Abstract MRI using receiver arrays with many coil elements can provide high signal‐to‐noise ratio and increase parallel imaging acceleration. At the same time, growing number of results in larger datasets more computation reconstruction. This is particular concern 3D acquisitions iterative reconstructions. Coil compression algorithms are effective mitigating this problem by compressing data from channels into fewer virtual coils. In Cartesian sampling there often fully sampled k ‐space...

Purpose To develop and assess motion correction techniques for high-resolution pediatric abdominal volumetric magnetic resonance images acquired free-breathing with high scan efficiency. Materials Methods First, variable-density sampling radial-like phase-encode ordering were incorporated into the 3D Cartesian acquisition. Second, intrinsic multichannel butterfly navigators used to measure respiratory motion. Lastly, these estimates are applied both motion-weighted data-consistency in a...

Purpose To develop and evaluate motion‐compensation compressed‐sensing techniques in 4D flow MRI for anatomical assessment a comprehensive ferumoxytol‐enhanced congenital heart disease (CHD) exam. Materials Methods A Cartesian sequence was developed to enable intrinsic navigation two variable‐density sampling schemes: VDPoisson VDRad. Four methods were developed: A) scan reconstructed using spatial wavelets; B) added temporal total variation A; C) VDRad the same reconstruction as B; D)...

Purpose To develop a method for fast pediatric 3D free‐breathing abdominal dynamic contrast enhanced (DCE) magnetic resonance imaging (MRI) and investigate its clinical feasibility. Materials Methods A combined locally low rank parallel with soft gating is proposed DCE MRI acquisition. With Institutional Review Board (IRB) approval informed consent/assent, 23 consecutive patients were recruited this study. Free‐breathing ∼1 mm 3 spatial resolution 6.5‐sec frame rate was acquired on 3T...

Abstract Purpose: To evaluate the precision and accuracy of parallel‐imaging compressed‐sensing 4D phase contrast (PICS‐4DPC) magnetic resonance imaging (MRI) venous flow quantification in children with patients referred for cardiac MRI at our children's hospital. Materials Methods: With Institutional Review Board (IRB) approval Health Insurance Portability Accountability Act (HIPAA) compliance, 22 consecutive without shunts underwent 4DPC as part clinical examinations. Flow measurements...

Purpose To rapidly obtain high resolution T 2 , *, and quantitative susceptibility mapping (QSM) source separation maps with whole‐brain coverage geometric fidelity. Methods We propose Blip Up‐Down Acquisition for Spin And Gradient Echo imaging (BUDA‐SAGE), an efficient EPI sequence mapping. The acquisition includes multiple *‐, ′‐, ‐weighted contrasts. alternate the phase‐encoding polarities across interleaved shots in this multi‐shot navigator‐free acquisition. A field map estimated from...

Simultaneous Multi-Slice (SMS) magnetic resonance imaging (MRI) is a rapidly evolving technique for increasing speed. Controlled aliasing techniques utilize periodic undersampling patterns to help mitigate the loss in signal-to-noise ratio (SNR) SMS MRI. To evaluate performance of different patterns, quantitative description image SNR needed. Additionally, eddy current effects echo planar (EPI) lead slice-specific Nyquist ghosting artifacts. These artifacts cannot be accurately corrected...

To develop a radial, double-echo steady-state (DESS) sequence with ultra-short echo-time (UTE) capabilities for T2 measurement of short-T2 tissues along simultaneous rapid, signal-to-noise ratio (SNR)-efficient, and high-isotropic-resolution morphological knee imaging.THe 3D radial UTE readouts were incorporated into DESS, termed UTEDESS. Multiple-echo-time UTEDESS was used performing relaxometry tendons, ligaments, menisci; Dixon water-fat imaging. In vivo estimate repeatability SNR...

Purpose To assess the feasibility of ferumoxytol‐enhanced anesthesia‐free cardiac MRI in neonates and young infants for complex congenital heart disease (CHD). Materials Methods With Institutional Review Board approval, 21 consecutive (1 day to 11 weeks old; median age 3 days) who underwent a rapid two‐sequence (MR angiography [MRA] four‐dimensional [4D] flow) protocol with intravenous ferumoxytol without sedation (n = 17) or light 4) at Tesla (T) (except one case 1.5T) between June 2014...

