Method and Apparatus for Acceleration of Dense MR Data Acquisition (Case No. 2025-226)

Summary:

UCLA researchers from the Department of Radiological Sciences have developed a novel acquisition and reconstruction strategy that accelerates Displacement Encoding with Stimulated Echoes (DENSE) MRI, enabling faster and clinically feasible cardiac strain measurement.

Background:

Myocardial strain is an important biomarker for assessing how the heart muscle stretches and contracts during each beat and serves as an early indicator of heart dysfunction. Advances in cardiac MRI have enabled precise visualization of strain patterns, and a specialized imaging technique called DENSE (Displacement Encoding with Stimulated Echoes) MRI allows direct measurement of small but critical heart muscle displacements. This method serves as a reliable diagnostic tool to assess strain and detect early signs of disease, enabling improved clinician insight and medical intervention. Despite its promise, DENSE MRI remains challenging for clinical use because data acquisition is relatively slow and typically requires patients to hold their breath for extended periods. Standard cine DENSE protocols often demand approximately 20 seconds of breath-holding, which can be difficult for elderly patients, or others with health complications. Reducing scan times and breath-hold demands in current state-of-the-art systems is essential to make DENSE MRI more practical and accessible for a broader patient population in routine clinical care. There remains a clear unmet need for an accelerated DENSE MRI acquisition approach that expands the feasibility of this technique across a wider range of patients and clinical applications.

Innovation:

UCLA researchers have developed a novel image acquisition and reconstruction strategy to accelerate DENSE MRI. Instead of acquiring the full dataset required for reconstruction, this method uses a unique undersampling scheme to reduce overall scan time while still ensuring a uniform data distribution for reconstruction. To address artifacts typically associated with undersampling, the approach incorporates compressed sensing reconstruction, which iteratively exploits redundancies within the acquired data to recover high-quality images. This combination enables efficient data sampling while preserving the accuracy of strain measurements.
In proof-of-concept studies on healthy volunteers, the accelerated protocol achieved up to 1.5-fold faster acquisition while maintaining accurate displacement and strain maps. This reduction in breath-hold duration improves patient comfort and feasibility without compromising image quality or measurement reliability. Moreover, the framework is compatible with additional acceleration methods and can be extended to 3D and 4D acquisitions for comprehensive cardiac strain analysis. By reducing both scan time and patient burden, this innovation has the potential to enhance the efficiency and clinical practicality of cardiac strain imaging, paving the way for broader adoption of advanced MRI in the management of heart dysfunction. 

Potential Applications:

•    Cardiac strain imaging in vulnerable patient populations (e.g., heart failure, cardiotoxicity)
•    Integration into routine cardiac MRI protocols to streamline workflows, increase scanner throughput, and improve clinical efficiency
•    Clinical trial support
•    Advanced motion analysis through extension to 3D and 4D DENSE MRI acquisitions
•    Research studies on myocardial mechanics in inherited, rare, or complex cardiac diseases

Advantages:

•    Reduced scan time and shortened breath-hold duration for improved patient tolerance and comfort
•    High measurement accuracy of displacement and strain measurements despite undersampling
•    Compatible with additional DENSE acceleration strategies 
•    Scalable to higher-dimensional DENSE acquisitions (3D/4D) for comprehensive strain analysis
•    Generalizable to other cardiac MRI sequences requiring acceleration 

State of Development:

The current prototype has been tested on five in vivo healthy volunteers’ cardiac datasets. This work was presented to 2025 Annual Meeting of the International Society for Magnetic Resonance in Medicine (ISMRM) in May 2025. 

Related Papers:
 

• Shih SF, Li S, Wu Y, Wang S, Han F, Wu HH, Nguyen KL, Finn JP, Zhong X. Accelerated 2D cine DENSE MRI using golden-angle spiral acquisition and compressed sensing reconstruction. Proc Intl Soc Mag Reson Med 33. 2025.
• Zhong X, Spottiswoode BS, Meyer CH, Kramer CM, Epstein FH. Imaging three-dimensional myocardial mechanics using navigator-gated volumetric spiral cine DENSE MRI. Magn Reson Med. 2010;64(4):1089–97.  
• Wehner GJ, Suever JD, Haggerty CM, Jing L, Powell DK, Hamlet SM, Grabau, J.D., Mojsejenko, W.D., Zhong, X., Epstein, F.H. and Fornwalt, B.K. Validation of in vivo 2D displacements from spiral cine DENSE at 3 T. J Cardiovasc Magn Reson. 2015;17(1):5.
• Spottiswoode BS, Zhong X, Lorenz CH, Mayosi BM, Meintjes EM, Epstein FH. Motion-guided segmentation for cine DENSE MRI. Med Image Anal. 2009;13(1):105–15.
• Spottiswoode BS, Zhong X, Hess AT, Kramer CM, Meintjes EM, Mayosi BM, Epstein FH. Tracking myocardial motion from cine DENSE images using spatiotemporal phase unwrapping and temporal fitting. IEEE Trans Med Imaging. 2007;26(1):15–30.

Reference:

UCLA CASE No. 2025-226

Lead Inventor:

Xiaodong Zhong, Department of Radiological Sciences