A Pharmacokinetics, Efficacy, and Safety Study of Gadoterate Meglumine in Pediatric Subjects Aged Younger Than 2 Years
Conclusions The pharmacokinetic profile of gadoterate meglumine after a single intravenous injection of 0.1 mmol/kg was appropriately described in newborns and infants younger than 2 years, for whom no dose adjustment is required. The improved efficacy of gadoterate meglumine for contrast-enhanced MRI examination of brain, spine, and associated tissues, as well as its good safety profile, was also demonstrated in this population. (Source: Investigative Radiology)
Source: Investigative Radiology - January 17, 2018 Category: Radiology Tags: Original Articles Source Type: research

Unenhanced Dual-Energy Computed Tomography: Visualization of Brain Edema
Purpose The aim of this study was to determine whether dual-energy computed tomography (DECT) imaging is superior to conventional noncontrast computed tomography (CT) imaging for the detection of acute ischemic stroke. Materials and Methods This was a retrospective, single-center study of 40 patients who presented to the emergency department (ED) of a major, acute care, teaching center with signs and symptoms of acute stroke. Only those patients who presented to the ED within 4 hours of symptom onset were included in this study. All 40 patients received a noncontrast DECT of the head at the time of presentation. Each ...
Source: Investigative Radiology - January 17, 2018 Category: Radiology Tags: Original Articles Source Type: research

Contrast Media Research 2017 Durango, Colorado USA, October 22–25, 2017 Convener: Michael F. Tweedle, PhD Erratum
No abstract available (Source: Investigative Radiology)
Source: Investigative Radiology - January 2, 2018 Category: Radiology Tags: Erratum Source Type: research

Comparison of Unenhanced T1-Weighted Signal Intensities Within the Dentate Nucleus and the Globus Pallidus After Serial Applications of Gadopentetate Dimeglumine Versus Gadobutrol in a Pediatric Population
Objective The aim of this study was to evaluate and compare changes in T1-weighted signal intensity (SI) within the dentate nucleus (DN) and globus pallidus (GP) in a pediatric population after serial applications of the linear gadolinium-based magnetic resonance contrast medium gadopentetate dimeglumine and the more stable macrocyclic agent gadobutrol. Materials and Methods Institutional review board approval was obtained. Two similar pediatric patient cohorts who underwent at least 3 serial contrast-enhanced magnetic resonance imaging (MRI) examinations with sole application of gadopentetate dimeglumine or gadobutro...
Source: Investigative Radiology - January 2, 2018 Category: Radiology Tags: Original Articles Source Type: research

The Effect of Perinatal Gadolinium-Based Contrast Agents on Adult Mice Behavior
Conclusions In the present study, we showed that Gd was transferred to pups and was retained in their brain during postnatal development. Gadolinium retention may lead to impaired brain development. These findings indicate that the use of GBCAs in pregnant women should be avoided because it may have adverse effects on the fetus, particularly on brain development. (Source: Investigative Radiology)
Source: Investigative Radiology - January 2, 2018 Category: Radiology Tags: Original Articles Source Type: research

Heavily Calcified Coronary Arteries: Advanced Calcium Subtraction Improves Luminal Visualization and Diagnostic Confidence in Dual-Energy Coronary Computed Tomography Angiography
Conclusions A prototype algorithm for calcium subtraction improves coronary lumen visualization and diagnostic confidence in patients with heavy coronary calcifications without differences in conventional subjective and objective measures of image quality. (Source: Investigative Radiology)
Source: Investigative Radiology - January 2, 2018 Category: Radiology Tags: Original Articles Source Type: research

Multiparametric Magnetic Resonance Imaging of Prostate Cancer Bone Disease: Correlation With Bone Biopsy Histological and Molecular Features
Objectives The aim of this study was to correlate magnetic resonance imaging (MRI) of castration-resistant prostate cancer (CRPC) bone metastases with histological and molecular features of bone metastases. Materials and Methods Forty-three bone marrow biopsies from 33 metastatic CRPC (mCRPC) patients with multiparametric MRI and documented bone metastases were evaluated. A second cohort included 10 CRPC patients with no bone metastases. Associations of apparent diffusion coefficient (ADC), normalized b900 diffusion-weighted imaging (nDWI) signal, and signal-weighted fat fraction (swFF) with bone marrow biopsy histolo...
Source: Investigative Radiology - January 2, 2018 Category: Radiology Tags: Original Articles Source Type: research

