• Rajiv G Menon, Marcelo V W Zibetti, Rajan Jain, Yulin Ge, and Ravinder R Regatte.
• Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine, New York, New York, USA.
• J Magn Reson Imaging. 2021 Apr 1; 53 (4): 1130-1139.

Background3D-T1ρ mapping is useful to quantify various neurologic disorders, but data are currently time-consuming to acquire.PurposeTo compare the performance of five compressed sensing (CS) algorithms-spatiotemporal finite differences (STFD), exponential dictionary (EXP), 3D-wavelet transform (WAV), low-rank (LOW) and low-rank plus sparse model with spatial finite differences (L + S SFD)-for 3D-T1ρ mapping of the human brain with acceleration factors (AFs) of 2, 5, and 10.Study TypeRetrospective.SubjectsEight healthy volunteers underwent T1ρ imaging of the whole brain.Field Strength/SequenceThe sequence was fully sampled 3D Cartesian ultrafast gradient echo sequence with a customized T1ρ preparation module on a clinical 3T scanner.AssessmentThe fully sampled data was undersampled by factors of 2, 5, and 10 and reconstructed with the five CS algorithms. Image reconstruction quality was evaluated and compared to the SENSE reconstruction of the fully sampled data (reference) and T1ρ estimation errors were assessed as a function of AF.Statistical TestsNormalized root mean squared errors (nRMSE) and median normalized absolute deviation (MNAD) errors were calculated to compare image reconstruction errors and T1ρ estimation errors, respectively. Linear regression plots, Bland-Altman plots, and Pearson correlation coefficients (CC) are shown.ResultsFor image reconstruction quality, at AF = 2, EXP transforms had the lowest mRMSE (1.56%). At higher AF values, STFD performed better, with the smallest errors (3.16% at AF = 5, 4.32% at AF = 10). For whole-brain quantitative T1ρ mapping, at AF = 2, EXP performed best (MNAD error = 1.62%). At higher AF values (AF = 5, 10), the STFD technique had the least errors (2.96% at AF = 5, 4.24% at AF = 10) and the smallest variance from the reference T1ρ estimates.Data ConclusionThis study demonstrates the use of different CS algorithms that may be useful in reducing the scan time required to perform volumetric T1ρ mapping of the brain.Level Of Evidence2.Technical Efficacy Stage1.© 2020 International Society for Magnetic Resonance in Medicine.

13 keywords...

hide…