such that an electron current is directed to a single focal spot / line or multiple focal spots / lines on the anode, the slit collimator 600 for guiding the X-ray beam(s) emitted by the X-ray source 100 can also be configured to have a single slit opening (see, for example...). Figure 6B ) or multiple slit openings (see example) Figure 6C If the X-ray beams emitted by one or more of the slit collimators 600 are not sufficiently extended to irradiate the tumor 750, the X-ray source 100 and / or the patient may be translated / moved during the treatment procedure (see example). Figure 6B This allows one or more X-ray beams to irradiate the entire tumor. Alternatively, the radiotherapy treatment can be divided into several sub-treatments, each covering a portion of the target / tumor 750. That is, in such a case, the X-ray source 100 can be positioned and actuated to deliver a first radiation dose to a first portion of the target / tumor 750. The de-actuated X-ray source 100 is then moved / translated and then positioned and actuated to deliver a second radiation dose to a second portion of the target / tumor 750, and this process is repeated to provide radiotherapy treatment to the entire target / tumor 750.

[0065] For example, Figure 7A and Figure 7BAs shown, the X-ray source 100, configured to achieve a small focal spot on the anode, is used to image the target / tumor 750 using the X-ray source in imaging mode. A smaller focal spot on the anode is more suitable for imaging purposes because it provides higher spatial resolution for imaging. Additionally, in imaging mode, the X-ray source 100 can operate at relatively low power (e.g., lower anode voltage, lower electron current, and shorter exposure time / duty cycle), allowing the anode to withstand the power requirements associated with a smaller focal spot. In some aspects, the cone-beam collimator 625 is used to guide one or more X-ray beams emitted by the X-ray source 100 to define the field size for imaging, as detected by the detector 700.

[0066] In some respects, the multimode X-ray source 100 can be integrated into the patient treatment system 400, for example... Figure 8A As shown in the diagram. Such a system 400 may include a gantry 410 for supporting an X-ray source 100 relative to an X-ray detector 700. An examination table / worktable 420 is positioned adjacent to the gantry 410 for supporting a patient, such that a target / tumor 750 is positioned between the X-ray source 100 and the X-ray detector 700. The examination table / worktable 420 may be laterally movable (e.g., movable in a horizontal plane) to translate the patient into alignment with one or more therapeutic X-ray beams and / or imaging X-ray beams emitted by the X-ray source 100. Figure 8B As shown, the gantry 410 can be configured to rotate about a central axis extending through the gantry 410 and parallel to the examination table / worktable 420, such that the X-ray source 100 / X-ray detector 700 pair can orbit around the patient to treat the tumor / target from different directions and / or image the tumor / target. In some cases, such as Figure 8C As shown, the gantry 410 can be configured to allow the X-ray source 100 and / or the X-ray detector 700 to move perpendicular to the central axis (e.g., shift perpendicular to or laterally to the central axis). That is, Figure 8C The schematic diagram illustrates that the X-ray source 100 and / or X-ray detector 700 can be mounted on a guide rail 710, allowing their respective distances from the central axis to be adjusted. This adjustable distance provides flexibility for achieving optimal treatment and / or imaging setup. For example, a relatively large distance between the X-ray source 100 and the central axis (e.g., the imaging center) will provide a larger radiation field (e.g., a larger X-ray beam) for treatment and imaging. In another example, a relatively small distance between the X-ray source 100 and the central axis / imaging center will increase the radiation dose rate used for treatment and imaging.

[0067] The computer workstation / controller 430 communicates with the examination table / workbench 420, the gantry 410, the X-ray source 100, and the X-ray detector 700 to manage, for example, radiotherapy planning and radiotherapy delivery and control. Such functions include, for example, aligning and moving the patient via the examination table / workbench 420 and / or the gantry 410; switching the X-ray source 100 between imaging and treatment / power modes; moving the X-ray detector 700 independently of the X-ray source 100 (e.g., moving the X-ray detector 700 away when the X-ray source 100 is in treatment / power mode); moving the X-ray detector 700 independently of or in conjunction with moving the X-ray source 100 (e.g., shifting the X-ray source 100 and / or the X-ray detector 700 perpendicular to or laterally to the central axis); controlling the X-ray source 100 and the X-ray detector 700 as needed in both imaging and treatment / power modes; and processing the X-ray beam detected by the X-ray detector 700 to form the desired image of the target 750. In certain aspects, the X-ray source 100 can be controlled by the controller 430, enabling the X-ray source 100 and thus the system 400 to seamlessly switch between treatment / power mode and imaging mode to provide real-time image-guided radiotherapy (IGRT). In some aspects, those skilled in the art will understand that the switching of the system 400 between treatment / power mode and imaging mode also includes the switching of collimators, for example, switching between a cone-beam collimator (imaging) and a slit collimator (treatment / power).

