Publications by authors named "Simon Reichert"
Purpose: To develop a new sequence to simultaneously acquire Cartesian sodium (Na) MRI and accelerated Cartesian single (SQ) and triple quantum (TQ) sodium MRI of in vivo human brain at 7 T by leveraging two dedicated low-rank reconstruction frameworks.
Theory And Methods: The Double Half-Echo technique enables short echo time Cartesian Na MRI and acquires two k-space halves, reconstructed by a low-rank coupling constraint. Additionally, three-dimensional (3D) Na Multi-Quantum Coherences (MQC) MRI requires multi-echo sampling paired with phase-cycling, exhibiting a redundant multidimensional space.
Purpose: Sodium triple quantum (TQ) signal has been shown to be a valuable biomarker for cell viability. Despite its clinical potential, application of Sodium TQ signal is hindered by complex pulse sequences with long scan times. This study proposes a method to approximate the TQ signal using a single excitation pulse without phase cycling.
View Article and Find Full Text PDFPurpose: Both sodium T triple quantum (TQ) signal and T relaxation pathways have a unique sensitivity to the sodium molecular environment. In this study an inversion recovery time proportional phase increment (IRTQTPPI) pulse sequence was investigated for simultaneous and reliable quantification of sodium TQ signal and bi-exponential T relaxation times.
Methods: The IRTQTPPI sequence combines inversion recovery TQ filtering and time proportional phase increment.
Article Synopsis
- Sodium multi-quantum coherences (MQC) MRI was accelerated using a new five-dimensional compressed sensing framework, which supports simultaneous imaging at different quantum levels in the human brain.
- The study developed a joint reconstruction technique to enhance image quality by leveraging sparsity across multiple dimensions, resulting in significant reductions in error rates and improvements in similarity indices for sodium concentration mapping.
- The results highlighted a potential three-fold acceleration of scanning time at 3.0 T and a two-fold increase at 7.0 T, achieving high-resolution images without prolonging the acquisition time.