Combined acquisition of diffusion and T2*-weighted measurements using simultaneous multi-contrast magnetic resonance imaging

Abstract

Object In this work, we present a technique called simultaneous multi-contrast imaging (SMC) to acquire multiple contrasts within a single measurement. Simultaneous multi-slice imaging (SMS) shortens scan time by allowing the repetition time (TR) to be reduced for a given number of slices. SMC imaging preserves TR, while combining different scan types into a single acquisition. This technique offers new opportunities in clinical protocols where examination time is a critical factor and multiple image contrasts must be acquired. Materials and methods High-resolution, navigator-corrected, diffusion-weighted imaging was performed simultaneously with T2*-weighted acquisition at 3 T in a phantom and in five healthy subjects using an adapted readout-segmented EPI sequence (rs-EPI). Results The results demonstrated that simultaneous acquisition of two contrasts (here diffusion-weighted imaging and T2*-weighting) with SMC imaging is feasible with robust separation of contrasts and minimal effect on image quality. Discussion The simultaneous acquisition of multiple contrasts reduces the overall examination time and there is an inherent registration between contrasts. By using the results of this study to control saturation effects in SMC, the method enables rapid acquisition of distortion-matched and well-registered diffusion-weighted and T2*-weighted imaging, which could support rapid diagnosis and treatment of acute stroke.

2.5-Minute Fast Brain MRI with Multiple Contrasts in Acute Ischemic Stroke

“…However, it is not possible to synthesize DWI or SWI/T2* from the model-based parametric maps, currently limiting their application in stroke. A pulse sequence able to simultaneously acquire DWI and T2* contrasts has been developed [ 33 ], but this technique does not include T2-FLAIR. Deep-learning algorithms that generate synthetic T2-FLAIR from DWI with a time reduction of the MRI protocol have shown similar diagnostic performance to T2-FLAIR [ 34 ].…”

The role of medical physicists in clinical trials across Europe

“…New technology plays a major role in the advancement of clinical trials and MPs are required to be aware of major technology developments in both imaging and therapeutic settings. This encompasses but is not limited to large axial field-of-view PET [32], photon counting CT [33], organ/tissue specific gamma cameras [34][35][36], simultaneous multi-contrast MRI [37,38], identification of new biomarkers [39,40], automated treatment planning [41], adaptive RT [42,43], SRS/SRT/ SABR [44,45], MRI guided radiotherapy [46], particle therapies [47], flash radiotherapy, new hypofractionated schemes and relevant radiobiology [48]. Additionally, advances in artificial intelligence in almost all clinical phases of imaging and therapy require MPs to have detailed awareness of its routine capabilities and limitations.…”

Blood–Brain Barrier Permeability to Water Measured Using Multiple Echo Time Arterial Spin Labeling MRI in the Aging Human Brain

“…To fully utilize the potential of Hadamard imaging, a sequence with subject-specific optimization of sampling times can be used. One such method has been recently proposed, 37 where the sequence adapts to find optimal timings by analyzing intermediate images and adjusts bolus durations without the penalty of increase in the scan time. Such emerging methods offer a possibility to test subject-specific imaging which could ensure capturing meaningful information at every time point for every individual subject.…”