[0068] In Figure 8AIn one example of the workflow associated with the treatment system 400 shown, a SFRT treatment plan is first generated using a workstation / controller 430 based on necessary system 400 and patient information. Once the treatment plan is completed, it is stored in the workstation / controller 430 and / or transmitted to the system 400 for treatment delivery and control. Before starting SFRT treatment, the patient is positioned on the examination table / workbench 420 according to the treatment plan and the configuration of the system 400. A set of X-ray images is then acquired while the X-ray source 100 operates in imaging mode (small focal spot of the electron beam on the anode) to facilitate patient setup (e.g., to determine the spatial location and width of the target / tumor relative to the X-ray source 100). Once the patient is properly positioned and aligned, the X-ray source 100 is switched to the treatment / power mode (large focal spot / line of the electron beam(s) on the anode) for SFRT treatment. During SFRT treatment, the operation of system 400 in treatment / power mode of X-ray source 100 can be paused, and X-ray source 100 can switch to imaging mode to confirm patient placement (e.g., the target to be treated, reference markers, etc.). If the patient / target placement does not correspond to the placement on which the treatment plan is formed, the patient / target is re-aligned and placed before X-ray source 100 switches back to treatment / power mode to continue SFRT treatment.

[0069] exist Figure 9The schematic diagram illustrates one aspect of this disclosure, which includes a method of providing multimodal X-ray therapy to a target 750 within an object (e.g., a patient) using an X-ray apparatus comprising an X-ray source 100 and an X-ray detector 700, wherein the X-ray source 100 includes an anode 200 and a field emission cathode device 310, the field emission cathode device 310 being spaced apart from the anode 200 and arranged to emit electrons 305 toward the anode 200, and wherein the target 750 is determined based on diagnostic imaging of the object and the diagnostic image of the target 750 is obtained through diagnostic imaging of the object. Such a method includes: arranging the field emission cathode device 310 of the X-ray source 100 in an imaging mode to focus electrons 305 onto a first focal region on the anode 200, the first focal region having a first focal region size (box 910); arranging the field emission cathode device 300 of the X-ray source 100 in an imaging mode to focus electrons 305 onto a first focal region on the anode 200, the first focal region having a first focal region size (box 920); and imaging the target 750 by actuating the X-ray source 100 in the imaging mode to emit an imaging X-ray beam toward the X-ray detector 700, such that the imaging X-ray beam interacts with the target 750 to obtain a first X-ray image of the target 750. (Box 930); In response to a comparison of a first X-ray image of target 750 and a diagnostic image of target 750, adjust X-ray source 100 or object to register target 750 with the diagnostic image of target 750 and to guide X-ray source 100 toward target 750 (Box 940); Switch the arrangement of field emission cathode device 300 to power mode to focus electrons 305 onto a second focal region on anode 200, the second focal region having a second focal region size larger than the first focal region size (Box 950); And in power mode, actuate X-ray source 100 to emit a first therapeutic X-ray beam toward target 750 to deliver a first X-ray dose to target 750.

[0070] In some aspects, such methods include: after delivering a first X-ray dose to a target 750, switching the arrangement of the field emission cathode device 300 of the X-ray source 100 to an imaging mode; re-imaging the target 750 using the X-ray device to obtain a second X-ray image of the target 750; adjusting the X-ray source 100 or the object in response to a comparison of the second X-ray image of the target 750 and a diagnostic image of the target 750 for registering the target 750 with the diagnostic image of the target 750, and for guiding the X-ray source 100 toward the target 750; switching the arrangement of the field emission cathode device 300 to a power mode to focus electrons 305 onto a second focal region on the anode 200; and actuating the X-ray source 100 in a power mode to emit a second therapeutic X-ray beam toward the target 750 to deliver a second X-ray dose to the target 750.

