Quality assurance for dose supply in radiation therapy

Abstract

Embodiments of the present disclosure relate to quality assurance for dose delivery in radiotherapy. A computer-implemented method of determining doses delivered by a radiation therapy system to a plurality of locations within a region of a patient's anatomy includes: placing the radiation therapy system in a first machine state during a first time period of a treatment fraction; delivering radiation to a region of the patient's anatomy during the first time period; generating a first surface map of the region of the patient anatomy based on the surface measurements acquired during the first time period; generating a first modified digital volume of the region based on the first surface map; and for each of the plurality of locations within the region of the patient anatomy, determining a first radiation dose delivered to the location during the first time period, where the first radiation dose is based on a first machine state of the radiation therapy system and the first modified digital volume.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] The subject matter of this application is related to U.S. patent application "Treatment Adaptation in Radiotherapy Based on Intra-Fraction Dosing", which was filed on August 28, 2023, and has a serial number of 18 / 239,110. The subject matter of this related application is hereby incorporated by reference into this article. Technical Field

[0003] The present invention relates to a computer-implemented method for determining the dose delivered by a radiation therapy system to multiple locations within a region of a patient's anatomical structure, a computer-implemented method for radiation therapy of multiple locations within a region of a patient's anatomical structure and a corresponding computer-readable storage medium, as well as a computer system. Background Art

[0004] Unless otherwise indicated herein, the approaches described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.

[0005] Radiation therapy is a localized treatment of a specific target tissue (planning target volume), such as a cancerous tumor. Ideally, radiation therapy is performed on the planning target volume, which prevents surrounding normal tissue from receiving a dose exceeding a specified tolerance, thereby minimizing the risk of damage to healthy tissue. Prior to radiation therapy, an imaging system is typically used to provide a three-dimensional image of the target tissue and surrounding area, called a "treatment planning image." Based on this imaging, the size and mass of the target tissue can be estimated, the planning target volume can be determined, and an appropriate treatment plan can be generated.

[0006] In order to correctly deliver the prescribed dose to the planned target volume (i.e., target tissue) during radiotherapy, immediately prior to a radiotherapy session (or fraction), the patient is correctly positioned relative to the linear accelerator that delivers the radiotherapy. Typically, dosimetry data and geometric data are checked before and during treatment fractions so the patient is correctly positioned and the radiotherapy treatment administered matches the previously planned treatment. This process is known as image-guided radiation therapy (IGRT) and involves using an imaging system to observe the target tissue prior to, and in some cases during, delivery of radiation to the planned target volume. Prior to delivering radiation, IGRT uses imaging coordinates from the treatment plan to ensure that the patient is properly aligned in the radiotherapy device for treatment. Typically, the target tissue is observed using a reconstructed region of the patient's anatomy, which is generated based on an X-ray image of the region that was acquired immediately prior to the radiotherapy session. Summary of the invention

[0007] According to various embodiments, for each of a plurality of time periods constituting a single radiation therapy fraction, an actual dose delivered by a radiation therapy system to a location within a region of a patient's anatomy is calculated. The novel dose calculation is based on a time-resolved machine state of the radiation therapy system for each time period and a time-resolved patient surface captured at each time period of the treatment fraction. The total dose delivered to each location within the region of the patient's anatomy can then be determined based on the delivered dose calculated for each of the time periods.

[0008] In some embodiments, a computer-implemented method for determining a dose delivered by a radiation therapy system to multiple locations within a region of a patient's anatomy includes: placing the radiation therapy system in a first time-resolved machine state during a first time period of a treatment fraction; delivering radiation to a region of the patient's anatomy during the first time period; generating a first surface map for the region of the patient's anatomy based on surface measurements acquired during the first time period; generating a first modified digital volume of the region based on the first surface map; and determining, for each of a plurality of locations within the region of the patient's anatomy, a first radiation dose delivered to the location during the first time period, wherein the first radiation dose is based on the first time-resolved machine state of the radiation therapy system and the first modified digital volume.

[0009] In some embodiments, a computer-implemented method for radiotherapy of multiple locations within a region of an anatomical structure of a patient includes: determining a first total radiation dose delivered to a first location included in a plurality of locations during a first treatment fraction, wherein the first radiation dose is based on a first time-resolved machine state of the radiotherapy system associated with the first treatment fraction and a time-resolved surface map of the region associated with the first treatment fraction; determining a dose error associated with the first location for the first treatment fraction based on the first total radiation dose; determining a second total radiation dose to be delivered to the first location in a second treatment fraction based on the dose error; changing a time-resolved machine state of the radiotherapy system associated with the second treatment fraction from an original time-resolved machine state to a modified time-resolved machine state based on the second total radiation dose; and delivering the second total radiation dose to the first location using the modified time-resolved machine state.

[0010] Further embodiments include a non-transitory computer-readable storage medium including instructions for causing a computer system to perform one or more of the above methods, and a computer system configured to perform one or more of the above methods.

[0011] The foregoing summary is illustrative only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The above and other features of the present disclosure will become more apparent from the following description and the appended claims in conjunction with the accompanying drawings. These drawings depict only a few embodiments according to the present disclosure and are therefore not to be considered as limiting the scope thereof. The present disclosure will be described with additional specificity and detail through the use of the accompanying drawings.

[0013] Figure 1 is a perspective view of a radiation therapy system in which various aspects of the present disclosure may be advantageously implemented.

[0014] Figure 2 Schematically shows a Figure 1 Drive brackets and racks for radiotherapy systems.

[0015] Figure 3 Schematically shows a Figure 1 Drive brackets and racks for radiotherapy systems.

[0016] Figure 4 Schematically illustrates a method based on various embodiments Figure 1 A radiation therapy system includes a digital volume constructed by generating projection images from one or more X-ray images.

[0017] Figure 5 A flow chart of a computer-implemented method for determining radiation dose delivered by a radiation therapy system to a plurality of locations within a region of a patient's anatomy is set forth in accordance with one or more embodiments.

[0018] Fig. 6A , Figure 6B , Figure 6C , Fig.6D , Fig. 6E and Fig. 6F It shows the various embodiments Figure 5 The various steps of the computer-implemented method.

[0019] Figure 7 A flow chart is set forth for a computer-implemented method 700 for radiation therapy of a region of a patient anatomy in accordance with one or more embodiments.

[0020] Figure 8 A flow chart is set forth for a computer-implemented method 800 for radiation therapy of a region of a patient anatomy in accordance with one or more embodiments.

[0021] Fig. 9 is an illustration of a computing device configured to perform various embodiments.

[0022] Fig.10 is a block diagram of an illustrative embodiment of a computer program product for implementing one or more embodiments. DETAILED DESCRIPTION

[0023] In the following detailed description, reference is made to the accompanying drawings which form a part hereof. In the drawings, similar symbols generally identify similar components unless the context dictates otherwise. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented herein. It will be readily understood that the various aspects of the present disclosure as generally described herein and shown in the drawings may be arranged, substituted, combined, and designed in a variety of different configurations, all of which are expressly contemplated and form a part of the present disclosure.