Quantitative Proton Spectroscopy of the Testes at 3 T: Toward a Noninvasive Biomarker of Spermatogenesis
Conclusions Testicular metabolite concentrations, measured by proton spectroscopy at 3 T, may be valuable as noninvasive biomarkers of spermatogenesis. (Source: Investigative Radiology)
Source: Investigative Radiology - January 2, 2018 Category: Radiology Tags: Original Articles Source Type: research

Non contrast, Pseudo-Continuous Arterial Spin Labeling and Accelerated 3-Dimensional Radial Acquisition Intracranial 3-Dimensional Magnetic Resonance Angiography for the Detection and Classification of Intracranial Arteriovenous Shunts
Conclusion Noncontrast PCASL-MRA with 3D radial acquisition is a potential tool for the detection and characterization of intracranial AV shunts with a sensitivity and specificity equivalent or higher than routine clinical MRA. (Source: Investigative Radiology)
Source: Investigative Radiology - January 2, 2018 Category: Radiology Tags: Original Articles Source Type: research

A Pharmacokinetics, Efficacy, and Safety Study of Gadoterate Meglumine in Pediatric Subjects Aged Younger Than 2 Years
Conclusions The pharmacokinetic profile of gadoterate meglumine after a single intravenous injection of 0.1 mmol/kg was appropriately described in newborns and infants younger than 2 years, for whom no dose adjustment is required. The improved efficacy of gadoterate meglumine for contrast-enhanced MRI examination of brain, spine, and associated tissues, as well as its good safety profile, was also demonstrated in this population. (Source: Investigative Radiology)
Source: Investigative Radiology - January 2, 2018 Category: Radiology Tags: Original Articles Source Type: research

Unenhanced Dual-Energy Computed Tomography: Visualization of Brain Edema
Purpose The aim of this study was to determine whether dual-energy computed tomography (DECT) imaging is superior to conventional noncontrast computed tomography (CT) imaging for the detection of acute ischemic stroke. Materials and Methods This was a retrospective, single-center study of 40 patients who presented to the emergency department (ED) of a major, acute care, teaching center with signs and symptoms of acute stroke. Only those patients who presented to the ED within 4 hours of symptom onset were included in this study. All 40 patients received a noncontrast DECT of the head at the time of presentation. Each ...
Source: Investigative Radiology - January 2, 2018 Category: Radiology Tags: Original Articles Source Type: research

