# US 7,609,810 B2 · Treatment-speed regulated tumor-tracking > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,609,810 B2 - Document ID: US7609810B2 - Status: Granted - Kind: B2 - Application number: 11/956,697 - Filed: 2007-12-14 - Published: 2008-06-19 - Granted: 2009-10-27 - Earliest claimed: 2006-12-14 - Inventors: Byong Yong Yi; Xinsheng Cedric Yu; Fritz Lerma - Web page: https://patentgrep.com/patent/US7609810B2 ## CPC - A61N 5/1049: {for verifying the position of the patient with respect to the radiation beam} - A61N 5/1037: {taking into account the movement of the target, e.g. 4D-image based planning} - A61N 5/1042: {with spatial modulation of the radiation beam within the treatment head} - A61N 5/1067: {in real time, i.e. during treatment} - A61N 2005/1087: {Ions; Protons} - 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 for delivering therapeutic radiation to a tumor within a patient including: monitoring tumor motion in a preliminary procedure to generate and record a surrogate signal representing the tumor motion; determining a radiation therapy plan for the patient including a planned sequence of varying parameters of a radiation beam to track the tumor motion and a planned rate of execution of the planned sequence; configuring a radiation therapy device to deliver radiation in accordance with the radiation therapy plan, positioning the patient within the device, and activating the device to perform the planned sequence; monitoring tumor motion during the procedure to provide a treatment surrogate signal; determining the difference between the estimated and treatment surrogate signals; and regulating the speed of the radiation treatment procedure by varying the rate of execution of the sequence of beam parameters in accordance with the difference between the estimated and treatment surrogate signals. ## Claims ### Claim 1 A method for delivering therapeutic radiation during a radiation treatment procedure to a tumor moving within a patient due to physiological activity of said patient, comprising: in a preliminary procedure, monitoring motion of said tumor in location and shape over a time period corresponding to said radiation treatment procedure, generating a surrogate signal representing said motion of said tumor, and recording said signal in a recording device to provide an estimated surrogate signal; determining a radiation therapy plan for the patient, wherein the radiation therapy plan defines a planned sequence of varying parameters of a radiation beam to track the tumor motion and a planned rate of execution of said sequence of parameters; configuring a radiation therapy device to deliver radiation in accordance with the radiation therapy plan; positioning the patient within said radiation therapy device; activating the radiation therapy device to perform said planned sequence of parameters of said radiation beam; monitoring tumor motion during said radiation therapy procedure to provide a treatment surrogate signal; determining the difference between said estimated surrogate signal and said treatment surrogate signal; and regulating the speed of said radiation treatment procedure by varying the rate of execution of said sequence of radiation beam parameters in accordance with said difference between said estimated surrogate signal and said treatment surrogate signal. ### Claim 2 (depends on 1) The method of claim 1 wherein said parameters of the radiation beam include at least one of dose rate, dose accumulation rate, radiation energy, rate of variation of said radiation energy, configuration of a mechanical or electronic range modulator (RM) for a charged particle beam, individual leaf positions of a multi-leaf collimator, positions of a group of leaves of the multi-leaf collimator, position and orientation of the multi-leaf collimator carriage, size and shape of a radiation field defined by an opening of the multi-leaf collimator, gantry angle, gantry speed, collimator angle or position and orientation of a patient-supporting table. ### Claim 3 (depends on 1) The method of claim 1, wherein said rate of execution of said sequence of radiation beam parameters is regulated by regulating a value of a leading control variable of said radiation therapy device. ### Claim 4 (depends on 3) The method of claim 3, wherein said leading variable is a value of delivered monitor units of radiation. ### Claim 5 (depends on 4) The method of claim 4, wherein the dose rate is regulated by regulating a pulse rate at which the radiation therapy device delivers pulses of radiation to the patient. ### Claim 6 (depends on 4) The method of claim 4, wherein the dose rate is regulated by periodically gating said radiation therapy device. ### Claim 7 (depends on 4) The method of claim 4, wherein the dose rate is regulated by regulating a pulse width at which the