[0024] introduce

[0025] As previously mentioned, image-guided radiation therapy (IGRT) is often used to facilitate the correct delivery of the prescribed dose to the planned target volume. In IGRT, patient motion and / or changes in the shape or position of the planned target volume may be an important factor in the efficacy of radiation therapy, and steps are therefore taken to minimize or monitor patient motion. For example, patients are often fixed via prefabricated molds, masks or other positioning hardware to reduce motion. In addition, in some cases, the movement caused by the patient's breathing is controlled or constrained by breath-holding techniques, spirometers, belts, etc. However, even when such motion reduction measures are adopted, changes in the shape or position of the patient's motion and / or the planned target volume may also occur during treatment fractions. At present, it is difficult to consider the impact of such motion and / or anatomical changes on the total dose accumulation in the planned target volume or organs at risk (OARs) using traditional techniques. For example, the current daily quality assurance (QA) method for dose delivery is usually based on the system log file of the radiotherapy period to reconstruct the delivered dose, which accurately indicates the position of the delivered dose relative to the isocenter of the system of the delivered dose. This method can ensure that the planned dose is delivered as expected relative to the system isocenter. However, if the patient moves between the start and end of treatment, the effect of such movement on the dose to the target or healthy tissue is not recorded.

[0026] In view of the foregoing, there is a need in the art for improved techniques for tracking the actual dose delivered during radiation therapy.

[0027] According to various embodiments, for each of the multiple time periods that make up a single radiotherapy period (or fractionation), the actual dose delivered by the radiotherapy system to the position within the region of the patient's anatomical structure is calculated. The novel dose calculation is based on the time-resolved machine state of each time period of the radiotherapy system and the time-resolved patient surface captured in each time period of the treatment fractionation. The total dose delivered to each position within the region of the patient's anatomical structure can then be determined based on the delivered dose calculated for each time period in the time period. In some embodiments, the novel dose calculation contributes to dose supply quality assurance (QA), wherein the subsequently planned treatment fractionation is changed to compensate for the substandard dose supply during the completed treatment fractionation. In some embodiments, the novel dose calculation facilitates adaptive treatment during a specific treatment fractionation. In such embodiments, the planned treatment fractionation can be dynamically changed to compensate for the substandard dose supply that occurred earlier in the specific treatment fractionation. Various example embodiments are described below.

[0028] System Overview

[0029] Figure 1 1 is a perspective view of a radiation therapy system 100 in which various embodiments can be advantageously implemented. In some embodiments, the radiation therapy (RT) system 100 includes an imaging system configured to image the patient's anatomical structure using X-ray imaging technology. For example, in some embodiments, the RT system 100 is configured to provide stereotactic radiosurgery and precision radiation therapy for lesions, tumors, and conditions at any part of the body where radiation therapy is indicated. Therefore, the RT system 100 may include one or more of the following: a linear accelerator (LINAC) that generates a megavolt (MV) treatment beam of high-energy X-rays, one or more kilovolt (kV) X-ray sources, one or more X-ray imagers, and in some embodiments, an MV electronic portal imaging device (EPID). For example, the radiation therapy system 100 is described herein as being configured with a circular gantry. In other embodiments, the radiation therapy system 100 may be configured with a C-shaped gantry that can be infinitely rotated via a slip ring connection. In other embodiments, any imaging system capable of generating a two-dimensional (2D) projection X-ray image, such as as part of a cone beam computed tomography (CBCT) process, can advantageously implement the various embodiments described herein. In another example of such an embodiment, the radiation therapy system 100 can be configured with an imaging system having MRI-based imaging capabilities.

[0030] Typically, the RT system 100 is capable of kV imaging of a target volume immediately before or during application of an MV treatment beam, so that an IGRT and / or intensity modulated radiation therapy (IMRT) procedure can be performed using X-ray imaging. The RT system 100 may include one or more touch screens 101, a bed motion controller 102, an aperture 103, a base positioning assembly 105, a bed 107 disposed on the base positioning assembly 105, and an image acquisition and treatment control computer 106, all of which are disposed within a treatment room. The RT system 100 also includes a remote control console 110, which is disposed outside the treatment room and enables treatment delivery and patient monitoring from a remote location. The base positioning assembly 105 is configured to accurately position the bed 107 relative to the aperture 103, and the motion controller 102 includes an input device, such as a button and / or switch, that enables a user to operate the base positioning assembly 104 to automatically and accurately position the bed 107 to a predetermined position relative to the aperture 103. The motion controller 102 also enables a user to manually position the bed 107 to a predetermined position.

[0031] In some embodiments, the RT system 100 further includes one or more patient monitoring sensors 109. The patient monitoring sensors 109 may be incorporated into a patient position monitoring system or a surface image guidance system (not shown) that may generate a surface map of the surface of the patient positioned on the bed 107. In some embodiments, the patient monitoring sensors 109 may include a stereo vision camera, a time-of-flight sensor, a surface scanner, etc., for calculating a real-time 3D mesh of the surface of the patient positioned on the bed 107. Thus, the patient position monitoring system or surface image guidance system including the patient monitoring sensors 109 may be used for setting up the patient and / or patient positioning accessories, inter-fraction positioning, and intra-fraction patient motion management. For example, in some cases, when the position of the patient on the bed 107 during treatment exceeds a predefined excursion threshold, the treatment beam may be automatically turned off. In some embodiments, the patient position monitoring or surface image guidance system including the patient monitoring sensors 109 is incorporated into the RT system 100. In other embodiments, the patient position monitoring or surface image guidance system may be a system that is external to the RT system 100 but communicatively coupled to the RT system.

[0032] According to various embodiments, a patient position monitoring or surface image guidance system including a patient monitoring sensor 109 is used to generate a surface map of the patient multiple times during a radiation therapy treatment fractionation. Thus, in such embodiments, the patient monitoring sensor 109 is used to generate a time-resolved surface of the patient's anatomy that can aid in determining the radiation dose delivered by the RT system 100 to multiple locations within a region of the patient's anatomy. Such embodiments are described in more detail below.

[0033] Figure 2 The drive bracket 200 and the frame 210 of the RT system 100 according to various embodiments are schematically shown. Figure 2 The cover, base positioning assembly 105, bed 107 and other components of the RT system 100 are omitted. The drive support 200 is a fixed support structure for the components of the RT treatment system 110, and the drive support 200 includes a gantry 210 and a drive system 201 for rotatably moving the gantry 210. The drive support 200 rests on a support surface outside the RT treatment system 110 and / or is fixed to the support surface, such as the floor of the RT treatment facility. The gantry 210 is rotatably coupled to the drive support 200, and the gantry 210 is a support structure on which various components of the RT system 100 are mounted, including a linear accelerator (LINAC) 204, an MV electronic portal imaging device (EPID) 205, an imaging X-ray source 206, and an X-ray imager 207. During operation of the RT treatment system 110, the gantry 220 rotates around the hole 103 when actuated by the drive system 201.