Evaluation of Transient Motion During Gadoxetic Acid–Enhanced Multiphasic Liver Magnetic Resonance Imaging Using Free-Breathing Golden-Angle Radial Sparse Parallel Magnetic Resonance Imaging
Objectives The aims of this study were to observe the pattern of transient motion after gadoxetic acid administration including incidence, onset, and duration, and to evaluate the clinical feasibility of free-breathing gadoxetic acid–enhanced liver magnetic resonance imaging using golden-angle radial sparse parallel (GRASP) imaging with respiratory gating. Materials and Methods In this institutional review board–approved prospective study, 59 patients who provided informed consents were analyzed. Free-breathing dynamic T1-weighted images (T1WIs) were obtained using GRASP at 3 T after a standard dose of gad...
Source: Investigative Radiology - December 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Increased Expiratory Computed Tomography Density Reveals Possible Abnormalities in Radiologically Preserved Lung Parenchyma in Idiopathic Pulmonary Fibrosis
Conclusions High CT attenuation changes between inspiration and expiration in IPF patients might suggest altered lung parenchyma in normal-appearing tissue on CT. Density changes during the respiratory cycle might be explained by alveolar collapse of radiologically unaffected lung tissue possibly preceding fibrosis. These results support the concept of alveolar collapse preceding lung fibrosis in IPF. (Source: Investigative Radiology)
Source: Investigative Radiology - December 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Motion-Corrected Real-Time Cine Magnetic Resonance Imaging of the Heart: Initial Clinical Experience
Objectives Free-breathing real-time (RT) imaging can be used in patients with difficulty in breath-holding; however, RT cine imaging typically experiences poor image quality compared with segmented cine imaging because of low resolution. Here, we validate a novel unsupervised motion-corrected (MOCO) reconstruction technique for free-breathing RT cardiac images, called MOCO-RT. Motion-corrected RT uses elastic image registration to generate a single heartbeat of high-quality data from a free-breathing RT acquisition. Materials and Methods Segmented balanced steady-state free precession (bSSFP) cine images and free-brea...
Source: Investigative Radiology - December 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Qualitative and Quantitative Evaluation of Structural Myocardial Alterations by Grating-Based Phase-Contrast Computed Tomography
Objectives Grating-based phase-contrast computed tomography (gb-PCCT) relies on x-ray refraction instead of absorption to generate high-contrast images in biological soft tissue. The aim of this study was to evaluate the potential of gb-PCCT for the depiction of structural changes in heart disease. Materials and Methods Four human heart specimens from patients with hypertensive disease, ischemic disease, dilated heart disease, and cardiac lipomatosis were examined. The gb-PCCT setup consisted of an x-ray tube (40 kV, 70 mA), grating-interferometer, and detector, and allowed simultaneous acquisition of phase- and absor...
Source: Investigative Radiology - December 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Evaluation of Gadolinium Retention After Serial Administrations of a Macrocyclic Gadolinium-Based Contrast Agent (Gadobutrol): A Single-Institution Experience With 189 Patients
Conclusions Serial administrations of gadobutrol did not result in signal increases in the DN or GP on unenhanced T1-weighted MR images due to gadolinium retention. (Source: Investigative Radiology)
Source: Investigative Radiology - December 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Multiple Sclerosis: Improved Detection of Active Cerebral Lesions With 3-Dimensional T1 Black-Blood Magnetic Resonance Imaging Compared With Conventional 3-Dimensional T1 GRE Imaging
Objectives The aim of this study was to assess the diagnostic accuracy of a modified high-resolution whole-brain three-dimensional T1-weighted black-blood sequence (T1-weighted modified volumetric isotropic turbo spin echo acquisition [T1-mVISTA]) in comparison to a standard three-dimensional T1-weighted magnetization-prepared rapid gradient echo (MP-RAGE) sequence for detection of contrast-enhancing cerebral lesions in patients with relapsing-remitting multiple sclerosis (MS). Materials and Methods After institutional review board approval and informed consent, 22 patients (8 men; aged 31.0 ± 9.2 years) with r...
Source: Investigative Radiology - December 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Iterative Reconstruction May Improve Diagnosis of Gout: An Ex Vivo (Bio)Phantom Dual-Energy Computed Tomography Study
Conclusions Iterative reconstruction has the potential to improve the sensitivity of a DECT scan for gouty tophi, to decrease radiation exposure, or to combine both options. (Source: Investigative Radiology)
Source: Investigative Radiology - December 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Accuracy and Repeatability of Automated Injector Versus Manual Administration of an MRI Contrast Agent—Results of a Laboratory Study
Objective The aim of this study was to compare flow rates over time and the deviations from the target flow rate of a magnetic resonance imaging contrast agent achieved by an automated injector versus manual injection. Materials and Methods In this laboratory study, the magnetic resonance contrast agent gadobutrol was repeatedly injected by an injector and by 10 experienced technologists. Six scenarios with 2 different target flow rates (1 and 5 mL/s), 2 different contrast volumes (10 and 20 mL), and 2 different intravenous (IV) catheters (22 gauge and 20 gauge) were tested. The flow rates over time were recorded. The...
Source: Investigative Radiology - December 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Contrast Media Research 2017 Durango, Colorado USA, October 22–25, 2017 Convener: Michael F. Tweedle, PhD
No abstract available (Source: Investigative Radiology)
Source: Investigative Radiology - November 7, 2017 Category: Radiology Tags: Abstracts Source Type: research

