Tom Hilbert

True constructive interference in the steady state (trueCISS)

To introduce a novel time‐efficient method, termed true constructive interference in the steady state (trueCISS), that not only solves the problem of banding artifacts for balanced steady‐state free precession (bSSFP) but also provides its genuine, that is, true, on‐resonant signal.

Prospective head motion correction using FID-guided on-demand image navigators

We suggest a motion correction concept that employs free‐induction‐decay (FID) navigator signals to continuously monitor motion and to guide the acquisition of image navigators for prospective motion correction following motion detection.

An in vivo study of the orientation-dependent and independent components of transverse relaxation rates in white matter

Diffusion‐weighted imaging (DWI) provides information that allows the estimation of white‐matter (WM) fibre orientation and distribution, but it does not provide information about myelin density, fibre concentration or fibre size within each voxel. On the other hand, quantitative relaxation contrasts (like the apparent transverse relaxation, R2∗ ) offer iron and myelin‐related contrast, but their dependence on the orientation of microstructure with respect to the applied magnetic field, B0, is often neglected. The aim of this work was to combine the fibre orientation information retrieved from the DWI acquisition and the sensitivity to microstructural information from quantitative relaxation parameters. The in vivo measured quantitative transverse relaxation maps (R2 and R2∗ ) were decomposed into their orientation‐dependent and independent components, using the DWI fibre orientation information as prior knowledge.

Accelerated T2 mapping combining parallel MRI and model-based reconstruction: GRAPPATINI: Accelerated T2 Mapping

Quantitative T2 measurements are sensitive to intra‐ and extracellular water accumulation and myelin loss. Therefore, quantitative T2 promises to be a good biomarker of disease. However, T2 measurements require long acquisition times.

Clinical equivalence assessment of T2 synthesized pediatric brain magnetic resonance imaging

BACKGROUND AND PURPOSE Automated synthetic magnetic resonance imaging (MRI) provides qualitative, weighted image contrasts as well as quantitative information from one scan and is well-suited for various applications such as analysis of white matter disorders. However, the synthesized contrasts have been poorly evaluated in pediatric applications. The purpose of this study was to compare the image quality of synthetic T2 to conventional turbo spin-echo (TSE) T2 in pediatric brain MRI. MATERIALS AND METHODS This was a mono-center prospective study. Synthetic and conventional MRI acquisitions at 1.5 Tesla were performed for each patient during the same session using a prototype accelerated T2 mapping sequence package (TAsynthetic=3:07min, TAconventional=2:33min). Image sets were blindly and randomly analyzed by pediatric neuroradiologists. Global image quality, morphologic legibility of standard structures and artifacts were assessed using a 4-point Likert scale. Inter-observer kappa agreements were calculated. The capability of the synthesized contrasts and conventional TSE T2 to discern normal and pathologic cases was evaluated. RESULTS Sixty patients were included. The overall diagnostic quality of the synthesized contrasts was non-inferior to conventional imaging scale (P=0.06). There was no significant difference in the legibility of normal and pathological anatomic structures of synthetized and conventional TSE T2 (all P>0.05) as well as for artifacts except for phase encoding (P=0.008). Inter-observer agreement was good to almost perfect (kappa between 0.66 and 1). CONCLUSIONS T2 synthesized contrasts, which also provides quantitative T2 information that could be useful, could be suggested as an equivalent technique in pediatric neuro-imaging, compared to conventional TSE T2.