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EP-4740173-A1 - REGION-BASED MOTION CORRECTION USING EXTRA MODAL INFORMATION FOR SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY

EP4740173A1EP 4740173 A1EP4740173 A1EP 4740173A1EP-4740173-A1

Abstract

For correction of motion in single photon emission computed tomography (SPECT) imaging, extra modal information is used to delineate different regions in a patient. Motion in these different regions as reflected in SPECT data is determined. These regional motions are used for motion correction. Statistical measurements for the SPECT data of the different regions may be used to weight the regional motions.

Inventors

  • VIJA, ALEXANDER HANS
  • REYMANN, Maximilian

Assignees

  • Siemens Medical Solutions USA, Inc.

Dates

Publication Date
20260513
Application Date
20230810

Claims (20)

  1. 1 . A method for correction of motion in a single photon emission computed tomography (SPECT) imaging system, the method comprising: detecting, with a SPECT detector, emissions over time from a patient, the detected emissions comprising first projection data and are subject to the motion of the patient; estimating region motions for different regions of the patient from the first projection data, the different regions designated by extra modal information; motion correcting the first projection data or data derived from the first projection data based on the estimated region motions; and displaying a SPECT image from the motion corrected first projection data or the data derived from the first projection data.
  2. 2. The method of claim 1 further comprising segmenting the extra modal information, the segmenting providing masks for the different regions, the different regions comprising different anatomy or functional area of the patient.
  3. 3. The method of claim 2 further comprising projecting the extra modal information as segmented, the projection generating the masks.
  4. 4. The method of claim 1 wherein the extra modal information comprises computed tomography, magnetic resonance, ultrasound, positron emission tomography, or x-ray imaging of the patient.
  5. 5. The method of claim 1 wherein the motion of the patient comprises respiratory motion of the patient, and wherein motion correcting comprises motion correcting for the respiratory motion.
  6. 6. The method of claim 1 wherein estimating comprises estimating amplitude of the first projection data as a function of time for each of the different regions as the region motions.
  7. 7. The method of claim 1 further comprising determining a statistical measurement for each of the different regions, wherein motion correcting comprises motion correcting based on the estimated region motions and the statistical measurements.
  8. 8. The method of claim 7 wherein the statistical measurement comprises count rate density of the respective region, count rate density ratios between the different regions, maximum range of motions within the different regions, adjacent view motion from an adjacent view of the SPECT detector, noise, or signal-to-noise ratio, and wherein motion correcting comprises motion correcting based on the estimated region motions weighted by the statistical measurement for each of the different regions.
  9. 9. The method of claim 1 wherein motion correcting comprises motion correcting based on a weighted combination of the region motions, weighting in the weighted combination being based on a statistical measurement.
  10. 10. The method of claim 9 wherein the weighting comprises selecting one of the region motions based on the statistical measurement.
  11. 11 . The method of claim 1 wherein motion correcting comprises motion correcting the first projection data as list mode data or a frame prior to reconstructing the SPECT image.
  12. 12. The method of claim 1 wherein motion correcting comprises motion correcting reconstruction data in a reconstruction, the reconstruction data comprising the data derived from the first projection data.
  13. 13. A method for correction of motion in a single photon emission computed tomography (SPECT) imaging system, the method comprising: determining a motion correction to counteract the motion, the determination being based on region delineation from information of a different modality than the SPECT; and generating a SPECT image as motion corrected using the motion correction.
  14. 14. The method of claim 13 wherein the region delineation comprises segmentation of different organs, the motion correction determined from a set of region motions for the different organs.
  15. 15. The method of claim 13 wherein the different modality comprises computed tomography, magnetic resonance, ultrasound, positron emission tomography, or x-ray, the region delineation being segmentations forward projected to a projection data space of SPECT data, the motion correction being from different motions determined from the SPECT data using the segmentations as forward projected.
  16. 16. The method of claim 13 wherein determining the motion correction comprises a weighted combination of regional motions from the region delineation.
  17. 17. The method of claim 16 wherein the weighted combination comprises weighting the regional motions using a statistical measure of SPECT data of respective regions from the region delineation.
  18. 18. A single photon computed tomography (SPECT) system comprising: a SPECT detector for detecting signals from a patient; a motion processor configured to determine motions for different regions of the patient from the detected signals, the different regions segmented from imaging of a modality other than the SPECT ; a reconstruction processor configured to reconstruct a SPECT image of the signals from the patient, the SPECT image being motion corrected based on the motions for the different regions; and a display configured to display the SPECT image.
  19. 19. The SPECT system of claim 18 wherein the reconstruction processor is configured to apply motion correction to the signals as frames or list mode data prior to the reconstruction of the SPECT image, the motion correction comprising a weighted combination of the motions of the different regions.
  20. 20. The SPECT system of claim 19 wherein the weighted combination has weights based on statistical measures of the detected signals.

