Measurement of radiation dose

Abstract

Provided herein is technology relating to the use of radiation for medical purposes, particularly, but not exclusively, to devices, systems, and methods for monitoring, inspecting, and maintaining medical radiation equipment as part of quality assurance programs. For example, the technology provides, in part, systems and methods for calculating tissue-phantom dose ratios (TPRs) used to characterize beams.

Description

[Technical Field]

[0001] This application claims priority to U.S. Provisional Patent Application No. 63 / 396,444, filed August 9, 2022, which is incorporated herein by reference in its entirety.

[0002] Provided herein is technology relating to the use of radiation for medical purposes, particularly, but not exclusively, to devices, systems, and methods for monitoring, inspecting, and maintaining medical radiation equipment as part of quality assurance programs. [Background technology]

[0003] Medical radiation systems utilize radiation sources for imaging and therapeutic purposes (e.g., in radiation therapy). The amount of radiation absorbed by a patient depends on several variables, including the radiation beam energy, the beam collimation, and the distance between the patient and the radiation source.

[0004] The radiation dose produced by a medical radiation system can be measured using a "phantom," typically a "water phantom" that comprises a tank filled with water. The water phantom closely approximates the radiation absorption and scattering properties of muscle and other soft biological tissues. The properties of the radiation beam after entering the tank and traveling through the water can be measured using a detector placed within the phantom (e.g., within the tank of the water phantom).

[0005] The tissue phantom ratio (TPR) is commonly measured to characterize the radiation dose delivered by a beam. TPR is defined as the ratio of the dose at a given point in the phantom to the dose at the same point at a fixed reference depth. For example, a common form of TPR is the TPR calculated using radiation measurements recorded at water levels of 10 cm and 20 cm in a water phantom: 20,10See, e.g., INTERNATIONAL COMMISSION ON RADIATION UNITS AND MEASUREMENTS, "Determination of Absorbed Dose in a Patient Irradiated by Beams of X or Gamma Rays in Radiotherapy Procedures," ICRU Rep. 24, ICRU Publications, Bethesda, MD (1976), incorporated herein by reference. See also, "Absorbed Dose Determination in External Beam Radiotherapy: An International Code of Practice for Dosimetry Based on Standards of Absorbed Dose to Water," Technical Reports Series No. 398, International Atomic Energy Agency, Vienna, 2000, incorporated herein by reference.

[0006] Current methods for measuring the tissue-phantom dose ratio (TPR) require holding the detector in a fixed position and obtaining radiation measurements at multiple water levels provided between the detector and the radiation source within the water phantom. The water level is typically adjusted manually or automatically by a self-draining mechanism. The draining process can be initially calibrated by a water sensor, usually mounted on the tank's moving mechanism. Additionally, a water reservoir system may be required to control the water level. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] US Patent Application Publication No. 2020 / 0268327 [Non-patent literature]

[0008] [Non-Patent Document 1] INTERNATIONAL COMMISSION ON RADIATION UNITS AND MEASUREMENTS, “Determination of Absorbed Dose in a Patient Irradiated by Beams of X or Gamma Rays in Radiotherapy Procedures”, ICRU Rep. 24, ICRU Publications, Bethesda, MD (1976) [Non-patent document 2] "Absorbed Dose Determination in External Beam Radiotherapy: An International Code of Practice for Dosimetry Based on Standards of Absorbed Dose to Water," Technical Reports Series No. 398, International Atomic Energy Agency, Vienna, 2000 (Section 4.2.3, Section 6.3.2, Table 6, Table 12, Figure 6) [Non-patent document 3] Murty (1965) “Effective Atomic Numbers of Heterogeneous Materials” Nature 207(4995):398-99 [Non-patent document 4] Taylor (2008) “The effective atomic number of dosimetric gels” Australasian Physics&Engineering Sciences in Medicine31(2):131-38 [Non-patent document 5] Taylor (2009) “Electron Interaction with Gel Dosimeters: Effective Atomic Numbers for Collisional, Radiative and Total Interaction Processes” Radiation Research 171(1):123-26 [Non-patent document 6] Taylor (2011) “Robust determination of effective atomic numbers for electron interactions with TLD-100 and TLD-100H thermoluminescent dosimeters” Nuclear Instruments and Methods in Physics Research Section B:Beam Interactions with Materials and Atoms 269(8):770-73 [Non-Patent Document 7] Taylor (2012) “Robust calculation of effective atomic numbers: The Auto-Zeff software” Medical Physics 39(4):1769-78 [Non-patent document 8] “Tissue Substitutes in Radiation Dosimetry and Measurement” (1989) INTERNATIONAL COMMISSION ON RADIATION UNITS AND MEASUREMENTS, Rep. 44, ICRU, Bethesda, Maryland [Non-Patent Document 9] Agostinelli (1992) “A new water-equivalent plastic for dosimetry calibration” Med.Phys.19:774 Summary of the Invention [Problem to be solved by the invention]

[0009] There is a need for new or improved methods for measuring radiation dose in medical radiation systems. [Means for solving the problem]

[0010] Thus, provided herein are embodiments of technology relating to the use of radiation for medical purposes, particularly, but not exclusively, to devices, systems, and methods for monitoring, inspecting, and maintaining medical radiation equipment as part of a quality assurance program.

[0011] For example, in some embodiments, the technology provides a phantom. In some embodiments, the phantom comprises a tank, and the tank comprises water. The water can also be approximated by a solid material (e.g., plastic). See, for example, section 4.2.3 and Table 6 of "Absorbed Dose Determination in External Beam Radiotherapy: An International Code of Practice for Dosimetry Based on Standards of Absorbed Dose to Water," Technical Reports Series No. 398, International Atomic Energy Agency, Vienna, 2000 (incorporated herein by reference). Thus, in some embodiments, the phantom comprises a solid water equivalent. The solid water phantoms described herein offer advantages over phantoms comprising liquid water, for example, when measuring radiation dose during acceleration or deceleration of the phantom, or any time when rotation or translation of the liquid water phantom changes the liquid water level. The technology provided herein relates to embodiments of phantoms comprising liquid water ("water phantoms") and embodiments of phantoms comprising solid water equivalents ("solid phantoms").

[0012] In some embodiments, the phantom is a water phantom. In some embodiments, the water phantom comprises: a tank having a base, a first wall (e.g., a radiolucent wall), and a second wall (e.g., a radiolucent wall); a detector positioned within the tank a first distance from the first wall and a second distance from the second wall; and water. In some embodiments, the first wall and / or the second wall comprise poly(methyl methacrylate). In some embodiments, the first wall is at a 90° angle from the second wall. In some embodiments, the detector has a cylindrical shape. In some embodiments, the detector has a first detection surface parallel (e.g., substantially and / or virtually parallel) to the first wall and a second detection surface parallel (e.g., substantially and / or virtually parallel) to the second wall. In some embodiments, the first distance is 10 cm and the second distance is 20 cm. Thus, in some embodiments, the water phantom is a TPR 20,10 In some embodiments, the TPR is used to calculate 20,10 are 20 and 10 g / cm 2 The tissue phantom dose ratio for a 10 cm x 10 cm field size and a 100 cm source-chamber distance in water at a depth of 1000 m is used as a beam quality index. See, e.g., "Absorbed Dose Determination in External Beam Radiotherapy: An International Code of Practice for Dosimetry Based on Standards of Absorbed Dose to Water," Technical Reports Series No. 398, International Atomic Energy Agency, Vienna, 2000 (incorporated herein by reference), in particular Section 6.3.2, Table 12, and / or Figure 6 of this reference.

[0013] In some embodiments, the water phantom further comprises a component (e.g., an interface, a mounting component, etc.) structured to attach the water phantom to a patient support assembly. In some embodiments, a detector is located at the axis of rotation of the water phantom. In some embodiments, the water phantom further comprises a movable arm operably engaged with the detector.

[0014] In some embodiments, the phantom is a solid phantom. In some embodiments, the solid phantom comprises a solid water-equivalent material, the solid phantom comprising a first exterior surface and a second exterior surface; and a detector positioned within the solid phantom a first distance from the first exterior surface and a second distance from the second exterior surface. In some embodiments, the solid phantom comprises a hole, and the detector is located within the hole. In some embodiments, the solid phantom comprises a hole a first distance from the first exterior surface and a second distance from the second exterior surface, and the detector is located within the hole. In some embodiments, the first exterior surface is at a 90° angle from the second exterior surface. In some embodiments, the detector has a cylindrical shape. In some embodiments, the detector has a first detection surface parallel (e.g., substantially and / or virtually parallel) to the first exterior surface and a second detection surface parallel (e.g., substantially and / or virtually parallel) to the second exterior surface. In some embodiments, the first distance is 10 cm and the second distance is 20 cm. Thus, in some embodiments, the solid phantom is a TPR 20,10 In some embodiments, the solid phantom further comprises a component (e.g., an interface, a mounting component, etc.) structured to attach the solid phantom to a patient support assembly. In some embodiments, a detector is located at the axis of rotation of the solid phantom. In some embodiments, the solid phantom further comprises a movable arm operably engaged to the detector.

[0015] In some embodiments, the present technology provides a system for measuring radiation dose. In some embodiments, the system includes a phantom (e.g., a water phantom or a solid phantom) comprising a detector, and further includes an electrometer, a slip ring, and a computer. In some embodiments, the phantom's detector is in electrical or electronic communication with the electrometer. In some embodiments, the phantom's detector and the electrometer are on the same side of the slip ring. That is, in embodiments, the phantom's detector outputs a signal to the electrometer, and the signal does not pass through a slip ring between the phantom's detector and the electrometer. Thus, in some embodiments, the phantom's detector and the electrometer are in direct electrical communication. In some embodiments, the phantom's detector is in electrical or electronic communication with the electrometer through a cable connecting the detector and the electrometer. In some embodiments, the cable connecting the detector and the electrometer is a triaxial cable. In some embodiments, the electrometer is in electrical or electronic communication with a microprocessor (e.g., a computer). In some embodiments, the electrometer outputs a signal that is communicated to the microprocessor (e.g., a computer). In some embodiments, the electrometer outputs a signal that is communicated to the microprocessor (e.g., a computer) across the slip ring. In some embodiments, the system further comprises an analog-to-digital converter that converts the electrical (e.g., analog) signal produced by the electrometer into a digital signal for communication (e.g., across a slip ring) to a microprocessor.

[0016] The present technology further provides method embodiments. For example, in some embodiments, the present technology provides a method for measuring a radiation dose provided by a medical radiation system. In some embodiments, the medical radiation system includes a radiation source (e.g., a stationary source) and a patient rotation system configured to rotate about an axis of rotation. In some embodiments, the method includes placing a phantom (e.g., a water phantom or a solid phantom) on a patient support assembly of the patient rotation system. In some embodiments, the water phantom includes a liquid (e.g., water) and a detector immersed in the liquid. In some embodiments, the liquid is water, an aqueous solution, and / or a composition comprising water. In some embodiments, the solid phantom includes a solid water equivalent, and the detector is placed within the solid water equivalent. In some embodiments, the method further includes moving (e.g., rotating) the phantom relative to a radiation beam generated by the radiation source; detecting the radiation beam using the detector; and calculating a radiation dose of the radiation beam. In some embodiments, detecting the radiation beam occurs while the phantom is moving (e.g., rotating). In some embodiments, the radiation beam is detected multiple times (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or more than 10 times) while the phantom is moving (e.g., rotating). In some embodiments, the method includes moving (e.g., rotating) the phantom, stopping the movement (e.g., rotation) of the phantom, and detecting radiation while the phantom is stationary. In some embodiments, the method includes moving (e.g., rotating) the phantom, stopping the movement (e.g., rotation) of the phantom, detecting radiation while the phantom is stationary, and moving (e.g., rotating) the phantom again.In some embodiments, the method includes multiple repetitions (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or more than 10 times) of moving (e.g., rotating) the phantom, stopping the movement (e.g., rotation) of the phantom, and detecting radiation while the phantom is stationary.

[0017] For example, in some embodiments, the present technology provides a method for measuring a radiation dose provided by a medical radiation system including a radiation source (e.g., a stationary source) and a patient rotation system configured to rotate about an axis of rotation. In some embodiments, the method includes placing a phantom (e.g., a water phantom or a solid phantom) on a patient support assembly of the patient rotation system; moving the phantom relative to a radiation beam generated by the radiation source; detecting the radiation beam using a detector; and calculating a radiation dose of the radiation beam. In some embodiments, the phantom is a water phantom including a tank with a liquid and a detector immersed in the liquid (e.g., water, an aqueous solution, and / or a composition comprising water). In some embodiments, the phantom is a solid phantom including a solid water-equivalent material and a detector placed within the solid phantom (e.g., in a hole provided in the solid phantom). In some embodiments, the phantom is placed on the patient support assembly such that the axis of rotation passes through the phantom. In some embodiments, the phantom is placed on the patient support assembly such that a side wall or an exterior surface of the phantom faces the radiation source and the radiation beam passes through the side wall or exterior surface. In some embodiments, the sidewalls or exterior surface are perpendicular to the central axis of the radiation beam. In some embodiments, the sidewalls are transparent to the radiation beam. In some embodiments, the solid phantom comprises a solid water-equivalent material that is transparent to the radiation beam.

[0018] In some embodiments, moving the phantom (e.g., a water phantom or a solid phantom) comprises rotating the phantom by rotating a patient rotation system about an axis of rotation. In some embodiments, moving the phantom comprises translating the phantom by translating a patient support assembly relative to the patient rotation system. In some embodiments, the detector is movable within the phantom.

[0019] In some embodiments, detecting the radiation beam includes positioning a detector to intercept the radiation beam by moving a phantom (e.g., a water phantom or a solid phantom) and / or by moving the detector within the phantom. In some embodiments, detecting the radiation beam includes detecting the radiation beam at multiple locations within the phantom (e.g., using multiple detectors and / or by moving a detector to multiple locations within the phantom).

[0020] In some embodiments, calculating the radiation dose of the radiation beam includes generating a three-dimensional intensity profile of the radiation beam within a phantom (e.g., a water phantom or a solid phantom). In some embodiments, the detector is positioned on an axis of rotation.

[0021] In some embodiments, the calculated radiation dose is a first radiation dose obtained for a first orientation of the phantom (e.g., a water phantom or a solid phantom), and the method further includes: rotating the phantom to a second orientation different from the first orientation by rotating the patient rotation system about a rotation axis; detecting the radiation beam for the second orientation using a detector; calculating a second radiation dose of the radiation beam for the second orientation; and comparing the second radiation dose to the first radiation dose to obtain a tissue phantom dose ratio. In some embodiments, the length of a first propagation path of the radiation beam within the phantom for the first orientation is different from the length of a second propagation path of the radiation beam within the phantom for the second orientation. In some embodiments, the length of the first propagation path is X cm; the length of the second propagation path is Y cm; and the tissue phantom dose ratio is TPR. X,Y These are the measured values.