[0034] The drive system 201 rotationally actuates the gantry 210. In some embodiments, the drive system 201 includes a linear motor that can be fixed to the drive support 200 and interact with a magnetic track (not shown) mounted on the gantry 210. In other embodiments, the drive system 201 includes another suitable drive mechanism for precisely rotating the gantry 210 about the bore 201. The LINAC 204 generates an MV treatment beam 230 of high energy X-rays (or in some embodiments, electrons, protons and / or other heavy charged particles, ultra-high dose rate X-rays (e.g., for FLASH radiotherapy), or microbeams for microbeam radiotherapy), and the EPID 205 is configured to acquire X-ray images with the treatment beam 230. The imaging X-ray source 206 is configured to direct a cone-shaped X-ray beam (referred to herein as imaging X-rays 231) through the isocenter 203 of the RT system 100 to the X-ray imager 207, and the isocenter 203 generally corresponds to the location of the target volume 209 to be treated. In Figure 2 In the illustrated embodiment, the X-ray imager 207 is depicted as a planar device, while in other embodiments the X-ray imager 207 may have a curved configuration.

[0035] The X-ray imager 207 receives the imaging X-rays 231 and generates a suitable projection image therefrom. According to certain embodiments, such projection images may then be employed to construct or update a portion of the imaging data for a digital volume corresponding to a three-dimensional (3D) region including the target volume 209. That is, a 3D image of such a 3D region is reconstructed based on the projection image. In some embodiments, CBCT and / or digital tomosynthesis (DTS) may be used to process the projection images generated by the X-ray imager 207. CBCT is typically used to acquire projection images over a relatively long acquisition arc, such as over a 180° or greater rotation of the gantry 210. As a result, a high-quality 3D reconstruction of the imaging volume may be generated. CBCT is typically used to generate a 3D reconstruction of the setup at the beginning of a radiotherapy period. For example, CBCT may be employed immediately before applying the treatment beam 230 to generate a 3D reconstruction that confirms that the target volume 209 has not moved or changed shape.

[0036] exist Figure 2 In the illustrated embodiment, the RT system 100 includes a single X-ray imager and a single corresponding imaging X-ray source. In other embodiments, the RT system 100 may include two or more X-ray imagers, each with a corresponding imaging X-ray source. Figure 3 One such embodiment is shown in .

[0037] Figure 3 The drive support 300 and the gantry 310 of the RT system 100 according to various embodiments are schematically shown. The drive support 300 and the gantry 310 are similar in configuration to the RT system 100 except that the components of the RT system 100 mounted on the gantry 310 include the first imaging X-ray source 306, the first X-ray imager 307, the second imaging X-ray source 308, and the second X-ray imager 309. Figure 2 309. The drive support 200 and the gantry 200 in are substantially similar. In such embodiments, including multiple X-ray imagers in the RT system 100 facilitates generating projection images (for reconstructing the target volume) over a shorter image acquisition arc. For example, in some cases, when the RT system 100 includes two X-ray imagers and corresponding X-ray sources, sufficient information can be collected to reconstruct a 3D region including the target volume 309 without rotating the gantry 310. Alternatively, in some cases, when the RT system 100 includes two X-ray imagers and corresponding X-ray sources, the image acquisition arc for acquiring projection images of a particular image quality can be approximately half of the image acquisition arc for acquiring projection images of similar image quality using a single X-ray imager and X-ray source.

[0038] Depend on Figure 2 The X-ray imager 207 (or Figure 3The projection images generated by the first X-ray imager 307 and the second X-ray imager 309 in the image processing apparatus are used to reconstruct a 3D digital volume of an object or a portion of the patient's anatomy, such as a 3D region of the patient's anatomy including the target volume 209. Figure 4 An embodiment of such a digital volume is described below.

[0039] Figure 4 The digital volume 400 constructed based on projection images generated by one or more X-ray imagers included in the RT system 100 according to various embodiments is schematically shown. For example, in some embodiments, the projection images may be generated by a single X-ray imager (such as the X-ray imager 207), and in other embodiments the projection images may be generated by multiple X-ray imagers (such as the first X-ray imager 307 and the second X-ray imager 309).

[0040] The digital volume 400 includes a plurality of voxels 401 (dashed lines) of anatomical image data, wherein each voxel 401 corresponds to a different location within the digital volume 400. For clarity, Figure 4 Only a single voxel 401 is shown in FIG. The digital volume 400 corresponds to a 3D region including a target volume 410. Figure 4 In FIG. 4 , the digital volume 400 is depicted as an 8x8x8 voxel cube, but in practice, the digital volume 400 typically includes many more voxels, such as Figure 4 The multiple orders of magnitude shown in .

[0041] For the purposes of discussion, the target volume 410 may refer to the gross tumor volume (GTV), clinical target volume (CTV), or planning target volume (PTV) for a particular treatment. The GTV depicts the location and extent of the gross tumor, such as what can be seen or imaged; the CTV includes the GTV and an additional margin for subclinical disease spread, which is generally not imageable; and the PTV is a geometric concept designed to ensure that the appropriate radiation therapy dose is actually delivered to the CTV without adversely affecting nearby organs at risk. Therefore, the PTV is typically larger than the CTV, but in some cases, it may also be reduced in some parts to provide a safety margin around organs at risk. The PTV is typically determined based on imaging performed prior to treatment time, and alignment of the PTV with the current position of the patient's anatomy at the time of treatment is facilitated by X-ray imaging of the digital volume 400.

[0042] In some embodiments, the image information associated with each voxel 401 of the digital volume 400 is constructed via projection images generated by a single or multiple X-ray imagers via a CBCT process. For example, such a CBCT process can be employed immediately before the treatment beam 230 is delivered to the target volume 410, so that the position and shape of the target volume 410 can be confirmed before treatment begins.

[0043] Time-resolved surface dose calculation based on time-resolved machine states and patient anatomy

[0044] According to various embodiments, the radiation dose delivered by a radiotherapy system to a location within a digital volume, such as digital volume 400, is calculated based on a time-resolved machine state and a time-resolved surface of a patient's anatomy. More specifically, a treatment fraction is divided into multiple time periods, e.g., having a duration on the order of a few milliseconds. For each time period, a change in the position and / or shape of the target volume 400 (and, in some embodiments, the OAR) relative to a planned isocenter can be inferred from the time-resolved surface of the patient's anatomy for that time period. In this way, for each time period of a treatment fraction, the effect of such a change in position and / or shape on the radiation dose delivered to each location within the digital volume can be calculated and tracked. The following is in conjunction with Figures 5 to 6F One such embodiment is described below.

[0045] Figure 5 A flow chart of a computer-implemented method 500 for determining radiation dose delivered by a radiation therapy system to a plurality of locations within a region of a patient's anatomy is set forth in accordance with one or more embodiments. Fig. 6A , Figure 6B , Figure 6C , Fig.6D , Fig. 6E and Fig. 6F Schematically illustrated are various steps of the computer-implemented method 500. In some embodiments, the computer-implemented method 500 may be performed as a radiotherapy session or radiotherapy treatment fraction. Typically, radiotherapy treatment fractions are used to reduce toxic effects on healthy cells by dividing the total radiation dose of the patient into multiple smaller doses (fractions). Typically, each treatment fraction is delivered over a period of several days or many days, such as daily over several weeks.