Intravoxel Incoherent Motion: Model-Free Determination of Tissue Type in Abdominal Organs Using Machine Learning
Conclusions: Machine learning allows for a model-free determination of tissue type using intra voxel incoherent motion signal decay curves as features. The technique may be useful for segmentation of abdominal organs or distinction between healthy and pathological tissues. (Source: Investigative Radiology)
Source: Investigative Radiology - November 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Somatotopic Fascicular Lesions of the Brachial Plexus Demonstrated by High-Resolution Magnetic Resonance Neurography
Conclusions: Brachial plexus MRN is highly accurate for differentiating patients with symptomatic plexopathy from healthy controls and for distinguishing patients with compressive neuropathy and noncompressive plexopathy. Furthermore, BP MRN revealed evidence for somatotopic organization of the BP. Therefore, as an addition to functional information of electrodiagnostic studies, anatomical information gained by BP MRN may help to improve the efficiency and accuracy of patient care. (Source: Investigative Radiology)
Source: Investigative Radiology - November 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

The Diagnostic Value of 3-Dimensional Sampling Perfection With Application Optimized Contrasts Using Different Flip Angle Evolutions (SPACE) MRI in Evaluating Lower Extremity Deep Venous Thrombus
Conclusions: Non–contrast-enhanced 3-dimensional SPACE magnetic resonance imaging is highly accurate in detecting lower extremity DVT and reliable in the evaluation of clot burden. SPACE could serve as an important alternative for patients in whom US cannot be performed. (Source: Investigative Radiology)
Source: Investigative Radiology - November 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Magnetic Resonance Lymphography at 9.4 T Using a Gadolinium-Based Nanoparticle in Rats: Investigations in Healthy Animals and in a Hindlimb Lymphedema Model
Conclusions: This study demonstrates that AGuIX is a suitable contrast agent for preclinical interstitial MRL in rodents. AGuIX yields anatomical imaging of lymphatic vessels with diameters greater than 200 μm. Moreover, it resides in the lymphatic system for a prolonged time. AGuIX may therefore facilitate high-resolution MRL-based analyses of the lymphatic system in rodents. (Source: Investigative Radiology)
Source: Investigative Radiology - November 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Quantitative Perfusion Analysis of the Rectum Using Golden-Angle Radial Sparse Parallel Magnetic Resonance Imaging: Initial Experience and Comparison to Time-Resolved Angiography With Interleaved Stochastic Trajectories
Objectives: Purpose of this study was to compare the quality of perfusion maps obtained from prototypical free-breathing magnetic resonance imaging (MRI) with continuous golden-angle radial sampling and iterative reconstruction (GRASP) to conventional acquisition using time-resolved angiography with interleaved stochastic trajectories (TWIST) in patients with rectal cancer. Material and Methods: Forty cases were included for retrospective analysis. Twenty of the patients received routine multiparametric MRI at 3 T for rectal cancer staging, including perfusion measurement with GRASP or TWIST (10 patients for each techniqu...
Source: Investigative Radiology - November 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

The Fourth Edition of The Physics of Clinical MR Taught Through Images
No abstract available (Source: Investigative Radiology)
Source: Investigative Radiology - October 11, 2017 Category: Radiology Tags: Book Review Source Type: research

Dynamic Liver Magnetic Resonance Imaging in Free-Breathing: Feasibility of a Cartesian T1-Weighted Acquisition Technique With Compressed Sensing and Additional Self-Navigation Signal for Hard-Gated and Motion-Resolved Reconstruction
Objectives: The aim of this study was to assess the feasibility of a free-breathing dynamic liver imaging technique using a prototype Cartesian T1-weighted volumetric interpolated breathhold examination (VIBE) sequence with compressed sensing and simultaneous acquisition of a navigation signal for hard-gated and motion state–resolved reconstruction. Materials and Methods: A total of 43 consecutive oncologic patients (mean age, 66 ± 11 years; 44% female) underwent free-breathing dynamic liver imaging for the evaluation of liver metastases from colorectal cancer using a prototype Cartesian VIBE sequence (field ...
Source: Investigative Radiology - October 11, 2017 Category: Radiology Tags: Original Articles Source Type: research