[0022] In some embodiments, X is between 1 and 100 cm (e.g., 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 cm). In some embodiments, Y is between 1 and 100 cm (e.g., 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 cm). In an exemplary embodiment, the length of the first propagation path is 10 cm (e.g., X); the length of the second propagation path is 20 cm (e.g., Y); and the tissue-phantom dose ratio is TPR. 20,10 These are the measured values.

[0023] In some embodiments, a solid phantom is used. In some embodiments, the solid phantom comprises a material suitable for measuring X-rays having a particular energy to be examined. In some embodiments, the phantom comprises a first hole located at a depth of X cm from the outer surface of the phantom. In some embodiments, the phantom comprises a second hole located at a depth of Y cm from the outer surface of the phantom. In some embodiments, the depth X of the first hole is between 1 and 100 cm (e.g., 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 cm). In some embodiments, the depth Y of the second hole is 1 to 100 cm (e.g., 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 cm). In some embodiments, the solid phantom comprises a hole (e.g., a single hole) that is at a depth of X cm from the first exterior surface of the phantom and at a depth of Y cm from the second exterior surface of the phantom. In some embodiments, the depth X of the hole is 1 to 100 cm (e.g., 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 cm) from the first exterior surface of the phantom, and the depth Y of the hole is 1 to 100 cm (1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 cm) from the second exterior surface of the phantom. In an exemplary embodiment, the solid phantom comprises a first hole 10 cm deep from the exterior surface of the phantom and / or a second hole 20 cm deep from the exterior surface of the phantom. In an exemplary embodiment, the solid phantom comprises a single hole located 10 cm deep from the first exterior surface of the phantom and / or 20 cm deep from the second exterior surface of the phantom.

[0024] In some embodiments, the holes are drilled to provide compensation for chamber disturbances to the fluence. In some embodiments, the holes are drilled with the compensation addressed a priori. As described herein, in an exemplary embodiment, a solid phantom comprising one or more holes (e.g., each at a depth of 1 to 100 cm (e.g., 10 cm and / or 20 cm) from the first and / or second exterior surfaces) can be rotated into position regardless of inertial forces of the liquid that cause the device material to sway.

[0025] In some embodiments, the propagation path length and / or hole depth may vary from the nominal X and Y values described herein (e.g., by about ±10% (e.g., ±1 to 10% (e.g., ±1, 2, 3, 4, 5, 6, 7, 8, 9, or 10%)) to, for example, address the effective points of measurement of the detector. Thus, in some embodiments, the present technology provides a method that includes placing a phantom at a location relative to the detector that provides one or more effective points of measurement at the X and Y distances. In some embodiments, the present technology provides a system that includes a phantom placed at a location relative to the detector that provides one or more effective points of measurement at the X and Y distances.

[0026] In some embodiments, the technique uses a detector that provides a substantially symmetric response to measurements of the phantom in a first orientation and a second orientation, hi some embodiments, a correction factor is determined for measurements made with the phantom in the first orientation and for measurements made with the phantom in the second orientation.

[0027] In some embodiments, in a first orientation, a first side wall or outer surface of the phantom (e.g., a water phantom or a solid phantom) facing the radiation source is perpendicular to the central axis of the radiation beam. In some embodiments, in a second orientation, a second side wall or outer surface of the phantom facing the radiation source is perpendicular to the central axis of the radiation beam. In some embodiments, the radiation source is an imaging radiation source or a therapeutic radiation source.

[0028] In some embodiments, the axis of rotation (eg, the central axis of the radiation beam) is perpendicular to the radiation beam. In some embodiments, the axis of rotation is a perpendicular axis.

[0029] In some embodiments, the phantom (e.g., a water phantom or a solid phantom) is securely attached to the patient support assembly. In some embodiments, the patient support assembly includes an interface for attaching the phantom to a fixed position on the patient support assembly. In some embodiments, the phantom is mounted to a seat member of the patient support assembly. In some embodiments, the phantom is mounted to an armrest of the patient support assembly. In some embodiments, the phantom is placed on a horizontal surface of the patient support assembly. In some embodiments, the phantom is disposed horizontally on the patient support assembly such that the central axis of the radiation beam is parallel (e.g., substantially and / or virtually parallel) to the base of the phantom.

[0030] Further embodiments of the present technology relate to systems. For example, in some embodiments, the present technology provides a system comprising: a medical radiation system; a phantom (e.g., a water phantom or a solid phantom) comprising a base, a first wall (e.g., a radiolucent wall) or a first external surface, and a second wall (e.g., a radiolucent wall) or a second external surface; and a detector positioned within the phantom at a first distance from the first wall or the first external surface and a second distance from the second wall or the second external surface. In some embodiments, the phantom is a water phantom comprising a tank (e.g., comprising a base, a first wall, and a second wall) and a liquid (e.g., water, an aqueous solution, and / or a composition comprising water). In some embodiments, the phantom is a solid phantom (e.g., comprising a solid water-equivalent material comprising a base, a first external surface, and a second external surface). In some embodiments, the solid phantom comprises several holes. In some embodiments, the solid phantom comprises a detector installed in the hole. In some embodiments, the solid phantom comprises a plurality of holes and a plurality of detectors, each of the plurality of detectors being positioned within a hole.

[0031] In some embodiments, the system further comprises a source (e.g., a stationary source). In some embodiments, the system further comprises a beam (e.g., a beam produced by a source).

[0032] In some embodiments, the system further comprises a patient support assembly. In some embodiments, the patient support assembly comprises an interface structured to receive the phantom. In some embodiments, the patient support assembly is structured to operatively engage the phantom. In some embodiments, the patient support assembly is structured to translate the phantom. In some embodiments, the patient support assembly is structured to rotate the phantom.

[0033] In some embodiments, the system comprises a phantom (e.g., a water phantom or a solid phantom) comprising a detector, and further comprises an electrometer, a slip ring, and a computer. In some embodiments, the detector is in electrical or electronic communication with the electrometer. In some embodiments, the detector is in electrical or electronic communication with the electrometer through a cable connecting the detector and the electrometer. In some embodiments, the cable connecting the detector and the electrometer is a triaxial cable. In some embodiments, the electrometer is in electrical or electronic communication with a microprocessor (e.g., a computer). In some embodiments, the electrometer outputs a signal that is communicated to the microprocessor (e.g., a computer). In some embodiments, the electrometer outputs a signal that is communicated to the microprocessor (e.g., a computer) across a slip ring. In some embodiments, the system further comprises an analog-to-digital converter that converts the electrical (e.g., analog) signal produced by the electrometer into a digital signal for communication to the microprocessor (e.g., across the slip ring).

[0034] Thus, in some embodiments, the system is a phantom system comprising: a phantom comprising a detector; a slip ring; a microprocessor; and an electrometer in electronic or electrical communication with the detector through a cable and in electronic or electrical communication with the microprocessor through the slip ring. In some embodiments, the phantom is a water phantom. In some embodiments, the phantom is a solid phantom. In some embodiments, the cable is a triaxial cable. In some embodiments, the computer comprises the electrometer. In some embodiments, the phantom system further comprises an analog-to-digital converter in electrical communication with the electrometer. In some embodiments, the phantom system comprises a rotating subsystem comprising the phantom and the electrometer. In some embodiments, the phantom system comprises a non-rotating subsystem comprising the microprocessor.

[0035] In some embodiments, the present technology relates to a method for measuring a radiation dose provided by a medical radiation system including a patient rotation system and a radiation source. The patient rotation system is configured to rotate about an axis of rotation. For example, in some embodiments, the method includes placing a phantom of a phantom system on a patient support assembly of the patient rotation system; moving the phantom relative to a radiation beam generated by the radiation source; detecting the radiation beam using a detector; producing an electrical signal characterizing the radiation beam with an electrometer; communicating the electrical signal from the electrometer to a microprocessor through a slip ring; and calculating a radiation dose of the radiation beam using the signal. In some embodiments, the phantom is placed on the patient support assembly such that the axis of rotation passes through the phantom. In some embodiments, moving the phantom includes rotating the phantom by rotating the patient rotation system about the axis of rotation. In some embodiments, detecting the radiation beam includes detecting the radiation beam at multiple locations within the phantom. In some embodiments, calculating the radiation dose of the radiation beam includes generating a three-dimensional intensity profile of the radiation beam within the phantom. In some embodiments, the detector is aligned with the axis of rotation.

[0036] In some embodiments, the calculated radiation dose is a first radiation dose obtained for a first orientation of the phantom, and the method further includes: rotating the phantom to a second orientation different from the first orientation by rotating the patient rotation system about a rotation axis; detecting the radiation beam for the second orientation using a detector; producing a second electrical signal characterizing the radiation beam for the second orientation by an electrometer; communicating the second electrical signal from the electrometer to a microprocessor through a slip ring; calculating a second radiation dose of the radiation beam for the second orientation; and comparing the second radiation dose to the first radiation dose to obtain a tissue-phantom dose ratio. In some embodiments, the length of a first propagation path of the radiation beam within the phantom for the first orientation is different from the length of a second propagation path of the radiation beam within the phantom for the second orientation. In some embodiments, the length of the first propagation path is X cm; the length of the second propagation path is Y cm; and the tissue-phantom dose ratio is TPR. X,Y In some embodiments, X is between 1 and 100 cm (e.g., 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 cm). In some embodiments, Y is between 1 and 100 cm (e.g., 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 cm). In an exemplary embodiment, the length of the first propagation path is 10 cm (e.g., X); the length of the second propagation path is 20 cm (e.g., Y); and the tissue-phantom dose ratio is TPR. 20,10 These are the measured values.

[0037] In some embodiments, the present technology relates to a method for measuring one or more radiation dose characteristics (e.g., radiation dose flux, accumulated radiation dose, radiation dose symmetry, radiation dose profile shape, radiation dose penumbra, radiation dose distribution) provided by a medical radiation system including a patient rotation system and a radiation source. The patient rotation system is configured to rotate about a rotation axis. In some embodiments, measuring the one or more radiation dose characteristics (e.g., radiation dose flux, accumulated radiation dose, radiation dose symmetry, radiation dose profile shape, radiation dose penumbra, and / or radiation dose distribution) includes placing a phantom of a phantom system on a patient support assembly of the patient rotation system; moving the phantom relative to a radiation beam generated by the radiation source; detecting the radiation beam using a detector; producing an electrical signal characterizing the radiation beam by an electrometer; communicating the electrical signal from the electrometer through a slip ring to a microprocessor; and calculating the one or more radiation dose characteristics (e.g., radiation dose flux, accumulated radiation dose, radiation dose symmetry, radiation dose profile shape, radiation dose penumbra, radiation dose distribution) of the radiation beam using the signal. In some embodiments, the phantom is positioned on the patient support assembly such that the axis of rotation passes through the phantom. In some embodiments, moving the phantom includes rotating the phantom by rotating the patient rotation system about the axis of rotation. In some embodiments, detecting the radiation beam includes detecting the radiation beam at multiple locations within the phantom. In some embodiments, calculating one or more radiation dose characteristics of the radiation beam includes generating a three-dimensional intensity profile of the radiation beam within the phantom. In some embodiments, the detector is aligned with the axis of rotation.

[0038] In some embodiments, the one or more radiation dose characteristics are first radiation dose characteristics obtained for a first orientation of the phantom, and the method further includes: rotating the phantom to a second orientation different from the first orientation by rotating the patient rotation system about the rotation axis; detecting the radiation beam for the second orientation using a detector; producing a second electrical signal characterizing the radiation beam for the second orientation by an electrometer; communicating the second electrical signal from the electrometer to a microprocessor through a slip ring; calculating a second radiation dose characteristic (e.g., radiation dose flux, cumulative radiation dose, radiation dose symmetry, radiation dose profile shape, radiation dose penumbra, radiation dose distribution) of the radiation beam for the second orientation; and comparing the second radiation dose characteristic with the first radiation dose characteristic. In some embodiments, comparing the second radiation dose characteristic with the first radiation dose characteristic results in a tissue-phantom dose ratio. In some embodiments, the length of the first propagation path is X cm; and the length of the second propagation path is Y cm. In some embodiments, the tissue-phantom dose ratio is TPR X,Y In some embodiments, X is between 1 and 100 cm (e.g., 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 cm). In some embodiments, Y is between 1 and 100 cm (e.g., 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 cm). In an exemplary embodiment, the length of the first propagation path is 10 cm (e.g., X); the length of the second propagation path is 20 cm (e.g., Y). In some embodiments, the tissue-phantom dose ratio is calculated as TPR 20,10 These are the measured values.

[0039] In some embodiments, in a first orientation, a first side wall or exterior surface of the phantom facing the radiation source is perpendicular to the central axis of the radiation beam. In some embodiments, in a second orientation, a second side wall or exterior surface of the phantom facing the radiation source is perpendicular to the central axis of the radiation beam. In some embodiments, the radiation source is one of an imaging radiation source or a therapeutic radiation source. In some embodiments, the axis of rotation is perpendicular to the radiation beam. In some embodiments, the axis of rotation is a vertical axis. In some embodiments, the phantom is rigidly attached to a patient support assembly. In some embodiments, the patient support assembly includes an interface for attaching the phantom to a fixed position on the patient support assembly. In some embodiments, the phantom is mounted to a seat member of the patient support assembly. In some embodiments, the phantom is mounted to an armrest of the patient support assembly. In some embodiments, the phantom is placed on a horizontal surface of the patient support assembly. In some embodiments, the phantom is disposed horizontally on the patient support assembly such that the central axis of the radiation beam is parallel to the base of the phantom. In some embodiments, the phantom is a water phantom including a tank, water, and a detector. In some embodiments, the phantom is a solid phantom comprising a solid water-equivalent material and a detector.

[0040] In some embodiments, the systems described herein further comprise a software component including instructions for rotating the phantom. In some embodiments, the systems further comprise a software component including instructions for activating a source to create a beam. In some embodiments, the systems further comprise a software component including instructions for receiving data from the detector and using the data to calculate a tissue-phantom dose ratio. In some embodiments, the tissue-phantom dose ratio is calculated using the TPR 20,10In some embodiments, the first wall and / or the second wall comprise poly(methyl methacrylate). In some embodiments, the first wall is at a 90° angle from the second wall. In some embodiments, the first exterior surface is at a 90° angle from the second exterior surface. In some embodiments, the detector has a cylindrical shape. In some embodiments, the detector has a first detection surface that is parallel (e.g., substantially and / or virtually parallel) to the first wall or first exterior surface; and a second detection surface that is parallel (e.g., substantially and / or virtually parallel) to the second wall or second exterior surface. In some embodiments, the first distance between the first detection surface of the detector and the first wall or first exterior surface is 10 cm, and the second distance between the second detection surface of the detector and the second wall or second exterior surface is 20 cm.