[0046] The computer-implemented method 500 may include one or more operations, functions, or actions, as shown in one or more of blocks 501-520. Although the blocks are shown in a sequential order, the blocks may be performed in parallel and / or in a different order than described herein. In addition, various blocks may be combined into fewer blocks, divided into additional blocks, and / or eliminated based on the desired implementation. Although the RT system 100 and Figures 1 to 4 A computer-implemented method 500 is described, but those skilled in the art will appreciate that it is within the scope of the present embodiments to perform the computer-implemented method 500 via any appropriately configured radiation therapy system. For example, in some embodiments, some or all of the operations associated with the computer-implemented method 500 may be performed via Figure 1 The computer-implemented method 500 may be implemented in the image acquisition and treatment control computer 106 and / or the remote control console 110 in the RT system 100. Alternatively or in addition, in some embodiments, some or all of the operations associated with the computer-implemented method 500 may be implemented via one or more computing devices external to the RT system 100. In such embodiments, one or more of the operations associated with the computer-implemented method 500 may be performed offline, such as after completing a radiation therapy fraction and before starting a subsequent radiation therapy treatment fraction.

[0047] In step 501, a patient is positioned within the RT system 100 for a radiation therapy treatment fraction, which may be one of a plurality of treatment fractions planned for the patient. In some embodiments, the patient 601 is positioned on the couch 107 such that the isocenter 203 of the RT system 100 is included in a region of interest 602 of the patient's anatomy, such as Fig. 6A In some embodiments, tattoos or other skin markings are used to facilitate positioning of the patient 601 relative to the RT system 100. A region of interest 602 of the patient's anatomy, hereinafter referred to as "region 602," may be any technically feasible portion of the patient's anatomy, such as the head, chest, abdomen, etc., that includes the PTV or other target volume 209. As shown, region 602 includes a surface 603 of the patient 601. For clarity, the region 602 is not shown in FIG. Fig. 6A In the illustrated embodiment, region 602 is depicted as a 2D cross-section of patient 601. In practice, region 602 is typically a 3D region of the patient's anatomy. Fig. 6A In the illustrated embodiment, surface 603 is depicted as a 2D contour of patient 601 , whereas in practice surface 603 is typically a 3D surface of some or all of patient 601 .

[0048] In step 502, pre-processing imaging is performed on region 602. In some embodiments, X-ray imaging of region 602 is performed in step 602, such as via an onboard imaging system included in RT system 100. In such embodiments, CBCT X-ray images are acquired using imaging X-ray source 206 and X-ray imager 207 or by a computed tomography (CT) imaging system coupled to or associated with RT system 100. In other embodiments, in step 502, magnetic resonance imaging (MRI) is performed, such as via an MRI system coupled to or associated with RT system 100.

[0049] In step 503, a pre-processed digital volume 612 of the region 602 is reconstructed based on the imaging performed in step 502. The pre-processed digital volume 612 of the region 602 is typically Figure 4 The digital volume 400 in the embodiment is consistent with the 3D digital volume and includes the target volume 209, such as Figure 6B As shown. Figure 6B In the illustrated embodiment, the pre-processed digital volume 612 is depicted relative to the couch 107 and the isocenter 203. Because the pre-processed digital volume 612 is reconstructed based on the imaging performed in step 502, the pre-processed digital volume 612 indicates the current position of the target volume 209 and the surface 603 relative to the isocenter 203 and components of the RT system 100, such as the gantry 210 and the LINAC 204.

[0050] In step 504, a baseline digital volume 622 of the region 602 is generated based on the imaging performed in step 502. In some embodiments, the baseline digital volume 622 of the region 602 is generated by deformably registering the planning digital volume 632 (dashed line) of the region 602 to the pre-processed digital volume 612 of the region 602, such as Figure 6CAs shown. Typically, a planning digital volume 632 of the region 602, such as a planning CT image or a CT-quality CBCT image, is acquired prior to the computer-implemented method 500. Alternatively, in some embodiments, the planning digital volume 632 of the region 602 is acquired during the computer-implemented method 500, for example via mounted CT-quality CBCT imaging. Deformable image registration accounts for or tracks soft tissue deformations between image acquisitions, and is the process of finding correspondences between elements of a first 2D image or 3D volume of the region 602 (e.g., the planning digital volume 632) and elements of a subsequently acquired second 2D image or 3D volume (e.g., the pre-processed digital volume 612). As is well known in the art, deformable image registration is designed to find such correspondences that are not the result of a simple rigid shift and / or rotation of the region 602 between acquisitions. A variety of different algorithms have been developed for deformable image registration in radiotherapy applications, including optical and fluid flow, spline-based methods, and biomechanical models. Any suitable deformable registration algorithm may be employed in step 504.

[0051] exist Figure 6C In the illustrated embodiment, the baseline digital volume 622 accurately indicates the current position of the target volume 209 and the planned isocenter 609 (cross-hatched) relative to the current isocenter 203 of the RT system 100. Therefore, in step 505, the current position of the planned isocenter 609 relative to the current isocenter 203 of the RT system 100 can be determined via the baseline digital volume 622.

[0052] In step 506, the position of the treatment couch 107 is changed so that the position of the region 602 is shifted relative to the current isocenter 203 of the RT system 100, such as Fig.6D Specifically, the couch 107 is repositioned to align the planned isocenter 609 with the current isocenter 203 of the RT system 100. Ideally, the planned isocenter 609 is located at the isocenter 203 of the RT system 100 during radiation delivery to facilitate accurate dose delivery of the target volume 209 and to minimize or otherwise reduce the effects of OARs ( Fig.6D The dosage is not shown in FIG. Fig.6D In the illustrated embodiment, the couch 107 is repositioned via vertical shift 605 and horizontal shift 606 to align the planned isocenter 609 with the current isocenter 203. In some embodiments, axial shifts (not shown) into or out of the page may also be employed to align the planned isocenter 609 with the current isocenter 203.

[0053] In step 507, with the planned isocenter 609 aligned with the isocenter 203 of the RT system 100, the radiation therapy treatment fraction associated with the computer-implemented method 500 begins. According to various embodiments, the radiation therapy treatment fraction associated with the computer-implemented method 500 is divided into a plurality of time periods, and steps 510-516 are performed for each time period. In an embodiment, the incremental radiation dose for each time period is determined based on the time period-specific machine state of the RT system 100 and the time period-specific surface of the region 602. Therefore, in this embodiment, the total radiation dose can be determined based on the time-resolved machine state of the RT system 100 and the time-resolved surface of the region 602. Because each time period has a relatively short duration (e.g., on the order of a few milliseconds to tens of milliseconds), the radiation dose determined for each time period has a high level of temporal granularity, and therefore the effect of intra-fraction patient motion on the radiation dose that occurs during a single radiation therapy treatment fraction can be accurately quantified.

[0054] In some embodiments, for each process parameter associated with the RT system 100, the time-resolved machine state of the RT system 100 includes a set of values ​​for a radiotherapy treatment fractionation associated with the computer-implemented method 500. In this embodiment, the set of values ​​for a specific process parameter includes a specific process parameter for each time period of a radiotherapy treatment fractionation. In addition, in this embodiment, the process parameter can be any setting or configuration of the RT system 100 that affects the position and / or intensity of radiation delivery within the region 602 during the radiotherapy treatment fractionation, such as gantry rotation, collimator position, beam energy, etc. Similarly, in some embodiments, the time-resolved surface of the region 602 of the radiotherapy treatment fractionation includes a set of surface maps of the patient's anatomical structure. In this embodiment, each surface map of the set of surface maps of the patient's anatomical structure is generated for different time periods of the radiotherapy treatment fractionation, as described below.