[0071] In some aspects, the method includes arranging an X-ray detector 700 opposite to the X-ray source 100 when the field emission cathode device 300 of the X-ray source 100 is in transmission imaging mode. In other aspects, the method includes arranging the X-ray detector 700 adjacent to the X-ray source 100 when the field emission cathode device 300 of the X-ray source 100 is in backscatter imaging mode. In such cases, backscattering elements (not shown) may be provided and positioned opposite the X-ray source 100 such that an object / target is positioned between them, wherein the backscattering elements are configured / arranged to reflect one or more imaging X-rays back toward the X-ray detector 700 positioned toward the adjacent X-ray source 100.

[0072] In some aspects, the method includes: when the field emission cathode device 300 of the X-ray source 100 is in power mode, arranging the X-ray detector 700 to not receive the first therapeutic X-ray beam or the second therapeutic X-ray beam. In other aspects, adjusting the X-ray source 100 or the object includes adjusting the distance between the X-ray source 100 and the object, adjusting the angular position of the X-ray source 100 in a trajectory around the object, and / or adjusting the position of the X-ray source 100 or the object lateral to the other and not parallel to the imaging X-ray beam.

[0073] In some aspects, the edges (e.g., boundaries) of the target 750 are determined based on diagnostic imaging. In such aspects, the method includes collimating a first or second therapeutic X-ray beam emitted by the X-ray source 100 in power mode such that the lateral dimensions of the respective first and second therapeutic X-ray beams are not greater than the lateral dimensions of the target 750 perpendicular to the edges of the respective first and second therapeutic X-ray beams (i.e., a collimator can be implemented to optimize the therapeutic X-ray beam to the size of the target 750 in order to minimize irradiation of healthy tissue surrounding the target 750). In other aspects, the step of collimating the first or second therapeutic X-ray beam includes using a slit collimator 600 to collimate the first or second therapeutic X-ray beam emitted by the X-ray source 100 in power mode such that the first or second therapeutic X-ray is emitted onto the target 750 as a linear region. In other aspects, the step of using a cone-beam collimator 625 to collimate the first or second imaging X-ray beam emitted by the X-ray source 100 in imaging mode causes the first or second imaging X-ray to be emitted onto the object as an elliptical or circular region. As disclosed herein, the steps of performing imaging and re-imaging of the target and delivering the first and second X-ray doses are performed using the same X-ray source 100.

[0074] In some cases, the step of actuating the X-ray source 100 in power mode to deliver a first X-ray dose or a second X-ray dose to the target 750 includes: actuating the X-ray source 100 in power mode to deliver the first X-ray dose or the second X-ray dose to the target 750 at a predetermined X-ray dose rate for a predetermined time, thereby providing a cumulative X-ray dose to the target 750. In other cases, the method includes: tracking the movement of the object during the delivery of the first X-ray dose; and in response to the tracked movement of the object (i.e., any movement of the object can be tracked via a reference marker attached to the object such that it maintains a known spatial relationship with the target 750, regardless of the movement of the object), adjusting the X-ray source 100 or the object to register the target 750 with a diagnostic image of the target 750, and to maintain the X-ray source 100 pointing towards the target 750.

[0075] To perform such methods, aspects of this disclosure include a corresponding multimode X-ray system 400 for providing X-ray therapy to a target 750 within an object, the target 750 being determined based on diagnostic imaging of the object, and the diagnostic image of the target 750 being obtained through diagnostic imaging of the object. The X-ray system 400 includes: an X-ray detector 700; an X-ray source 100 including an anode 200 and a field emission cathode device 300 spaced apart from the anode 200 and arranged to emit electrons 305 toward the anode 200; and a controller 430 communicating with the X-ray source 100 and the X-ray detector 700. The controller 430 is configured to: guide the X-ray source 100 to arrange the field emission cathode device 300 in an imaging mode, thereby focusing electrons 305 onto a first focal region on the anode 200, wherein the first focal region has a first focal region size; image the target 750 by actuating the X-ray source 100 in the imaging mode to emit an imaging X-ray beam, such that the imaging X-ray beam interacts with the target 750 and is detected by the X-ray detector 700 to obtain a first X-ray image of the target 750; and, in response to the first X-ray image of the target 750 and a diagnostic image of the target 750... The comparison involves adjusting the X-ray source 100 or the object to register the target 750 with a diagnostic image of the target 750, and guiding the X-ray source 100 toward the target 750; guiding the X-ray source 100 to switch the arrangement of the field emission cathode device 300 to a power mode, thereby focusing electrons 305 onto a second focal region on the anode 200, wherein the second focal region has a second focal region size larger than the first focal region size; and actuating the X-ray source 100 in power mode to emit a first therapeutic X-ray beam toward the target 750 to deliver a first X-ray dose to the target 750.

