Steady-State Multifrequency Magnetic Resonance Elastography of the Thoracic and Abdominal Human Aorta—Validation and Reference Values
Objectives The aim of this study was to investigate the potential of stroboscopic-wavefield-sampling-based multifrequency magnetic resonance elastography (sMRE) for quantifying the stiffness of the human thoracic and abdominal aorta in vivo. Materials and Methods The sMRE of the thoracic and abdominal aorta was performed at 1.5 T field strength in 20 healthy volunteers aged 27 to 77 years (3 women; median age, 33 years; interquartile range [IQR], 16 years). Compound maps of shear wave speed (SWS) were reconstructed and evaluated during the diastolic phase in 3 anatomical regions: ascending thoracic aorta (AA), descend...
Source: Investigative Radiology - June 11, 2020 Category: Radiology Tags: Original Articles Source Type: research

Novel Magnetic Resonance Late Gadolinium Enhancement With Fixed Short Inversion Time in Ischemic Myocardial Scars
Conclusions Short LGE is a fast, single breath-hold 3D LGE sequence with no need for myocardial nulling due to fixed inversion time with improved scar visibility, especially in subendocardial infarcts. (Source: Investigative Radiology)
Source: Investigative Radiology - June 11, 2020 Category: Radiology Tags: Original Articles Source Type: research

Computer-Aided Diagnosis in Multiparametric Magnetic Resonance Imaging Screening of Women With Extremely Dense Breasts to Reduce False-Positive Diagnoses
Conclusions Dedicated multiparametric CAD of breast MRI for BI-RADS 3 and 4 lesions in screening of women with extremely dense breasts has the potential to reduce false-positive diagnoses and consequently to reduce the number of biopsies without missing cancers. (Source: Investigative Radiology)
Source: Investigative Radiology - June 11, 2020 Category: Radiology Tags: Original Articles Source Type: research

Assessment of Low-Grade Focal Cartilage Lesions in the Knee With Sodium MRI at 7 T: Reproducibility and Short-Term, 6-Month Follow-up Data
Conclusions In vivo 23Na-MRI is a robust and reproducible method that allows to differentiate between low-grade, focal cartilage lesions and normal-appearing articular cartilage, which supports the concept that compositional cartilage changes can be found early, before the development of advanced morphological changes visible at clinical 3-T MRI. (Source: Investigative Radiology)
Source: Investigative Radiology - June 11, 2020 Category: Radiology Tags: Original Articles Source Type: research

Subregion Radiomics Analysis to Display Necrosis After Hepatic Microwave Ablation—A Proof of Concept Study
Conclusions Subregion radiomics analysis may improve visualization of coagulation necrosis after hepatic MWA in an in vivo porcine model. (Source: Investigative Radiology)
Source: Investigative Radiology - June 11, 2020 Category: Radiology Tags: Original Articles Source Type: research

The Performance of Chest CT in Evaluating the Clinical Severity of COVID-19 Pneumonia: Identifying Critical Cases Based on CT Characteristics
Conclusions A rapid, accurate severity assessment of COVID-19 pneumonia based on chest CT would be feasible and could provide help for making management decisions, especially for the critical cases. (Source: Investigative Radiology)
Source: Investigative Radiology - June 11, 2020 Category: Radiology Tags: Original Articles Source Type: research

Establishing Reference Intervals for Gadolinium Concentrations in Blood, Plasma, and Urine in Individuals Not Previously Exposed to Gadolinium-Based Contrast Agents
Objectives Over the recent years, there have been increasing concerns that exposure to gadolinium-based contrast agents (GBCAs) may be associated with retention of Gd within the skin, bones, and solid organs in patients with normal renal function, although the clinical implications of this deposition remain to be established. There are no published data available to guide the development of reference intervals for Gd concentrations in biological samples from healthy people. The aims of this study were to (1) determine whether healthy individuals who have not received GBCAs have detectable concentrations of Gd in their bl...
Source: Investigative Radiology - June 11, 2020 Category: Radiology Tags: Original Articles Source Type: research

Needle Heating During Interventional Magnetic Resonance Imaging at 1.5- and 3.0-T Field Strengths
Conclusions Under the herein used experimental conditions, clinically used MR-conditional needles can heat to supraphysiologic temperatures during prolonged MRI at 1.5 and 3.0 T field strengths; however, the temperature rise can be balanced to physiological ranges with proper selection of needle length, needle orientation, and pulse sequence parameters. Caution must be exercised when using different MRI systems, as results may not directly translate. (Source: Investigative Radiology)
Source: Investigative Radiology - May 9, 2020 Category: Radiology Tags: Original Articles Source Type: research