[0055] In step 510, the radiation therapy treatment fraction associated with the computer-implemented method 500 is incremented to the next time period. In step 511, radiation therapy for the current time period of the radiation therapy treatment fraction is performed. Thus, radiation is delivered to the target volume 209 while the RT system 100 is configured in a particular machine state. For example, in some embodiments, the machine state includes the current value of each process parameter associated with the RT system 100 that affects the location and intensity of radiation delivery within the region 602 during the current time period. Thus, in some embodiments, the machine state includes information indicating the current position or setting of each machine axis associated with the RT system 100, such as for the bed 107, the gantry 210, one or more collimators associated with the LINAC 204, the individual leaf positions of the multi-leaf collimator associated with the LINAC 204, the power and / or other operating settings of the LINAC 204 and / or the treatment beam 230. Thus, the machine state of the RT system 100 provides a snapshot of what the RT system 100 is doing during the current time period of the radiation therapy treatment fraction. In general, the specific process parameters to which the machine states refer may vary depending on the specific configuration of the RT system 100, ie, they are system dependent.

[0056] In step 512, the machine state of the RT system 100 during the current time period is stored. For example, in some embodiments, the system log file is updated to include the value of each process parameter associated with the RT system 100 during the current time period.

[0057] In step 513, a surface map of the patient's anatomy is generated for the current time period of the radiation therapy treatment fraction. In some embodiments, a surface map indicating the current surface 613 of the patient 601 relative to the isocenter 203 of the RT system 100 is generated, such as Fig. 6E As shown. Fig. 6E In the illustrated embodiment, the current surface 613 is depicted as a 2D contour of the region 602, but in practice the current surface 613 is typically a 3D surface. In some embodiments, the current surface 613 is generated for a surface associated with the region 602 of the patient's anatomy. In other embodiments, the current surface 613 is generated for a surface associated with most or all of the anatomy of the patient 601. In either case, the surface map of the current surface 613 is generated based on surface measurements acquired during the current time period of the radiation therapy treatment fractionation, such as via one or more patient monitoring sensors 109 and an associated patient position monitoring system or surface image guidance system.

[0058] exist Fig. 6EIn the example of FIG. 6 , intra-fractionation motion of some or all portions of the anatomical structures associated with region 602 causes the current surface 613 to deviate from the surface 623 of the baseline digital volume 622. Such intra-fractionation motion may be caused by voluntary movement of the patient, such as breathing, coughing, skeletal muscle contraction, etc. In addition, such intra-fractionation motion may be caused by involuntary movement, such as organs affected by peristalsis, gas movement, etc. In addition to the deviation of the current surface 613 from the surface 623 of the baseline digital volume 622, the intra-fractionation motion also causes the anatomical structures within region 602 to be displaced from their assumed positions. For example, the intra-fractionation motion may cause the position 607 or shape of the target volume 209 and / or one or more OARs (not shown) within region 602 to change, which directly affects the dose delivered thereto. Therefore, during the current time period, the target volume 209 may receive less dose than planned, and healthy tissue close to the target volume 209 may receive more dose than expected.

[0059] In step 514, a modified digital volume 642 of the region 602 is generated in conjunction with the deformation of the region 602 indicated by the current surface 613. In some embodiments, the modified digital volume 642 is generated by deformably registering the surface 623 of the baseline digital volume 622 to the current surface 613, such as Fig. 6F 602. Note that the surface 623 of the baseline digital volume 622 corresponds to the surface of the patient 601 when the pre-processing imaging of the region 602 was performed in step 502. Alternatively, in some embodiments, the modified digital volume 642 is generated by deformably registering the body contour of the patient 601 to the current surface 613. In this embodiment, the body contour of the patient 601 is based on the imaging acquired via the pre-processing imaging of the region 602 in step 502. In either case, the actual position of the target volume 209, OARs, bone structures, and other anatomical structures within the region 602 relative to the isocenter 203 is indicated by the modified digital volume 642. As a result, the actual incremental dose delivered to the target volume 209 and the OARs and other locations within the region 602 can be determined for the current time period. Any suitable deformable registration algorithm can be employed in step 514.

[0060] Note that the dose delivered to a particular anatomical structure may be significantly affected by changes in the position of that particular anatomical structure relative to the planned position of the anatomical structure. For example, intra-fraction motion during a particular time period may cause the target volume 209 to be displaced from the isocenter 203 and, therefore, receive a dose different from that planned. Similarly, the dose delivered to a particular anatomical structure may be significantly affected by changes in the position of other anatomical structures, such as high radiation density structures that may block a larger portion of the treatment beam 230. For example, intra-fraction motion during a particular time period may cause a bone structure to be accidentally positioned between the target volume 209 and the LINAC 204, thereby reducing the planned dose to the target volume 209 during that particular time period.

[0061] In step 515, an incremental radiation dose is determined for each location within the region 602. In some embodiments, the incremental radiation dose for each location within the region 602 is determined based on the modified digital volume 642 of the region 602 and the machine state of the RT system 100 for the current time period. In this embodiment, the incremental radiation dose for each voxel 401 within the modified digital volume 642 may be determined. Because the modified digital volume 642 indicates the actual location of the target volume 209, OARs, bone structures, and other anatomical structures within the region 602 relative to the isocenter 203, the incremental radiation dose for each voxel 401 within the modified digital volume 642 accurately reflects the radiation dose delivered to such locations within the region 602.

[0062] In step 515, any technically feasible algorithm may be employed to determine the incremental radiation dose for each location within region 602. Various algorithms are known in the art for calculating the 3D delivered dose in a region of the patient's anatomy based on the digital volume of the region and the values ​​of various treatment parameters. Thus, any such algorithm may be employed in step 515. In some embodiments, such an algorithm may be implemented via the image acquisition and treatment control computer 106 and / or the remote control console 110. In other embodiments, a computing device external to the RT system 100 may implement such an algorithm in step 515.

[0063] In step 516 , it is determined whether the radiation therapy treatment fraction is complete. If not, the computer-implemented method 500 returns to step 510 and increments to the next time period of the radiation therapy treatment fraction; if yes, the computer-implemented method 500 proceeds to step 520 .

[0064] In step 520, for each location within the region 602, a total radiation dose delivered during the radiotherapy treatment fraction is determined, wherein the total radiation dose is based on the sum of the incremental radiation doses calculated in each iteration of step 515. As described above, each iteration of step 515 is associated with a different time period of the radiotherapy treatment fraction. In some embodiments, the total radiation dose for a particular location is determined by accumulating the incremental radiation dose for each time period in the planning digital volume 632 for the particular location. However, the incremental dose for each time period is determined based on a specific modified digital volume 642 for the time period, and the specific modified digital volume 642 may reflect changes in the shape of the anatomical structure in the region 602 caused by intra-fraction motion. Therefore, in this embodiment, in order to accumulate the incremental dose associated with a particular time period in the planning digital volume 632, the modified digital volume 642 associated with the particular time period is deformably registered to the planning digital volume 634. In this way, multiple incremental radiation doses received by modified digital volumes 642 of different shapes can be accurately accumulated in the reference digital volume for quality assurance analysis. As described above, the planning digital volume 632 may be a conventional CT image, a CT-quality CBCT image, or the like.

