Canon Medical Systems Corporation

Jeffrey Kolthammer

Yi Qiang

Evren Asma

Wenyuan Qi

Li Yang

Xiaoli Li

Peng Peng

Yujie Lu

Zhou Yu

Kent C Burr

Manabu Teshigawara

Chung Chan

Ryo Okuda

Masaki Miyahara

A positron emission tomography (PET) scanner is provided having a plurality of detector subsystems, including processing circuitry to determine, for each detector subsystem of the plurality of detector subsystems, a singles count loss correction factor of the detector subsystem; determine, for each detector subsystem pair of a plurality of pairs of the detector subsystems, a coincidence count loss correction factor for the detector subsystem pair; calculate a scanner coincidence count loss correction factor for the PET scanner based on the coincidence count loss correction factors determined for the plurality of pairs of the detector subsystems; and reconstruct an image based on the calculated scanner count loss correction factor and scan data acquired from a scan of a patient performed using the PET scanner.

Method for correction of correlated count losses

A PET scanner includes gamma-ray detector rings that form a bore through which an imaging subject is translated, a length of the bore defining an axial length of the PET scanner, the gamma-ray detector rings being movable along the axial length, the gamma-ray detector rings including gamma-ray detector modules therein, and processing circuitry configured to receive PET data associated with a plurality of transaxial slices of the imaging subject, the PET data including a first set of spatial information and timing information corresponding to a first data acquisition period for the gamma-ray detector modules in a first axial position and a second set of spatial information and timing information corresponding to a second data acquisition period for the gamma-ray detector modules in a second axial position, and reconstruct a PET image based on the first set of spatial and timing information and the second set of spatial and timing information.

Pet reconstruction for adjustable pet system

Existing, low quality images can be restored using reconstruction or a combination of post-reconstruction techniques to generate a real patient phantom. The real patient phantom (RPP) can then be simulated in Monte Carlo simulations of a higher performance system and a lower performance system. Alternatively, the RPP can be simulated in the higher performance system, and a real scan can be performed by an existing, lower performance system. The higher performance system can be differentiated from the lower performance system in a variety of ways, including a higher resolution time of flight measurement capability, a greater sensitivity, smaller detector crystals, or less scattering. A neural network can be trained using the images produce by the higher performance system as the target, and the images produced by the lower performance system as the input. After training, the trained neural network can be used to output input images taken in a lower performance system with higher performance system characteristics.

Neural network for improved performance of medical imaging systems

A guided pairing method includes generating a singles list by detecting a plurality of singles at a plurality of detector elements in a detector array, the plurality of singles falling within a plurality of detection windows; for each detection window of the plurality of detection windows in the singles list having exactly two singles of the plurality of singles, determining the line of responses (LORs) for each of the two singles of the plurality of singles; for each detection window of the plurality of detection windows in the singles list having more than two singles of the plurality of singles, determining all coincidences possible based on the more than two singles; generating a weight for said each coincidence of the coincidences based on the determined LORs for said each of the two singles of the plurality of singles; and pairing the more than two singles based on the generated weight for said each coincidence of the coincidences.

Method and apparatus for guided pairing of multi-coincidences for time of flight positron emission tomography

A method of normalizing detector elements in an imaging system is described herein. The method includes a line source that is easier to handle for a user, and decouples the normalization of the detector elements into a transaxial domain and an axial domain in order to isolate errors due to positioning of the line source. Additional simulations are performed to augment the real scanner normalization. A simulation of a simulated line source closely matching the real line source can be performed to isolate errors due to physical properties of the crystals and position of the crystals in the system, wherein the simulated detector crystals are otherwise modeled uniformly. A simulation of a simulated cylinder source can be performed to determine errors due to other effects stemming from gaps between the detector crystals.

Method and system for PET detector efficiency normalization

The present disclosure is related to removing scatter from a SPECT scan by utilizing a radiative transfer equation (RTE) method. An attenuation map and emission map are acquired for generating scatter sources maps and scatter on detectors using the RTE method. The estimated scatter on detectors can be removed to produce an image of a SPECT scan with less scatter. Both first-order and multiple-order scatter can be estimated and removed. Additionally, scatter caused by multiple tracers can be determined and removed.

Total SPECT scatter estimation and correction using radiative transfer equation

The present disclosure relates to an apparatus for estimating scatter in positron emission tomography, comprising processing circuitry configured to acquire an emission map and an attenuation map, each representing an initial image reconstruction of a positron emission tomography scan, calculate, using a radiative transfer equation (RTE) method, a scatter source map of a subject of the positron emission tomography scan based on the emission map and the attenuation map, estimate, using the RTE method and based on the emission map, the attenuation map, and the scatter source map, scatter, and perform an iterative image reconstruction of the positron emission tomography scan based on the estimated scatter and raw data from the positron emission tomography scan of the subject.

Method and apparatus for scatter estimation in positron emission tomography

A positron emission tomography scanner includes a plurality of gamma-ray detector rings that form a bore through which an imaging subject is translated, each of the plurality of gamma-ray detector rings being in a first axial position, and processing circuitry configured to receive attenuation data associated with a plurality of transaxial slices of the imaging subject, determine a second axial position of each of the plurality of gamma-ray detector rings based on the received attenuation data, and adjust a position of each of the plurality of gamma-ray detector rings from the first axial position to the second axial position. The processing circuitry may further be configured to calculate an attenuation metric based on the received attenuation data, and determine the second axial position such that the attenuation metric calculated for each pair of adjacent gamma-ray detector rings is equal.

Growing community of inventors

Vernon Hills, IL, United States of America

Jeffrey Kolthammer