Right-Angled Traction Bronchiectasis in Differentiating Idiopathic Pulmonary Fibrosis Without Honeycombing From Idiopathic Nonspecific Interstitial Pneumonia
Objectives The aim of this study was to conduct a radiopathologic evaluation of right-angled traction bronchiectasis to differentiate idiopathic pulmonary fibrosis (IPF) without honeycombing from idiopathic nonspecific interstitial pneumonia (NSIP). Materials and Methods The derivation cohort included 78 consecutive patients with idiopathic NSIP (n = 39) or IPF (n = 39) without honeycombing who underwent preoperative thin-section computed tomography scans at a single tertiary hospital. The validation cohort comprised 22 patients (14 IPF and 8 NSIP) from another institution. We assessed conventional computed tomography...
Source: Investigative Radiology - May 9, 2020 Category: Radiology Tags: Original Articles Source Type: research

No Changes in T1 Relaxometry After a Mean of 11 Administrations of Gadobutrol
Objectives Quantitative T1 relaxometry is the benchmark in imaging potential gadolinium deposition and known to be superior to semiquantitative signal intensity ratio analyses. However, T1 relaxometry studies are rare, commonly limited to a few target structures, and reported results are inconsistent. We systematically investigated quantitative T1 relaxation times (qT1) of a variety of brain nuclei after serial application of gadobutrol. Materials and Methods Retrospectively, qT1 measurements were performed in a patient cohort with a mean number of 11 gadobutrol applications (n = 46) and compared with a control group...
Source: Investigative Radiology - May 9, 2020 Category: Radiology Tags: Original Articles Source Type: research

Impact of Software Parameter Settings on Image Quality of Virtual Grid Processed Radiography Images: A Contrast-Detail Phantom Study
In this study, we compared image quality (IQ) with a contrast-detail phantom (CDRAD 2.0; Artinis Medical Systems, Zetten, the Netherlands) of digital radiographs acquired without any grid (gridless) with those corrected for scatter by either software (SW)-based scatter correction (Virtual Grid) or a physical grid (grid). Furthermore, we determined the optimal Virtual Grid settings that lead to the best contrast-detail IQ score (inverse IQ figure). Materials and Methods Images were obtained with a cassette spot film device with an inserted portable flat-panel detector (Fujifilm, Tokyo, Japan). The CDRAD phantom was sandw...
Source: Investigative Radiology - May 9, 2020 Category: Radiology Tags: Original Articles Source Type: research

Signal Enhancement and Enhancement Kinetics of Gadobutrol, Gadoteridol, and Gadoterate Meglumine in Various Body Regions: A Comparative Animal Study
Objectives The signal enhancement (SE) and enhancement kinetics of gadolinium-based contrast agents (GBCAs) in T1-weighted magnetic resonance (MR) images depend on the relaxivity of the GBCA and its pharmacokinetic profile. This in vivo study systematically compared the SE (technical efficacy) and the enhancement kinetics of the 3 macrocyclic GBCAs gadobutrol, gadoteridol, and gadoterate meglumine in various body regions. Materials and Methods A total of 15 healthy male white New Zealand rabbits were randomly divided into 3 groups (n = 5/group). The GBCAs were injected intravenously (0.1 mmol/kg body weight) and signa...
Source: Investigative Radiology - May 9, 2020 Category: Radiology Tags: Original Articles Source Type: research

Fully Automated Segmentation of Connective Tissue Compartments for CT-Based Body Composition Analysis: A Deep Learning Approach
Conclusions Fully automated determination of body composition based on CT can be performed with excellent results using the open-source CNN DeepMedic. The trained model is made usable for research by a deployable and sharable application. (Source: Investigative Radiology)
Source: Investigative Radiology - May 9, 2020 Category: Radiology Tags: Original Articles Source Type: research

