Reproducibility of magnetic resonance fingerprinting-based T1 mapping of the healthy prostate at 1.5 and 3.0 T: A proof-of-concept study

Abstract

Facilitating clinical translation of quantitative imaging techniques has been suggested as means of improving interobserver agreement and diagnostic accuracy of multiparametric magnetic resonance imaging (mpMRI) of the prostate. One such technique, magnetic resonance fingerprinting (MRF), has significant competitive advantages over conventional mapping techniques in terms of its multi-site reproducibility, short scanning time and inherent robustness to motion. It has also been shown to improve the detection of clinically significant prostate cancer when added to standard mpMRI sequences, however, the existing studies have all been conducted on 3.0 T MRI systems, limiting the technique’s use on 1.5 T MRI scanners that are still more widely used for prostate imaging across the globe. The aim of this proof-of-concept study was, therefore, to evaluate the cross-system reproducibility of prostate MRF T1 in healthy volunteers (HVs) using 1.5 and 3.0 T MRI systems. The initial validation of MRF T1 against gold standard inversion recovery fast spin echo (IR-FSE) T1 in the ISMRM/NIST MRI system revealed a strong linear correlation between phantom-derived MRF and IR-FSE T1 values was observed at both field strengths (R2 = 0.998 at 1.5T and R2 = 0.993 at 3T; p = < 0.0001 for both). In young HVs, inter-scanner CVs demonstrated marginal differences across all tissues with the highest difference of 3% observed in fat (2% at 1.5T vs 5% at 3T). At both field strengths, MRF T1 could confidently differentiate prostate peripheral zone from transition zone, which highlights the high quantitative potential of the technique given the known difficulty of tissue differentiation in this age group. The high cross-system reproducibility of MRF T1 relaxometry of the healthy prostate observed in this preliminary study, therefore, supports the technique’s prospective clinical validation as part of larger trials employing 1.5 T MRI systems, which are still widely used clinically for routine mpMRI of the prostate.

Multicenter Repeatability and Reproducibility of MR Fingerprinting in Phantoms and in Prostatic Tissue

“…MRF has been shown to provide highly reproducible quantitative maps in both 2D 14 and 3D 15 acquisitions. MRF‐derived T 1 and T 2 measurements are also repeatable over time, 16 with excellent reproducibility in vivo across different scanner types 17,18 . Several in vivo multicenter studies demonstrated high levels of repeatability and reproducibility of MRF in the brain 17,19 .…”

“…MRF-derived T 1 and T 2 measurements are also repeatable over time, 16 with excellent reproducibility in vivo across different scanner types. 17,18 Several in vivo multicenter studies demonstrated high levels of repeatability and reproducibility of MRF in the brain. 17,19 However, repeatability and reproducibility of the prostate MRF acquisition in phantom and prostatic tissues across different centers have not yet been demonstrated.…”

Magnetic Resonance Fingerprinting

“…The prostate MRF technique has been shown to have good intrascanner repeatability, although reproducibility across multiple different scanners has been shown to be slightly more variable but similar to other quantitative measures 9 . T1 and T2 values have also been shown to be reproducible with both 1.5 T and 3 T acquisition 99 . Continued assessment of reproducibility will enable creation of reliable normative quantitative data.…”

“…9 T1 and T2 values have also been shown to be reproducible with both 1.5 T and 3 T acquisition. 99 Continued assessment of reproducibility will enable creation of reliable normative quantitative data.…”

Current Applications and Future Development of Magnetic Resonance Fingerprinting in Diagnosis, Characterization, and Response Monitoring in Cancer

“…However, the consistent results obtained from separate independent preliminary trials are encouraging. High inter-scanner reproducibility of MRF T1 relaxometry was reported for assessing healthy prostate recently for both 1.5T and 3T MRI scanners [ 66 ]. Similar studies in patients with suspected prostate cancer have yet to report their findings.…”