Phase calibration of a physiological motion detector

1971 ◽  
Vol 9 (4) ◽  
pp. 401-402
Author(s):  
R. N. Stiles ◽  
R. S. Pozos ◽  
A. C. York
Keyword(s):  
Motion Detector ◽  
Phase Calibration ◽  
Physiological Motion

A Simple Transverse Motion Detector for Railguns

2004 ◽  
Author(s):  
S. J. Levinson ◽  
Stephan Bless
Keyword(s):  
Transverse Motion ◽  
Motion Detector

scholarly journals Imaging coronary plaques using 3D motion-compensated [18F]NaF PET/MR

2021 ◽  
Author(s):  
Johannes Mayer ◽  
Thomas-Heinrich Wurster ◽  
Tobias Schaeffter ◽  
Ulf Landmesser ◽  
Andreas Morguet ◽  
...  
Keyword(s):  
Attenuation Correction ◽  
Free Breathing ◽  
Cardiac Motion ◽  
Water Fraction ◽  
3 Dimensional ◽  
Background Ratio ◽  
Motion Models ◽  
Physiological Motion ◽  
Atherosclerosis Imaging ◽  
Novel Applications

Abstract Background Cardiac PET has recently found novel applications in coronary atherosclerosis imaging using [18F]NaF as a radiotracer, highlighting vulnerable plaques. However, the resulting uptakes are relatively small, and cardiac motion and respiration-induced movement of the heart can impair the reconstructed images due to motion blurring and attenuation correction mismatches. This study aimed to apply an MR-based motion compensation framework to [18F]NaF data yielding high-resolution motion-compensated PET and MR images. Methods Free-breathing 3-dimensional Dixon MR data were acquired, retrospectively binned into multiple respiratory and cardiac motion states, and split into fat and water fraction using a model-based reconstruction framework. From the dynamic MR reconstructions, both a non-rigid cardiorespiratory motion model and a motion-resolved attenuation map were generated and applied to the PET data to improve image quality. The approach was tested in 10 patients and focal tracer hotspots were evaluated concerning their target-to-background ratio, contrast-to-background ratio, and their diameter. Results MR-based motion models were successfully applied to compensate for physiological motion in both PET and MR. Target-to-background ratios of identified plaques improved by 7 ± 7%, contrast-to-background ratios by 26 ± 38%, and the plaque diameter decreased by −22 ± 18%. MR-based dynamic attenuation correction strongly reduced attenuation correction artefacts and was not affected by stent-related signal voids in the underlying MR reconstructions. Conclusions The MR-based motion correction framework presented here can improve the target-to-background, contrast-to-background, and width of focal tracer hotspots in the coronary system. The dynamic attenuation correction could effectively mitigate the risk of attenuation correction artefacts in the coronaries at the lung-soft tissue boundary. In combination, this could enable a more reproducible and reliable plaque localisation.

scholarly journals A Model for an Angular Velocity-Tuned Motion Detector Accounting for Deviations in the Corridor-Centering Response of the Bee

2016 ◽  
Vol 12 (5) ◽  
pp. e1004887 ◽  
Author(s):  
Alex J. Cope ◽  
Chelsea Sabo ◽  
Kevin Gurney ◽  
Eleni Vasilaki ◽  
James A. R. Marshall
Keyword(s):  
Angular Velocity ◽  
Motion Detector
Sign in / Sign up

Export Citation Format

Share Document