Fast high-resolution brain metabolite mapping on a clinical 3T MRI by accelerated 1 H-FID-MRSI and low-rank constrained reconstruction

Antoine Klauser , Sebastien Courvoisier , Jeffrey Kasten , Michel Kocher (1) , Matthieu Guerquin-Kern (2) , Dimitri van de Ville (3) , François Lazeyras (4)

1 EIG-HES (École d’Ingénieurs de Genève)
2 ETIS - UMR 8051 - Equipes Traitement de l'Information et Systèmes
3 Biomedical Imaging Group [Lausanne]
4 Department of Radiology

Purpose Epitomizing the advantages of ultra short echo time and no chemical shift displacement error, high-resolution free induction decay magnetic resonance spectroscopic imaging (FID-MRSI) sequences have proven to be highly effective in providing unbiased characterizations of metabolite distributions. However, its merits are often overshadowed in high-resolution settings by reduced signal-to-noise ratios resulting from the smaller voxel volumes procured by extensive phase encoding and the related acquisition times. Methods To address these limitations, we here propose an acquisition and reconstruction scheme that offers both implicit dataset denoising and acquisition acceleration. Specifically, a slice selective high-resolution FID-MRSI sequence was implemented. Spectroscopic datasets were processed to remove fat contamination, and then reconstructed using a total generalized variation (TGV) regularized low-rank model. We further measured reconstruction performance for random undersampled data to assess feasibility of a compressed-sensing SENSE acceleration scheme. Performance of the lipid suppression was assessed using an ad hoc phantom, while that of the low-rank TGV reconstruction model was benchmarked using simulated MRSI data. To assess real-world performance , 2D FID-MRSI acquisitions of the brain in healthy volunteers were reconstructed using the proposed framework. Results Results from the phantom and simulated data demonstrate that skull lipid contamination is effectively removed and that data reconstruction quality is improved with the low-rank TGV model. Also, we demonstrated that the presented acquisition and reconstruction methods are compatible with a compressed-sensing SENSE acceleration scheme. Conclusion An original reconstruction pipeline for 2D 1 H-FID-MRSI datasets was presented that places high-resolution metabolite mapping on 3T MR scanners within clinically feasible limits.

Domaines: Imagerie médicale; Imagerie; Traitement du signal et de l'image [eess.SP]

Antoine Klauser, Sebastien Courvoisier, Jeffrey Kasten, Michel Kocher, Matthieu Guerquin-Kern, et al.. Fast high-resolution brain metabolite mapping on a clinical 3T MRI by accelerated 1 H-FID-MRSI and low-rank constrained reconstruction. Magnetic Resonance in Medicine, 2018. ⟨hal-01960235⟩