Description

REGION-BASED MOTION CORRECTION USING EXTRA MODAL INFORMATION FOR SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY BACKGROUND [0001] The present embodiments relate to motion correction in single photon emission computed tomography (SPECT) imaging. Patient motion (e.g., respiratory, voluntary, involuntary, or activity shifts) may cause blur and/or artifacts in SPECT imaging. [0002] Analysis of the consistency of the SPECT data itself can enable the correction of motion in SPECT projection data. A one-dimensional (1 D) respiratory motion signal may be used to correct for the motion of the entire projection data. However, respiratory motion is a 3D heterogeneous motion. [0003] View-by-view inconsistencies in SPECT data due to motion may be corrected using extra-modal data. Respiratory motion may be corrected using SPECT data driven methods. These corrections do not manage multiple motions in a dataset and assume all objects within the frame move with the same trajectory. If there are multiple moving objects or features in a dataset that result in a constant center of light, these methods do not correct any motion. SUMMARY [0004] By way of introduction, the preferred embodiments described below include methods, systems, and non-transitory computer readable media for correction of motion in SPECT imaging. Extra modal information is used to delineate different regions in a patient. Motion in these different regions as reflected in SPECT data is determined. These regional motions are used for motion correction. Statistical measurements for the SPECT data of the different regions may be used to weight the regional motions. [0005] In a first aspect, a method is provided for correction of motion in a single photon emission computed tomography (SPECT) imaging system. A SPECT detector detects emissions over time from a patient. The detected emissions include first projection data and are subject to the motion of the patient. Regional motions are estimated for different regions of the patient from the first projection data. The different regions are designated by extra modal information. The first projection data or data derived from the first projection data is motion corrected based on the estimated region motions. A SPECT image from the motion corrected first projection data or the data derived from the first projection data is displayed. [0006] As a further approach, the extra modal information is segmented, providing masks for the different regions. The different regions are for different anatomy or functional area of the patient. In a further approach, the extra modal information as segmented is projected, the projection generating the masks. [0007] In one embodiment, the extra modal information is computed tomography, magnetic resonance, ultrasound, positron emission tomography, or x-ray imaging of the patient. [0008] In another embodiment, the motion of the patient is respiratory motion of the patient. The motion correction is for the respiratory motion. [0009] According to another embodiment, the regional motions are estimated as amplitude of the first projection data as a function of time for each of the different regions. [0010] In yet another embodiment, a statistical measurement is determined for each of the different regions. The motion correction is based on the estimated region motions and the statistical measurements. For example, the statistical measurement is count rate density of the respective region, count rate density ratios between the different regions, maximum range of motions within the different regions, adjacent view motion from an adjacent view of the SPECT detector, noise, or signal-to-noise ratio. Other statistical measurements may be used. The motion correction is based on the estimated region motions weighted by the statistical measurement for each of the different regions. [0011] As one embodiment, the motion correction is based on a weighted combination of the regional motions. The weighting in the weighted combination is based on a statistical measurement. For example, the weighting selects one of the region motions based on the statistical measurement. [0012] In one embodiment, the motion correction corrects the first projection data as list mode data or a frame prior to reconstructing the SPECT image. In another embodiment, the motion correction corrects reconstruction data in a reconstruction. The reconstruction data is the data derived from the first projection data. [0013] In a second aspect, a method is provided for correction of motion in a single photon emission computed tomography (SPECT) imaging system. A motion correction to counteract the motion is determined. The determination is based on region delineation from information of a different modality than the SPECT. A SPECT image as motion corrected using the motion correction is generated. [0014] In one implementation, the region delineation includes segmentation of different organs. The motion correction is determined from a