Quantitative Knee Arthrography in a Large Animal Model of Osteoarthritis Using Photon-Counting Detector CT
Objective The aim of this study was to grade cartilage damage in a swine model of osteoarthritis using a whole-body photon-counting detector (PCD) CT. Materials and Methods A multienergy phantom containing gadolinium (Gd) (2, 4, 8, and 16 mg/mL) and hydroxyapatite (200 and 400 mg/cc) was scanned using a PCD-CT system (48 × 0.25 mm collimation, 80 kV, 800 mAs, D50 reconstruction kernel) to serve as calibration for material decomposition and to assess quantification accuracy. Osteoarthritis was induced in Yucatan miniswine (n = 8) using 1.2 mg monoiodoacetate (MIA) injected into a randomized knee, whereas the cont...
Source: Investigative Radiology - May 9, 2020 Category: Radiology Tags: Original Articles Source Type: research

Double Low-Dose Dual-Energy Liver CT in Patients at High-Risk of HCC: A Prospective, Randomized, Single-Center Study
Objectives The aim of this study was to investigate the clinical feasibility of the simultaneous reduction of radiation and contrast doses using spectral computed tomography (CT) in patients at high-risk for hepatocellular carcinoma. Materials and Methods Between May 2017 and March 2018, this prospective study recruited participants at risk of hepatocellular carcinoma with body mass indexes less than 30 and randomly assigned them to either the standard-dose group or the double low-dose group, which targeted 30% reductions in both radiation and contrast media (NCT03045445). Lesion conspicuity as a primary endpoint and ...
Source: Investigative Radiology - May 9, 2020 Category: Radiology Tags: Original Articles Source Type: research

Clinical and High-Resolution CT Features of the COVID-19 Infection: Comparison of the Initial and Follow-up Changes
Objectives In late December 2019, an outbreak of coronavirus disease (COVID-19) in Wuhan, China was caused by a novel coronavirus, newly named severe acute respiratory syndrome coronavirus 2. We aimed to quantify the severity of COVID-19 infection on high-resolution chest computed tomography (CT) and to determine its relationship with clinical parameters. Materials and Methods From January 11, 2020, to February 5, 2020, the clinical, laboratory, and high-resolution CT features of 42 patients (26–75 years, 25 males) with COVID-19 were analyzed. The initial and follow-up CT, obtained a mean of 4.5 days and 11.6 da...
Source: Investigative Radiology - May 9, 2020 Category: Radiology Tags: Original Articles Source Type: research

The Clinical and Chest CT Features Associated With Severe and Critical COVID-19 Pneumonia
Objective The aim of this study was to investigate the clinical and computed tomography (CT) features associated with severe and critical coronavirus disease 2019 (COVID-19) pneumonia. Materials and Methods Eighty-three patients with COVID-19 pneumonia including 25 severe/critical cases and 58 ordinary cases were enrolled. The chest CT images and clinical data of them were reviewed and compared. The risk factors associated with disease severity were analyzed. Results Compared with the ordinary patients, the severe/critical patients had older ages, higher incidence of comorbidities, cough, expectoration, chest pain,...
Source: Investigative Radiology - May 9, 2020 Category: Radiology Tags: Original Articles Source Type: research

Image Domain Transfer by Deep Learning is Feasible in Multiple Sclerosis Clinical Practice
No abstract available (Source: Investigative Radiology)
Source: Investigative Radiology - April 8, 2020 Category: Radiology Tags: Editorial Source Type: research

Deep-Learning Generated Synthetic Double Inversion Recovery Images Improve Multiple Sclerosis Lesion Detection
Objectives The aim of the study was to implement a deep-learning tool to produce synthetic double inversion recovery (synthDIR) images and compare their diagnostic performance to conventional sequences in patients with multiple sclerosis (MS). Materials and Methods For this retrospective analysis, 100 MS patients (65 female, 37 [22–68] years) were randomly selected from a prospective observational cohort between 2014 and 2016. In a subset of 50 patients, an artificial neural network (DiamondGAN) was trained to generate a synthetic DIR (synthDIR) from standard acquisitions (T1, T2, and fluid-attenuated inversion ...
Source: Investigative Radiology - April 8, 2020 Category: Radiology Tags: Original Articles Source Type: research

Temperature-Sensitive Frozen-Tissue Imaging for Cryoablation Monitoring Using STIR-UTE MRI
Purpose The aim of this study was to develop a method to delineate the lethally frozen-tissue region (temperature less than −40°C) arising from interventional cryoablation procedures using a short tau inversion-recovery ultrashort echo-time (STIR-UTE) magnetic resonance (MR) imaging sequence. This method could serve as an intraprocedural validation of the completion of tumor ablation, reducing the number of local recurrences after cryoablation procedures. Materials and Methods The method relies on the short T1 and T2* relaxation times of frozen soft tissue. Pointwise Encoding Time with Radial Acquisition, a ...
Source: Investigative Radiology - April 8, 2020 Category: Radiology Tags: Original Articles Source Type: research

