Quantitative planar imaging method for measurement of renal activity by using a conjugate-emission image and transmission data

In this study, functional magnetic resonance image (fMRI)-compatible movement measurement system was developed. The movement measurement system consisted of a sensor module with a three-axis accelerometer and a two-axis gyroscope, a modulator, and a demodulator. Velcro was used to attach the sensor module to a finger or wrist. Interactive effects in a human subject were tested by measuring fMRI and motion signals simultaneously. Images were obtained using the field echo planar imaging method using a 3 T MR scanner and the signal-to-noise ratio was calculated. The entire system can be made with low cost, and its direct implementation is available in a clinical MR scanner without any additional installation. Various kinematic variables, such as angle, acceleration, and jerk, can be measured and calculated by using the movement measurement system. Therefore, it is expected that this system could be used for the study of the relationship between various kinematic variables and brain function.

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A high temporal/spatial resolution neuro-architecture study of rodent brain by wideband echo planar imaging

Scientific Reports ◽

10.1038/s41598-021-98132-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Po-Wei Cheng ◽

Tzi-Dar Chiueh ◽

Jyh-Horng Chen

Keyword(s):

Parallel Imaging ◽

Diffusion Tensor ◽

Echo Planar Imaging ◽

Imaging Method ◽

Planar Imaging ◽

Time Saving ◽

Scan Time ◽

Saving Effect ◽

Echo Planar ◽

Array Coils

AbstractLatest simultaneous multi-slice (SMS) methods greatly benefit MR efficiency for recent studies using parallel imaging technique. However, these methods are limited by the requirement of array coils. The proposed Coherent Wideband method, which employs an extended field of view to separate multiple excited slices, can be applied to any existing MRI instrument, even those without array coils. In this study, the Coherent Wideband echo-planar imaging method was implemented on 7 T animal MRI to exhibit comprehensive enhancements in neuro-architecture, including diffusion tensor imaging (DTI) and functional MR studies (fMRI). Under the same scan time, the time-saving effect can be manipulated to increase the number of averages for DTI SNR improvement, reducing fractional anisotropy difference by 56.9% (from 0.072 to 0.041) and the deviation angle by 64% (from 25.3° to 16.2°). In summary, Coherent Wideband Echo Planar Imaging (EPI) will provide faster, higher resolution, thinner slice, or higher SNR imaging for precision neuro-architecture studies.

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Wideband MR Echo Planar Imaging: A High Temporal/Spatial Resolution Neuro-architecture study of Rodent Brain

10.21203/rs.3.rs-413062/v1 ◽

2021 ◽

Author(s):

Po-Wei Cheng ◽

Tzi-Dar Chiueh ◽

Jyh-Horng Chen

Keyword(s):

Parallel Imaging ◽

Diffusion Tensor ◽

Echo Planar Imaging ◽

Imaging Method ◽

Planar Imaging ◽

Time Saving ◽

Scan Time ◽

Saving Effect ◽

Echo Planar ◽

Array Coils

Abstract Latest simultaneous multi-slice (SMS) methods greatly benefit MR efficiency for recent studies using parallel imaging technique. However, these methods are limited by the requirement of array coils. The proposed Coherent Wideband method, which employs an extended field of view to separate multiple excited slices, can be applied to any existing MRI instrument, even those without array coils. In this study, the Coherent Wideband echo-planar imaging method was implemented on 7T animal MRI to exhibit comprehensive enhancements in neuro-architecture, including diffusion tensor imaging (DTI) and functional MR studies (fMRI). Under the same scan time, the time-saving effect can be manipulated to increase the number of averages for DTI SNR improvement, reducing fractional anisotropy difference by 56.9% (from 0.072 to 0.041) and the deviation angle by 64% (from 25.3⁰ to 16.2⁰). In summary, Coherent Wideband EPI will provide faster, higher resolution, thinner slice, or higher SNR imaging for precision neuro-architecture studies.

