Finite State Machine Respiratory Phase Detection in MRI
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing magnetic resonance imaging (MRI) techniques face challenges in accurately capturing respiratory data due to varying respiratory movements during scans, leading to artifacts and inefficiencies in image reconstruction, particularly when using navigators for phase determination.
Innovation Solution
A method employing a finite state machine to determine the respiratory phase from a series of measurements, allowing for continuous adjustment of imaging data acquisition based on both respiratory position and phase, thereby reducing noise and improving data consistency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If respiratory gating is used to reduce artifacts from respiratory movement, then image quality is improved, but measurement time increases
Solution Approach 1:
The patent implements dynamic respiratory phase determination using a finite state machine that continuously processes navigator echo data to identify respiratory phases. This dynamic approach allows the system to adapt to varying respiratory patterns in real-time, enabling more efficient data acquisition by selectively acquiring imaging data only during appropriate respiratory phases, thereby reducing total measurement time while maintaining image quality.
Solution Approach 2:
The system changes the parameter of respiratory phase detection from static threshold-based methods to dynamic finite state machine processing. By processing a series of respiratory position measurements through state transitions, the system can more accurately determine respiratory phases and make informed decisions about data acquisition timing, optimizing the balance between image quality and measurement duration.
2Measurement precision
If navigator sequences are used to determine respiratory position, then respiratory monitoring is improved, but temporal scanning rate is reduced
Solution Approach 1:
The patent extracts respiratory position information from navigator echo data that is already acquired as part of the imaging sequence. By processing this existing data through a finite state machine to determine respiratory phases, the system avoids the need for additional dedicated navigator sequences, thereby maintaining temporal scanning rate while still achieving precise respiratory monitoring.
Solution Approach 2:
The navigator echoes serve multiple functions: they provide T2* weighting for tissue characterization and simultaneously enable respiratory phase determination through the finite state machine. This multi-functionality eliminates the need for separate respiratory monitoring sequences, preserving the temporal scanning rate while achieving both tissue characterization and respiratory tracking.
3Reliability
If respiratory phase determination is added to improve data selection, then artifact reduction is improved, but processing complexity increases
Solution Approach 1:
The finite state machine implements feedback by continuously processing respiratory position measurements and using the determined respiratory phase to control data acquisition decisions. This feedback mechanism enables real-time artifact reduction by selecting only data acquired during appropriate respiratory phases, while the state machine structure keeps processing complexity manageable through defined state transitions rather than complex algorithms.
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 enables more precise respiratory phase determination, reducing artifacts and improving the efficiency of MRI scans by accounting for both respiratory position and phase, leading to higher quality image reconstruction.
Implementation Method 1
the examination subject is placed in a magnetic resonance imaging scanner, in a strong, static, homogenous base magnetic field, also called a B0 field, having a field strength of 0.2 tesla-7 tesla and more, such that the nuclear spins of the subject orient themselves along the base magnetic field
Implementation Method 2
In order to trigger magnetic resonance signals, the examination subject is irradiated with high frequency excitation pulses (RF pulses), the triggered magnetic resonance signals are detected
Implementation Method 3
For the spatial encoding of the measurement data, rapidly activated magnetic gradient fields are superimposed on the base magnetic field
Data Source
AI summary
In a method for determining a respiratory phase from a series of measurements of a respiratory position, the respiratory phase is determined by a finite state machine, which processes a current measured respiratory position and at least one previously measured respiratory position, and assigns a current respiratory phase to the current respiratory position. For this purpose, the temporal spacing between two successive measurements of the respiratory position is small in relation to a respiratory cycle. This method allows for a continuous measurement of imaging measurement data to be influenced in a prospective manner in a determined respiratory phase.