[0041] In some embodiments, the method includes providing and / or using a correction factor to account for differences in mass attenuation and / or density between materials. For example, acrylic materials have a mass attenuation of 1.18 g / cm 3 has a density of 1.00 g / cm3, while water has a density of 1.00 g / cm3 3 It has a density of

[0042] Furthermore, the point of measurement for the cylindrical phantom is on the central axis of the phantom, and therefore, when measuring dose at individual points, the central axis is located at the reference depth. The effective point of measurement is closer to the source compared to the point of measurement, mainly due to the forward direction of the secondary electrons. Therefore, the depth-dose curve is shifted towards the source (e.g., to a shallower depth). For cylindrical and spherical chambers, this shift is 0.6r for the photon beam. cav , 0.5 with electron beam rcav where rcav is the radius of the ionization chamber cavity.

[0043] Some portions of this description describe embodiments of the technology in terms of algorithms and symbolic representations of operations on information. These algorithmic descriptions and representations are commonly used by those skilled in the data processing arts to effectively convey the substance of their work to others skilled in the art. These operations, while described functionally, computationally, or logically, will be understood to be implemented by computer programs or equivalent electrical circuits, microcode, or the like. Further, it has proven convenient at times to refer to these arrangements of operations as modules, without loss of generality. The described operations and their associated modules may be embodied in software, firmware, hardware, or any combination thereof.

[0044] Certain steps, operations, or processes described herein may be performed or implemented in one or more hardware or software modules, alone or in combination with other devices. In some embodiments, software modules are implemented in a computer program product that includes a computer-readable medium containing computer program code. The computer program code may be executed by a computer processor to perform any or all of the described steps, operations, or processes.

[0045] In some embodiments, the system comprises a computer and / or data storage that is virtually provided (e.g., as a cloud computing resource). In particular embodiments, the present technology involves the use of cloud computing to provide a virtual computer system that comprises computer components and / or performs functions as described herein. Thus, in some embodiments, cloud computing provides infrastructure, applications, and software as described herein through a network and / or via the Internet. In some embodiments, computing resources (e.g., data analysis, calculations, data storage, application programs, file storage, etc.) are provided remotely via a network (e.g., the Internet and / or a cellular network).

[0046] Embodiments of the present technology also relate to apparatus for performing the operations herein. The apparatus may be specially structured for the required purposes and / or may include a general-purpose computing device selectively activated or reconfigured by a computer program stored in the computer. Such a computer program may be stored on a non-transitory, tangible, computer-readable storage medium that can be coupled to a computer system bus or any type of medium suitable for storing electronic instructions. Furthermore, the computing systems referred to herein may include a single processor or may be architectures employing multiple processor designs to increase computing power.

[0047] Additional embodiments will be apparent to those skilled in the art based on the teachings contained herein.

[0048] The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.

[0049] These and other features, aspects, and advantages of the present technology will become better understood with regard to the following drawings. [Brief explanation of the drawings]

[0050] [Figure 1A] 1 is a schematic diagram illustrating a perspective view of an exemplary medical radiation system. [Figure 1B] 1 is a schematic diagram showing a top view of a medical radiology system. [Figure 1C] 1 is a schematic diagram showing a top view of a medical radiation system with a patient positioned in the path of the beam. [Figure 1D] 1 is a schematic diagram showing a top view of a medical radiation system with two sources, with a patient positioned in the path of a beam produced by one of the two sources. [Figure 1E] 1 is a schematic diagram showing a top view of a medical radiation system with two sources, with a patient positioned in the path of a beam produced by one of the two sources. [Figure 1F] 1 is a schematic diagram showing a top view of a medical radiation system with a water phantom positioned in the path of the beam. [Figure 2] 1 is a block diagram of an exemplary method for measuring radiation dose provided by a medical radiation system. [Figure 3] 1 is a schematic diagram illustrating a top view of an exemplary system for performing a three-dimensional radiation dose scan. [Figure 4A] 1A and 1B are schematic diagrams showing a top view of an exemplary system for measuring tissue-phantom dose ratio (TPR).FIG. 1A is a schematic diagram of a phantom for performing TPR measurements in a first orientation. [Figure 4B]1 is a schematic diagram showing a top view of an exemplary system for measuring tissue-phantom dose ratio (TPR). [Figure 5A] 1 is a schematic diagram of an embodiment of a phantom system comprising a phantom, an electrometer, and a slip ring. [Figure 5B] 1 is a schematic diagram of an embodiment of a phantom system comprising a phantom, an electrometer, and a slip ring. DETAILED DESCRIPTION OF THE INVENTION

[0051] It should be understood that the figures are not necessarily drawn to scale, and that objects in the figures are not necessarily drawn to scale relative to each other. The figures are representations intended to provide clarity and understanding to various embodiments of the devices, systems, and methods disclosed herein. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or similar parts. It should also be understood that the drawings are not intended to limit the scope of the present teachings in any way.

[0052] Provided herein are embodiments of technology relating to the use of radiation for medical purposes, particularly, but not exclusively, to devices, systems, and methods for monitoring, inspecting, and maintaining medical radiation equipment as part of quality assurance programs.

[0053] In this detailed description of various embodiments, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. However, those skilled in the art will recognize that the various embodiments may be practiced without these specific details. In other instances, structures and devices are shown in block diagram form. Furthermore, those skilled in the art will readily appreciate that the specific order in which the methods are presented and performed is illustrative, and it is contemplated that the order can be changed and still remain within the spirit and scope of the various embodiments disclosed herein.

[0054] All literature and similar materials cited in this application, including but not limited to patents, patent applications, papers, books, articles, and Internet web pages, are expressly incorporated by reference in their entirety for any purpose. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the various embodiments described herein belong. When definitions of terms in incorporated references appear to differ from definitions provided in the present teachings, the definitions provided in the present teachings shall control. The section headings used herein are for organizational purposes only and should not be construed in any way as limiting the subject matter described.

[0055] definition To facilitate understanding of the present technology, several terms and phrases are defined below. Additional definitions are set forth throughout the detailed description.

[0056] Throughout the specification and claims, the following terms take the meanings expressly associated therewith herein, unless the context clearly dictates otherwise. As used herein, the phrase "in one embodiment" does not necessarily refer to the same embodiment, although it may. Further, as used herein, the phrase "in another embodiment" does not necessarily refer to different embodiments, although it may. Thus, as described below, various embodiments of the invention can be readily combined without departing from the scope or spirit of the invention.

[0057] Also, as used herein, the term "or" is an inclusive "or" operator and is equivalent to the term "and / or" unless the context clearly dictates otherwise. The term "based on" is not exclusive and allows for the basis of additional unexplained factors unless the context clearly dictates otherwise. Also, throughout the specification, the meanings of "a," "an," and "the" include plural references. The meaning of "in" includes "in" and "on."

[0058] As used herein, the terms "about," "approximately," "substantially," and "significantly" will be understood by those of ordinary skill in the art and will vary to some extent depending on the context in which they are used. If there are uses of these terms that are not clear to persons of ordinary skill in the art given the context in which they are used, "about" and "approximately" mean plus or minus 10% or less of the particular term, and "substantially" and "significantly" mean plus or minus more than 10% of the particular term.

[0059] As used herein, the disclosure of a range includes the disclosure of all values within the entire range, including the endpoints and subranges given therein, and further divided ranges. As used herein, the disclosure of a numerical range includes the endpoints and each intermediate number therebetween, to the same degree of precision. For example, for the range 6-9, the numbers 7 and 8 are contemplated in addition to 6 and 9, and for the range 6.0-7.0, the numbers 6.0, 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, 6.9, and 7.0 are expressly contemplated.

[0060] As used herein, the suffix "-free" refers to an embodiment of a technology that omits features of the base stem of the word to which "-free" is added. That is, the term "X-free" as used herein means "without X," where X is the feature of the technology omitted in the "X-free" technology. For example, a "calcium-free" composition does not contain calcium, a "blending-free" method does not include a blending step, etc.

[0061] As used herein, terms such as "first," "second," "third," and the like may be used to describe various steps, elements, compositions, components, regions, layers, and / or sections; however, these steps, elements, compositions, components, regions, layers, and / or sections should not be limited by these terms unless otherwise specified. These terms are used to distinguish one step, element, composition, component, region, layer, and / or section from another step, element, composition, component, region, layer, and / or section. As used herein, terms such as "first," "second," and other numerical terms do not imply an order or ranking unless clearly indicated by context. Thus, a first step, element, composition, component, region, layer, or section discussed herein could be referred to as a second step, element, composition, component, region, layer, or section without departing from the art.

[0062] As used herein, the words "presence" or "absence" (or "present" or "absence") are used in a relative sense to describe the amount or level of a particular entity (e.g., a component, action, element). For example, when an entity is said to be "present," this means that the level or amount of the entity is above a predetermined threshold. Conversely, when an entity is said to be "absent," this means that the level or amount of the entity is below a predetermined threshold. The predetermined threshold may be a detectability threshold associated with a particular test used to detect the entity, or any other threshold. If an entity is "detected," it is "present," and if an entity is "not detected," it is "absent."

[0063] As used herein, "increase" or "decrease" refers to a detectable (e.g., measured) positive or negative change in the value of a variable relative to a previously measured value, relative to a pre-established value, and / or relative to a standard control value, respectively. An increase is preferably at least a 10%, more preferably a 50%, even more preferably a 2-fold, even more preferably at least a 5-fold, and most preferably at least a 10-fold positive change relative to a previously measured value, pre-established value, and / or standard control value. Similarly, a decrease is preferably at least a 10%, more preferably a 50%, even more preferably at least an 80%, and most preferably at least a 90% negative change relative to a previously measured value, pre-established value, and / or standard control value. Other terms indicating quantitative changes or differences, such as "more" or "less," are used herein in the same manner as above.

[0064] As used herein, a "system" refers to multiple actual and / or abstract components that work together for a common purpose. In some embodiments, a "system" is an integrated collection of hardware and / or software components. In some embodiments, each component of a system interacts with and / or is related to one or more other components. In some embodiments, a system refers to a combination of components and software for controlling and directing a method. For example, a "system" or a "subsystem" may include one or more of the following, or a combination thereof: mechanical devices, hardware, hardware components, circuits, circuit configurations, logical designs, logical components, software, software modules, components of software or software modules, software procedures, software instructions, software routines, software objects, software functions, software classes, software programs, files containing software, and the like, for performing the functions of the system or subsystem. Thus, the methods and apparatus of the embodiments, or certain aspects or portions thereof, may take the form of program code (e.g., instructions) embodied in a tangible medium, such as a floppy disk, a CD-ROM, a hard drive, a flash memory, or any other machine-readable storage medium. When program code is loaded and executed on a machine, such as a computer, the machine becomes an apparatus for practicing the embodiments. In the case of program code running on a programmable computer, the computing device generally includes a processor, a processor-readable storage medium (e.g., volatile and non-volatile memory and / or storage elements), at least one input device, and at least one output device. One or more programs may implement or utilize the processes described in connection with the embodiments, for example, through the use of application programming interfaces (APIs), reusable controls, etc. Such programs are preferably implemented in a high-level procedural or object-oriented programming language to communicate with a computer system.However, the programs may preferably be implemented in assembly or machine language, if desired. In either case, the language may be a compiled or interpreted language, and combined with hardware implementations.

[0065] As used herein, the term "computed tomography" is abbreviated as "CT" and refers to both tomographic and non-tomographic radiography. For example, the term "CT" refers to many forms of CT, including, but not limited to, X-ray CT, positron emission tomography (PET), single-photon emission computed tomography (SPECT), and photon-counting computed tomography. Generally, computed tomography (CT) involves the use of an X-ray source and an X-ray detector panel that orbits around the patient, with subsequent reconstruction of images into different planes. In the CT embodiments described herein (e.g., devices, apparatus, methods, and systems provided for CT), the X-ray source is stationary and the patient rotates relative to the stationary source. The X-ray current used in CT describes the flow of current from the cathode to the anode and is typically measured in milliamperes (mA).

[0066] As used herein, the term "structured to [verb]" means that the specified element or assembly has a structure that is shaped, sized, arranged, coupled, and / or configured to perform the specified verb. For example, a member "structured to move" is movably coupled to another element and includes an element that causes the member to move, or the member is configured to move in response to another element or assembly. Thus, as used herein, "structured to [verb]" recites structure, not function. Furthermore, as used herein, "structured to [verb]" means that the specified element or assembly is intended to and designed to perform the specified verb.

[0067] As used herein, the term "associated" means that elements are part of the same assembly and / or work or interact together in some way. For example, a car has four tires and four hubcaps. It is understood that all elements are joined together as part of the car, but each hubcap is "associated" with a particular tire.

[0068] As used herein, the term "coupled" refers to two or more components secured together by any suitable means. Thus, in some embodiments, a statement that two or more parts or components are "coupled" means that the parts are joined or operate together directly or indirectly (e.g., through one or more intermediate parts or components). As used herein, "directly coupled" means that the two elements are in direct contact with each other. As used herein, "fixedly coupled" or "fixed" means that the two components are coupled so that they move as a single component while maintaining a constant orientation relative to each other. Thus, when two elements are coupled, all portions of the elements are coupled. However, a statement that a particular portion of a first element is coupled to a second element (e.g., a first end of an axle is coupled to a first wheel) means that the particular portion of the first element is disposed closer to the second element than the other portions. Furthermore, an object resting on another object held in place only by gravity is not "coupled" to the lower object unless the upper object is otherwise substantially maintained in place. That is, for example, a book on a table is not coupled to the table, but a book glued to the table is coupled to the table.

[0069] As used herein, the terms "removably coupled" or "temporarily coupled" mean that one component is coupled to another component in an essentially temporary manner. That is, the two components are coupled in a manner that allows for easy joining or separation of the components without damaging the components. Thus, "removably coupled" components can be easily uncoupled and recoupled without damaging the components.

[0070] As used herein, the term "operably coupled" means that several elements or assemblies, each movable between a first position and a second position or configuration, are coupled such that movement of the first element from one position / configuration to another position / configuration causes the second element to also move between positions / configurations. Note that a first element is "operably coupled" to another element, not vice versa.

[0071] As used herein, the term "rotatably coupled" refers to two or more components coupled such that at least one of the components is rotatable relative to the other component.

[0072] As used herein, the term "translatably coupled" refers to two or more components coupled such that at least one of the components is translatable relative to the other component.

[0073] As used herein, the term "temporarily disposed" means that a first element or assembly is placed on a second element or assembly such that the first element / assembly can be moved without uncoupling or otherwise manipulating the first element. For example, a book that simply rests on a table (e.g., the book is not glued or secured to the table) is "temporarily disposed" on the table.