HLA-DRB1*15: 02 Is Associated With Iodinated Contrast Media–Related Anaphylaxis
Background The incidence of severe reaction induced by iodinated contrast media (ICM) has increased over the years with an increasing use of imaging modalities. Although ICM anaphylaxis is rare, it can be life-threatening, but currently, there is no biomarker that can identify individuals at risk of ICM anaphylaxis. Objective The aim of this study is to investigate the genetic susceptibility of ICM anaphylaxis. Methods Patients who had ICM anaphylaxis were enrolled in the study, and their blood samples were collected for genotyping of human leukocyte antigen (HLA)-A, -B, -C, and -DR. The results were compared with ...
Source: Investigative Radiology - April 8, 2020 Category: Radiology Tags: Original Articles Source Type: research

Ultrafast Intracranial Vessel Imaging With Non-Cartesian Spiral 3-Dimensional Time-of-Flight Magnetic Resonance Angiography at 1.5 T: An In Vitro and Clinical Study in Healthy Volunteers
Conclusions Spiral-TOFs may deliver high-quality intracranial vessel imaging thus matching the performance of conventional parallel imaging–accelerated TOFs (such as the SENSE). Specifically, imaging can be performed at unprecedented scan times as short as 1:32 minutes per sequence (70.12% scan time reduction compared with SENSE). Optionally, spiral imaging may also be used to increase spatial resolution while maintaining the scan time of a Cartesian-based acquisition schema. The CNR was decreased in spiral-TOF images. (Source: Investigative Radiology)
Source: Investigative Radiology - April 8, 2020 Category: Radiology Tags: Original Articles Source Type: research

Advanced Diffusion-Weighted Abdominal Imaging: Qualitative and Quantitative Comparison of High and Ultra-High: b: -Values for Lesion Detection and Image Quality
Introduction Magnetic resonance imaging (MRI) of the abdomen increasingly incorporates diffusion-weighted imaging (DWI) sequences. Whereas DWI can substantially aid in detecting and characterizing suspicious findings, it remains unclear to what extent the use of ultra-high b-value DWI might further be of aid for the radiologist especially when using DWI sequences with advanced processing. The target of this study was therefore to compare high and ultra-high b-value DWI in abdominal MRI examinations. Methods This institutional review board–approved, prospective study included abdominal MRI examinations of 70 onco...
Source: Investigative Radiology - April 8, 2020 Category: Radiology Tags: Original Articles Source Type: research

Performance of an Automated Workflow for Magnetic Resonance Imaging of the Prostate: Comparison With a Manual Workflow
Objectives The aim of this study was to evaluate the performance of an automated workflow for multiparametric magnetic resonance imaging (mpMRI) of the prostate compared with a manual mpMRI workflow. Materials and Methods This retrospective study was approved by the local ethics committee. Two MR technicians scanned 2 healthy volunteers with a prototypical highly automated workflow (Siemens Healthineers GmbH, Erlangen, Germany) and with a manually adjusted scan protocol each. Thirty patients (mean age ± standard deviation, 68 ± 11 years; range, 41–93 years) with suspected prostate cancer underwent ...
Source: Investigative Radiology - April 8, 2020 Category: Radiology Tags: Original Articles Source Type: research

Ultrasound Time-Harmonic Elastography of the Pancreas: Reference Values and Clinical Feasibility
Objectives Pancreatic ductal adenocarcinoma (PDAC) is a very aggressive tumor with a very low 5-year survival rate of 8%. The aims of this study are to determine reference values and physiologic confounders in healthy pancreas and to assess the diagnostic accuracy of ultrasound time-harmonic elastography (THE) in the detection of PDAC. Materials and Methods From March 2017 through May 2019, a total of 54 study participants with healthy pancreas (n = 33, CTR) or PDAC (n = 21) were prospectively enrolled. Repeatability of THE was tested in a CTR subgroup (n = 5) undergoing repeat measurement on 4 different days. Interob...
Source: Investigative Radiology - April 8, 2020 Category: Radiology Tags: Original Articles Source Type: research

