Free-Breathing Ungated Radial Simultaneous Multi-Slice Cardiac T1 Mapping.

Area of Science:

• Cardiovascular Magnetic Resonance Imaging
• Cardiac T1 Mapping
• Medical Imaging Technology

Background:

• Standard Modified Look-Locker imaging (MOLLI) T1 mapping requires breath-holding and ECG gating, posing challenges for patients with atrial fibrillation (AF).
• A need exists for free-breathing and ungated cardiac T1 mapping techniques to improve patient accessibility and data acquisition.

Purpose of the Study:

• To develop and evaluate a novel free-breathing, ungated radial simultaneous multi-slice (SMS) cardiac T1 mapping framework, termed FURST.
• To assess the performance and comparability of the FURST framework against conventional MOLLI sequences.

Main Methods:

• A retrospective cohort study involving 17 canine and 7 human subjects was conducted.
• Pre- and post-contrast T1 mapping was performed using both the FURST sequence and conventional MOLLI sequences at 1.5T and 3.0T.
• Analysis included segment-wise comparisons of T1 values and extracellular volume (ECV) using correlation and Bland-Altman plots, alongside reproducibility and image quality assessments (PIQUE).

Main Results:

• The FURST framework demonstrated no significant differences in pre-contrast T1, post-contrast T1, or ECV reproducibility compared to MOLLI.
• Image quality, assessed by PIQUE scores, was also comparable between FURST and MOLLI.
• The mean ECV difference between FURST and MOLLI was minimal ($$).

Conclusions:

• The developed free-breathing, ungated radial SMS (FURST) framework yields T1 and ECV maps of similar quality and reproducibility to MOLLI.
• FURST represents a promising alternative for cardiac T1 mapping, particularly beneficial for patients unable to perform breath-holds or with arrhythmias.