[0076] In some aspects, the controller 430 is configured to: after a first X-ray dose is delivered to the target 750, guide the X-ray source 100 to switch the arrangement of the field emission cathode device 300 to an imaging mode; re-image the target 750 using the X-ray device to obtain a second X-ray image of the target 750; adjust the X-ray source 100 or the object to register the target 750 with the diagnostic image of the target 750 in response to a comparison of the second X-ray image of the target 750 and a diagnostic image of the target 750, and guide the X-ray source 100 toward the target 750; guide the X-ray source 100 to switch the arrangement of the field emission cathode device 300 to a power mode, thereby focusing electrons 305 onto a second focal region on the anode 200; and actuate the X-ray source 100 in a power mode to emit a second therapeutic X-ray beam toward the target 750 to deliver a second X-ray dose to the target 750.

[0077] In some aspects, when the field emission cathode device 300 of the X-ray source 100 is in transmission imaging mode, the X-ray detector 700 is arranged opposite to the X-ray source 100; in other aspects, when the field emission cathode device 300 of the X-ray source 100 is in backscatter imaging mode, the X-ray detector 700 is arranged adjacent to the X-ray source 100. In some aspects, when the field emission cathode device 300 of the X-ray source 100 is in power mode (e.g., when the X-ray detector 700 is de-actuated or otherwise removed from the effective path of one or more X-ray beams emitted by the X-ray source 100), the X-ray detector 700 is arranged not to receive the first therapeutic X-ray beam or the second therapeutic X-ray beam.

[0078] In some respects, the controller 430 is configured to adjust the X-ray source 100 or the object by adjusting the distance between the X-ray source 100 and the object, adjusting the angular position of the X-ray source 100 in the orbit around the object, or adjusting the position of the X-ray source 100 or the object relative to the other and not parallel to the imaging X-ray beam.

[0079] In some aspects, the edge of the target 750 is determined based on diagnostic imaging, and the system 400 includes a collimator disposed between the X-ray source 100 and the object, wherein the collimator is configured to collimate a first therapeutic X-ray beam or a second therapeutic X-ray beam emitted by the X-ray source 100 in power mode such that the lateral dimension of the respective first therapeutic X-ray beam and the second therapeutic X-ray beam is not greater than the lateral dimension of the target 750 perpendicular to the edge of the respective first therapeutic X-ray beam and the second therapeutic X-ray beam. Such a collimator may include a slit-beam collimator 600 configured to collimate the first therapeutic X-ray beam or the second therapeutic X-ray beam emitted by the X-ray source 100 in power mode such that the first therapeutic X-ray beam or the second therapeutic X-ray beam is emitted onto the target 750 as a linear region. In other aspects, such collimators may include a cone-beam collimator 625 disposed between the X-ray source 100 and the object, and configured to collimate a first or second imaging X-ray beam emitted by the X-ray source 100 in imaging mode, such that the first or second imaging X-ray beam is emitted onto the object as an elliptical or circular region. In some aspects, imaging and re-imaging of the target 750, as well as delivery of the first and second X-ray doses, are performed using the same X-ray source 100.

[0080] In some aspects, controller 430 is configured to actuate X-ray source 100 in power mode to deliver a first or second X-ray dose to target 750 at a predetermined X-ray dose rate for a predetermined time, thereby providing a cumulative X-ray dose to target 750. In other aspects, a tracking device (e.g., a reference marker detectable by the X-ray device in imaging mode, or a reference marker and detector system communicating with controller 430) is included to communicate with controller 430 and is configured to track the movement of the object during the delivery of the first X-ray dose, wherein controller 430 is configured to adjust X-ray source 100 or the object in response to the tracked movement of the object for registering target 750 with a diagnostic image of target 750, and for maintaining X-ray source 100 pointed at target 750.