Clinical Feasibility of Abbreviated Magnetic Resonance With Breath-Hold 3-Dimensional Magnetic Resonance Cholangiopancreatography for Surveillance of Pancreatic Intraductal Papillary Mucinous Neoplasm
Objectives To determine the clinical feasibility of abbreviated magnetic resonance image (MRI) using breath-hold 3-dimensional magnetic resonance cholangiopancreatography (3D-MRCP) (aMRI-BH) for pancreatic intraductal papillary mucinous neoplasm (IPMN) surveillance. Materials and Methods In this retrospective study, 123 patients with 158 pancreatic IPMNs (pathologically proven [n = 73] and typical image feature with ≥2-year stability [n = 85]) who underwent conventional MRI (cMRI) consisting of contrast-enhanced pancreatobiliary MRI with conventional and BH-3D-MRCP were included. Two readers independently evaluated...
Source: Investigative Radiology - April 8, 2020 Category: Radiology Tags: Original Articles Source Type: research

Chest CT Findings in Patients With Coronavirus Disease 2019 and Its Relationship With Clinical Features
Objectives The aim of this study was to investigate the chest computed tomography (CT) findings in patients with confirmed coronavirus disease 2019 (COVID-19) and to evaluate its relationship with clinical features. Materials and Methods Study sample consisted of 80 patients diagnosed as COVID-19 from January to February 2020. The chest CT images and clinical data were reviewed, and the relationship between them was analyzed. Results Totally, 80 patients diagnosed with COVID-19 were included. With regards to the clinical manifestations, 58 (73%) of the 80 patients had cough, and 61 (76%) of the 80 patients had high...
Source: Investigative Radiology - April 8, 2020 Category: Radiology Tags: Original Articles Source Type: research

Deep Learning Approach for Generating MRA Images From 3D Quantitative Synthetic MRI Without Additional Scans
Objectives Quantitative synthetic magnetic resonance imaging (MRI) enables synthesis of various contrast-weighted images as well as simultaneous quantification of T1 and T2 relaxation times and proton density. However, to date, it has been challenging to generate magnetic resonance angiography (MRA) images with synthetic MRI. The purpose of this study was to develop a deep learning algorithm to generate MRA images based on 3D synthetic MRI raw data. Materials and Methods Eleven healthy volunteers and 4 patients with intracranial aneurysms were included in this study. All participants underwent a time-of-flight (TOF) M...
Source: Investigative Radiology - March 12, 2020 Category: Radiology Tags: Technical Notes Source Type: research

Clinical High-Resolution 3D-MR Spectroscopic Imaging of the Human Brain at 7 T
Objectives Available clinical magnetic resonance spectroscopic imaging (MRSI) sequences are hampered by long scan times, low spatial resolution, strong field inhomogeneities, limited volume coverage, and low signal-to-noise ratio. High-resolution, whole-brain mapping of more metabolites than just N-acetylaspartate, choline, and creatine within clinically attractive scan times is urgently needed for clinical applications. The aim is therefore to develop a free induction decay (FID) MRSI sequence with rapid concentric ring trajectory (CRT) encoding for 7 T and demonstrate its clinical feasibility for mapping the whole cere...
Source: Investigative Radiology - March 12, 2020 Category: Radiology Tags: Technical Notes Source Type: research

Simultaneous Multislice Diffusion-Weighted Imaging of the Kidneys at 3 T
Purpose The aim of this study was to compare respiratory-triggered diffusion-weighted imaging with simultaneous-multislice acceleration (SMS-RT-DWI) to a standard free-breathing echoplanar DWI (s-DWI) for 3 T renal imaging with respect to image quality and artifacts. Materials and Methods A total of 40 patients who had undergone renal magnetic resonance imaging were included in this retrospective analysis of a prospectively planned cohort study. All examinations were performed on a 3 T whole-body magnetic resonance system. Both s-DWI and SMS-RT-DWI were obtained and images were independently reviewed by 2 radiologists...
Source: Investigative Radiology - March 12, 2020 Category: Radiology Tags: Original Articles Source Type: research