Diffusion Tensor Imaging in Chronic Inflammatory Demyelinating Polyneuropathy: Diagnostic Accuracy and Correlation With Electrophysiology
Purpose: The aims of this study were to assess diagnostic accuracy of diffusion tensor imaging (DTI) in chronic inflammatory demyelinating polyneuropathy (CIDP), to correlate DTI with electrophysiological parameters, and to evaluate whether radial diffusivity (RD) and axial diffusivity (AD) might serve as specific biomarkers of demyelinating and axonal pathology. Materials and Methods: This prospective study was approved by the institutional ethics committee, and written informed consent was obtained from all participants. Magnetic resonance neurography of upper and lower extremity nerves (median, ulnar, radial, sciatic, ...
Source: Investigative Radiology - October 11, 2017 Category: Radiology Tags: Original Articles Source Type: research

Spatial Distribution of Iron Within the Normal Human Liver Using Dual-Source Dual-Energy CT Imaging
Conclusions: Dual-source dual-energy CT can be used to assess the uniformity of iron distribution in healthy subjects. Applying similar techniques to unhealthy livers, future research may focus on the impact of hepatic iron content and distribution for noninvasive assessment in diseased subjects. (Source: Investigative Radiology)
Source: Investigative Radiology - October 11, 2017 Category: Radiology Tags: Original Articles Source Type: research

Magnetization Transfer Magnetic Resonance Imaging Noninvasively Detects Renal Fibrosis in Swine Atherosclerotic Renal Artery Stenosis at 3.0 T
In this study, we aimed to identify appropriate imaging parameters for collagen detection at 3.0 T MRI and to test the utility of MT-MRI in measuring renal fibrosis in a swine model of atherosclerotic RAS (ARAS). Materials and Methods: To select the appropriate offset frequency, an MT-MRI study was performed on a phantom containing 0% to 40% collagen I and III with offset frequencies from −1600 to +1600 Hz and other MT parameters empirically set as pulse width at 16 milliseconds and flip angle at 800 degrees. Then selected MT parameters were used in vivo on pigs 12 weeks after sham (n = 8) or RAS (n = 10) surgeries....
Source: Investigative Radiology - October 11, 2017 Category: Radiology Tags: Original Articles Source Type: research

Modified Dual-Energy Algorithm for Calcified Plaque Removal: Evaluation in Carotid Computed Tomography Angiography and Comparison With Digital Subtraction Angiography
Objectives: Computed tomography angiography (CTA) is a valuable tool for the assessment of carotid artery stenosis. However, blooming artifacts from calcified plaques might result in an overestimation of the stenosis grade. The aim of this study was to investigate a new dual-energy computed tomography (DECT) technique with a modified 3-material decomposition algorithm for calcium removal in extracranial carotid artery stenosis. Materials and Methods: In this retrospective, institutional review board-approved study, 30 calcified carotid plaques in 22 patients (15 men; mean age, 73 ± 10 years) with clinical suspicion...
Source: Investigative Radiology - October 11, 2017 Category: Radiology Tags: Original Articles Source Type: research

Renal Adiposity Confounds Quantitative Assessment of Markers of Renal Diffusion With MRI: A Proposed Correction Method
Conclusions: Excessive renal fat may cause underestimation of renal ADC and IVIM-derived pure-diffusivity, which may hinder detection of renal pathology. Models accounting for fat contribution may help reduce the variability of diffusivity calculated using DWI. (Source: Investigative Radiology)
Source: Investigative Radiology - October 11, 2017 Category: Radiology Tags: Original Articles Source Type: research

Seven-Tesla MRI of Hippocampal Sclerosis: An In Vivo Feasibility Study With Histological Correlations
Discussion: High-resolution, ultra-high-field MRI is a promising tool for the detection of subtle changes in the hippocampus in patients with temporal lobe epilepsy. Large cohorts will be necessary to confirm the predictive value of 7 T MRI in the preoperative evaluation of TLE patients. (Source: Investigative Radiology)
Source: Investigative Radiology - October 11, 2017 Category: Radiology Tags: Original Articles Source Type: research

Virtual Monoenergetic Imaging and Iodine Perfusion Maps Improve Diagnostic Accuracy of Dual-Energy Computed Tomography Pulmonary Angiography With Suboptimal Contrast Attenuation
Objectives: The aim of this study was to investigate the impact of virtual monoenergetic imaging (VMI+) and dual-energy computed tomography perfusion maps (DECT-PMs) on reader confidence and diagnostic accuracy in dual-energy computed tomography pulmonary angiography (DE-CTPA) studies with suboptimal contrast attenuation, compared with standard linearly blended reconstruction series. Materials and Methods: Dual-energy computed tomography pulmonary angiography examinations with suboptimal contrast attenuation of 68 patients with suspected pulmonary embolism (PE) were included in this institutional review board–approv...
Source: Investigative Radiology - October 11, 2017 Category: Radiology Tags: Original Articles Source Type: research