[0081] Benefiting from the teachings presented in the foregoing description and associated drawings, those skilled in the art to which the disclosures to which this document pertain will conceive of numerous modifications and other embodiments of these disclosures. For example, instead of a single X-ray source 100 / single X-ray detector 700 pair mounted to the gantry 410, some aspects of this disclosure may include a plurality of X-ray sources 100 and corresponding X-ray detectors 700 mounted on the gantry 410, such as... Figure 10As shown in the diagram. Such an arrangement can, for example, deliver multiple radiotherapy treatments to the target / tumor 750 from different directions / angles to achieve a high dose rate in a shorter treatment time. Imaging of the target 750 can also be performed from different directions / angles and / or the target 750 can be imaged by one X-ray source 100 / X-ray detector 700 while (e.g., simultaneously) a second X-ray source 100 delivers radiotherapy treatment to the target / tumor 750.

[0082] In another example, the X-ray source 100 can be configured to simultaneously generate both therapeutic and imaging X-ray beams, such as... Figure 11A and Figure 11B As shown in the diagram. More specifically, in one example, the X-ray source 100 can be configured / programmed to cause certain field emission cathodes 310 of the field emission cathode device 300 to form two small focal spots on the anode 200 for imaging purposes, wherein these two small focal spots are located on opposite sides of three large focal spots / lines formed by actuating other groups of field emission cathodes for radiotherapy purposes. Such a configuration can allow the radiotherapy treatment X-ray beam and the imaging X-ray beam to be independently collimated with a single fixed collimator assembly 650 (e.g., including a cone-beam collimator 625 and a slit collimator 600 in a single assembly, and arranged to minimize the overlap between the imaging X-ray beam and the treatment X-ray beam). The imaging X-ray beam can be actuated during treatment (e.g., when (one or more) radiotherapy treatment X-ray beams are actuated) to provide real-time imaging guidance and feedback without interrupting radiotherapy. Two corresponding X-ray detectors 705 can also be mounted to the gantry 410 and used to capture the imaging X-ray beam to provide imaging guidance and feedback during treatment.

[0083] In yet another example, the slit collimator 600 can also be implemented for imaging purposes during radiotherapy treatment. For example... Figure 12 As shown in (a), a single-slit collimator 600 (which may have one or more slits) is used for both treatment and imaging. During the radiotherapy procedure, the X-ray source 100 can be configured and arranged such that a group of field emission cathodes 310 is actuated to form a large focal spot / line, wherein the large focal spot / line is aligned with the slit defined by the collimator 600 for generating the treatment X-ray beam, as... Figure 12 As shown in (b). Between sub-treatments of the target / tumor 750, the field emission cathode device 300 can be switched to imaging mode, such that one or a small group of field emission cathodes 310 are actuated to form small focal spots on the anode 200. Figure 12As shown in (c), in imaging mode, a small focal spot is advantageous for high-resolution imaging capture. The pattern of the small focal spot is selected to match the pattern of the slit in the slit collimator 600. In such cases, due to interference from the portion defining the slit of the slit collimator 600 (e.g., the strip of the slit collimator), the imaging X-ray beam guided through the slit of the slit collimator 600 and detected by the X-ray detector 700 will result in the generation of an incomplete / partial image of the target 750, as shown in (c). Figure 13A As shown in the image, a partial image including a portion of the target / tumor 750 can still be registered to the original diagnostic image of the target / tumor 750 (see, for example...). Figure 13B And therefore, it can still provide imaging guidance and feedback during radiotherapy treatment.

[0084] In yet another example, such as Figure 14 As shown, for optimal interaction with the target / tumor 750, the X-ray source 100 can be mounted on the robotic arm 1000 instead of a gantry, allowing greater flexibility and degrees of freedom of movement when positioning the X-ray source 100 in three-dimensional (3D) space. In such a configuration, a corresponding X-ray detector can be mounted to another robotic arm (not shown) to provide imaging guidance and feedback during radiotherapy and / or as the X-ray source 100 moves via the movement of the robotic arm 1000. In other cases, the corresponding X-ray detector can also be mounted adjacent to the X-ray source 100 on the same robotic arm 1000, where the X-ray source 100 can be configured to utilize backscattering modes for X-ray imaging, imaging guidance, and feedback purposes.