A Universal Protocol for Abdominal CT Examinations Performed on a Photon-Counting Detector CT System: A Feasibility Study
Objective The aims of this study were to investigate the feasibility of using a universal abdominal acquisition protocol on a photon-counting detector computed tomography (PCD-CT) system and to compare its performance to that of single-energy (SE) and dual-energy (DE) CT using energy-integrating detectors (EIDs). Methods Iodine inserts of various concentrations and sizes were embedded into different sizes of adult abdominal phantoms. Phantoms were scanned on a research PCD-CT and a clinical EID-CT with SE and DE modes. Virtual monoenergetic images (VMIs) were generated from PCD-CT and DE mode of EID-CT. For each image...
Source: Investigative Radiology - March 12, 2020 Category: Radiology Tags: Original Articles Source Type: research

Magnetic Resonance Kidney Parenchyma-T2 as a Novel Imaging Biomarker for Autosomal Dominant Polycystic Kidney Disease
Objective Autosomal dominant polycystic kidney disease (ADPKD) is a chronic progressive disorder with a significant disease burden leading to end-stage renal disease in more than 75% of the affected individuals. Although prediction of disease progression is highly important, all currently available biomarkers—including height-adjusted total kidney volume (htTKV)—have important drawbacks in the everyday clinical setting. Thus, the purpose of this study was to evaluate T2 mapping as a source of easily obtainable and accurate biomarkers, which are needed for improved patient counseling and selection of targeted ...
Source: Investigative Radiology - March 12, 2020 Category: Radiology Tags: Original Articles Source Type: research

Molecular Magnetic Resonance Imaging of Fibrin Deposition in the Liver as an Indicator of Tissue Injury and Inflammation
Rationale and Objectives Liver inflammation is associated with nonalcoholic steatohepatitis and other pathologies, but noninvasive methods to assess liver inflammation are limited. Inflammation causes endothelial disruption and leakage of plasma proteins into the interstitial space and can result in extravascular coagulation with fibrin deposition. Here we assess the feasibility of using the established fibrin-specific magnetic resonance probe EP-2104R for the noninvasive imaging of fibrin as a marker of liver inflammation. Methods Weekly 100 mg/kg diethylnitrosamine (DEN) dosing was used to generate liver fibrosis in...
Source: Investigative Radiology - March 12, 2020 Category: Radiology Tags: Original Articles Source Type: research

Identification of Normal Pressure Hydrocephalus by Disease-Specific Patterns of Brain Stiffness and Damping Ratio
Objectives The aim of this study was to perform a whole-brain analysis of alterations in brain mechanical properties due to normal pressure hydrocephalus (NPH). Materials and Methods Magnetic resonance elastography (MRE) examinations were performed on 85 participants, including 44 cognitively unimpaired controls, 33 with NPH, and 8 who were amyloid-positive with Alzheimer clinical syndrome. A custom neural network inversion was used to estimate stiffness and damping ratio from patches of displacement data, accounting for edges by training the network to estimate the mechanical properties in the presence of missing dat...
Source: Investigative Radiology - March 12, 2020 Category: Radiology Tags: Original Article Source Type: research

Repeatability and Agreement of Shear Wave Speed Measurements in Phantoms and Human Livers Across 6 Ultrasound 2-Dimensional Shear Wave Elastography Systems
Conclusions There is good to excellent intersystem agreement of measured SWS in elastic phantoms and in vivo livers across 6 ultrasound 2D SWE systems. Test-retest repeatability was excellent for all systems. (Source: Investigative Radiology)
Source: Investigative Radiology - March 12, 2020 Category: Radiology Tags: Original Articles Source Type: research

Ultrafast Brain Magnetic Resonance Imaging in Acute Neurological Emergencies: Diagnostic Accuracy and Impact on Patient Management
Conclusions Ultrafast-MRI enables time-optimized diagnostic workup in acute neurological emergencies at high sensitivity and specificity compared with a standard-length protocol, with direct impact on patient management. Ultrafast MRI protocols are a powerful tool in the emergency setting and may be implemented on various scanner types based on the optimization of individual acquisition parameters. (Source: Investigative Radiology)
Source: Investigative Radiology - February 11, 2020 Category: Radiology Tags: Original Articles Source Type: research

Quantification of Aortic Stiffness by Ultrasound Time-Harmonic Elastography: The Effect of Intravascular Pressure on Elasticity Measures in a Porcine Model
Conclusions In our model, aortic stiffness measurements by ultrasound time-harmonic elastography are influenced to a small extent by mean arterial pressure in a range of 1.89% to 8.60%. These findings emphasize the potential of ultrasound THE for measuring the intrinsic stiffness of the aortic wall in clinical routine. (Source: Investigative Radiology)
Source: Investigative Radiology - February 11, 2020 Category: Radiology Tags: Original Articles Source Type: research