[0065] In the above described embodiments, steps 514 and 515 are performed during each time period of a radiation therapy treatment fraction. In other embodiments, steps 514 and 515 are performed after a radiation therapy treatment fraction has been completed.

[0066] Using time-resolved radiation dosimetry for quality assurance

[0067] In view of the foregoing, the time-resolved (or incremental) radiation dose delivered to locations within the digital volume can be used to accurately determine the total radiation dose delivered in a radiotherapy treatment fraction for each location within the digital volume. Because the incremental radiation dose is calculated based on the time-resolved machine state and the time-resolved surface of the patient's anatomy, the effect of intra-fraction motion on the radiation dose delivered to each location within the digital volume can be considered when calculating the delivered dose. According to various embodiments, based on a dose error detected after a radiotherapy treatment fraction, one or more subsequent radiotherapy treatment fractions are modified to compensate for the detected dose error. The following is combined with Figure 7 One such embodiment will be described.

[0068] Figure 7 A flow chart of a computer-implemented method 700 for radiation therapy of a region of a patient's anatomy is set forth in accordance with one or more embodiments. In some embodiments, the computer-implemented method 700 can be performed as a radiation therapy procedure comprising a plurality of radiation therapy treatment fractions. Typically, each treatment fraction is delivered over a period of several days or many days, such as daily over several weeks.

[0069] The computer-implemented method 700 may include one or more operations, functions, or actions, as shown in one or more of blocks 701-720. Although the blocks are shown in a sequential order, the blocks may be performed in parallel and / or in a different order than described herein. In addition, various blocks may be combined into fewer blocks, divided into additional blocks, and / or eliminated based on the desired implementation. Although the RT system 100 and Figures 1 to 4 A computer-implemented method 700 is described, but those skilled in the art will appreciate that it is within the scope of the present embodiments to perform the computer-implemented method 700 via any appropriately configured radiation therapy system. For example, in some embodiments, some or all of the operations associated with the computer-implemented method 700 may be performed via Figure 1 The image acquisition and treatment control computer 106 and / or the remote control console 110 in the RT system 100 are implemented. Alternatively or additionally, in some embodiments, some or all of the operations associated with the computer-implemented method 700 can be implemented via one or more computing devices external to the RT system 100.

[0070] In step 701, a radiation therapy treatment procedure including a plurality of radiation therapy treatment fractions is started. In some embodiments, the radiation therapy treatment procedure is planned based on a planning CT or other imaging. In some embodiments, for the radiation therapy treatment procedure, there is a target minimum dose to be delivered to the target volume 209 and a maximum allowable dose to one or more OARs or other anatomical structures. Additionally or alternatively, in some embodiments, for each radiation therapy treatment fraction, there is a target minimum dose to be delivered to the target volume 209 and a maximum allowable dose to one or more OARs or other anatomical structures.

[0071] In step 702, the next radiation therapy treatment fraction is started. For example, in some embodiments, the Figure 5 In step 703, while measuring or acquiring the time period-specific surface of region 602, the radiation dose of the current radiotherapy treatment fraction is delivered. For example, in some embodiments, performing the same Figure 5 The operations are consistent with steps 510-513.

[0072] In step 704, the incremental dose delivery for each time period of the current radiation therapy treatment fraction is determined. For example, in some embodiments, the Figure 5 The steps 514 and 515 are performed in accordance with each other. In this embodiment, the incremental dose delivery for the plurality of locations within the region 602 is determined for each time period of the current radiation therapy treatment fraction.

[0073] In step 705, for each location within region 602, a total radiation dose delivered during the radiation therapy treatment fraction is determined, where the total radiation dose is based on the sum of the incremental radiation doses calculated in step 704. For example, in some embodiments, the method described in Figure 5 The same operation as step 520.

[0074] In step 706, determine whether it is necessary to re-plan the remaining radiotherapy treatment fractions. For example, in some embodiments, when the target minimum dose to be delivered for the target volume 209 cannot be achieved by the radiotherapy treatment fractions that have just been completed, it is necessary to re-plan the remaining fractions. Therefore, additional doses will be planned for the target volume 209 to compensate for the detected dose error. In such embodiments, the target minimum dose can indicate the threshold of the radiotherapy treatment fractions that have just been completed or the threshold of all completed radiotherapy treatment fractions (i.e., the operating threshold that increases with each completed radiotherapy treatment fraction). In another example, in some embodiments, when the radiotherapy treatment fractions that have just been completed exceed the maximum allowable dose delivered to one or more OARs, it is necessary to re-plan the remaining fractions. Therefore, less doses are planned in the subsequent radiotherapy treatment fractions of one or more OARs to compensate for the excess dose detected in the earlier radiotherapy treatment fractions. In this embodiment, the maximum allowable dose may indicate the maximum allowable dose value of the radiation therapy treatment fraction that has just been completed or the maximum allowable dose value of all completed radiation therapy treatment fractions (i.e., a running maximum allowable dose value that increases with each completed radiation therapy treatment fraction). If it is determined that the remaining fractions do not need to be replanned, the computer-implemented method 700 proceeds to step 710. If it is determined that the remaining fractions need to be replanned, the computer-implemented method 700 proceeds to step 707.

[0075] In step 707, one or more remaining fractions of the radiation therapy treatment process associated with the computer-implemented method 700 are replanned to compensate for the dose error (or other failure to achieve the dosimetry goal) detected in step 706. In step 707, the total radiation dose for the locations within the region 602 determined in step 705 is replanned. In some embodiments, the replanning of the treatment plan includes changing the time-resolved machine state of the RT system 100 from a previously planned machine state to a new state. In the new state, one or more process parameter values ​​included in the planned machine state are changed. Given the replanned target dose for each location within the region 602, one skilled in the art may employ any suitable treatment planning algorithm to perform step 707. The computer-implemented method 700 then returns to step 702 and performs the next radiation therapy treatment fraction.

[0076] In step 710, it is determined whether there are any remaining radiation therapy treatment fractions to be performed in the radiation therapy procedure associated with the computer-implemented method 700. If so, the computer-implemented method 700 returns to step 702 and performs the next radiation therapy treatment fraction; if not, the computer-implemented method 700 proceeds to step 720 and terminates.

[0077] Applying time-resolved radiation dosing to adaptive radiotherapy

[0078] In some embodiments, the accumulated time-resolved radiation dose delivered to locations within the digital volume can be used to detect dose delivery deviations during a particular radiotherapy treatment fraction. In this embodiment, the radiation dose delivered in the remainder of the radiotherapy treatment fraction can be replanned to compensate for the detected deviation in the dose in the portion of the radiotherapy treatment fraction that has already been performed. As a result, the total radiation dose delivered upon completion of the radiotherapy treatment fraction can be free of dose error or have a reduced dose error. Figure 8 One such embodiment is described below.

