# US 2025/0144447 A1 · Methods, apparatus and computer-readable media for managing radiotherapy > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0144447 A1 - Document ID: US20250144447A1 - Status: Published application - Kind: A1 - Application number: 18/615,652 - Filed: 2024-03-25 - Published: 2025-05-08 - Earliest claimed: 2023-05-11 - Assignees: Elekta Limited - Applicants: Elekta Limited - Inventors: Kathrin HOLMES; Gary CLARK - Web page: https://patentgrep.com/patent/US20250144447A1 ## CPC - A61N 5/103: {Treatment planning systems} - A61N 5/1031: {using a specific method of dose optimization} - A61N 5/1081: {Rotating beam systems with a specific mechanical construction, e.g. gantries} - A61N: ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY (measurement of bioelectric currents A61B; surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body A61B18/00; anaesthetic apparatus in general A61M; incandescent lamps H01K; infrared radiators for heating H05B) ## Abstract A method is disclosed, performed by a management apparatus for a radiotherapy system, the radiotherapy system comprising a source of therapeutic radiation mounted on a rotatable gantry. The method comprises: receiving, from a treatment planning apparatus, a treatment plan for delivery by the radiotherapy system, the treatment plan specifying a plurality of beams to be generated by the source of therapeutic radiation, wherein each beam is associated with first and second angles of the rotatable gantry, wherein the beam is initiated at one of the first and second angles, and terminated at the other of the first and second angles; applying an optimization algorithm to the plurality of beams, the optimization algorithm arranging the plurality of beams into an order such that an aggregate amount of rotation by the rotatable gantry between beams when delivering the treatment plan is minimized; and outputting the ordered plurality of beams to the radiotherapy system for implementation. ## Claims ### Claim 1 A method performed by a management apparatus for a radiotherapy system, the radiotherapy system comprising a source of therapeutic radiation mounted on a rotatable gantry, the method comprising: receiving, from a treatment planning apparatus, a treatment plan for delivery by the radiotherapy system, the treatment plan specifying a plurality of beams to be generated by the source of therapeutic radiation, wherein each beam is associated with first and second angles of the rotatable gantry, wherein the beam is initiated at one of the first and second angles, and terminated at the other of the first and second angles; applying an optimization algorithm to the plurality of beams, the optimization algorithm arranging the plurality of beams into an order such that an aggregate amount of rotation by the rotatable gantry between beams when delivering the treatment plan is minimized; and outputting the ordered plurality of beams to the radiotherapy system for implementation. ### Claim 2 (depends on 1) The method according to claim 1, wherein the optimization algorithm further specifies a direction of rotation between the first and second angles for each beam. ### Claim 3 (depends on 1) The method according to claim 1, wherein the plurality of beams is arranged into an order in which an aggregate amount of rotation by the rotatable gantry between beams when delivering the treatment plan is reduced, taking into account a final angle of rotation of the rotatable gantry from an immediately preceding treatment plan delivered by the radiotherapy apparatus. ### Claim 4 (depends on 1) The method according to claim 1, wherein the optimization algorithm comprises: a. placing an initial beam from the plurality of beams into an intermediate order; b. placing a subsequent beam from a remainder of the plurality of beams into the intermediate order, wherein the subsequent beam is placed at a position in the intermediate order such that the aggregate amount of rotation by the rotatable gantry between beams in the intermediate order is minimized; and c. repeating step b until the plurality of beams are arranged into the order. ### Claim 5 (depends on 4) The method according to claim 4, wherein step b comprises calculating aggregate amounts of rotation by the rotatable gantry with the subsequent beam at each possible position in the intermediate order, and placing the subsequent beam at a position in the intermediate order having the smallest aggregate amount of rotation of the rotatable gantry between beams according to the intermediate order. ### Claim 6 (depends on 4) The method according to claim 4, wherein step b comprises calculating aggregate amounts of rotation by the rotatable gantry with the subsequent beam placed at each possible position in the intermediate order and in each direction between the first and second angles, and placing the subsequent beam at a position in the intermediate order and in a direction of rotation having the smallest aggregate amount of rotation of the rotatable gantry between beams according to the intermediate order. ### Claim 7 (depends on 4) The method according to claim 4, wherein the optimization algorithm further specifies a direction of rotation between the first and second angles for each beam, and wherein step b comprises placing a subsequent beam from a remainder of the plurality of beams into the intermediate order such that the aggregate amount of rotation by the rotatable gantry between beams in the intermediate order is minimized, taking into account a final angle of rotation of the rotatable gantry from an immediately preceding treatment session delivered by the radiotherapy apparatus. ### Claim 8 (depends on 4) The method according to claim 4, wherein step b comprises placing a subsequent beam from a remainder of the plurality of beams into the intermediate order such that the aggregate amount of rotation by the rotatable gantry between beams in the intermediate order is minimized, taking into account an imaging position of the rotatable gantry. ### Claim 9 (depends on 1) The method according to claim 1, wherein the optimization algorithm comprises calculating an aggregate amount of rotation by the rotatable gantry between beams for each possible order of the plurality of beams, and selecting the order having the smallest aggregate amount of rotation by the rotatable gantry between beams. ### Claim 10 (depends on 1) The method according to claim 1, wherein the first angle for a first beam of the plurality of beams is different to the second angle for the first beam. ### Claim 11 (depends on 10) The method according to claim 10, wherein the respective first angle for each beam of the plurality of beams is different to the respective second angle. ### Claim 12 (depends on 1) The method according to claim 1, wherein the first angle for a second beam of the plurality of beams is the same as the second angle for the second beam. ### Claim 13 (depends on 1) The method according to claim 1, wherein the method is performed at run-time of the treatment plan by the radiotherapy system. ### Claim 14 (depends on 1) The method according to claim 1, wherein the treatment planning apparatus is co-located with the management apparatus. ### Claim 15 A management apparatus for a radiotherapy system, comprising processing circuitry and a non-transitory computer-readable medium storing instructions which, when executed by the processing circuitry, cause the management apparatus to: receive, from a treatment planning apparatus, a treatment plan for delivery by a radiotherapy system comprising a source of therapeutic radiation mounted on a rotatable gantry, the treatment plan specifying a plurality of beams to be generated by the source of therapeutic radiation, wherein each beam is associated with first and second angles of the rotatable gantry, wherein the beam is initiated at one of the first and second angles, and terminated at the other of the first and second angles; apply an optimization algorithm to the plurality of beams, the optimization algorithm arranging the plurality of beams into an order such that an aggregate amount of rotation by the rotatable gantry between beams when delivering the treatment plan is minimized; and output the ordered plurality of beams to the radiotherapy system for implementation. ### Claim 16 A non-transitory computer-readable medium storing instructions which, when executed by processing circuitry, cause the processing circuitry to: receive, from a treatment planning apparatus, a treatment plan for delivery by a radiotherapy system comprising a source of therapeutic radiation mounted on a rotatable gantry, the treatment plan specifying a plurality of beams to be generated by the source of therapeutic radiation, wherein each beam is associated with first and second angles of the rotatable gantry, wherein the beam is initiated at one of the first and second angles, and terminated at the other of the first and second angles; apply an optimization algorithm to the plurality of beams, the optimization algorithm arranging the plurality of beams into an order such that an aggregate amount of rotation by the rotatable gantry between beams when delivering the treatment plan is minimized; and output the ordered plurality of beams to the radiotherapy system for implementation.