# US 10,502,845 B2 · Techniques for producing an image of radioactive emissions using a compton camera > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,502,845 B2 - Document ID: US10502845B2 - Status: Granted - Kind: B2 - Application number: 15/738,597 - Filed: 2016-06-24 - Published: 2018-07-05 - Granted: 2019-12-10 - Earliest claimed: 2015-06-25 - Assignees: University of Baltimore, Maryland; Board of Regents, The University of Texas System - Applicants: University Of Maryland, Baltimore - Inventors: Jerimy Polf; Emily Draeger; Stephen Peterson; Dennis Mackin; A. Sam Beddar - Web page: https://patentgrep.com/patent/US10502845B2 ## CPC - G01T 1/29: Measurement performed on radiation beams, e.g. position or section of the beam; Measurement of spatial distribution of radiation - A61N 5/1048: {Monitoring, verifying, controlling systems and methods} - A61N 5/1049: {for verifying the position of the patient with respect to the radiation beam} - G01T 1/249: {specially adapted for use in SPECT or PET (SPECT imaging G01T1/1642; PET imaging G01T1/2985; detecting prohibited goods, e.g. weapons, explosives, hazardous substances, contraband or smuggled objects G01V5/20)} - A61N 2005/1052: {using positron emission tomography [PET] single photon emission computer tomography [SPECT] imaging} - A61N 2005/1054: {using a portal imaging system} - A61N 2005/1087: {Ions; Protons} - G01T 1/1642: {using a scintillation crystal and position sensing photodetector arrays, e.g. ANGER cameras} - G01T 1/20: with scintillation detectors - G01T 1/24: with semiconductor detectors - G06T 11/26: Drawing of charts or graphs - G06T 2210/41: Medical - G01T: MEASUREMENT OF NUCLEAR OR X-RADIATION (radiation analysis of materials, mass spectrometry G01N23/00; tubes for determining the presence, intensity, density or energy of radiation or particles H01J47/00) - 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) - G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL ## Abstract Techniques for imaging radioactive emission in a target volume include collecting from each of multiple detectors in a Compton camera, within a coincidence time interval, location and deposited energy from an interaction associated with each high energy particle source event in a target volume, for N source events. A cone of possible locations for each source event is determined based on the locations and deposited energies collected. A SOE algorithm is initiated by selecting a random location on the cone and generating a histogram that indicates, a count of the selected locations that occur inside each voxel of the target volume. N solution locations for the N source events are determined after L iterations by updating the selected location on a corresponding cone based at least in part on values of the counts in the histogram excluding the current source event. A solution is presented on a display device. ## Claims ### Claim 1 A method implemented on a processor comprising: receiving first data indicating locations of a plurality of voxels of target resolution v in a target volume of a subject; collecting from each of a plurality of detectors in one or more stages of a Compton camera within a coincidence time interval, location and deposited energy from an interaction associated with each high energy particle source event in the target volume, for a plurality of N source events in the target volume; determining for each source event a cone of possible locations for the source event based on the locations and deposited energies collected from the plurality of detectors in one or more stages of the Compton camera; initiating a stochastic origins ensemble (SOE) iterative algorithm by selecting for each source event a random location on the cone of possible locations for a corresponding source event and generating a histogram that indicates, for each voxel, a count of the selected locations that occur inside the voxel; determining a solution comprising a set of N solution locations for the N source events from the SOE iterative algorithm after L iterations by updating for each source event during each iteration the selected location on the corresponding cone based at least in part on values of the counts in the histogram excluding the current source event, and updating the histogram based on the updated selected location for each source event during each iteration; and, presenting, on a display device, data indicating at least one solution location of the set of N solution locations. ### Claim 2 (depends on 1) The method of claim 1, wherein each of the plurality of N source events is used once without replacement as the current source event, during each iteration of the L iterations. ### Claim 3 (depends on 1) The method of claim 1, wherein the source event is a gamma ray emission and the cause of the source event is a proton beam interacting with an atom in the subject. ### Claim 4 (depends on 1) The method of claim 1, wherein the source event is a gamma ray emission and the cause of the source event is a positron-emitting radionuclide as used in positron emission tomography (PET) medical imaging. ### Claim 5 (depends on 4) The method of claim 4, wherein collecting from each of the plurality of detectors in one or more stages of the Compton camera within the coincidence time interval, location and deposited energy from an interaction associated with the source event in the target volume further comprises selecting from each of only two detectors in one or more stages of the Compton camera within the coincidence time interval, location and deposited energy wherein a sum of the deposited energies in the two detectors is about equal to an energy of a gamma ray emitted by annihilation of the positron produced by the positron-emitting radionuclide. ### Claim 6 (depends on 1) The method of claim 1, wherein the source event is a gamma ray emission and the cause of the source event is a gamma-emitting radioisotope as used in single-photon emission computed tomography (SPECT) medical imaging. ### Claim 7 (depends on 6) The method of claim 6, wherein collecting from each of the plurality of detectors in one or more stages of the Compton camera within the coincidence time interval, location and deposited energy from an interaction associated with the source event in the target volume further comprises selecting from each of only two detectors in one or more stages of the Compton camera within the coincidence time interval, location and deposited energy wherein a sum of the deposited energies in the two detectors is about equal to an energy of a gamma ray emitted by the gamma-emitting radioisotope. ### Claim 8 (depends on 1) A computer-readable medium carrying one or more sequences of instructions, wherein execution of the one or more sequences of instructions by one or more processors causes the one or more processors to perform the steps of the method of claim 1. ### Claim 9 (depends on 1) A system comprising: a Compton camera comprising a plurality of detectors in one or more stages, each stage comprising an array of detectors for a high energy particle; at least one processor; and at least one memory including one or more sequences of instructions, the at least one memory and the one or more sequences of instructions configured to, with the at least one processor, cause the system to perform at least the steps of the method of claim 1. ### Claim 10 A method implemented on a processor comprising: a) receiving first data indicating locations of a plurality of voxels of target resolution v in a volume of a subject; b) collecting from each of a plurality of detectors in one or more stages of a Compton camera within a coincidence time interval, location and deposited energy from an interaction associated with each high energy particle source event in the subject volume, for a plurality of N source events in the subject volume; c) determining for each source event a cone of possible locations for the source event based on the locations and deposited energies collected from the plurality of detectors in one or more stages of the Compton camera, d) initiating an instance of an stochastic origins ensemble (SOE) iterative algorithm by selecting for each source event a random location on the cone of possible locations for a corresponding source event; e) determining an instance of a solution comprising a set of N solution locations for the N source events from the SOE iterative algorithm after L iterations; f) repeating steps d and e for a plurality of M instances of the SOE iterative algorithm selecting for each source event M different random locations on the cone to initiate the plurality of M instances and to determine a plurality of M instances of a solution; g) combining the plurality of M instances of the solution location for each source event to determine a combined solution location for each of the N source events; and h) presenting, on a display device, data indicating the combined solution location for at least one source event of the N source events. ### Claim 11 (depends on 10) A computer-readable medium carrying one or more sequences of instructions, wherein execution of the one or more sequences of instructions by one or more processors causes the one or more processors to perform the steps of the method of claim 10. ### Claim 12 (depends on 10) A system comprising: a Compton camera comprising a plurality of detectors in one or more stages, each stage comprising an array of detectors for a high energy particle; at least one processor; and at least one memory including one or more sequences of instructions, the at least one memory and the one or more sequences of instructions configured to, with the at least one processor, cause the system to perform at least the steps of the method of claim 10.