Quantification of left ventricular functional parameter values using 3D spiral bSSFP and through-time Non-Cartesian GRAPPA

Abstract

BackgroundThe standard clinical acquisition for left ventricular functional parameter analysis with cardiovascular magnetic resonance (CMR) uses a multi-breathhold multi-slice segmented balanced SSFP sequence. Performing multiple long breathholds in quick succession for ventricular coverage in the short-axis orientation can lead to fatigue and is challenging in patients with severe cardiac or respiratory disorders. This study combines the encoding efficiency of a six-fold undersampled 3D stack of spirals balanced SSFP sequence with 3D through-time spiral GRAPPA parallel imaging reconstruction. This 3D spiral method requires only one breathhold to collect the dynamic data.MethodsTen healthy volunteers were recruited for imaging at 3 T. The 3D spiral technique was compared against 2D imaging in terms of systolic left ventricular functional parameter values (Bland-Altman plots), total scan time (Welch’s t-test) and qualitative image rating scores (Wilcoxon signed-rank test).ResultsSystolic left ventricular functional values were not significantly different (i.e. 3D-2D) between the methods. The 95% confidence interval for ejection fraction was −0.1 ± 1.6% (mean ± 1.96*SD). The total scan time for the 3D spiral technique was 48 s, which included one breathhold with an average duration of 14 s for the dynamic scan, plus 34 s to collect the calibration data under free-breathing conditions. The 2D method required an average of 5min40s for the same coverage of the left ventricle. The difference between 3D and 2D image rating scores was significantly different from zero (Wilcoxon signed-rank test, p < 0.05); however, the scores were at least 3 (i.e. average) or higher for 3D spiral imaging.ConclusionThe 3D through-time spiral GRAPPA method demonstrated equivalent systolic left ventricular functional parameter values, required significantly less total scan time and yielded acceptable image quality with respect to the 2D segmented multi-breathhold standard in this study. Moreover, the 3D spiral technique used just one breathhold for dynamic imaging, which is anticipated to reduce patient fatigue as part of the complete cardiac examination in future studies that include patients.Electronic supplementary materialThe online version of this article (doi:10.1186/s12968-014-0065-1) contains supplementary material, which is available to authorized users.

Free‐breathing cine imaging with motion‐corrected reconstruction at 3T using SPiral Acquisition with Respiratory correction and Cardiac Self‐gating (SPARCS)

“…This is partially compensated for in the SPARCS technique by using a longer TR and higher flip angles. Our group has previously demonstrated that SSFP‐based spiral imaging is also feasible at 1.5T, and a previous study showed that it could be performed at 3T . Compared with the ECG signal trigger, which always corresponds to the beginning of systole, the SPARCS extracted cardiac trigger can vary within the cardiac cycle.…”

Feasibility of through‐time spiral generalized autocalibrating partial parallel acquisition for low latency accelerated real‐time MRI of speech

“…With the known weights, it performs a frame‐by‐frame linear reconstruction to estimate the missing k‐space samples in every coil. Through‐time non‐Cartesian GRAPPA has been applied and evaluated in several dynamic and relaxometry MRI applications, including real‐time cardiac MRI , renal MRI angiography , liver perfusion MRI , and T 1 mapping . Here, we evaluate it to efficiently exploit the acceleration capabilities offered by a custom eight‐channel upper‐airway coil and spiral trajectories for dynamic upper‐airway imaging.…”

Single breath‐hold 3D cardiac T1 mapping using through‐time spiral GRAPPA

“…In this study, rapid 3D T 1 mapping was achieved by collecting accelerated spiral data and reconstructing images with through‐time spiral GRAPPA. This technique was originally proposed for free‐breathing 2D cardiac imaging, and has found widespread use in multiple 3D applications, including breath‐hold 3D cardiac perfusion imaging, free‐breathing whole‐liver perfusion imaging and 3D abdominal T 1 mapping . In this study, a 3D cardiac T 1 mapping technique was developed, which allows fast and accurate T 1 mapping of the heart in a single short breath‐hold.…”

“…In addition to the accelerated T 1 ‐weighted data, a 3D FLASH‐based calibration scan, consisting of four fully sampled 3D volumes (~10 s), was collected for use in the 3D through‐time spiral GRAPPA calibration step . For in vivo studies, this calibration scan was acquired during free breathing without ECG gating, as suggested in the literature …”