Imaging experiments were performed on 1.5T clinical MRI systems (MAGNETOM Espree and MAGNETOM Avanto, Siemens AG Healthcare Sector, Erlangen, Germany) equipped with 32 receiver channels. All subjects were scanned at the National Heart, Lung and Blood Institute, Bethesda, Maryland, USA. This study was approved by the local Institutional Review Board, and written informed consent was given by all participants.
A total of 45 patients (23 men, 22 women; mean age 47.1±15.9 years) were imaged both before and after contrast injection. Typical sequence parameters are as following: inversion recovery prepared MOLLI with balanced SSFP readout, TR=2.4/TE=1.05ms, acquired matrix 192×126, reconstructed matrix size 192×144, flip angle 35°, in-plane spatial resolution 1.9×2.1mm2, rectangular FOV 360×270mm2, slice thickness 6mm, bandwidth 1000 Hz/pixel. 8 images were acquired with 11 heart beats using 2 inversions. All acquisitions were ECG-gated and breath-held.
For every patient, the MOLLI imaging was performed for at least 2 slices (mid-ventricular short axis and four chamber long axis views) for both pre- and post-contrast. The post-contrast acquisition was performed at approximated 15-20 minutes following the intravenous injection of Gd-DTPA at 0.15 mmol/kg dose. The entire data cohort consists of 180 MOLLI series (90/90 pre/post-contrast, 95/85 short/long axis).
The proposed workflow was implemented using C++. All computation was performed on a 64bit Window 7 workstation containing two quad-core Intel Xeon E5620 2.4GHz processers and 24GB RAM. Typical processing time of PSIR-MOCO and fitting was less than 5 seconds per slice, including initial motion correction, background phase removal, MOLLI image registration and pixel-wise PSIR T1 fitting. The computational time is measured by recording the processing time per MOLLI series and computing the mean and standard deviation for all series.
A total of 45 patients (23 men, 22 women; mean age 47.1±15.9 years) were imaged both before and after contrast injection. Typical sequence parameters are as following: inversion recovery prepared MOLLI with balanced SSFP readout, TR=2.4/TE=1.05ms, acquired matrix 192×126, reconstructed matrix size 192×144, flip angle 35°, in-plane spatial resolution 1.9×2.1mm2, rectangular FOV 360×270mm2, slice thickness 6mm, bandwidth 1000 Hz/pixel. 8 images were acquired with 11 heart beats using 2 inversions. All acquisitions were ECG-gated and breath-held.
For every patient, the MOLLI imaging was performed for at least 2 slices (mid-ventricular short axis and four chamber long axis views) for both pre- and post-contrast. The post-contrast acquisition was performed at approximated 15-20 minutes following the intravenous injection of Gd-DTPA at 0.15 mmol/kg dose. The entire data cohort consists of 180 MOLLI series (90/90 pre/post-contrast, 95/85 short/long axis).
The proposed workflow was implemented using C++. All computation was performed on a 64bit Window 7 workstation containing two quad-core Intel Xeon E5620 2.4GHz processers and 24GB RAM. Typical processing time of PSIR-MOCO and fitting was less than 5 seconds per slice, including initial motion correction, background phase removal, MOLLI image registration and pixel-wise PSIR T1 fitting. The computational time is measured by recording the processing time per MOLLI series and computing the mean and standard deviation for all series.