[0074] As used herein, the term "corresponding" indicates that two structural components are sized and shaped similarly to one another and are joined with minimal friction. Thus, an opening that "corresponds" to a member is sized slightly larger than the member so that the member can pass through the opening with minimal friction. This definition is modified when two components fit together "nicely." In that situation, the difference in size of the components is even smaller, increasing the amount of friction. If the elements defining the opening and / or the components inserted into the opening are made from deformable or compressible materials, the opening may even be slightly smaller than the components inserted into the opening. With respect to surfaces, shapes, and lines, two or more "corresponding" surfaces, shapes, or lines generally have the same size, shape, and contour.

[0075] As used herein, a "path of movement" or "path," when used in connection with a moving element, includes the space the element travels through during movement. Thus, any moving element inherently has a "path of movement" or "path."

[0076] As used herein, the statement that two or more parts or components "engage" one another means that the elements exert a force or bias on one another, either directly or through one or more intermediate elements or components. Additionally, when used herein with respect to a moving part, the moving part may "engage" another element while moving from one position to another and / or may "engage" another element once it is in the described position. Thus, the statements "element A engages element B when element A moves to element A's first position" and "element A engages element B when element A is in element A's first position" are understood to be equivalent statements and mean that element A engages element B when moving to element A's first position and / or that element A engages element B when element A is in element A's first position.

[0077] As used herein, the term "operably engage" means "engage and move." That is, when used with respect to a first component structured to move a second, movable or rotatable component, "operably engage" means that the first component applies a force sufficient to move the second component. For example, a screwdriver is placed in contact with a screw. When no force is applied to the screwdriver, the screwdriver is simply "coupled" to the screw. When an axial force is applied to the screwdriver, the screwdriver presses against the screw and "engages" it. However, when a rotational force is applied to the screwdriver, the screwdriver "operably engages" the screw and rotates it. Furthermore, with respect to electronic components, "operably coupled" means that one component controls another component via a control signal or current.

[0078] As used herein, the term "number" means one or an integer greater than one (eg, multiple).

[0079] As used herein, in the phrase "[x] moves between its first and second positions," or "[y] is structured to move [x] between its first and second positions," "[x]" is the name of an element or assembly. Furthermore, when [x] is an element or assembly that moves between positions, the pronoun "the" refers to "[x]," i.e., the named element or assembly that precedes the pronoun "the."

[0080] As used herein, the "radial sides / surfaces" of a circular or cylindrical body are those sides / surfaces that extend around or surround its center or a height line passing through its center. As used herein, the "axial sides / surfaces" of a circular or cylindrical body are those sides that extend in a plane that extends generally perpendicular to a height line passing through its center. That is, generally, for a cylindrical soup can, the "radial sides / surfaces" are the generally circular sidewalls and the "axial sides / surfaces" are the top and bottom of the soup can.

[0081] As used herein, a "diagnostic" test includes detecting or identifying a disease state or condition in a subject, determining the likelihood that a subject will suffer from a particular disease or condition, determining the likelihood that a subject with a disease or condition will respond to treatment, determining the prognosis (or likelihood of progression or regression) of a subject with a disease or condition, and determining the effectiveness of a treatment for a subject with a disease or condition. For example, diagnostics can be used to detect the presence or likelihood that a subject has cancer, or the likelihood that such a subject will respond successfully to a compound (e.g., an agent, e.g., a drug) or other treatment.

[0082] As used herein, the term "symptom" generally refers to an illness, disease, injury, event, or change in health status.

[0083] As used herein, the term "treating" or "treatment," with respect to a condition, refers to preventing the condition, reducing the onset or incidence of the condition, reducing the risk of developing the condition, preventing or delaying the onset of symptoms associated with the condition, alleviating or terminating symptoms associated with the condition, causing complete or partial regression of the condition, or some combination thereof. In some embodiments, "treatment" includes exposing the patient or a portion thereof (e.g., a tissue, organ, site, or other localized region of the patient's body) to radiation (e.g., electromagnetic radiation, ionizing radiation).

[0084] As used herein, the term "beam" refers to a stream of radiation (e.g., electromagnetic waves and / or particle radiation). In some embodiments, the beam is produced by a line source and is confined to a small solid angle. In some embodiments, the beam is collimated. In some embodiments, the beam is a generally unidirectional beam. In some embodiments, the beam is a diverging beam.

[0085] As used herein, the term "patient" or "subject" refers to a mammalian animal identified and / or selected for imaging and / or treatment with radiation. Thus, in some embodiments, the patient or subject is contacted with a beam of radiation, e.g., a primary beam produced by a radiation source. In some embodiments, the patient or subject is a human. In some embodiments, the patient or subject is a veterinary or livestock animal, a domestic animal or pet, or an animal used in clinical research. In some embodiments, the subject or patient has cancer and / or is recognized to have or be at risk for cancer.

[0086] As used herein, the term "treatment volume" or "imaging volume" refers to a volume (e.g., tissue) of a patient selected for imaging and / or treatment with radiation. For example, in some embodiments, a "treatment volume" or "imaging volume" includes a tumor in a cancer patient. As used herein, the term "healthy tissue" refers to a volume (e.g., tissue) of a patient that is not and / or does not include the treatment volume. In some embodiments, the imaging volume is larger than the treatment volume and includes the treatment volume.

[0087] As used herein, the term "radiation source" or "ray source" refers to a device that produces radiation (e.g., ionizing radiation) in the form of photons (e.g., described as particles or waves). In some embodiments, the radiation source is a linear accelerator ("linac") that produces x-rays or electrons to treat cancer patients by contacting tumors with the x-ray or electron beam. In some embodiments, the radiation source produces particles (e.g., photons, electrons, neutrons, hadrons, ions (e.g., protons, carbon ions, other heavy ions)). In some embodiments, the radiation source generates electromagnetic waves (e.g., x-rays and gamma rays having wavelengths ranging from about 1 pm to about 1 nm). It is understood that radiation can be described as having both wave-like and particle-like aspects, although it is sometimes convenient to refer to radiation in terms of waves and sometimes in terms of particles. Thus, without limiting the art, both descriptions are used throughout, with the understanding that the laws of quantum mechanics provide that all particles or quantum entities can be described as particles or waves.

[0088] As used herein, the term "radiation dose" refers to the amount of radiation energy deposited per unit mass provided by a radiation beam produced by a radiation source, and may also refer to the characteristics of the radiation beam that provides the radiation. Thus, as used herein, the term "radiation dose" may be characterized by a number of radiation dose characteristics, including, but not limited to, radiation intensity, radiation spectral intensity, radiation dose flux (e.g., instantaneous or average rate of radiation intensity over time), cumulative radiation dose (e.g., integrated amount of radiation dose provided over a period of time), radiation dose symmetry, radiation dose profile shape, radiation dose penumbra, and / or radiation dose distribution. The term "radiation dose" may also be characterized in terms of the variability of the radiation dose characteristic and / or the measurement error associated with measuring the radiation dose characteristic.

[0089] As used herein, the term "stationary source" refers to a source that does not orbit around a patient during use for imaging or therapy. In particular, a "stationary source" remains fixed with respect to an axis that passes through the patient while the patient is being imaged or treated. To create a relative motion between the stationary source and the rotating patient equivalent to the relative motion of a source orbiting around the stationary patient, the patient can rotate about an axis; however, the stationary source does not move with respect to a third object, frame of reference (e.g., the treatment room in which the patient is positioned), or patient axis of rotation during imaging or treatment, whereas the patient rotates with respect to a third object, frame of reference (e.g., the treatment room in which the patient is positioned), or patient axis of rotation that passes through the patient during imaging or treatment. Thus, a stationary source is mounted on a mobile platform, and thus, as the mobile platform moves to transport the stationary source, the stationary source may move with respect to the Earth and any fixed objects on the Earth. Thus, the term "stationary source" can refer to a mobile "stationary source." However, this moving "stationary source" does not orbit around an axis of rotation through the patient during patient imaging or treatment. Furthermore, the stationary source may translate and / or orbit around the patient to position the stationary source before or after patient imaging or treatment. Thus, the term "stationary source" may refer to a source that translates or orbits around the patient in non-imaging and non-treatment uses, for example, to position the source relative to the patient when the patient is not being imaged and / or treated. In some embodiments, the "stationary source" is a photon source and is therefore referred to as a "stationary photon source." In some embodiments, the "stationary source" is a particle source and is therefore referred to as a "stationary particle source."

[0090] As used herein, the term "Z" refers to the atomic number (e.g., of an element and / or of a substance that comprises an element). As used herein, the "Z" of a substance refers to the atomic number of one or more elements from which the substance is made.

[0091] As used herein, "effective atomic number" or "Z eff The term "" refers to the effective or average atomic number of a compound or mixture of substances (e.g., an alloy). eff is determined experimentally or by Murty (1965) "Effective Atomic Numbers of Heterogeneous Materials" Nature 207(4995):398-99, Taylor (2008) "The effective atomic number of dosimetric gels" Australasian Physics&Engineering Sciences in Medicine 31(2):131-38, Taylor (2009) "Electron Interaction with Gel Dosimeters: Effective Atomic Numbers for Collisional,Radiative and Total Interaction Processes” Radiation Research 171(1):123-26, Taylor (2011) “Robust determination of effective atomic numbers for electron interactions with TLD-100 and TLD-100H thermoluminescent dosimeters” Nuclear Instruments and Methods in Physics Research Section B:Beam Interactions with Materials and Atoms 269(8):770-73, and Taylor (2012) “Robust calculation of effective atomic numbers: The Auto-Z eff "Auto-Z software" by Taylor, "Medical Physics 39(4):1769-78, each of which is incorporated herein by reference. eff The software calculates the Z of a compound or mixture of substances. effis freely available to calculate

[0092] As used herein, the term "solid water-equivalent material" refers to a material that has properties similar to water with respect to interacting with an X-ray beam and transporting (e.g., propagating) radiation through the material. In some embodiments, the "solid water-equivalent material" is a plastic. In some embodiments, the solid water-equivalent material has a density of about 0.90 to 1.20 g / cm 3(e.g., 0.90, 0.91, 0.92, 0.93, 0.94, 0.95, 0.96, 0.97, 0.98, 0.99, 1.00, 1.01, 1.02, 1.03, 1.04, 1.05, 1.06, 1.07, 1.08, 1.09, 1.10, 1.11, 1.12, 1.13, 1.14, 1.15, 1.16, 1.17, 1.18, 1.19, or 1.20). In some embodiments, the solid water equivalent material has a viscosity of 5.20 to 6.70 (e.g., 5.20, 5.21, 5.22, 5.23, 5.24, 5.25, 5.26, 5.27, 5.28, 5.29, 5.30, 5.31, 5.32, 5.33, 5.34, 5.35, 5.36, 5.37, 5.38, 5.39, 5.40, 5.41, 5.42, 5.43, 5.44, 5.45, 5.46, 5.47, 5.48, 5.49, 5.50, 5.51, 5.52, 5.53, 5.54, 5.55, 5.56, 5.57, 5.58, 5.59, 5.60, 5.61, 5.62, 5.63, 5.64, 5.65, 5.66, 5.67, 5.68, 5.69, 5.70, 5.71, 5.72, 5.73, 5.74, 5.75, 5.76, 5.77, 5.78, 5.79, 5.80, 5.81, 5.82, 5.83, 5.84, 5.85, 5.86, 5.87, 5.88, 5.89, 5.90, 5.91, 5.92, 5.93, 5.94, 5.95, 5.96, 5.97, 5.98, 5.99, .53, 5.54, 5.55, 5.56, 5.57, 5.58, 5.59, 5.60, 5.61, 5.62, 5.63, 5.64, 5.65, 5.66, 5.67, 5.68, 5.69, 5.70, 5.71, 5.72, 5.73, 5.74, 5.75, 5.76, 5.77, 5.78, 5.79, 5.80, 5.81, 5.82, 5.83, 5.84, 5.85, 5.86, 5.87, 5.88, 5.89, 5.90, 5.91, 5.92, 5.93, 5.94, 5.95, 5.96, 5.97, 5.98, 5.99, 5.100, 5.101, 5.102, 5.103, 5.104, 5.105, 5.106, 5.107, 5.108, 5.109, 5.110, 5.111, 5.112, 5.113, 5.114, 5.115, 5.116, 5.117, 5.118, 5.119, 5.120, 5.121, 5.122, 5.123, 5.124, 5.125, 5.126, 5.127, 5.128, 5.129, 5.130, 5.131, 5.132 3, 5.94, 5.95, 5.96, 5.97, 5.98, 5.99, 6.00, 6.01, 6.02, 6.03, 6.04, 6.05, 6.06, 6.07, 6.08, 6.09, 6.10, 6.11, 6.12, 6.13, 6.14, 6.15, 6.16, 6.17, 6.18, 6.19, 6.20, 6.21, 6.22, 6.23, 6.24, 6.25, 6.26, 6.27, 6.28, 6.29, 6.30, 6.31, 6.32, 6.33, 6.34, 6.35, 6.36, 6.37, 6.38, 6.39, 6.40, 6.41, 6.42, 6.43, 6.44, 6.45, 6.46, 6.47, 6.48, 6.49, 6.50, 6.51, 6.52, 6.53, 6.54, 6.55, 6.56, 6.57, 6.58, 6.59, 6.60, 6.61, 6.62, 6.63, 6.64, 6.65, 6.66, 6.67, 6.68, 6.69, or 6.70).See, e.g., Section 4.2.3 and Table 6 of "Absorbed Dose Determination in External Beam Radiotherapy: An International Code of Practice for Dosimetry Based on Standards of Absorbed Dose to Water," Technical Reports Series No. 398, International Atomic Energy Agency, Vienna, 2000 (incorporated herein by reference). Exemplary, but non-limiting, materials that are solid water equivalents include polystyrene and poly(methyl methacrylate). Table 6 of "Absorbed Dose Determination in External Beam Radiotherapy: An International Code of Practice for Dosimetry Based on Standards of Absorbed Dose to Water," Technical Reports Series No. 398, International Atomic Energy Agency, Vienna, 2000 (incorporated herein by reference) lists the properties of "Solid Water WT1," "Solid Water RMI-457," "Plastic Water," and "Virtual Water." See also "Tissue Substitutes in Radiation Dosimetry and Measurement" (1989) INTERNATIONAL COMMISSION ON RADIATION UNITS AND MEASUREMENTS, Rep. 44, ICRU, Bethesda, Maryland, and Agostinelli (1992) "A new water-equivalent plastic for dosimetry calibration" Med. Phys. 19:774, each of which is incorporated herein by reference.

[0093] As used herein, the term "attenuation coefficient" or "linear attenuation coefficient" refers to a measure of the degree to which the radiative flux of a beam is reduced when passing through a particular material, for example, as a result of absorption and / or scattering. The "mass attenuation coefficient" of a material may be used, in which the attenuation coefficient is normalized per unit density of the material, thus providing a constant value for a given element or compound.