[0079] Figure 8 A flow chart of a computer-implemented method 800 for radiation therapy of a region of a patient's anatomy is set forth in accordance with one or more embodiments. In some embodiments, the computer-implemented method 800 may be performed as a radiation therapy treatment fractionation. Typically, a radiation therapy course includes a plurality of such radiation therapy treatment fractionations, wherein each treatment fraction is delivered over a period of several days or many days, such as daily over several weeks.

[0080] The computer-implemented method 800 may include one or more operations, functions, or actions, as shown in one or more of blocks 801-821. Although the blocks are shown in a sequential order, the blocks may be performed in parallel and / or in a different order than described herein. In addition, various blocks may be combined into fewer blocks, divided into additional blocks, and / or eliminated based on the desired implementation. Although the RT system 100 and Figures 1 to 4 A computer-implemented method 800 is described, but those skilled in the art will appreciate that it is within the scope of the present embodiments to perform the computer-implemented method 800 via any appropriately configured radiation therapy system. For example, in some embodiments, some or all of the operations associated with the computer-implemented method 800 may be performed via Figure 1 The image acquisition and treatment control computer 106 and / or the remote control console 110 in the RT system 100 are implemented. Alternatively or additionally, in some embodiments, some or all of the operations associated with the computer-implemented method 800 can be implemented via one or more computing devices external to the RT system 100.

[0081] In step 801, a radiation therapy treatment fraction comprising a plurality of time segments is started. For example, in some embodiments, the radiation therapy treatment fraction is planned based on a planning CT or other imaging and comprises a series of hundreds or thousands of time segments. In some embodiments, for each time segment of the radiation therapy treatment fraction, there is a target minimum dose to be delivered to the target volume 209 and a maximum allowable dose to one or more OARs or other anatomical structures. In some embodiments, the steps performed in step 801 are as follows: Figure 5 In step 802, the radiation therapy treatment fraction associated with the computer-implemented method 800 is incremented to the next time period.

[0082] In step 803, radiation therapy is performed for the current time period of the radiation therapy treatment fraction. Thus, radiation is delivered to the target volume 209 while the RT system 100 is configured in a specific machine state for a specific time period. In some embodiments, the execution of Figure 5 The same operation as step 511.

[0083] In step 804, the time period specific machine state of the RT system 100 in the current time period is stored. In some embodiments, execution with Figure 5 The same operation as step 512.

[0084] In step 805, a surface map of the patient's anatomy is generated for the current time period of the radiation therapy treatment fraction. Figure 5 The same operation as step 513.

[0085] In step 806, a modified digital volume 642 of the region 602 is generated in conjunction with the deformation of the region 602 indicated by the current surface 613. In some embodiments, the process of performing the process in conjunction with Figure 5 The same operation as step 514.

[0086] In step 807, an incremental radiation dose is determined for each location within region 602. In some embodiments, the Figure 5 The same operation as step 515.

[0087] In step 808, for each location within region 602, a total radiation dose delivered during the radiation therapy treatment fraction is determined, wherein the total radiation dose is based on the sum of the incremental radiation doses calculated in each iteration of step 807. In some embodiments, the method of performing the above steps is performed in conjunction with Figure 5 The same operation as step 520.

[0088] In step 810, it is determined whether there are any remaining sessions to be performed in the radiation therapy treatment fractionation. If so, the computer-implemented method 800 proceeds to step 820; if not, the computer-implemented method 800 proceeds to step 830 and terminates.

[0089] In step 820, it is determined whether the radiation doses at all locations within region 602 are within specified limits and that the remainder of the radiation therapy treatment fractions do not need to be replanned. In some embodiments, the same procedure as in step 821 is performed. Figure 7 If it is determined that the radiation doses for all locations within the region 602 are within the specified limits, the computer-implemented method 800 returns to step 802 and increments to the next time period of the radiation therapy treatment fraction. If it is determined that the radiation doses for one or more locations within the region 602 are not within the specified limits and the remainder of the radiation therapy treatment fraction needs to be replanned, the computer-implemented method 800 proceeds to step 821.

[0090] In step 821, one or more remaining time periods of the radiation therapy procedure associated with the computer-implemented method 800 are replanned to compensate for the dose error detected in step 820. In some embodiments, the method is performed in conjunction with Figure 7 The computer-implemented method 800 then returns to step 802 and performs the next time period of the radiation therapy treatment fractionation.

[0091] In an embodiment of the computer-implemented method 800 described above, replanning of the radiation dose delivered to locations within the region 602 is performed for each time period of a radiation therapy fractionation. In other embodiments, this replanning of the radiation dose to be delivered is performed periodically, such as once every three, five, or ten time periods. In this embodiment, fewer computing resources are required to perform this replanning during a radiation therapy treatment fractionation.

[0092] Example computing device

[0093] Fig. 9 is an illustration of a computing device 900 configured to perform various embodiments described herein. For example, in some embodiments, the computing device 900 may be implemented as Figure 1The image acquisition and treatment control computer 106 and / or remote control console 110 in the present invention. The computing device 900 can be a desktop computer, a laptop computer, a smart phone, or any other type of computing device suitable for practicing one or more embodiments of the present disclosure. In operation, the computing device 900 is configured to execute instructions associated with the computer-implemented process 900, as described herein. Note that the computing device described herein is illustrative, and any other technically feasible configuration falls within the scope of the present disclosure.

[0094] As shown, computing device 900 includes, but is not limited to, an interconnect (bus) 940 connecting processing unit 950, an input / output device interface 960 coupled to input / output (I / O) device 980, memory 910, storage 930, and network interface 970. Processing unit 950 can be any suitable processor implemented as a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), any other type of processing unit, or a combination of different processing units, such as a CPU configured to operate in conjunction with a GPU or a digital signal processor (DSP). In general, processing unit 950 can be any technically feasible hardware unit capable of processing data and / or executing software applications, including computer-implemented process 500, computer-implemented process 700, and / or computer-implemented process 800.

[0095] I / O devices 980 may include devices capable of providing input, such as a keyboard, a mouse, a touch-sensitive screen, etc., and devices capable of providing output, such as a display device, etc. In addition, I / O devices 980 may include devices capable of both receiving input and providing output, such as a touch screen, a universal serial bus (USB) port, etc. I / O devices 980 may be configured to receive various types of input from an end user of the computing device 900, and also provide various types of output, such as a displayed digital image or digital video, to an end user of the computing device 900. In some embodiments, one or more of the I / O devices 980 are configured to couple the computing device 900 to a network.

[0096] The memory 910 may include a random access memory (RAM) module, a flash memory unit, or any other type of memory unit or combination thereof. The processing unit 950, the I / O device interface 960, and the network interface 970 are configured to read data from and write data to the memory 910. The memory 910 includes various software programs and application data associated with the software programs that can be executed by the processor 950, including the computer-implemented process 500, the computer-implemented process 700, and / or the computer-implemented process 800.