[0085] Therefore, it should be understood that this disclosure is not limited to the specific embodiments disclosed, and modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terminology is used herein, it is used in a general and descriptive sense only and not for limiting purposes.

Claims

1. A method for providing multimodal X-ray therapy to a target within an object using an X-ray apparatus, the X-ray apparatus comprising an X-ray source and an X-ray detector, the X-ray source comprising an anode and a field emission cathode device, the field emission cathode device being spaced apart from the anode and arranged to emit electrons toward the anode, and the target being determined based on diagnostic imaging of the object and the diagnostic image of the target being obtained through diagnostic imaging of the object, the method comprising: The field emission cathode device of the X-ray source is arranged in an imaging mode to focus the electrons onto a first focal region on the anode, the first focal region having a first focal region size; The target is imaged by actuating the X-ray source in the imaging mode to emit an imaging X-ray beam toward the X-ray detector, such that the imaging X-ray beam interacts with the target to obtain a first X-ray image of the target; In response to a comparison of the first X-ray image of the target and the diagnostic image of the target, the X-ray source or the object is adjusted to register the target with the diagnostic image of the target and to guide the X-ray source toward the target; The arrangement of the field emission cathode device is switched to a success rate mode to focus the electrons onto a second focal region on the anode, the second focal region having a larger size than the first focal region; as well as In the power mode, the X-ray source is actuated to emit a first therapeutic X-ray beam toward the target to deliver a first X-ray dose to the target.

2. The method of claim 1, comprising: After the first X-ray dose is delivered to the target, the arrangement of the field emission cathode device of the X-ray source is switched to the imaging mode; The target is re-imaged using the X-ray equipment to obtain a second X-ray image of the target; In response to a comparison of the second X-ray image of the target and the diagnostic image of the target, the X-ray source or the object is adjusted to register the target with the diagnostic image of the target and to guide the X-ray source toward the target; The arrangement of the field emission cathode device is switched to the power mode to focus the electrons onto the second focal region on the anode; as well as In the power mode, the X-ray source is actuated to emit a second therapeutic X-ray beam toward the target to deliver a second X-ray dose to the target.

3. The method of claim 1, comprising: When the field emission cathode device of the X-ray source is in transmission imaging mode, the X-ray detector is arranged opposite to the X-ray source.

4. The method of claim 1, comprising: When the field emission cathode device of the X-ray source is in backscatter imaging mode, the X-ray detector is arranged adjacent to the X-ray source.

5. The method of claim 2, comprising: When the field emission cathode device of the X-ray source is in the power mode, the X-ray detector is arranged not to receive the first therapeutic X-ray beam or the second therapeutic X-ray beam.

6. The method of claim 2, wherein, Adjusting the X-ray source or the object includes adjusting the distance between the X-ray source and the object, adjusting the angular position of the X-ray source in its orbit around the object, or adjusting the position of the X-ray source or the object relative to another and not parallel to the imaging X-ray beam.

7. The method of claim 2, wherein, The edge of the target is determined based on the diagnostic imaging, and the method includes: collimating the first therapeutic X-ray beam or the second therapeutic X-ray beam emitted by the X-ray source in the power mode such that the lateral dimension of the respective first therapeutic X-ray beam and the second therapeutic X-ray beam is not greater than the lateral dimension of the target perpendicular to the edge of the respective first therapeutic X-ray beam and the second therapeutic X-ray beam.

8. The method of claim 7, wherein, Collimating the first therapeutic X-ray beam or the second therapeutic X-ray beam includes: using a slit collimator to collimate the first therapeutic X-ray beam or the second therapeutic X-ray beam emitted by the X-ray source in the power mode, such that the first therapeutic X-ray beam or the second therapeutic X-ray beam is emitted onto the target as a linear region.

9. The method of claim 2, wherein, Actuating the X-ray source in the power mode to deliver a first X-ray dose or a second X-ray dose to the target includes: actuating the X-ray source in the power mode to deliver a first X-ray dose or a second X-ray dose to the target at a predetermined X-ray dose rate for a predetermined time, thereby providing a cumulative X-ray dose to the target.

10. The method of claim 2, comprising performing imaging and re-imaging of the target using the same X-ray source and delivering the first X-ray dose and the second X-ray dose.