[0094] As used herein, the term "radiation transparent" refers to a material that does not perturb (e.g., substantially and / or virtually does not perturb) measurements when replaced with another material (e.g., air or water) in the beam. For example, air is radiolucent relative to a vacuum, and acrylic is radiolucent as a water wall. If the acrylic were replaced with water, the measurements would be the same because the accumulation and attenuation from the acrylic wall would not be sufficiently different from the water it contains to significantly alter the measurement, provided a correction for mass attenuation is applied.

[0095] As used herein, and when used in reference to the communication of data or signals, "communicating electronically" includes both hardline and wireless forms of communication.

[0096] As used herein, "in electrical communication" means that an electric current passes or can pass between the identified elements. "In electrical communication" further depends on the location or configuration of the elements. For example, in a circuit breaker, a movable contact "is in electrical communication" with a fixed contact when the contacts are in a closed position. The same movable contact "is not in electrical communication" with the fixed contact when the contacts are in an open position. The term "in direct electrical communication" means that two elements are in electrical communication with each other without any intervening element other than a wire, cable, or other conductor connecting the two elements.

[0097] As used herein, the term "computer" generally includes multiple electrical and electronic components that provide power, operational control, and protection to components and modules within a system. For example, a computer may include, among other things, a processing unit (e.g., a microprocessor, microcontroller, or other suitable programmable device), memory, an input unit, and an output unit. The processing unit may include, among other things, a control unit, an arithmetic logic unit ("ALC"), and multiple registers, and may be implemented using known computer architectures (e.g., modified Harvard architecture, von Neumann architecture, etc.). "Microprocessor" or "processor" refers to one or more microprocessors that can be configured to communicate in standalone and / or distributed environments and that can be configured to communicate with other processors via wired or wireless communications, and such one or more processors can be configured to operate on devices controlled by one or more processors, which can be similar or different devices.

[0098] The term "memory," as used herein, generally refers to any memory storage of a computer and is a non-transitory computer-readable medium. Memory may include, for example, a program storage area and a data storage area. The program storage area and data storage area may include a combination of different types of memory, such as ROM, RAM (e.g., DRAM, SDRAM, etc.), EEPROM, flash memory, a hard disk, an SD card, or other suitable magnetic, optical, physical, or electronic memory devices. A processing unit is connected to the memory and can execute software instructions that may be stored in the RAM of the memory (e.g., during execution), in the ROM of the memory (e.g., generally on a persistent basis), or in other memory or another non-transitory computer-readable medium such as a disk. "Memory" may include one or more processor-readable and accessible memory elements and / or components that are internal to a processor-controlled device, external to the processor-controlled device, and accessible via a wired or wired network. Software included in implementations of the methods disclosed herein may be stored in the memory. Software includes, for example, firmware, one or more applications, program data, filters, rules, one or more program modules, and other executable instructions. For example, a computer can be configured to retrieve from memory and execute instructions related to the processes and methods described herein, among other things.

[0099] Medical Radiation Systems In some embodiments, the technology relates to aligning components of a medical radiation system. In some embodiments, the technology relates to a medical radiation system 100, for example, as shown in FIGS. 1A through 1F. In some embodiments, the medical radiation system 100 comprises a patient rotation system 110 structured to rotate about an axis of rotation. In some embodiments, the patient rotation system 110 comprises a patient positioning system (e.g., comprising a patient positioning device or a configurable patient support assembly 120) mounted to a base 130. The base 130 is structured to rotate about an axis 131 of the base 130. In some embodiments, the base 130 is structured to rotate about a vertical axis of symmetry of the base 130. In some embodiments, the patient positioning system, the patient positioning device, and / or the configurable patient support 120 are described in U.S. Patent Application Publication No. 20200268327 and U.S. Patent Application No. 63 / 237,513, each of which is incorporated herein by reference.

[0100] The patient support assembly 120 is structured to support the patient 140 in an upright (e.g., standing, sitting, kneeling, perched) position during radiation treatment or imaging. Thus, in embodiments, the configurable patient support assembly 120 is adjustable to support the patient 140 in an upright (e.g., standing, sitting, kneeling, perched) position or any other position in which the torso of the patient 140 is in a generally vertical or upright position (e.g., semi-standing position, crouching position). In some embodiments, the patient support assembly 120 comprises support members such as a seat, backrest, headrest, armrests, shin rest, heel stops, foot braces, and / or footrests to help support and / or immobilize the patient 140 in a given position. In some embodiments, the configurable patient support assembly 120 comprises one or more configurable and movable components, such as a backrest (e.g., a configurable and movable backrest), a headrest (e.g., a configurable and movable headrest), an armrest (e.g., a configurable and movable armrest), a seat member (e.g., a configurable and movable seat member), a thin rest (e.g., a configurable and movable thin rest), a heel stop (e.g., a configurable and movable heel stop), and / or a foot brace (e.g., a configurable and movable foot brace), as described, for example, in U.S. Patent Application No. 63 / 237,513 (incorporated herein by reference).In some embodiments, one or more configurable, movable components of the configurable patient support comprise one or more powered components, such as a powered backrest (e.g., a backrest operably engaged with a backrest motor), a powered headrest (e.g., a headrest operably engaged with a headrest motor), a powered armrest (e.g., an armrest operably engaged with an armrest motor), a powered seat member (e.g., a seat member operably engaged with a seat member motor), a powered thinrest (e.g., a thinrest operably engaged with a thinrest motor), a powered heel stop (e.g., a heel stop operably engaged with a heel stop motor), and / or a powered foot brace (e.g., a foot brace operably engaged with a foot brace motor). In some embodiments, the backrest motor is structured to move (e.g., translate and / or rotate) the backrest, the headrest motor is structured to move (e.g., translate and / or rotate) the headrest, the armrest motor is structured to move (e.g., translate and / or rotate) the armrest, the seat member motor is structured to move (e.g., translate and / or rotate) the seam member, the thinrest motor is structured to move (e.g., translate and / or rotate) the thinrest, the heelstop motor is structured to move (e.g., translate and / or rotate) the heelstop, and / or the foot brace motor is structured to move (e.g., translate and / or rotate) the foot brace. In some embodiments, the present technology provides a configurable patient support 120 configured in a static configuration. In some embodiments, the present technology provides a configurable patient support 120 configured in a dynamic configuration (e.g., a configuration that moves to assist with patient movement, such as patient entry and / or patient exit). See U.S. Patent Application No. 63 / 237,513, which is incorporated herein by reference.

[0101] In some embodiments, the patient support assembly 120 is operably coupled to the base 130 such that the patient support assembly 120 rotates therewith (e.g., about axis 131). However, the patient support assembly 120 may be adjustably mounted to the base 130 to adjust the position and / or orientation of the patient support assembly 120 relative to the base 130. In some embodiments, the patient support assembly 120 is configured for movement with six degrees of freedom, allowing translation in three perpendicular axes (e.g., two axes in a horizontal plane and a vertical axis) and rotation about three perpendicular axes (e.g., yaw, pitch, and roll). See U.S. Patent Application No. 63 / 237,513, which is incorporated herein by reference. In some embodiments, the patient support assembly 120 is movable with fewer than six degrees of freedom.

[0102] In some embodiments, the medical radiation system 100 comprises a first radiation source 150 configured to generate a beam 151 of electromagnetic radiation. In some embodiments, the first radiation source 150 is a kilovoltage (kV) or megavoltage (MV) X-ray radiation source. The first radiation source 150 can be a therapeutic radiation source or an imaging radiation source. In some embodiments, the medical radiation system further comprises a second radiation source 152 structured to generate a second beam 153 of electromagnetic radiation. Thus, in some embodiments, the medical radiation system 100 comprises two radiation sources, e.g., the first radiation source is a therapeutic radiation source and the second radiation source is an imaging radiation source. In some embodiments, the radiation source 150 is a stationary source, e.g., a source that cannot move during normal operation (e.g., during radiation therapy). Thus, the radiation source 150 may translate, orbit, and / or rotate during a calibration or alignment procedure. In some embodiments, first radiation source 150 is a stationary source and / or second radiation source 152 is a stationary source. Thus, first radiation source 150 and / or second radiation source 152 may translate, orbit, and / or rotate during a calibration or alignment procedure.

[0103] Furthermore, in embodiments, radiation beam 151 from first radiation source 150 is perpendicular to rotation axis 131 of base 130 (e.g., after an alignment procedure), and / or radiation beam 153 from second radiation source 152 is perpendicular to rotation axis 131 of base 130 (e.g., after an alignment procedure). In some embodiments, radiation source 150 is oriented such that radiation beam 151 intersects rotation axis 131. In some embodiments, an isocenter of the radiation beam intersects rotation axis 131.

[0104] In some embodiments, the radiation source 150 is structured to direct the radiation beam 151 towards the patient support assembly 120. Thus, when the patient 140 is positioned on the patient support assembly 120, the radiation source 150 is structured to direct the radiation beam 151 towards the patient 140. In some embodiments, the medical radiation system 100 includes a detector 160 (e.g., a detection panel) disposed opposite the radiation source 150 to detect the radiation beam 151 traversing the patient 140. In some embodiments, the detector 160 is an imaging device that produces signals and / or data for generating an image produced by the radiation beam 151. In some embodiments, an additional (e.g., second) detector 162 is associated with the second radiation source 152 of the medical radiation system 100. In some embodiments, for example, as further described herein, a phantom 170 (e.g., a water phantom comprising a tank, liquid, and a detector, or a solid phantom comprising a solid water-equivalent material (e.g., as shown in FIGS. 3-5 )) is placed between the radiation source 150 and the detector 160 (e.g., a detection panel). In some embodiments, for example, as further described herein, a phantom 170 (e.g., a water phantom comprising a tank, liquid, and a detector, or a solid phantom comprising a solid water-equivalent material (e.g., as shown in FIGS. 3-5 )) is placed between the second radiation source 152 and the second detector 162 (e.g., a detection panel). Those skilled in the art will understand that a medical radiation system comprises a detector, a phantom as described herein comprises a detector, and these two detectors are different components of the present technology.The detector of the medical radiation system (e.g., detector 160) is located on the opposite side of the source (e.g., radiation source 150), for example, so that the detector and source of the medical radiation system are located on either side of a patient being positioned for imaging and / or treatment by the medical radiation system; the detector of the phantom is present, for example, within a tank of the water phantom or within a solid phantom (e.g., within a hole in the solid phantom) so that the detector of the phantom can be located at or near the location of the medical radiation system where the patient would otherwise be located (e.g., on a patient support assembly).

[0105] phantom The present technology relates to phantoms for use in quality assurance verification of medical radiation systems. In some embodiments, the phantom is a water phantom. In some embodiments, the phantom is a solid phantom. In some embodiments, the water phantom comprises a tank, the tank comprises water, and a detector is placed in the water. The water can also be approximated by a solid material (e.g., plastic). See, for example, section 4.2.3 and Table 6 of "Absorbed Dose Determination in External Beam Radiotherapy: An International Code of Practice for Dosimetry Based on Standards of Absorbed Dose to Water," Technical Reports Series No. 398, International Atomic Energy Agency, Vienna, 2000 (incorporated herein by reference). Thus, in some embodiments, the phantom is a solid phantom comprising a solid water-equivalent material. In some embodiments, the solid water-equivalent material is specific to the particular beam quality or x-ray energy being tested.

[0106] In some embodiments, the solid phantoms described herein provide advantages over phantoms comprising liquids (e.g., liquid water), for example, when measuring radiation dose during acceleration or deceleration of the phantom, or at any time when rotation or movement of the liquid (e.g., liquid water) phantom changes the liquid level (e.g., liquid water level). Thus, in some embodiments, the solid phantom can be rotated to any measurement angle without having to stabilize the phantom material before making measurements.

[0107] The technology provided herein relates to embodiments of phantoms comprising liquid water ("water phantoms") and embodiments of phantoms comprising a solid water equivalent ("solid phantoms").

[0108] In some embodiments, the present technology provides a water phantom. In some embodiments, the water phantom comprises a tank and a liquid held within a volume of the tank. In some embodiments, the liquid is water, a composition comprising water, and / or an aqueous solution. In some embodiments, the tank comprises a base (e.g., a surface of the tank that supports the weight of the liquid contained in the tank (e.g., against gravity acting on the liquid (e.g., water))) and one or more sidewalls that define a volume for containing the liquid (e.g., water, a composition comprising water, and / or an aqueous solution). In some embodiments, the tank has a polygonal (e.g., quadrilateral (e.g., rectangular)) shape when viewed from above. However, the present technology is not limited to tanks having polygonal, quadrilateral, and / or rectangular shapes when viewed from above. Thus, in embodiments, the tank has other shapes when viewed from above, such as, for example, an "L" shape, a cross shape, a circular shape, etc.

[0109] In some embodiments, the side walls of the tank comprise a material that is transparent and / or radiolucent to X-ray radiation. In some embodiments, the side walls of the tank comprise a material (e.g., a radiotransparent or "radiolucent" material) that has a low attenuation coefficient, e.g., a low attenuation coefficient compared to other materials in the beam path. In some embodiments, the side walls of the tank transmit radiation similarly to water, so that measurements are not disturbed by radiation passing through the side walls. In some embodiments, the side walls of the tank comprise a homogeneous material (e.g., a radiotransparent or "radiolucent" material) that has a low attenuation coefficient or an attenuation coefficient similar to that of water or liquid contained in the tank. In some embodiments, a material with a low attenuation coefficient is, for example, poly(methyl methacrylate), also known as acrylic glass and commercially available under the name PERSPEX.

[0110] In some embodiments, the tank comprises a detector. In some embodiments, the detector is fully immersed in the liquid of the tank. In some embodiments, the detector is partially immersed in the liquid of the tank. In some embodiments, the detector is structured to measure the energy, intensity, and / or dose of the radiation beam. In some embodiments, the detector is structured to measure one or more other characteristics of the radiation beam (e.g., shape, spectrum, wavelength, flux, photon count, etc.). In some embodiments, the detector comprises an ion chamber.

[0111] In some embodiments, the detector is movable within the tank. In some embodiments, the detector is mounted on an adjustable arm fixed to the tank such that the location and / or orientation of the detector can be adjusted using the adjustable arm. In some embodiments, the tank comprises multiple detectors (e.g., in some embodiments, the tank comprises two, three, four, five, six, seven, eight, or more detectors). In some embodiments, the tank comprises two detectors oriented at right angles to each other, e.g., such that the radiation beam is detected by both detectors when the tank is rotated 90°. In some embodiments, the tank comprises two detectors oriented at a 180° angle to each other, e.g., such that the radiation beam is detected by both detectors when the tank is rotated 180°. In some embodiments, the detectors are removable from the solid phantom, e.g., for calibration, replacement, maintenance, and / or repair.