[0097] Example computer program product

[0098] Fig.10 1 is a block diagram of an illustrative embodiment of a computer program product 1000 for implementing a method of reducing scatter in an X-ray projection image according to various embodiments. The computer program product 1000 may include a signal bearing medium 1004. The signal bearing medium 1004 may include one or more sets of executable instructions 1002 that, when executed by, for example, a processor of a computing device, may provide at least the above-described Figures 1 to 8 Describes the functionality.

[0099] In some implementations, the signal bearing medium 1004 may include a non-transitory computer readable medium 1008, such as, but not limited to, a hard drive, a compact disc (CD), a digital video disc (DVD), a digital tape, a memory, etc. In some implementations, the signal bearing medium 1004 may include a recordable medium 1010, such as, but not limited to, a memory, a read / write (R / W) CD, a R / W DVD, etc. In some implementations, the signal bearing medium 1004 may include a communication medium 1006, such as, but not limited to, a digital and / or analog communication medium (e.g., an optical cable, a waveguide, a wired communication link, a wireless communication link, etc.). The computer program product 1000 may be recorded on the non-transitory computer readable medium 1008 or another similar recordable medium 1010.

[0100] In summary, the embodiments described herein can accurately determine the cumulative radiation dose even when significant intra-fraction motion of the patient's anatomy occurs during a radiotherapy treatment fraction. When the radiation dose during a radiotherapy treatment fraction deviates from the dosimetry target, subsequent fractions can be replanned to compensate. Thus, it helps to cover the target volume and keep the OARs safe.

[0101] The description of the various embodiments is presented for purposes of illustration, but is not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments.

[0102] The various aspects of the present embodiment may be embodied as a system, method or computer program product. Therefore, the various aspects of the present disclosure may take the form of a complete hardware embodiment, a complete software embodiment (including firmware, resident software, microcode, etc.) or an embodiment of a combination of software and hardware aspects, which may generally be referred to as a "circuit", "module" or "system" in this article. In addition, the various aspects of the present disclosure may take the form of a computer program product, which is embodied in one or more computer-readable media, and the computer-readable medium has a computer-readable program code embodied thereon.

[0103] Any combination of one or more computer-readable media may be utilized. A computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. A computer-readable storage medium may be, for example but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of computer-readable storage media would include the following: an electrical connection with one or more wires, a portable computer floppy disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer-readable storage medium may be any tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0104] Although various aspects and embodiments are disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and specific embodiments disclosed herein are for illustrative purposes only and are not intended to be limiting, with the true scope and spirit being indicated by the appended claims.

Claims

1. A computer-implemented method of determining a dose delivered by a radiation therapy system to a plurality of locations within a region of a patient's anatomy, the method comprising: placing the radiation therapy system in a first machine state during a first time period of a treatment fraction; delivering radiation to said region of the patient's anatomy during said first time period; generating a first surface map of the region of the patient's anatomy based on the surface measurements acquired during the first time period; generating a first modified digital volume for the region based on the first surface map; as well as For each location of the plurality of locations within the region of the patient anatomy, a first radiation dose delivered to the location during the first time period is determined, wherein the first radiation dose is based on the first machine state of the radiation therapy system and the first modified digital volume.

2. The computer-implemented method of claim 1 , wherein generating the first modified digital volume of the region comprises: A baseline digital volume of the region is deformably registered to the first surface map.

3. The computer-implemented method of claim 2, further comprising: acquiring an image of the region; as well as The baseline digital volume is reconstructed based on the imaging. The computer-implemented method of claim 3 , wherein the imaging is acquired prior to the treatment fractionation.

5. The computer-implemented method of claim 3, wherein the imaging is acquired during the treatment fractions.

6. The computer-implemented method of claim 3, wherein the imaging comprises one of: cone beam computed tomography (CBCT) imaging, magnetic resonance imaging, or computed tomography imaging.

7. The computer-implemented method of claim 1 , wherein generating the first modified digital volume of the region comprises: The first surface map is deformably registered to a baseline digital volume of the region.

8. The computer-implemented method of claim 1 , further comprising: For each location of the plurality of locations within the region of the patient anatomy, a second radiation dose delivered to the location during a second time period of the treatment fraction is determined.

9. The computer-implemented method of claim 8, wherein the second radiation dose is based on a second machine state of the radiation therapy system and a second modified digital volume of the region.

10. The computer-implemented method of claim 9, further comprising: The second modified digital volume of the region is generated by deformably registering the baseline digital volume of the region to the second surface map.

11. The computer-implemented method of claim 9, wherein the second modified digital volume of the region is based on a second surface map of the region of the patient anatomy, the second surface map being based on surface measurements acquired during a second time period.

12. The computer-implemented method of claim 1 , further comprising: For each location of the plurality of locations within the region of the patient anatomy, a total radiation dose delivered to the location during the treatment fractions is determined.

13. The computer-implemented method of claim 12, further comprising: For each of the plurality of locations within the region of the patient anatomy, a second radiation dose delivered to the location during a second time period of the treatment fraction is determined, wherein the total radiation dose delivered to the location during the treatment fraction is based on the first radiation dose delivered to the location during the first time period and the second radiation dose delivered to the location during the second time period.

14. A computer-implemented method for radiation therapy at a plurality of locations within a region of a patient's anatomy, the method comprising: determining a first total radiation dose delivered to a first location during a first treatment fraction, the first location being included in the plurality of locations, wherein the first radiation dose is based on a first time-resolved machine state of the radiation therapy system associated with the first treatment fraction and a time-resolved surface map of the region associated with the first treatment fraction; determining, based on the first total radiation dose, a dose error associated with the first location for the first treatment fraction; determining a second total radiation dose to be delivered to the first location in a second treatment fraction based on the dose error; based on the second total radiation dose, changing a time-resolved machine state of the radiation therapy system associated with the second treatment fraction from an original time-resolved machine state to a modified time-resolved machine state; and The second total radiation dose is delivered to the first location using the modified time-resolved machine state.

15. The computer-implemented method of claim 14, wherein the first time-resolved machine state comprises a set of values ​​of one or more process parameters associated with the radiation therapy system, wherein each of the one or more process parameters affects at least one of: a location of radiation delivery within the region during the first treatment fraction, and an intensity of radiation delivery within the region during the first treatment fraction.

16. The computer-implemented method of claim 15, wherein the set of values ​​for a process parameter of the one or more process parameters comprises: A value for each time period for the first treatment fraction.

17. The computer-implemented method of claim 14, wherein the second time-resolved machine state comprises a set of values ​​of one or more process parameters associated with the radiation therapy system, wherein each of the one or more process parameters affects at least one of: a location of radiation delivery within the region during the second treatment fraction, and an intensity of radiation delivery within the region during the second treatment fraction.

18. The computer-implemented method of claim 17, wherein changing the time-resolved machine state of the radiation therapy system associated with the second treatment fraction comprises: At least one value in the set of values ​​is changed.

19. The computer-implemented method of claim 14, wherein determining the first total radiation dose comprises: generating, based on the time-resolved surface map of the region, a different modified digital volume of the region for each of a plurality of time periods included in the first treatment fraction; as well as For each time period of the plurality of time periods, an incremental radiation dosage delivered to the first location during the time period is determined.

20. The computer-implemented method of claim 19, wherein the first total radiation dose comprises a sum of the incremental radiation doses for each of the plurality of time periods.

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