A 3D, non-ECG-gated, free-breathing T2* mapping technique reduced scan time by 2-3-fold compared to conventional methods while improving image quality and reducing artifacts.
Does a 3D, non-ECG-gated, free-breathing T2* mapping technique improve image quality and reduce scan time compared to conventional 2D T2* mapping in healthy humans and swine?
A novel 3D, non-ECG-gated, free-breathing T2* mapping technique significantly reduces scan time and motion artifacts, potentially improving cardiac MRI in patients with arrhythmias or limited breath-holding capacity.
Abstract Purpose Widely used conventional 2D T 2 * approaches that are based on breath‐held, electrocardiogram (ECG)–gated, multi‐gradient‐echo sequences are prone to motion artifacts in the presence of incomplete breath holding or arrhythmias, which is common in cardiac patients. To address these limitations, a 3D, non‐ECG‐gated, free‐breathing T 2 * technique that enables rapid whole‐heart coverage was developed and validated. Methods A continuous random Gaussian 3D k‐space sampling was implemented using a low‐rank tensor framework for motion‐resolved 3D T 2 * imaging. This approach was tested in healthy human volunteers and in swine before and after intravenous administration of ferumoxytol. Results Spatial‐resolution matched T 2 * images were acquired with 2–3‐fold reduction in scan time using the proposed T 2 * mapping approach relative to conventional T 2 * mapping. Compared with the conventional approach, T 2 * images acquired with the proposed method demonstrated reduced off‐resonance and flow artifacts, leading to higher image quality and lower coefficient of variation in T 2 *‐weighted images of the myocardium of swine and humans. Mean myocardial T 2 * values determined using the proposed and conventional approaches were highly correlated and showed minimal bias. Conclusion The proposed non‐ECG‐gated, free‐breathing, 3D T 2 * imaging approach can be performed within 5 min or less. It can overcome critical image artifacts from undesirable cardiac and respiratory motion and bulk off‐resonance shifts at the heart–lung interface. The proposed approach is expected to facilitate faster and improved cardiac T 2 * mapping in those with limited breath‐holding capacity or arrhythmias.
Guan et al. (Thu,) conducted a other in Healthy volunteers and swine. 3D, non-ECG-gated, free-breathing T2* mapping vs. Conventional 2D breath-held, ECG-gated T2* mapping was evaluated on Scan time, image quality, and mean myocardial T2* values. A 3D, non-ECG-gated, free-breathing T2* mapping technique reduced scan time by 2-3-fold compared to conventional methods while improving image quality and reducing artifacts.