Purpose To develop a robust motion estimation method for free‐breathing body MRI using dense coil arrays. Methods Self‐navigating pulse sequences can measure subject without external monitoring devices. With arrays, individual elements provide localized estimates. An averaged estimate over all coils is often used compensation. However, this may not accurately represent the dominant within imaging volume. In work, clustering proposed to automatically determine The feasibility of investigated...

Purpose To design, construct, and validate a semiflexible 64‐channel receive‐only phased array for pediatric body MRI at 3T. Methods A was developed constructed. The designed flexible coil can easily conform to different patient sizes with nonoverlapping elements in the transverse plane. It cover field of view up 44 × 28 cm 2 removes need repositioning patients multiple clinical concerns. compared 32‐channel standard signal‐to‐noise ratio parallel imaging performances on phantoms. With IRB...

Purpose To develop a fast and robust method to resolve phase ambiguity in dual‐echo Dixon imaging. Methods A major challenge imaging is estimate the error resulting from field inhomogeneity. In this work, binary quadratic optimization program was formulated ambiguity. projected power developed efficiently solve problem. Both 1‐peak fat model 6‐peak were applied three‐dimensional (3D) datasets. Additionally, proposed extended dynamic magnetic resonance (MRI) applications using model. With...

Q-spoiling is the process of decoupling an MRI receive coil to protect equipment and patient. Conventionally, performed using a PIN diode switch that draws significant current. In this work, technique depletion-mode Gallium Nitride HEMT device was developed for detuning at both 1.5 T 3 MRI. The circuits with conventional GaN were implemented on surface coils. SNR measured compared all surfaces At T, comparable achieved coils proposed Q-spoiling. has significantly reduced required power also...

Background It is highly desirable in clinical abdominal MR scans to accelerate single‐shot fast spin echo (SSFSE) imaging and reduce blurring due T 2 decay partial‐Fourier acquisition. Purpose To develop investigate the feasibility of wave‐encoded variable‐density SSFSE for improved image quality scan time reduction. Study Type Prospective controlled trial. Subjects With Institutional Review Board approval informed consent, proposed method was assessed on 20 consecutive adult patients (10...

Purpose To develop a motion‐robust wave‐encoding technique for highly accelerated free‐breathing abdominal MRI. Methods A comprehensive 3D wave‐encoding‐based method was developed to enable fast imaging: (a) auto‐calibration designed avoid extra scan coil sensitivity measurement; (b) intrinsic butterfly navigators were used track respiratory motion; (c) variable‐density sampling included compressed sensing; (d) golden‐angle radial‐Cartesian hybrid view‐ordering incorporated improve motion...

Several planning algorithms have been developed for topography-guided custom ablation treatment (T-CAT), but each has its own deficiencies. The purpose of this study is to demonstrate the potential a novel mutual comparative analysis (MCA) informed by manifest refraction and corneal topographic data patient's subjective perception in correcting ametropia. This retrospective review included patients with significant preoperative differences power or axis astigmatism according (power > 0.75 D...

Echo signals in different regions the k-space of magnetic resonance imaging (MRI) data possess amplitudes. The signal-to-noise ratio (SNR) a received signal can be improved by differentially setting receiving gain (RG) parameter areas k-space. Previously, splicing method and normalization implementation were not specifically investigated; however, this study focuses on aspect. Specifically, to improve SNR, three RGs MRI scans are herein designed for each using gradient echo sequence obtain...

Radiolabeled prostate-specific membrane antigen (PSMA) ligands have been rapidly adopted as part of patient care for prostate cancer. In this study, a new series 18F-labeled PSMA-targeting agents was developed based on the high-affinity Glu-ureido-Lys scaffold and 18F-vinyl sulfones (VSs), tumor uptake tumor/major organ contrast which could be tuned by pharmacokinetic linkers within molecules. particular, 18F-PEG3-VS-PSMAi showed highest (12.1 ± 2.2%ID/g at 0.5 h p.i.) 18F-PEG2-VS-PSMAi...