MRI Coil Switching for Sensitivity Distribution Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current MRI techniques face challenges in accurately measuring sensitivity distribution of reception coils due to object displacement during imaging, leading to artifacts and reduced image quality, especially in parallel imaging and shading correction methods.
Innovation Solution
The MRI apparatus simultaneously switches between a whole-body coil and a specified coil for each echo in the same encode step, allowing for nearly simultaneous data acquisition from both coils, which reduces the impact of object displacement and enables accurate sensitivity distribution calculation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If imaging is executed separately in rotation for both specified coil and wide-range coil, then sensitivity distribution can be calculated, but object displacement between imaging executions causes errors in sensitivity distribution and generates artifacts
Solution Approach 1:
The patent combines the imaging processes of the specified coil and wide-range coil into a single simultaneous imaging execution, rather than performing them separately in rotation. This merging eliminates the time gap between imaging executions, preventing object displacement from causing sensitivity distribution calculation errors and artifacts.
Solution Approach 2:
The patent implements continuous data acquisition from both coils simultaneously during the same imaging execution, ensuring uninterrupted and synchronized measurement. This continuous simultaneous action maintains the spatial and temporal correspondence between the two coil datasets, eliminating errors caused by object movement during sequential imaging.
2Measurement precision
If imaging takes several seconds to several tens of seconds, then sensitivity distribution can be measured, but object displacement during imaging causes artifacts and image errors
Solution Approach 1:
The patent implements continuous simultaneous data acquisition from both coils during the same imaging execution, ensuring uninterrupted and synchronized measurement. This continuous simultaneous action maintains the spatial and temporal correspondence between the two coil datasets, eliminating errors caused by object movement during sequential imaging.
3Measurement precision
If one echo is received by both whole-body coil and array-coil by dividing sampling periods, then sensitivity distribution can be measured, but extremely high-speed coil switching is required which is difficult to implement with current apparatuses
Solution Approach 1:
The patent combines the imaging processes of the specified coil and wide-range coil into a single simultaneous imaging execution, rather than performing them separately in rotation. This merging eliminates the time gap between imaging executions, preventing object displacement from causing sensitivity distribution calculation errors and artifacts.
4Measurement precision
If measurement time for one echo is prolonged to receive signals from two coils, then both coils can measure one echo, but echo signal attenuation occurs during measurement
Solution Approach 1:
The patent combines the imaging processes of the specified coil and wide-range coil into a single simultaneous imaging execution, rather than performing them separately in rotation. This merging eliminates the time gap between imaging executions, preventing object displacement from causing sensitivity distribution calculation errors and artifacts.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach significantly reduces artifacts caused by object movement, enabling precise sensitivity distribution measurement and improved image quality by ensuring that data from both coils is acquired simultaneously, thus minimizing positional displacement errors.
Implementation Method 1
static magnetic field generation means for generating a static magnetic field
Implementation Method 2
gradient magnetic field generation means for generating gradient in the static magnetic field generated by the static magnetic field generation means
Implementation Method 3
high-frequency magnetic field transmission means for applying a high-frequency magnetic field to an examination target placed in a static magnetic field
Implementation Method 4
reception means for receiving a nuclear magnetic resonance signal generated from the examination target
Data Source
AI summary
When imaging for sensitivity distribution measurement is performed, a whole-body coil for both transmission and reception and a specified coil used for the present imaging are used as a reception coil, while being switched.The switching of the reception coil is performed by switching between the whole-body coil and the specified coil for each echo in the same encode step.An image created from the echo obtained by the specified coil is divided by an image created from the echo obtained by the whole-body coil to calculate the sensitivity distribution of the specified coil.The sets of data used for the calculation are almost simultaneously obtained, thus providing accurate sensitivity distribution with no influence derived from the movement of a subject.The sensitivity distribution is used to correct the image obtained by the present imaging.Alternatively, the sensitivity distribution is used for the folding operation of parallel imaging.