radiation therapy device delivers pulses of radiation to the patient. ### Claim 8 (depends on 3) The method of claim 3, wherein said leading variable is a dose rate of said radiation. ### Claim 9 (depends on 1) The method of claim 1, wherein said radiation therapy device is a megavoltage electron accelerator, a charged particle accelerator, or a radionuclide radiation device. ### Claim 10 (depends on 1) The method of claim 1, wherein said speed of said radiation treatment procedure is regulated to achieve synchrony between said estimated surrogate signal and said treatment surrogate signal at least within a within a time period that is short with respect to one breathing cycle of said patient. ### Claim 11 (depends on 1) The method of claim 1, wherein an initial portion of said treatment surrogate signal is extrapolated to serve as an estimated surrogate signal for subsequent portions of said radiation therapy treatment procedure. ### Claim 12 A system for regulating the speed of radiation therapy treatment delivered to a patient by a radiation therapy device, comprising: a detection mechanism for obtaining the time course of tumor motion (shape and location change) and its correlation with a measurable surrogate, typically a physical signal associated with breathing or the location of implanted markers in the tumor, for a patient in need of radiation therapy; a determining mechanism for determining a radiation therapy plan for the patient, the radiation therapy plan including a target location that varies in accordance with the estimated breathing pattern; a configuring mechanism for configuring the radiation therapy device to deliver radiation in accordance with the radiation therapy plan; an activating mechanism for activating the radiation therapy device; a monitoring mechanism for monitoring an actual breathing pattern of the patient during delivery of radiation; a second determining mechanism for determining a difference between the estimated breathing pattern and the actual breathing pattern of the patient; and a regulating mechanism for regulating a treatment speed of the radiation therapy device in accordance with the difference. ### Claim 13 (depends on 12) The system of claim 12, wherein the dose rate is regulated by regulating a pulse rate at which the radiation therapy device delivers pulses of radiation to the patient. ### Claim 14 (depends on 12) The system of claim 12, wherein the dose rate is regulated by regulating a pulse width at which the radiation therapy device delivers pulses of radiation to the patient. ### Claim 15 (depends on 12) The system of claim 12, wherein the radiation therapy device is mounted on a moving gantry, said moving gantry moving at a specified gantry speed, and the gantry speed is regulated by a mechanical breaker. ### Claim 16 (depends on 15) The system of claim 15, wherein the radiation therapy device is provided with a multi-leaf collimator, a dose rate of said radiation therapy is regulated by moving leaves of said multi-leaf collimator under control of said configuring mechanism, and said moving gantry may assume angular positions during said radiation therapy deviating from planned angular positions of said gantry by a predetermined amount. ### Claim 17 (depends on 16) The system of claim 16, wherein said gantry may assume angular positions during said radiation treatment deviating from said planned angular oppositions by an amount not exceeding about 5 degrees of arc. ### Claim 18 (depends on 12) The system of claim 12, wherein a rate of change of a dose rate of said radiation therapy is regulated by providing gating signals to said radiation therapy device. ### Claim 19 (depends on 12) The system of claim 12, wherein said radiation therapy device includes a charged particle beam having a mechanical range modulator and said modulator is controlled by regulating a pulse rate thereof. ### Claim 20 (depends on 12) The system of claim 12, wherein said radiation therapy device includes a charged particle beam having a mechanical range modulator and said modulator is controlled by regulating a pulse width thereof. ### Claim 21 (depends on 12) The system of claim 12, wherein said radiation therapy device includes a charged particle beam having a digital range modulator and said modulator is controlled by regulating a pulse rate thereof. ### Claim 22 (depends on 12) The system of claim 12, wherein said radiation therapy device includes a charged particle beam having a mechanical range modulator and said modulator is controlled by regulating a pulse width thereof. ### Claim 23 (depends on 12) The system of claim 12, wherein said determining mechanism for determining a radiation therapy plan for the patient, determines a radiation therapy plan for a target that moves throughout an estimated range of motion of a tissue to be treated.