[0112] In some embodiments, the tank comprises a single cylindrical detector oriented vertically along the axis of rotation of the tank, for example, so as to present a detection plane at a constant distance from the source (e.g., at a fixed location) along the axis of the radiation beam for all angles of rotation of the tank. In this way, the distance between the radiation source and the detector remains constant as the tank rotates.

[0113] In some embodiments, the detector is movable within the tank and may, for example, measure beam properties at one or more locations within the tank, so that the tank defines a measurement area (or measurement volume).

[0114] In some embodiments, the present technology provides a solid phantom. In some embodiments, the solid phantom comprises a solid water-equivalent material. In some embodiments, the solid water-equivalent material is a material described in "Absorbed Dose Determination in External Beam Radiotherapy: An International Code of Practice for Dosimetry Based on Standards of Absorbed Dose to Water," Technical Reports Series No. 398, International Atomic Energy Agency, Vienna, 2000 (incorporated herein by reference), particularly Section 4.2.3 and / or Table 6 of this reference.

[0115] In some embodiments, the solid phantom comprises several holes. In some embodiments, the solid phantom comprises 1 to 10 holes (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 holes). In some embodiments, the holes are precisely machined (e.g., drilled) into the solid water-equivalent material to securely hold the detector.

[0116] In some embodiments, the solid phantom comprises a base (e.g., a surface of the solid phantom that supports the weight of the solid phantom (e.g., against the force of gravity acting on the solid phantom)) and one or more exterior surfaces that define a volume.

[0117] In some embodiments, the solid phantom has a polygonal (e.g., quadrilateral (e.g., rectangular)) shape when viewed from above. However, the present technology is not limited to solid phantoms having polygonal, quadrilateral, and / or rectangular shapes when viewed from above. Thus, in embodiments, the solid phantom has other shapes when viewed from above, such as, for example, an "L" shape, a cross shape, a circular shape, etc.

[0118] In some embodiments, the solid phantom comprises a detector. In some embodiments, the solid phantom comprises a hole, the hole comprising the detector. In some embodiments, the solid phantom comprises several holes, one or more of the several holes comprising a detector. In some embodiments, the solid phantom comprises 1 to 10 holes (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 holes), and several of the 1 to 10 holes (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10) each comprise a detector. In some embodiments, the detector is removable from the solid phantom, e.g., for calibration, replacement, maintenance, and / or repair. In some embodiments, the hole is precision machined (e.g., drilled) into the solid water-equivalent material to securely hold the detector. In some embodiments, the detector fits securely into a hole provided (e.g., by precision machining) in the solid water-equivalent material of the solid phantom.

[0119] In some embodiments, the detector is configured to measure the energy, intensity, and / or dose of the radiation beam. In some embodiments, the detector is configured to measure one or more other characteristics of the radiation beam (e.g., shape, spectrum, wavelength, flux, photon count, etc.). In some embodiments, the detector comprises an ion chamber.

[0120] In some embodiments, the detector is movable within the solid phantom. In some embodiments, the detector is removable from a first hole in the solid phantom and insertable into a second hole in the solid phantom. In some embodiments, the solid phantom comprises multiple detectors (e.g., in some embodiments, the solid phantom comprises two, three, four, five, six, seven, eight, or more detectors). In some embodiments, the solid phantom comprises multiple detectors, each detector residing within a hole in the multiple holes in the solid phantom.

[0121] In some embodiments, the solid phantom comprises two detectors oriented at right angles to each other, e.g., such that the radiation beam is detected by both detectors when the solid phantom is rotated by 90°. In some embodiments, the solid phantom comprises two detectors oriented at 180° to each other, e.g., such that the radiation beam is detected by both detectors when the solid phantom is rotated by 180°.

[0122] In some embodiments, the solid phantom comprises a single cylindrical detector (e.g., the solid phantom comprises a hole and the detector resides in the hole) oriented vertically along the axis of rotation of the solid phantom so as to present a detection plane at a constant distance from the source (e.g., at a fixed location) along the axis of the radiation beam for all angles of rotation of the solid phantom. In this way, the distance between the radiation source and the detector remains constant as the solid phantom is rotated.

[0123] In some embodiments, the detector is movable within the solid phantom (e.g., the detector is removable from a first hole in the solid phantom and insertable into a second hole in the solid phantom), and the solid phantom defines a measurement area (or measurement volume), e.g., so that beam characteristics can be measured at one or more locations within the solid phantom.

[0124] In some embodiments, the phantom (e.g., a water phantom or a solid phantom) comprises a detector. In some embodiments, the detector comprises an ion chamber. In some embodiments, the detector is structured to detect megavoltage (e.g., treatment) x-ray beams. Without limitation, exemplary detectors for use in embodiments of the present technology include FARMER-type detectors such as EXRADIN A12 and EXRADIN A19 commercially available from Standard Imaging; 30010 or 30012 ionization chambers commercially available from PTW; FC65-G ionization chambers commercially available from Iba Dosimetry; and SNC15c, SNC350p, or SNC600c commercially available from Sun Nuclear. Without limitation, detectors (e.g., ionization chambers) are described in "Absorbed Dose Determination in External Beam Radiotherapy: An International Code of Practice for Dosimetry Based on Standards of Absorbed Dose to Water," Technical Reports Series No. 398, International Atomic Energy Agency, Vienna, 2000 (incorporated herein by reference), particularly Section 4.2.1 and Tables 3 and 4.

[0125] method In some embodiments, for example, as shown in FIG. 2, the present technology provides a method for measuring a radiation dose provided by a medical radiation system including a patient rotation system and a radiation source (e.g., a stationary source). For example, in some embodiments, the method 200 includes placing 210 a phantom (e.g., a water phantom including a tank, water, and a detector; or a solid phantom including a solid water-equivalent material and a detector) on a patient support assembly of the patient rotation system. In some embodiments, the method includes using a phantom system including a phantom (including a detector), an electrometer, and a slip ring, for example, as shown in FIGS. 5A and 5B. Thus, in some embodiments, the method includes providing a phantom system including a phantom (including a detector), an electrometer, and a slip ring, for example, as shown in FIGS. 5A and 5B.

[0126] Additionally, in some embodiments, the method includes moving 220 the phantom relative to the radiation beam generated by the radiation source. In some embodiments, the method includes detecting 230 the radiation beam. In some embodiments, the method includes calculating 240 a radiation dose of the radiation beam.

[0127] In some embodiments, method 200 is used to measure radiation dose in a medical radiation system that includes a patient rotation system configured to rotate about an axis of rotation. For example, radiation therapy system 100 as shown in FIG. 1 is one example of such a medical radiation system. However, embodiments of method 200 are not limited to use with radiation therapy system 100 described herein. Thus, in embodiments, method 200 is used to measure radiation dose in any medical radiation system (e.g., any radiation therapy system and / or any medical imaging system).

[0128] In some embodiments, placing 210 the phantom (e.g., a water phantom comprising a tank, water, and a detector; or a solid phantom comprising a solid water-equivalent material and a detector) on the patient support assembly includes attaching or mounting the phantom to a component of the patient support assembly. In some embodiments, the phantom is attached to a seat member of the patient support assembly. In some embodiments, the phantom is mounted to one or more armrests of the patient support assembly. For example, in embodiments, the phantom may be mounted to one or more armrests using an interface configured to hold quality assurance equipment. In some embodiments, the phantom is secured to any other part or component of the patient support assembly. For example, in embodiments, the phantom is secured to a part or component generally structured to support or secure a patient. In some embodiments, the phantom system comprises a phantom (with a detector), an electrometer, and a slip ring, as shown, for example, in FIGS. 5A and 5B.

[0129] In some embodiments, a phantom (e.g., a water phantom comprising a tank, water, and a detector; or a solid phantom comprising a solid water-equivalent material and a detector) is placed on the patient support assembly such that the axis of rotation passes through the phantom and / or passes through the interior volume of the phantom. In some embodiments, the geometric center of the phantom is aligned with the axis of rotation. In some embodiments, the geometric center of the phantom is aligned with the isocenter of the medical radiation system. In some embodiments, method 200 further includes aligning the geometric center of the phantom with the axis of rotation. In some embodiments, the phantom is supported by a seat member of the patient support assembly, and the phantom is aligned using an armrest of the patient support assembly. That is, in some embodiments, the seat member of the patient support assembly is used to support the weight of the phantom, while the armrest of the patient support assembly is used to align the phantom.

[0130] In some embodiments, a phantom (e.g., a water phantom comprising a tank, water, and a detector; or a solid phantom comprising a solid water-equivalent material and a detector) is placed on a horizontal surface (e.g., on a sheet member) of a patient support assembly. In some embodiments, the rotation axis is a vertical axis (e.g., a substantially and / or effectively vertical axis), and the rotation axis extends along the vertical dimension of the phantom. In some embodiments, the rotation axis is perpendicular (e.g., substantially and / or effectively vertical) to the radiation beam. Thus, in some embodiments, the radiation beam travels (e.g., substantially and / or effectively) along a horizontal plane orthogonal (e.g., substantially and / or effectively orthogonal) to the vertical rotation axis. In some embodiments, the phantom is disposed horizontally on the patient support assembly such that the central axis of the radiation beam is parallel (e.g., substantially and / or effectively parallel) to the base of the phantom. In some embodiments, the base of the phantom is defined as the surface of the tank that supports the weight of the phantom (e.g., against gravity acting on the phantom).

[0131] In some embodiments, a phantom (e.g., a water phantom comprising a tank, water, and a detector; or a solid phantom comprising a solid water-equivalent material and a detector) is placed on the patient support assembly so that a side wall or exterior surface of the phantom faces the radiation source and the radiation beam passes through the side wall or exterior surface and enters the phantom. In some embodiments, the location and orientation of the phantom is such that the side wall or exterior surface facing the radiation source is perpendicular to the central axis of the radiation beam.

[0132] In some embodiments, moving 220 the phantom (e.g., a water phantom comprising a tank, water, and a detector; or a solid phantom comprising a solid water-equivalent material and a detector) includes rotating the phantom, for example, by rotating a patient rotation system about an axis of rotation. In some embodiments, moving 220 the phantom includes translating the phantom, for example, by translating a patient support assembly relative to the patient rotation system. In some embodiments, moving 220 the phantom includes moving the patient support assembly relative to the patient rotation system (e.g., without shifting the axis of rotation of the patient rotation system). For example, in some embodiments, the patient support assembly is adapted for rotational movement (e.g., yaw, pitch, and / or roll) relative to a base of the patient rotation system. In some embodiments, moving the phantom includes moving the patient rotation system relative to a fixed radiation source (e.g., without shifting the axis of rotation of the patient rotation system). For example, in some embodiments, the patient rotation system is mounted on a translatable member (e.g., movable vertically or in any other direction), thus allowing the entire patient rotation system to translate in space. In some embodiments, rotating the phantom also includes rotating the phantom, the electrometer, and the cable. In some embodiments, rotating the phantom also includes rotating a first component on the phantom side of the slip ring. See Figures 5A and 5B.

[0133] In some embodiments, the phantom (e.g., a water phantom comprising a tank, water, and a detector; or a solid phantom comprising a solid water-equivalent material and a detector) is rotated in a continuous cycle. In some embodiments, the phantom is rotated in a discontinuous cycle. For example, in some embodiments, the phantom is rotated 90°, after which the radiation beam is detected (230) and the radiation dose of the radiation beam is calculated (240) before the phantom rotation is resumed. In some embodiments, the phantom is rotated through any angle (e.g., 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 310, 320, 330, 340, or 350 degrees) and then detecting (230) the radiation beam. , calculate the radiation dose of the radiation beam (240) and then resume rotating the phantom any angle (e.g., 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 310, 320, 330, 340, or 350°). In some embodiments, the method includes waiting a period of time after the step of rotating the phantom (e.g., a water phantom) is completed, e.g., after the rotation has stopped and the phantom has come to rest, e.g., to allow the liquid (e.g., water) to stop moving, e.g., to allow the liquid (e.g., water) to stabilize and thus minimize and / or eliminate fluctuations in the level of the liquid (e.g., water).

[0134] Alternatively, in some embodiments, the phantom is rotated continuously (e.g., without interrupting rotation) while detecting 230 the radiation beam and / or calculating 240 the radiation dose of the radiation beam. In some embodiments, the method includes detecting 230 the radiation beam while moving 220 (e.g., rotating and / or translating) the phantom, or detecting 230 the radiation beam within the relaxation time requirements of the liquid. Accordingly, in some embodiments, the method includes providing and / or using a solid phantom. The solid phantom embodiments described herein offer advantages over water phantoms for detecting the radiation beam while the phantom is rotating because the solid water-equivalent material of a solid phantom remains at a constant level during rotation, while the water level in a water phantom can fluctuate during rotation due to the acceleration of the phantom and the water in the phantom tank.

[0135] In some embodiments, detecting the radiation beam (230) includes detecting the radiation beam using a detector placed within a phantom (e.g., a water phantom comprising a tank, water, and a detector; or a solid phantom comprising a solid water-equivalent material and a detector). In some embodiments relating to a water phantom, the detector is fully immersed in the liquid of the tank. In some embodiments relating to a water phantom, the detector is partially immersed in the liquid of the tank. In some embodiments, detecting the radiation beam includes measuring the dose of the radiation beam. In some embodiments, the energy (e.g., average energy) and / or intensity of the radiation beam is calculated from one or more dose measurements.

[0136] Thus, in some embodiments, the detector is structured to measure the dose of the radiation beam, hi some embodiments, the detector is structured to measure one or more other characteristics of the radiation beam (e.g., the dose profile).

[0137] In some embodiments, the detector is movable within the phantom (e.g., a water phantom comprising a tank, water, and a detector; or a solid phantom comprising a solid water-equivalent material and a detector). In some embodiments related to a water phantom, the detector is mounted on an adjustable arm fixed to the tank such that the adjustable arm can be used to adjust the location and / or orientation of the detector. In some embodiments related to a solid phantom, the detector can be moved between multiple holes (e.g., removed from a first hole and inserted into a second hole). In some embodiments, detecting the radiation beam includes positioning the detector to intercept the radiation beam by moving the phantom and / or moving the detector within the phantom. The radiation beam spreads in space as it travels (e.g., due to divergence and / or scattering); therefore, in some embodiments, detecting the radiation beam includes detecting the radiation beam at multiple locations within the phantom to detect multiple rays of the beam as the rays diverge.

[0138] In some embodiments, multiple detectors are provided within the phantom to detect the radiation beam as the phantom rotates (e.g., two, three, four, five, six, seven, or eight detectors are provided within the phantom to detect the radiation beam as the phantom rotates). In some embodiments, two detectors are oriented perpendicular to each other so that the radiation beam is detected when the phantom is rotated 90°. In some embodiments, two detectors are oriented opposite each other so that the radiation beam is detected when the phantom is rotated 180°. In some embodiments, a single cylindrical detector is oriented perpendicular to the axis of rotation so as to present a detection plane at a constant distance from the source (e.g., at a fixed location) along the axis of the radiation beam for all angles of rotation of the phantom. In this way, the distance between the radiation source and the detector remains constant as the phantom is rotated.