11. The method of claim 2, further comprising using a cone beam collimator to collimate the first imaging X-ray beam or the second imaging X-ray beam emitted by the X-ray source in the imaging mode, such that the first imaging X-ray beam or the second imaging X-ray beam is emitted onto the object as an elliptical or circular region.

12. The method of claim 1, comprising: The movement of the object is tracked during the delivery of the first X-ray dose; as well as In response to the tracked movement of the object, the X-ray source or the object is adjusted to register the target with the diagnostic image of the target and to maintain the X-ray source pointing towards the target.

13. A multimodal X-ray system for delivering X-ray therapy to a target within an object, the target being determined based on diagnostic imaging of the object and the diagnostic image of the target being obtained through diagnostic imaging of the object, the X-ray system comprising: X-ray detector; An X-ray source comprising an anode and a field emission cathode, the field emission cathode being spaced apart from the anode and arranged to emit electrons toward the anode; as well as A controller, which communicates with the X-ray source and the X-ray detector, is configured to: The X-ray source is guided to arrange the field emission cathode device in an imaging mode, thereby focusing the electrons onto a first focal region on the anode, the first focal region having a first focal region size; By actuating the X-ray source to emit an imaging X-ray beam in the imaging mode, the target is imaged such that the imaging X-ray beam interacts with the target and is detected by the X-ray detector to obtain a first X-ray image of the target; In response to a comparison of the first X-ray image of the target and the diagnostic image of the target, the X-ray source or the object is adjusted to register the target with the diagnostic image of the target, and the X-ray source is directed toward the target; The X-ray source is guided to switch the arrangement of the field emission cathode device to a success mode, thereby focusing the electrons onto a second focal region on the anode, the second focal region having a second focal region size larger than the first focal region; as well as In the power mode, the X-ray source is actuated to emit a first therapeutic X-ray beam toward the target to deliver a first X-ray dose to the target.

14. The system of claim 13, wherein, The controller is configured to: After the first X-ray dose is delivered to the target, the X-ray source is guided to switch the arrangement of the field emission cathode device to the imaging mode; The target is re-imaged using the X-ray equipment to obtain a second X-ray image of the target; In response to a comparison of the second X-ray image of the target and the diagnostic image of the target, the X-ray source or the object is adjusted to register the target with the diagnostic image of the target, and the X-ray source is directed toward the target; The X-ray source is guided to switch the arrangement of the field emission cathode device to a power mode, thereby focusing the electrons onto the second focal region on the anode; as well as In the power mode, the X-ray source is actuated to emit a second therapeutic X-ray beam toward the target to deliver a second X-ray dose to the target.

15. The system of claim 13, wherein, When the field emission cathode device of the X-ray source is in transmission imaging mode, the X-ray detector is arranged opposite to the X-ray source.

16. The system of claim 13, wherein, When the field emission cathode device of the X-ray source is in backscatter imaging mode, the X-ray detector is arranged adjacent to the X-ray source.

17. The system of claim 14, wherein, When the field emission cathode device of the X-ray source is in the power mode, the X-ray detector is arranged not to receive the first therapeutic X-ray beam or the second therapeutic X-ray beam.

18. The system of claim 14, wherein, The controller is configured to adjust the X-ray source or the object by: adjusting the distance between the X-ray source and the object, adjusting the angular position of the X-ray source in an orbit around the object, or adjusting the position of the X-ray source or the object relative to the other and not parallel to the imaging X-ray beam.

19. The system of claim 14, wherein, The edge of the target is determined based on the diagnostic imaging, and wherein the system includes a collimator disposed between the X-ray source and the target, the collimator being configured to collimate the first therapeutic X-ray beam or the second therapeutic X-ray beam emitted by the X-ray source in the power mode such that the lateral dimension of the respective first therapeutic X-ray beam and the second therapeutic X-ray beam is not greater than the lateral dimension of the target perpendicular to the edge of the respective first therapeutic X-ray beam and the second therapeutic X-ray beam.

20. The system of claim 19, wherein, The collimator includes a slit beam collimator configured to collimate the first therapeutic X-ray beam or the second therapeutic X-ray beam emitted by the X-ray source in the power mode, such that the first therapeutic X-ray beam or the second therapeutic X-ray beam is emitted onto the target as a linear region.

