Figure 2. Pixelwise fMBV and water exchange maps in a swine model of regional myocardial hypoperfusion (a, b) and a normal swine subject (d, e). In the swine subject with artificially induced coronary stenosis (top panel), differences in fMBV (a) and water exchange (b) can be observed in the hypoperfused anterior, septal, and inferior segments. Angiographic image (c) acquired following deployment of a 3D printed coronary implant in the mid LAD shows severe coronary narrowing.

Figure 1. Ferumoxytol multi-dose T1 mapping study protocol. Following anesthesia and localizers, we acquired mid-ventricular short axis T1 maps at eight cumulative ferumoxytol doses (0.0 – 4.0 mg/kg). Following each ferumoxytol infusion, we observed a five-minute delay to achieve contrast steady state. MOLLI, Modified Look-Locker Inversion.

Table 1. Characteristics of the participants.

Figure 1. TRUST OEF data of representative normal (top row), MCI (second row) and demented (bottom row) subjects. Subtraction between control (first column) and labeled (second row) images yields strong venous blood signal in the superior sagittal sinus (yellow arrows) in the difference images (third column). The scatter plots on the far right show venous signal as a function of effective TE (eTE). Fitted venous blood T2 and the corresponding OEF values (before correction) are also shown.

Figure 2:

Fig 2A: Outline of initial steps in 3D-CaSM pipeline, from image acquisition to thickness measurement. Femur used for demonstration purposes – 3D-CaSM is also performed for tibial cartilage surfaces.

Fig 2B: Outline of cartilage composition measurement process. In this example, a T1rho map is used. Note focal area of increased T1rho values on the medial femoral condyle (black arrowhead) corresponding to an area of partial thickness cartilage loss on the 3D SPGR images (white arrowhead).

Figure 5: Implementation of 3D-CaSM in a clinical study of knee joint distraction using statistical parametric mapping to detect effects at group level. Surface data represent mean change from baseline mapped to the canonical surface and masked for statistical significance. Significant increases in cartilage thickness are seen over the weight-bearing medial femoral condyle at up to 5 years follow-up, with a delayed compensatory response in the lateral compartment at 7 years & 10 years follow-up.

Figure 3: Excitation selectivity and unaliasing quality of SMURF imaging demonstrated for one exemplary volunteer for each body region under consideration. The acquired aliased images show the overlapping water and fat images, which are CAIPIRINHA‐shifted along the phase‐encoding (PE) direction. Separate SMURF water and fat images, reconstructed from the aliased images, illustrate the achieved separation quality. (The separated images were rescaled for improved visibility.)

Figure 1: Fat‐water separation, chemical shift corrections, and recombination in Simultaneous Multiple Resonance Frequency (SMURF) imaging. Overlapping water and CAIPIRINHA‐shifted fat images are unaliased using slice‐GRAPPA (Step 1). The fat image is shifted to reverse chemical shift displacement – see the positions relative to the red reference line – and, for GRE acquisitions, corrected for chemical shift‐related phase evolution (Step 2). The fat and water images are then recombined (Step 3), generating a fat‐water image free of chemical shift artefacts.

Figure 1 (A) Schematic of an RF pulse followed by gradient waveform for EPI readout (FOV=128mm, 32x32 matrix, TE=28.4ms, readout=28.8ms) highlights the evolution of J-modulation during imaging. (B) k-space weighting due to J-modulation is significant in the slower phase encode direction (ky). (C) Spatial frequencies nulled due to J-coupling evolution during readout (Acq1), compensated by acquiring a quadrature component by delaying the acquisition time by 1/2J (Acq2). (D) Complex combination of these two quadrature components restores the original image, (E).

Figure 2 Narrowband excitation for resolving J-coupling induced doublet in [2-¹³C]Lac. Evolution of J-coupling during a short RF pulse (500μs, 2kHz bandwidth) is negligible and hence results in a doublet during signal collection (top row). A long narrow bandwidth pulse (13.33ms, 75Hz), J/2 Hz off-resonance (70Hz), on the other hand, generates in-phase and anti-phase coherences that combine to result in a singlet during signal acquisition.

Figure 2: Representative maps of kinetic parameters showing normal breast tissue from a 52-year-old healthy volunteer (A), a benign tumor (marked by a yellow solid boundary) from a 49-year-old patient (B), and a malignant tumor (marked by a red dashed boundary) from a 65-year-old patient (C). The gray-scale images display peak-enhanced LD-MT-DCE images and the standard-dose images at the same slice. The overlaid colormaps represents F_p, v_p, K^trans, and ve, respectively.

Figure 4: Mean and standard deviation measurements of F_p, v_p, K_trans, and ve for control group, and benign and malignant tumors in patient group. The P value of each pair by one-way ANOVA with Tukey test are marked on top of the bar graphs. F_p, v_p, and K_trans were significantly different between control and malignant tumor, and between benign and malignant tumors; F_p, and v_p were significantly different between control and benign tumors. * indicates statistically significant difference.