Non-contrast MRI Myocardial Perfusion Analysis via Tag-on Tag-off Subtraction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current MRI techniques for myocardial perfusion analysis often require contrast agents, limiting their ability to distinguish between normal, ischemic, and infarct myocardium without causing stress, and lack the capability for three-dimensional coverage and perfusion curve generation.
Innovation Solution
A non-contrast MRI method using tag-on and tag-off data acquisition sequences with spatially selective RF pulses and complex-valued arithmetic for pixel-by-pixel subtraction, enabling the creation of blood perfusion images and perfusion curves without injected contrast agents, allowing differentiation between normal, ischemic, and infarct myocardium.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If contrast agents are used for myocardial perfusion analysis, then the ability to distinguish between normal, ischemic, and infarct myocardium is improved, but the safety and patient comfort deteriorate due to stress induction and potential adverse effects
Solution Approach 1:
The patent extracts and eliminates the contrast agent component from the perfusion imaging system. By using native tissue signal characteristics and time-dependent signal evolution rather than exogenous contrast agents, the method removes the harmful factors associated with contrast administration while maintaining the ability to differentiate myocardial perfusion states through intrinsic tissue properties
Solution Approach 2:
The method enables the myocardium to serve itself as the contrast source by utilizing its own perfusion characteristics. The blood pool and myocardial tissue generate intrinsic signal differences based on their perfusion status, eliminating the need for external contrast agents. The system uses the body's own physiological processes to create the necessary signal differentiation
2Loss of time
If two-dimensional perfusion imaging is used, then the imaging time is reduced, but the coverage and diagnostic information deteriorate due to lack of three-dimensional assessment
Solution Approach 1:
The patent employs periodic data acquisition across multiple cardiac cycles and time points. By systematically acquiring images at different time intervals and combining them through time-dependent signal processing, the method achieves comprehensive three-dimensional coverage of the myocardium while maintaining efficient imaging timing through the periodic nature of cardiac function
Solution Approach 2:
The method transitions from two-dimensional spatial imaging to three-dimensional assessment by adding the time dimension as a fourth parameter. Through time-dependent signal evolution and multi-temporal data acquisition, the system reconstructs comprehensive three-dimensional myocardial perfusion information, effectively using time as an additional dimension to achieve volumetric coverage
3Measurement precision
If detailed perfusion analysis is performed, then the diagnostic accuracy is improved, but the data processing complexity and time increase
Solution Approach 1:
The patent performs preliminary organization and structuring of the acquired data during the imaging process itself. By pre-processing the time-dependent signal data and organizing it according to spatial locations and time points, the system reduces the complexity of subsequent analysis while maintaining detailed perfusion assessment capabilities through structured data preparation
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
Enables the visualization and quantification of myocardial perfusion without contrast agents, distinguishing between healthy and abnormal myocardial regions, including revascularized areas, and provides three-dimensional coverage and perfusion curve generation.
Implementation Method 1
multi-slice non-contrast magnetic resonance (MR) images of left ventricle (LV) myocardium
Implementation Method 2
complex-valued arithmetic for pixel-by-pixel subtraction
Data Source
AI summary
Black blood time to inversion (BBTI) tag-on and tag-off images acquired by magnetic resonance imaging (MRI) are analyzed to produce difference magnitude 3D images as a function of time (BBTI values) representing blood perfusion in a region of interest (ROI). Perfusion data of the ROI having values which are different for normal and abnormal myocardial tissues are displayed for plural slices of a 3D image and for plural BBTI values in a single display panel.