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Wideband MR Echo Planar Imaging: A High Temporal/Spatial Resolution Neuro-architecture Study of Rodent Brain

10.21203/rs.3.rs-413062/v2 ◽

2021 ◽

Author(s):

Po-Wei Cheng ◽

Tzi-Dar Chiueh ◽

Jyh-Horng Chen

Keyword(s):

Parallel Imaging ◽

Diffusion Tensor ◽

Echo Planar Imaging ◽

Imaging Method ◽

Planar Imaging ◽

Time Saving ◽

Scan Time ◽

Saving Effect ◽

Echo Planar ◽

Array Coils

Abstract Latest simultaneous multi-slice (SMS) methods greatly benefit MR efficiency for recent studies using parallel imaging technique. However, these methods are limited by the requirement of array coils. The proposed Coherent Wideband method, which employs an extended field of view to separate multiple excited slices, can be applied to any existing MRI instrument, even those without array coils. In this study, the Coherent Wideband echo-planar imaging method was implemented on 7T animal MRI to exhibit comprehensive enhancements in neuro-architecture, including diffusion tensor imaging (DTI) and functional MR studies (fMRI). Under the same scan time, the time-saving effect can be manipulated to increase the number of averages for DTI SNR improvement, reducing fractional anisotropy difference by 56.9% (from 0.072 to 0.041) and the deviation angle by 64% (from 25.3⁰ to 16.2⁰). In summary, Coherent Wideband EPI will provide faster, higher resolution, thinner slice, or higher SNR imaging for precision neuro-architecture studies.

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Weak Beam Imaging and Diffraction Studies of Stacking Faults in Silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100092918 ◽

1976 ◽

Vol 34 ◽

pp. 590-591

Author(s):

T. Y. Tan ◽

W. K. Tice

Keyword(s):

Fast Neutron ◽

Rapid Determination ◽

Stacking Faults ◽

Imaging Method ◽

Large Reduction ◽

Dislocation Loops ◽

Fringe Spacing ◽

Weak Beam ◽

Kinematical Theory

In studying ion implanted semiconductors and fast neutron irradiated metals, the need for characterizing small dislocation loops having diameters of a few hundred angstrom units usually arises. The weak beam imaging method is a powerful technique for analyzing these loops. Because of the large reduction in stacking fault (SF) fringe spacing at large sg, this method allows for a rapid determination of whether the loop is faulted, and, hence, whether it is a perfect or a Frank partial loop. This method was first used by Bicknell to image small faulted loops in boron implanted silicon. He explained the fringe spacing by kinematical theory, i.e., ≃l/(Sg) in the fault fringe in depth oscillation. The fault image contrast formation mechanism is, however, really more complicated.

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Performance and applications of the holography electron microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100151222 ◽

1993 ◽

Vol 51 ◽

pp. 1078-1079

Author(s):

Akira Tonomura

Keyword(s):

Electron Beam ◽

Electron Microscope ◽

Phase Measurement ◽

Electron Holography ◽

Imaging Method ◽

High Contrast ◽

Magnetic Lens ◽

High Brightness ◽

Holographic Imaging ◽

Dynamic Observation

Electron holography is a two-step imaging method. However, the ultimate performance of holographic imaging is mainly determined by the brightness of the electron beam used in the hologram-formation process. In our 350kV holography electron microscope (see Fig. 1), the decrease in the inherently high brightness of field-emitted electrons is minimized by superposing a magnetic lens in the gun, for a resulting value of 2 × 109 A/cm2 sr. This high brightness has lead to the following distinguished features. The minimum spacing (d) of carrier fringes is d = 0.09 Å, thus allowing a reconstructed image with a resolution, at least in principle, as high as 3d=0.3 Å. The precision in phase measurement can be as high as 2π/100, since the position of fringes can be known precisely from a high-contrast hologram formed under highly collimated illumination. Dynamic observation becomes possible because the current density is high.

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