SyMRI of the Brain: Rapid Quantification of Relaxation Rates and Proton Density, With Synthetic MRI, Automatic Brain Segmentation, and Myelin Measurement
Abstract: Conventional magnetic resonance images are usually evaluated using the image signal contrast between tissues and not based on their absolute signal intensities. Quantification of tissue parameters, such as relaxation rates and proton density, would provide an absolute scale; however, these methods have mainly been performed in a research setting. The development of rapid quantification, with scan times in the order of 6 minutes for full head coverage, has provided the prerequisites for clinical use. The aim of this review article was to introduce a specific quantification method and synthesis of contrast-weighted...
Source: Investigative Radiology - September 7, 2017 Category: Radiology Tags: Review Article Source Type: research

High-Quality 3-Dimensional 1H Magnetic Resonance Spectroscopic Imaging of the Prostate Without Endorectal Receive Coil Using A Semi-LASER Sequence
Objectives: Inclusion of 3-dimensional 1H magnetic resonance spectroscopic imaging (3D-1H-MRSI) in routine multiparametric MRI of the prostate requires good quality spectra and easy interpretable metabolite maps of the whole organ obtained without endorectal coil in clinically feasible acquisition times. We evaluated if a semi-LASER pulse sequence with gradient offset independent adiabaticity refocusing pulses (GOIA-sLASER) for volume selection can meet these requirements. Materials and Methods: Thirteen patients with suspicion of prostate cancer and 1 patient known to have prostate cancer were examined at 3 T with a mult...
Source: Investigative Radiology - September 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Mapping an Extended Neurochemical Profile at 3 and 7 T Using Accelerated High-Resolution Proton Magnetic Resonance Spectroscopic Imaging
Objectives: The aim of this study was to compare high-resolution free induction decay magnetic resonance spectroscopic imaging (FID-MRSI) at 3 T and 7 T in the brain of healthy subjects and to showcase the clinical potential of accelerated FID-MRSI at 7 T in 2 brain tumor cases. Materials and Methods: In this institutional review board–approved study, 10 healthy volunteers (8 men/2 women; age: 31 ± 6 years) were measured at 3 T and 7 T (Trio and 7T-Magnetom; Siemens Healthcare, Germany) and 2 patients (a 38-year-old man and a 37-year-old man), 1 with an anaplastic oligoastrocytoma (grade III) and 1 with a low...
Source: Investigative Radiology - September 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Interleaved Mapping of Temperature and Longitudinal Relaxation Rate to Monitor Drug Delivery During Magnetic Resonance–Guided High-Intensity Focused Ultrasound-Induced Hyperthermia
Conclusions: The new approach of interleaving different MR sequences was applied to simultaneously acquire R1 maps and PRFS thermometry scans during a feedback-controlled MR-HIFU–induced hyperthermia treatment. Interleaved acquisition did not compromise speed or accuracy of each scan. The ΔR1 acquired during treatment was used to visualize and quantify hyperthermia-triggered release of gadoteridol from TSLs and better reflected the intratumoral doxorubicin concentrations than the ΔR1 measured after cooldown of the tumor, exemplifying the benefit of interleaving R1 maps with temperature maps during drug de...
Source: Investigative Radiology - September 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Clinical Feasibility of 3-Dimensional Magnetic Resonance Cholangiopancreatography Using Compressed Sensing: Comparison of Image Quality and Diagnostic Performance
Objective: The aim of this study was to evaluate the clinical feasibility of fast 3-dimensional (3D) magnetic resonance cholangiopancreatography (MRCP) using compressed sensing (CS) in comparison with conventional navigator-triggered 3D-MRCP. Materials and Methods: This retrospective study was approved by our institutional review board, and the requirement of informed consent was waived. A total of 84 patients (male-to-female ratio, 41:43; mean age, 47.3 ± 18.8 years) who underwent conventional 3D navigator-triggered T2-weighted MRCP using sampling perfection with application optimized contrasts (SPACE) and fast 3D...