21. The system of claim 14, wherein, The controller is configured to actuate the X-ray source in the power mode to deliver a first X-ray dose or a second X-ray dose to the target at a predetermined X-ray dose rate for a predetermined time, thereby providing a cumulative X-ray dose to the target.

22. The system of claim 14, wherein, Imaging and re-imaging the target, as well as delivering the first and second X-ray doses, are performed using the same X-ray source.

23. The system of claim 14, further comprising a cone-beam collimator disposed between the X-ray source and the object, and configured to collimate the first imaging X-ray beam or the second imaging X-ray beam emitted by the X-ray source in the imaging mode, such that the first imaging X-ray beam or the second imaging X-ray beam is emitted onto the object as an elliptical or circular region.

24. The system of claim 13, comprising a tracking device in communication with the controller and configured to track movement of the subject during delivery of the first X-ray dose, wherein, The controller is configured to adjust the X-ray source or the object in response to tracked movement of the object, for registering the target with the diagnostic image of the target, and for maintaining the X-ray source pointing at the target.

25. A method of providing a multi-mode X-ray source apparatus, the X-ray source apparatus comprising an anode and a field emission cathode, the field emission cathode being spaced apart from the anode and arranged to emit electrons toward the anode, the method comprising: The field emission cathode device is arranged in an imaging mode to focus the electrons onto a first focal region on the anode, the first focal region having a first focal region size; as well as The arrangement of the field emission cathode device is reversibly switched to a success rate mode to focus the electrons onto a second focal region on the anode, the second focal region having a second focal region size larger than the first focal region.

26. The method of claim 25, wherein, The field emission cathode device includes a plurality of individually controllable field emission cathodes, and wherein arranging the field emission cathode device in the imaging mode includes actuating a first amount of field emission cathodes to guide electrons emitted by the first amount of field emission cathodes to the first focal region on the anode.

27. The method of claim 26, wherein, The field emission cathode device includes a plurality of individually controllable field emission cathodes, and wherein switching the arrangement of the field emission cathode device to the power mode includes actuating a second amount of field emission cathodes to guide electrons emitted by the second amount of field emission cathodes to a second focal region, the second amount being greater than the first amount.

28. The method of claim 27, wherein, Guiding the electrons to the second focal region includes guiding the electrons from each of the second amount of field emission cathodes to a corresponding corresponding focal region on the anode, the corresponding corresponding focal regions being arranged adjacently and configured to form the second focal region on the anode.

29. The method of claim 28, wherein, Each of the second amount of field emission cathodes emits an electron current directed toward the anode when it is actuated, and wherein the method includes modulating the current emitted by one or more selected field emission cathodes of the second amount of field emission cathodes in order to modulate the intensity of electrons emitted by the one or more selected field emission cathodes to the second focal region.

30. A multi-mode X-ray source device, comprising: anode; as well as A field emission cathode device, spaced apart from and arranged to emit electrons toward the anode, the field emission cathode device being switchable between an imaging mode and a power mode, the imaging mode focusing the electrons onto a first focal region on the anode having a first focal region size, and the power mode focusing the electrons onto a second focal region on the anode having a second focal region size larger than the first focal region size.

31. The device as claimed in claim 30, wherein, The field emission cathode device includes a plurality of individually controllable field emission cathodes, which are configured such that the imaging mode includes a first amount of field emission cathodes, which are actuated to guide electrons emitted by the first amount of field emission cathodes to the first focal region on the anode.

32. The device as claimed in claim 31, wherein, The field emission cathode device is configured such that the power mode includes a second amount of field emission cathode, the second amount being greater than the first amount, the second amount of the field emission cathode being actuated to guide electrons emitted by the second amount of the field emission cathode to the second focal region.

33. The device as claimed in claim 32, wherein, The second amount of field emission cathodes are arranged to guide electrons emitted by the second amount of field emission cathodes to a corresponding focal region on the anode, the corresponding focal regions being arranged adjacently and to form the second focal region on the anode.

34. The device as claimed in claim 33, wherein, Each of the second amount of field emission cathodes emits an electron current directed toward the anode when it is actuated, and wherein the electron current emitted by one or more selected field emission cathodes of the second amount of field emission cathodes can be modulated to modulate the intensity of electrons emitted by the one or more selected field emission cathodes to the second focal region.

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