Temporal 3D Lagrangian strain from 2D slice-followed cine DENSE MRI

Area of Science:

• Cardiovascular Imaging
• Biomedical Engineering
• Medical Physics

Background:

• Quantitative myocardial mechanics analysis is crucial for understanding cardiac function, diagnosing heart disease, and evaluating treatment efficacy.
• Current clinical practice relies heavily on 2D cardiac imaging due to time constraints, limiting the comprehensive assessment of cardiac mechanics.
• 2D measurements provide insufficient information for a complete understanding of the heart's complex mechanical behavior.

Purpose of the Study:

• To develop and validate a method for deriving transmural 3D Lagrangian strains from two intersecting 2D planes of displacement encoding with stimulated echoes (DENSE) data.
• To enable accurate, time-resolved quantification of myocardial mechanics even with limited scan times.
• To provide a more comprehensive assessment of cardiac function than traditional 2D methods.

Main Methods:

• Utilized a bilinear-cubic polynomial element to resolve strain from displaced myocardial positions derived from two 2D DENSE MRI slices.
• Employed slice-following cine DENSE sequences to capture myocardial motion.
• Validated the method against an analytical standard and applied it to in vivo data from a healthy volunteer.

Main Results:

• The method accurately calculated temporal evolutions of transmural 3D Lagrangian strains.
• Validation against an analytical model demonstrated high accuracy.
• In vivo application on a 3T MRI system yielded results consistent with published literature values for systolic strains in the left ventricular myocardium.

Conclusions:

• The developed method successfully reconstructs the full 3D Lagrangian strain tensor from two 2D DENSE measurements.
• This approach offers accurate myocardial strain quantification, overcoming the limitations of 2D imaging within practical scan times.
• The technique holds significant potential for improving cardiac function assessment, disease diagnosis, and therapeutic monitoring.