Source: Investigative Radiology - September 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Application of High-Speed T1 Sequences for High-Quality Hepatic Arterial Phase Magnetic Resonance Imaging: Intraindividual Comparison of Single and Multiple Arterial Phases
Purpose: The aim of this study was to compare intraindividual single and multiple arterial phase acquisitions and evaluate which acquisition method was more advantageous for obtaining high-quality hepatic arterial phase in gadoxetic acid–enhanced liver magnetic resonance imaging (MRI). Materials and Methods: Sixty-seven patients who underwent gadoxetic acid–enhanced liver MRIs and had all 3 kinds of acquisitions (single, dual, and triple arterial phases) were retrospectively included. For hepatic arterial phase imaging, controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA) with or...
Source: Investigative Radiology - September 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Clinical Feasibility of Free-Breathing Dynamic T1-Weighted Imaging With Gadoxetic Acid–Enhanced Liver Magnetic Resonance Imaging Using a Combination of Variable Density Sampling and Compressed Sensing
Objectives: The purpose of the study was to investigate the clinical feasibility of free-breathing dynamic T1-weighted imaging (T1WI) using Cartesian sampling, compressed sensing, and iterative reconstruction in gadoxetic acid–enhanced liver magnetic resonance imaging (MRI). Materials and Methods: This retrospective study was approved by our institutional review board, and the requirement for informed consent was waived. A total of 51 patients at high risk of breath-holding failure underwent dynamic T1WI in a free-breathing manner using volumetric interpolated breath-hold (BH) examination with compressed sensing rec...
Source: Investigative Radiology - September 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Clinical Robustness of Accelerated and Optimized Abdominal Diffusion-Weighted Imaging
Objectives: The aim of this study was to assess the robustness of an accelerated and optimized diffusion-weighted sequence in clinical routine abdominal imaging using the simultaneous multislice (SMS) technique for scan time reduction and 3-dimensional (3D) diagonal diffusion mode to optimize image quality. Materials and Methods: One hundred fifty consecutive patients received clinically indicated magnetic resonance imaging for abdominal imaging including an optimized SMS diffusion-weighted sequence (DWIOPT: diffusion mode 3D diagonal; SMS factor 2; scan time 1:44 minutes). A subgroup of 41 patients additionally received ...
Source: Investigative Radiology - September 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Comprehensive Dynamic Contrast-Enhanced 3D Magnetic Resonance Imaging of the Breast With Fat/Water Separation and High Spatiotemporal Resolution Using Radial Sampling, Compressed Sensing, and Parallel Imaging
Objectives: The aim of this study was to assess the applicability of Dixon radial volumetric encoding (Dixon-RAVE) for comprehensive dynamic contrast-enhanced 3D magnetic resonance imaging (MRI) of the breast using a combination of radial sampling, model-based fat/water separation, compressed sensing, and parallel imaging. Materials and Methods: In this Health Insurance Portability and Accountability Act–compliant prospective study, 24 consecutive patients underwent bilateral breast MRI, including both conventional fat-suppressed and non–fat-suppressed precontrast T1-weighted volumetric interpolated breath-hol...
Source: Investigative Radiology - September 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Compressed Sensing for Breast MRI: Resolving the Trade-Off Between Spatial and Temporal Resolution
Conclusions: Compressed-sensing volume-interpolated breath-hold examination allows an increase of the through-plane spatial resolution of ultrafast dynamic contrast-enhanced magnetic resonance imaging compared with TWIST at a comparable in-plane IQ. Morphological assessment of lesions using CS-VIBE is comparable to VIBE-DIXON, which takes 18 times longer. Consequently, CS-VIBE enables 3D evaluation of breast lesions in ultrafast breast MRI. (Source: Investigative Radiology)
Source: Investigative Radiology - September 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

