Cardiac thrombus: can T1 and T2 mapping replace contrast enhanced images?

Area of Science:

• Cardiovascular MRI
• Medical Imaging Analysis

Background:

• Cardiac thrombus detection is crucial for stroke prevention.
• Contrast-enhanced MRI is the current standard for thrombus visualization.
• T1 and T2 mapping sequences offer potential non-contrast alternatives.

Purpose of the Study:

• To compare the diagnostic performance of T1/T2 mapping sequences versus contrast-enhanced MRI for cardiac thrombus detection.
• To evaluate signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) for thrombus visualization.

Main Methods:

• Retrospective analysis of MRI scans from 22 patients with cardiac thrombus.
• Quantitative assessment of SNR and CNR for thrombus, blood pool, and myocardium.
• Comparison of values obtained from T1 maps, T2 maps, and contrast-enhanced images (early and late gadolinium).

Main Results:

• Distinguishability of thrombus from surrounding tissues was superior on early (EGE) and late gadolinium-enhanced (LGE) images compared to T1 and T2 maps.
• Mean CNRs were highest for EGE, followed by LGE, and then mapping sequences.
• CNR values for EGE and LGE consistently outperformed mapping sequences.

Conclusions:

• Contrast-enhanced MRI remains the superior method for cardiac thrombus detection.
• Native mapping sequences show promise but are currently less effective than contrast imaging.
• Further research is needed to optimize non-contrast mapping techniques for thrombus evaluation.