[0139] In some embodiments, calculating 240 the radiation dose of the radiation beam includes combining multiple measurements of the radiation beam from the detector. In some embodiments, calculating the radiation dose of the radiation beam includes generating a spatial profile (e.g., a two-dimensional or three-dimensional profile) of the intensity of the radiation beam within the phantom. In some embodiments, the detector is movable within the phantom and can, for example, measure beam characteristics at one or more locations within the phantom, such that the phantom defines a measurement area (or measurement volume).

[0140] Dose scanning system and method In some embodiments, for example, as shown in FIG. 3 , the present technology provides a system for performing dose scans, e.g., full three-dimensional (3D) dose scans. In some embodiments, the dose scans are used to measure dose distributions, commission linear accelerators (linacs), and / or perform quality assurance and / or maintenance processes for medical radiation systems. In some embodiments, the dose scans provide characterization of the three-dimensional intensity profile of the radiation beam. In embodiments, scans are performed for a range of beam field sizes. In some embodiments, data obtained from these measurements is used to construct a three-dimensional map of the radiation beam.

[0141] In some embodiments, the system includes a phantom 310 (e.g., a water phantom including a tank, water, and a detector; or a solid phantom including a solid water-equivalent material and a detector). In some embodiments, the phantom 310 is placed on a patient support assembly of a patient rotation system structured to rotate about an axis of rotation 320. In some embodiments, the phantom 310 is positioned such that a segment of the axis of rotation 320 lies within a side wall or exterior surface of the phantom 310. That is, in some embodiments, the side wall or exterior surface of the phantom 310 facing the radiation source 350 is parallel (e.g., substantially and / or virtually parallel) to the axis of rotation 320, which passes along the plane of the side wall or exterior surface.

[0142] In the exemplary embodiment shown in FIG. 3, a first beam 330 and a second beam 340 are shown incident on a phantom 310 (e.g., a water phantom comprising a tank, water, and a detector; or a solid phantom comprising a solid water-equivalent material and a detector). As an example, first beam 330 and second beam 340 may have different areas projected onto phantom 310, e.g., as shown in FIG. 3. For example, beam 330 may have dimensions of 10 cm x 10 cm, and beam 340 may have dimensions of 30 cm x 30 cm (e.g., corresponding to the dimensions of the semi-minor and semi-major axes of an ellipse defined by the area of the beams incident on phantom 310). In this example, the length of the larger sidewall or exterior surface of phantom 310 may be 100 cm. The present technology is not limited to phantoms 310 having side walls or exterior surfaces of 100 cm, and / or beams having areas of 10 cm x 10 cm and 30 cm x 30 cm. Thus, the present technology relates to beams and phantoms having any other length or area. In some embodiments, the phantom and radiation source 350 are positioned such that the beam area is contained within the phantom. That is, in embodiments, the dimensions (e.g., height and / or width) of the area of the beam projected onto the phantom do not exceed one or more dimensions (e.g., height and / or width) of the side walls or exterior surfaces of the phantom on which the beam is incident.

[0143] In some embodiments, the first beam 330 and the second beam 340 are generated asynchronously. In some embodiments, the first beam 330 and the second beam 340 are generated simultaneously (e.g., substantially and / or virtually simultaneously). In some embodiments, the first beam 330 and the second beam 340 are generated by the same source. In some embodiments, the first beam 330 and the second beam 340 are generated by different sources (e.g., the first beam 330 is generated by a first source and the second beam 340 is generated by a second source). In some embodiments, a beam shaping system is provided for adjusting the size and / or shape (e.g., in one or two dimensions) of the radiation beam.

[0144] In some embodiments, the system includes a detector (e.g., a water phantom or solid phantom detector). In some embodiments, the detector is placed inside the phantom 310. In some embodiments, the detector is moved within the phantom to obtain a three-dimensional profile of the radiation beam. In some embodiments, the detector is moved along a vertical axis, a horizontal axis, and / or a depth axis to detect beam intensity at multiple points within the phantom 310. In some embodiments, the detector is translated along a vertical axis, a horizontal axis, and / or a depth axis to detect beam intensity at multiple points within the phantom 310. In some embodiments, the detector is rotated (e.g., providing pitch, roll, and / or yaw rotation) along a vertical axis, a horizontal axis, and / or a depth axis to detect beam intensity at multiple points within the phantom 310.

[0145] In some embodiments, the patient support assembly is moved to obtain a three-dimensional profile of the radiation beam. In some embodiments, the patient support assembly is moved along a vertical axis, a horizontal axis, and / or a depth axis to detect beam intensity at multiple points within the phantom 310. In some embodiments, the patient support assembly is translated along a vertical axis, a horizontal axis, and / or a depth axis to detect beam intensity at multiple points within the phantom 310. In some embodiments, the patient support assembly is rotated (e.g., providing pitch, roll, and / or yaw rotation) along a vertical axis, a horizontal axis, and / or a depth axis to detect beam intensity at multiple points within the phantom 310.

[0146] Some embodiments combine moving the detector and moving the patient support assembly to detect beam intensity in three-dimensional space. For example, in some embodiments, the detector is translated along and / or rotated about a vertical, horizontal, and / or depth axis, and the patient support assembly is translated along and / or rotated about a vertical, horizontal, and / or depth axis. As an example, the detector may move in two dimensions (e.g., any two of translation along a vertical axis, translation along a horizontal axis, translation along a depth axis, rotation about a vertical axis, rotation about a horizontal axis, and / or rotation about a depth axis) while the patient support assembly may move in a third dimension (e.g., any one of translation along a vertical axis, translation along a horizontal axis, translation along a depth axis, rotation about a vertical axis, rotation about a horizontal axis, and / or rotation about a depth axis); or, alternatively, the detector may move in one dimension (e.g., any one of translation along a vertical axis, translation along a horizontal axis, translation along a depth axis, rotation about a vertical axis, rotation about a horizontal axis, and / or rotation about a depth axis) while the patient support assembly may move in two dimensions (e.g., any two of translation along a vertical axis, translation along a horizontal axis, translation along a depth axis, rotation about a vertical axis, rotation about a horizontal axis, and / or rotation about a depth axis).

[0147] Tissue phantom dose ratio measurement system and method 4A and 4B, the present technology provides a system for performing tissue phantom dose ratio measurements. In some embodiments, a phantom 410 (e.g., a water phantom comprising a tank, water, and a detector; or a solid phantom comprising a solid water-equivalent material and a detector) is placed on a patient support assembly of a patient rotation system structured to rotate about an axis of rotation 420. In some embodiments, the phantom 410 is positioned so that the axis of rotation 420 intersects the interior volume of the phantom 410 (e.g., the axis of rotation 420 passes through the phantom 410). In some embodiments, a detector is mounted on the axis of rotation 420 within the phantom 410 to detect the radiation beam 430. Thus, in some embodiments, the detector is positioned within the phantom at a location having a distance from the source 440 that is constant (e.g., substantially and / or effectively constant) as the phantom rotates about the axis of rotation.

[0148] 4A shows a phantom 410 in a first orientation in which the beam 430 reaches the detector after traveling a first distance within the phantom 410 (e.g., a water phantom comprising a tank, water, and a detector; or a solid phantom comprising a solid water-equivalent material and a detector). FIG. 4B shows a phantom 410 in a second orientation (e.g., rotated 90° clockwise relative to the first orientation) in which the beam 430 reaches the detector after traveling a second distance within the phantom 410, where the second distance is longer than the first distance. In both the first orientation of the phantom 410 and the second orientation of the phantom 410, the side wall or exterior surface of the phantom 410 facing the radiation source 440 is perpendicular to the central axis of the beam 430. In some embodiments, the phantom is rotated by any other angle between the first and second orientations (e.g., the phantom is rotated by 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 310, 320, 330, 340, or 350 degrees).

[0149] In some embodiments, the beam 430 contacts a detector, and the detector detects the beam 430. Thus, in embodiments, the propagation path length of the beam 430 is defined as the distance traveled by the beam within the phantom 410 (e.g., a water phantom comprising a tank, water, and a detector; or a solid phantom comprising a solid water-equivalent material and a detector). As used herein, the term "propagation path" refers to the linear distance between the side wall or exterior surface of the phantom facing the radiation source 440 and the detector within the phantom. In some embodiments, for example, as shown in FIGS. 4A and 4B, the propagation path length of the beam 430 within the phantom 410 in a first orientation (e.g., 10 cm) is different from the propagation path length of the beam 430 within the phantom 410 in a second orientation (e.g., 20 cm). Method embodiments include measuring dose and / or calculating beam quality (e.g., energy, intensity, flux, attenuation, absorbed dose) using the phantom in a first orientation, measuring dose and / or calculating beam quality (e.g., energy, intensity, flux, attenuation, absorbed dose) using the phantom in a second orientation, and comparing the first measured or calculated quality to the second measured or calculated quality to calculate a tissue-phantom dose ratio (TPR) that characterizes the progression of the beam 430 through the phantom 410. The TPR measurement, which may be responsive to the beam's energy or intensity, is an indicator of the beam's quality.

[0150] In some embodiments, the method comprises TPR 20,10 In some embodiments, the TPR 20,10Calculating ρ includes using an embodiment of a system and / or phantom 410 described herein, e.g., a phantom having dimensions such that the first propagation path length is 10 cm and the second propagation path length is 20 cm (e.g., as shown in FIGS. 4A and 4B ), and a detector placed within the phantom (e.g., a water phantom comprising a tank, water, and a detector; or a solid phantom comprising a solid water-equivalent material and a detector). In some embodiments, the ratio of the measurements at 20 cm and 10 cm provides a measure of the quality of the radiation (e.g., the average energy of the beam).

[0151] This technology is TPR 20,10 4A and 4B (e.g., a water phantom comprising a tank, water, and a detector; or a solid phantom comprising a solid water-equivalent material and a detector). Thus, the present technique can measure other propagation path lengths by changing the dimensions of the phantom 410, using different rotation angles, or changing the location of the detector within the phantom 410.

[0152] In some embodiments, the described techniques provide methods, devices, and systems for measuring X-ray dose and / or calculating the average beam energy or beam quality of an isocentric dose. In some embodiments, the described techniques provide methods, apparatus, and systems for measuring X-ray beam quality and expressing the X-ray beam quality as a tissue phantom dose ratio (TPR). In some embodiments, measuring X-ray beam quality and expressing the X-ray beam quality as a tissue phantom dose ratio (TPR) (e.g., for isocentric dose) involves applying a translational and / or rotational offset of the patient rotation system to measure the beam at different propagation lengths (e.g., 10 cm and 20 cm). The rotational and / or translational movement of the phantom allows different measurements to be made without requiring a technician or other operator to access the medical radiation system or repeatedly reconfigure the measurement setup. In some embodiments, the method enables efficient positioning of a measurement system (e.g., a phantom (e.g., a water phantom comprising a tank, water, and a detector; or a solid phantom comprising a solid water-equivalent material and a detector)) for measuring radiation dose in a medical radiation system. In some embodiments, a microprocessor (e.g., executing instructions provided by software) controls the measurement of beam properties, the movement of the phantom (e.g., translation and / or rotation), and the calculation of the TPR. In some embodiments, the microprocessor outputs the TPR value to a user. In some embodiments, the microprocessor outputs the TPR value to a user after the electrometer processes the signal, and the processed charge signal and / or the processed current signal from the ion chamber are transmitted to the user through slip rings.

[0153] Phantom System In some embodiments, for example, as shown in FIGS. 5A and 5B, the present technology provides a phantom system 500 for measuring radiation dose. In some embodiments, the phantom system 500 comprises a phantom 501 (e.g., a water phantom or a solid phantom) comprising a detector, an electrometer 502, a slip ring 503, and a microprocessor 504. In some embodiments, the microprocessor or computer further comprises the electrometer. In some embodiments, the electrometer has a very high input impedance (e.g., at least about 10 14 The electrometer 502 is a voltmeter and / or ammeter that has a resistance (ohm) and therefore determines very small signals (e.g., less than 1 pC and / or 1 nA). In some embodiments, the electrometer 502 is removable from the phantom system 500, for example, for calibration, replacement, maintenance, and / or repair of the electrometer.

[0154] In some embodiments, the detector of the phantom 501 is in electrical or electronic communication with the electrometer 502. In some embodiments, the detector of the phantom 501 is in electrical or electronic communication with the electrometer 502 through a cable 505 connecting the detector and the electrometer 502. In some embodiments, the cable 505 connecting the detector and the electrometer 502 is a triaxial cable. In some embodiments, the electrometer 502 is in electrical or electronic communication with a microprocessor 504 (e.g., a computer). In some embodiments, the electrometer 502 outputs a signal that is communicated to the microprocessor 504 (e.g., a computer). In some embodiments, the electrometer 502 outputs a signal that is communicated to the microprocessor 504 (e.g., a computer) across a slip ring 503. In some embodiments, the slip ring 503 comprises a first component on the phantom side that rotates with the phantom 501 and the electrometer 502; and a second component on the user side that does not rotate with the phantom 501 and the electrometer 502. A first component on the phantom side of slip ring 503 and a second component on the user side of slip ring 503 are in electrical or electronic communication with each other. In some embodiments, the first component on the phantom side of slip ring 503 is in electrical or electronic communication with electrometer 502 via cable 507; and the second component on the user side of slip ring 503 is in electrical or electronic communication with microprocessor 504 through cable 506. In some embodiments, system 500 further comprises an analog-to-digital converter (ADC) that converts the electrical (e.g., analog) signal produced by electrometer 502 to a digital signal for communication (e.g., across slip ring 503) to microprocessor 504.

[0155] In some embodiments, the method includes placing a phantom 501 of the phantom system 500 (e.g., a water phantom including a tank, water, and a detector; or a solid phantom including a solid water-equivalent material and a detector) on a patient support assembly of the patient rotation system. In some embodiments, the electrometer 502 and cable 505 (e.g., a triaxial cable) of the phantom system 500 are also placed on the patient support assembly of the patient rotation system. In some embodiments, the method includes rotating the patient rotation system about an axis of rotation 590 such that the phantom 501, the electrometer 502, and the cable 505 (e.g., a triaxial cable) of the phantom system 500 rotate about the axis of rotation 590. A first component on the phantom side of the slip ring 503 also rotates about the axis of rotation 590 while remaining in electrical or electronic communication with a second component on the user side of the slip ring 503. During rotation of the patient rotation system about axis of rotation 590 (and thus rotation of phantom 501, electrometer 502, and cable 505 (e.g., triaxial cable)), microprocessor 504 and cable 506 do not rotate about axis of rotation 590. A second component on the user side of slip ring 503 also does not rotate about axis of rotation 590. See FIG. 5A.