T2-Weighted 4D Magnetic Resonance Imaging for Application in Magnetic Resonance–Guided Radiotherapy Treatment Planning
Conclusions: A methodology to obtain 4D-T2w MRI that retrospectively applies the motion information from 4D-T1w MRI to 3-dimensional T2w MRI was developed and verified. Four-dimensional T2w MRI can assist clinicians in delineating mobile lesions that are difficult to define on 4D-T1w MRI, because of poor tumor-tissue contrast. (Source: Investigative Radiology)
Source: Investigative Radiology - September 7, 2017 Category: Radiology Tags: Original Articles Source Type: research

Magnetic Resonance Imaging–Based Assessment of Breast Cancer–Related Lymphoedema Tissue Composition
This study also aims to compare affected and control (unaffected) arms of patients with diagnosed BCRL, providing an analysis of both the volume and the distribution of the different tissue components. Materials and Methods: The entire arm was imaged with a fluid-sensitive STIR and a 2-point 3-dimensional T1W gradient-echo–based Dixon sequences, acquired in sagittal orientation and covering the same imaging volume. An automated image postprocessing procedure was developed to simultaneously (1) contour the external volume of the arm and the muscle fascia, allowing separation of the epifacial and subfascial volumes; a...
Source: Investigative Radiology - August 12, 2017 Category: Radiology Tags: Original Articles Source Type: research

Comparison of Power Versus Manual Injection in Bolus Shape and Image Quality on Contrast-Enhanced Magnetic Resonance Angiography: An Experimental Study in a Swine Model
Objective: The aim of this study was to compare power versus manual injection in bolus shape and image quality on contrast-enhanced magnetic resonance angiography (CE-MRA). Materials and Methods: Three types of CE-MRA (head-neck 3-dimensional [3D] MRA with a test-bolus technique, thoracic-abdominal 3D MRA with a bolus-tracking technique, and thoracic-abdominal time-resolved 4-dimensional [4D] MRA) were performed after power and manual injection of gadobutrol (0.1 mmol/kg) at 2 mL/s in 12 pigs (6 sets of power and manual injections for each type of CE-MRA). For the quantitative analysis, the signal-to-noise ratio was measu...
Source: Investigative Radiology - August 12, 2017 Category: Radiology Tags: Original Articles Source Type: research

Multiparametric Magnetic Resonance Imaging of the Prostate: Repeatability of Volume and Apparent Diffusion Coefficient Quantification
Objectives: The aim of this study was to evaluate the repeatability of a region of interest (ROI) volume and mean apparent diffusion coefficient (ADC) in standard-of-care 3 T multiparametric magnetic resonance imaging (mpMRI) of the prostate obtained with the use of endorectal coil. Materials and Methods: This prospective study was Health Insurance Portability and Accountability Act compliant, with institutional review board approval and written informed consent. Men with confirmed or suspected treatment-naive prostate cancer scheduled for mpMRI were offered a repeat mpMRI within 2 weeks. Regions of interest corresponding...
Source: Investigative Radiology - August 12, 2017 Category: Radiology Tags: Original Articles Source Type: research

Simultaneous Multislice Accelerated Turbo Spin Echo Magnetic Resonance Imaging: Comparison and Combination With In-Plane Parallel Imaging Acceleration for High-Resolution Magnetic Resonance Imaging of the Knee
Conclusions: We demonstrate the signal preservation capabilities of SMS over PAT acceleration, which allow for similar SNR and CNR of 4-fold PAT2-SMS2 and 2-fold PAT2-SMS1 acceleration. Four-fold–accelerated TSE through the combination of PAT2 and SMS2 enables approximately 50% shorter acquisition times compared with regular PAT2 acceleration, similar quantitative and qualitative image quality, and holds promise for a meaningful increase of the efficiency of clinical 2-dimensional MRI of the knee. (Source: Investigative Radiology)
Source: Investigative Radiology - August 12, 2017 Category: Radiology Tags: Original Articles Source Type: research

Computed Tomography of the Head and Neck Region for Tumor Staging—Comparison of Dual-Source, Dual-Energy and Low-Kilovolt, Single-Energy Acquisitions
Conclusions: High overall image quality for tumor delineation in head and neck imaging were obtained with 40-keV VMI. However, 70-kV SE examinations are an alternative and modified projections aligned to the jaw are recommended in case of severe artifacts caused by dental hardware. (Source: Investigative Radiology)
Source: Investigative Radiology - August 12, 2017 Category: Radiology Tags: Original Articles Source Type: research