[0156] 5B, the present technology provides a phantom system 500 for measuring radiation dose provided by a beam 551 produced by a stationary source 550. In some embodiments, the method includes rotating a patient rotation system about an axis of rotation 590 such that a phantom 501, an electrometer 502, and a cable 505 (e.g., a triaxial cable) of the system 500 rotate about the axis of rotation 590; and producing the beam 551 from the stationary source 550. Thus, in some embodiments, the method includes contacting a detector of the phantom 501 with the beam 551 while the phantom 501 is rotating.

[0157] Thus, phantom system 500 comprises a rotational subsystem comprising phantom 501, electrometer 502, and cable 505 (e.g., triaxial cable); and phantom system 500 also comprises a non-rotating subsystem comprising microprocessor 504. In some embodiments, the rotational subsystem comprises an ADC. In some embodiments, the rotational subsystem comprises a microprocessor or computer with an electrometer. Thus, in some embodiments, data is carried from inside the rotational subsystem (e.g., the phantom side of the system) to outside the rotational subsystem (the user side) across slip ring 503. Furthermore, the charge and / or current output from the detector is sufficiently small to be transmitted from the detector to the electrometer via a special cable (e.g., triaxial cable). Only the signal after the electrometer (e.g., analog charge or current measurement, or a digitized version thereof) is passed through the slip ring to the user side (e.g., outside the radiation bunker).

[0158] Although the disclosure herein refers to certain illustrated embodiments, it should be understood that these embodiments are presented by way of example and not by way of limitation.

[0159] All publications and patents mentioned in the above specification are incorporated herein by reference in their entirety for all purposes. Various modifications and variations of the composition, method, and use of the described technology will be apparent to those skilled in the art without departing from the scope and spirit of the described technology. Although the technology has been described in connection with specific exemplary embodiments, it should be understood that the claimed invention should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention that are obvious to those skilled in the art are intended to be within the scope of the following claims.

Claims

1. 1. A method for measuring a radiation dose provided by a medical radiation system including a patient rotation system and a radiation source, the patient rotation system being configured to rotate about an axis of rotation, the method comprising: placing the phantom on a patient support assembly of a patient rotation system; moving the phantom relative to a radiation beam produced by a radiation source; detecting the radiation beam using a detector; Calculating the radiation dose of the radiation beam; A method comprising:

2. The method of claim 1 , wherein the phantom is placed on the patient support assembly so that the axis of rotation passes through the phantom.

3. 3. The method of claim 1, wherein the phantom is placed on the patient support assembly such that a side wall or an outer surface of the phantom faces the radiation source and the radiation beam passes through the side wall or outer surface.

4. The method of claim 3 , wherein the sidewall or exterior surface is perpendicular to the central axis of the radiation beam.

5. 5. The method of claim 3 or 4, wherein the sidewall or the outer surface is transparent to the radiation beam.

6. The method of claim 1 , wherein moving the phantom comprises rotating the phantom by rotating a patient rotation system about an axis of rotation.

7. The method of claim 1 , wherein moving the phantom comprises translating the phantom by translating a patient support assembly relative to a patient rotation system.

8. The method of claim 1 , wherein the detector is movable within the phantom.

9. 9. The method of claim 8, wherein detecting the radiation beam comprises moving the phantom and moving the detector within the phantom to position the detector to intercept the radiation beam.

10. 10. The method of claim 8 or 9, wherein detecting the radiation beam comprises detecting the radiation beam at a plurality of locations within the phantom.

11. The method of claim 1 , wherein calculating the radiation dose of the radiation beam comprises generating a three-dimensional intensity profile of the radiation beam within the phantom.

12. 12. The method of claim 1, wherein the detector is aligned with the axis of rotation.

13. the calculated radiation dose is a first radiation dose obtained for a first orientation of the phantom, and the method comprises: rotating the phantom to a second orientation different from the first orientation by rotating the patient rotation system about the axis of rotation; detecting the radiation beam in a second orientation using a detector; calculating a second radiation dose of the radiation beam for a second orientation; comparing the second radiation dose to the first radiation dose to obtain a tissue phantom dose ratio; The method of claim 12 further comprising:

14. The method of claim 13 , wherein a length of a first propagation path of the radiation beam within the phantom for the first orientation is different from a length of a second propagation path of the radiation beam within the phantom for the second orientation.

15. Tissue-phantom dose ratio is TPR ２０，１０ 15. The method of claim 14, wherein the length of the first propagation path is 10 cm and the length of the second propagation path is 20 cm, as measured.

16. 16. The method of any one of claims 13 to 15, wherein in the first orientation, a first side wall or outer surface of the phantom facing the radiation source is perpendicular to a central axis of the radiation beam.

17. 17. The method of claim 16, wherein in the second orientation, a second side wall or exterior surface of the phantom facing the radiation source is perpendicular to the central axis of the radiation beam.

18. 18. The method of any one of claims 1 to 17, wherein the radiation source is one of an imaging radiation source or a therapeutic radiation source.

19. 19. The method of any one of claims 1 to 18, wherein the axis of rotation is perpendicular to the radiation beam.

20. 20. The method of any one of claims 1 to 19, wherein the axis of rotation is a vertical axis.

21. 21. The method of any one of claims 1 to 20, wherein the phantom is rigidly attached to a patient support assembly.

22. 22. The method of any one of claims 1 to 21, wherein the patient support assembly comprises an interface for mounting the phantom in a fixed position on the patient support assembly.

23. 23. The method of any one of claims 1 to 22, wherein the phantom is mounted to a seat member of a patient support assembly.

24. 23. The method of any one of claims 1 to 22, wherein the phantom is mounted to an armrest of a patient support assembly.

25. 25. The method of any one of claims 1 to 24, wherein the phantom is placed on a horizontal surface of a patient support assembly.

26. 26. The method of any one of claims 1 to 25, wherein the phantom is disposed horizontally on a patient support assembly such that a central axis of the radiation beam is parallel to a base of the phantom.

27. 26. The method of any one of claims 1 to 25, wherein the phantom is a water phantom comprising a tank, water, and a detector.

28. 26. The method of any one of claims 1 to 25, wherein the phantom is a solid phantom comprising a solid water-equivalent material and a detector.

29. a tank having a base, a first wall, and a second wall; a detector positioned within the tank a first distance from a first wall and a second distance from a second wall; Water and Equipped with a water phantom.

30. 30. The water phantom of claim 29, wherein the first wall and / or the second wall comprise poly(methyl methacrylate).

31. 30. The water phantom of claim 29, wherein the first wall is at a 90° angle from the second wall.

32. 30. The water phantom of claim 29, wherein the detector has a cylindrical shape.

33. 30. The water phantom of claim 29, wherein the detector has a first detection surface parallel to the first wall and a second detection surface parallel to the second wall.

34. 30. The water phantom of claim 29, wherein the first distance is 10 cm and the second distance is 20 cm.

35. 30. The water phantom of claim 29, further comprising a component structured to attach the water phantom to a patient support assembly.

36. 30. The water phantom of claim 29, wherein the detector is located at the axis of rotation of the water phantom.

37. 30. The water phantom of claim 29, further comprising a movable arm operably engaged with the detector.

38. a solid water-equivalent material having a first exterior surface and a second exterior surface; a detector positioned within the solid water-equivalent material a first distance from the first exterior surface and a second distance from the second exterior surface; A solid phantom comprising:

39. 39. The solid phantom of claim 38, wherein the first exterior surface is at a 90° angle from the second exterior surface.

40. 39. The solid phantom of claim 38, wherein the detector has a cylindrical shape.

41. 39. The solid phantom of claim 38, wherein the detector has a first detection face parallel to the first exterior surface and a second detection face parallel to the second exterior surface.

42. 39. The solid phantom of claim 38, wherein the first distance is 10 cm and the second distance is 20 cm.

43. 39. The solid phantom of claim 38, further comprising a component structured to mount the solid phantom to a patient support assembly.

44. 39. The solid phantom of claim 38, wherein the detector is located at the axis of rotation of the solid phantom.

45. 39. The solid phantom of claim 38, wherein the solid water-equivalent material comprises a hole, and a detector is placed in the hole.

46. a medical radiation system; A water phantom, a tank having a base, a first wall, and a second wall; a detector positioned within the tank a first distance from a first wall and a second distance from a second wall; Water and A water phantom A system comprising:

47. a medical radiation system; A solid phantom, a solid water-equivalent material having a first exterior surface and a second exterior surface; a detector positioned within the solid water-equivalent material a first distance from the first exterior surface and a second distance from the second exterior surface; a solid phantom comprising: A system comprising:

48. 48. The system of claim 46 or 47, wherein the medical radiation system comprises an X-ray source.

49. 48. The system of claim 46 or 47, further comprising a patient support assembly.

50. 50. The system of claim 49, wherein the patient support assembly comprises an interface structured to receive the water phantom or the solid phantom.

51. 50. The system of claim 49, wherein the patient support assembly is structured to operatively engage the water phantom or the solid phantom.

52. 50. The system of claim 49, wherein the patient support assembly is structured to move the water phantom or the solid phantom.

53. 50. The system of claim 49, wherein the patient support assembly is structured to rotate the water phantom or the solid phantom.

54. 48. The system of claim 46 or 47, further comprising a beam.

55. 48. The system of claim 46 or 47, further comprising a software component including instructions for rotating the water phantom or the solid phantom.

56. 48. The system of claim 46 or 47, further comprising a software component containing instructions for activating the source to create the beam.

57. 48. The system of claim 46 or 47, further comprising a software component including instructions for receiving data from the detector and using the data to calculate tissue-phantom dose ratios.

58. The tissue-phantom dose ratio is TPR ２０，１０ 58. The system of claim 57, wherein:

59. 47. The system of claim 46, wherein the first wall and / or the second wall comprises poly(methyl methacrylate).

60. 48. The system of claim 46 or 47, wherein the first wall or first exterior surface is at a 90° angle from the second wall or second exterior surface.

61. 48. The system of claim 46 or 47, wherein the detector has a cylindrical shape.

62. 48. The system of claim 46 or 47, wherein the detector has a first detection surface parallel to the first wall or first exterior surface and a second detection surface parallel to the second wall or second exterior surface.

63. 48. The system of claim 46 or 47, wherein the first distance is 10 cm and the second distance is 20 cm.

64. a phantom comprising a detector; Slip ring and a microprocessor; an electrometer that communicates electronically or electrically with the detector through a cable and electronically or electrically with the microprocessor through a slip ring; A phantom system for measuring radiation dose, comprising:

65. 65. The phantom system of claim 64, wherein the phantom is a water phantom.

66. 65. The phantom system of claim 64, wherein the phantom is a solid phantom.

67. 65. The phantom system of claim 64, wherein the cable is a triaxial cable.

68. 65. The phantom system of claim 64, wherein the computer comprises an electrometer.

69. 65. The phantom system of claim 64, further comprising an analog-to-digital converter in electrical communication with the electrometer.

70. 65. The phantom system of claim 64, comprising a rotation subsystem comprising the phantom and an electrometer.

71. 65. A phantom system as in claim 64, comprising a non-rotating subsystem comprising a microprocessor.

72. 1. A method for measuring a radiation dose provided by a medical radiation system including a patient rotation system and a radiation source, the patient rotation system being configured to rotate about an axis of rotation, the method comprising: placing a phantom of the phantom system on a patient support assembly of a patient rotation system; moving the phantom relative to a radiation beam produced by a radiation source; detecting the radiation beam using a detector; producing, by an electrometer, an electrical signal that characterizes the radiation beam; communicating an electrical signal from the electrometer through the slip ring to the microprocessor; calculating a radiation dose of the radiation beam using the signal; A method comprising:

73. 73. The method of claim 72, wherein the phantom is placed on the patient support assembly so that the axis of rotation passes through the phantom.

74. 73. The method of claim 72, wherein moving the phantom comprises rotating the phantom by rotating a patient rotation system about an axis of rotation.

75. 73. The method of claim 72, wherein detecting the radiation beam comprises detecting the radiation beam at a plurality of locations within the phantom.

76. 73. The method of claim 72, wherein calculating the radiation dose of the radiation beam comprises generating a three-dimensional intensity profile of the radiation beam within the phantom.

77. 73. The method of claim 72, wherein the detector is aligned with the axis of rotation.

78. the calculated radiation dose is a first radiation dose obtained for a first orientation of the phantom, and the method comprises: rotating the phantom to a second orientation different from the first orientation by rotating the patient rotation system about the axis of rotation; detecting the radiation beam in a second orientation using a detector; producing, with the electrometer, a second electrical signal characterizing the radiation beam in a second orientation; communicating a second electrical signal from the electrometer through the slip ring to the microprocessor; calculating a second radiation dose of the radiation beam for a second orientation; comparing the second radiation dose to the first radiation dose to obtain a tissue phantom dose ratio; 73. The method of claim 72, further comprising:

79. 79. The method of claim 78, wherein a length of a first propagation path of the radiation beam within the phantom for the first orientation is different from a length of a second propagation path of the radiation beam within the phantom for the second orientation.

80. Tissue-phantom dose ratio is TPR ２０，１０ 79. The method of claim 78, wherein the length of the first propagation path is 10 cm and the length of the second propagation path is 20 cm, as measured.

81. 73. The method of claim 72, wherein in the first orientation, a first side wall or exterior surface of the phantom facing the radiation source is perpendicular to a central axis of the radiation beam.

82. 73. The method of claim 72, wherein in the second orientation, a second side wall or exterior surface of the phantom facing the radiation source is perpendicular to the central axis of the radiation beam.

83. 73. The method of claim 72, wherein the radiation source is one of an imaging radiation source or a therapeutic radiation source.

84. 73. The method of claim 72, wherein the axis of rotation is perpendicular to the radiation beam.

85. 73. The method of claim 72, wherein the axis of rotation is a vertical axis.

86. 73. The method of claim 72, wherein the phantom is rigidly attached to a patient support assembly.

87. 73. The method of claim 72, wherein the patient support assembly comprises an interface for mounting the phantom in a fixed position on the patient support assembly.

88. 73. The method of claim 72, wherein the phantom is mounted to a seat member of a patient support assembly.

89. 73. The method of claim 72, wherein the phantom is mounted to an armrest of a patient support assembly.

90. 73. The method of claim 72, wherein the phantom is placed on a horizontal surface of the patient support assembly.

91. 73. The method of claim 72, wherein the phantom is disposed horizontally on the patient support assembly so that the central axis of the radiation beam is parallel to the base of the phantom.

92. 73. The method of claim 72, wherein the phantom is a water phantom comprising a tank, water, and a detector.

93. 73. The method of claim 72, wherein the phantom is a solid phantom comprising a solid water-equivalent material and a detector.

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