Dual Plasma Sampling Method to Determine the Hepatic and Renal Clearance of the 2 Diastereoisomers of Gd-EOB-DTPA
Objectives The aim of this study was to develop a method to determine hepatic and renal clearance of the 2 diastereoisomers (Gd-A, Gd-B) of Gd-EOB-DTPA separately. Materials and Methods Between July 2017 and February 2018, 41 patients with hepatic disease were prospectively included. For each patient, 1 mL of iopromide (to determine glomerular filtration rate [GFR]) was coadministered with Gd-EOB-DTPA (Gd-A and Gd-B; 65:35 wt/wt). The plasma clearances of Gd-A (PCL-GdA) and Gd-B (PCL-GdB) as well as the iopromide (GFR) were generated by using dual plasma sampling method. Meanwhile, the patient's urine was collected fo...
Source: Investigative Radiology - February 11, 2020 Category: Radiology Tags: Original Articles Source Type: research

Medication-Related Osteonecrosis of the Jaw—Comparison of Bone Imaging Using Ultrashort Echo-Time Magnetic Resonance Imaging and Cone-Beam Computed Tomography
Objective The aim of this study was to compare bone imaging between ultrashort echo-time (UTE) magnetic resonance (MR) imaging and cone-beam computed tomography (CBCT) as the reference standard in patients with medication-related osteonecrosis of the jaw (MRONJ). Materials and Methods A 1-year retrospective, blinded, and randomized qualitative analysis of UTE MR images and CBCT from 19 patients with clinically diagnosed MRONJ was performed by 2 independent radiologists. Medication-related osteonecrosis of the jaw imaging hallmarks such as osteolysis, periosteal thickening, and medullary osteosclerosis were rated visua...
Source: Investigative Radiology - February 11, 2020 Category: Radiology Tags: Original Articles Source Type: research

Respiratory Motion Detection and Correction for MR Using the Pilot Tone: Applications for MR and Simultaneous PET/MR Examinations
Conclusions The presented method provides reliable respiratory motion tracking during arbitrary imaging sequences throughout a full PET/MR study. All results can directly be transferred to MR-only applications as well. (Source: Investigative Radiology)
Source: Investigative Radiology - February 11, 2020 Category: Radiology Tags: Original Articles Source Type: research

Safety Analysis of Iobitridol as a Nonionic Contrast Medium: A Postmarketing Multicenter Surveillance Study With 94,960 Patients Almost 20 Years After Introduction
Objectives Our study sought to reevaluate the safety and diagnostic efficacy of iobitridol as a nonionic contrast medium after almost 20 years of use. Materials and methods This noninterventional postmarketing surveillance noncontrolled, multicenter (168 centers in Germany) study enrolled 94,960 patients receiving intravenous or intra-arterial iobitridol. The majority of the adjusted population (n = 92,550, 98.2%) underwent either computed tomography examination (n = 46,502, 49.3%) or intravenous urography (n = 46,048, 48.8%). A standardized questionnaire was used to ascertain patient's information, known risk factors...
Source: Investigative Radiology - February 11, 2020 Category: Radiology Tags: Original Articles Source Type: research

Long-Term Evaluation of Gadolinium Retention in Rat Brain After Single Injection of a Clinically Relevant Dose of Gadolinium-Based Contrast Agents
Purpose The aim of this study was to investigate the presence and chemical forms of residual gadolinium (Gd) in rat brain after a single dose of Gd-based contrast agent. Methods Four groups of healthy rats (2 sacrifice time-points, n = 10/group, 80 rats in total) were randomized to receive a single intravenous injection of 1 of the 3 Gd-based contrast agents (GBCAs) (gadoterate meglumine, gadobenate dimeglumine, or gadodiamide) or the same volume of 0.9% saline solution. The injected concentration was 0.6 mmol/kg, corresponding to a concentration of 0.1 mmol/kg in humans after body surface normalization between rats a...
Source: Investigative Radiology - February 11, 2020 Category: Radiology Tags: Original Articles Source Type: research

Dose Finding Study of Gadopiclenol, a New Macrocyclic Contrast Agent, in MRI of Central Nervous System
Conclusions Between the doses of 0.025 and 0.2 mmol/kg of gadopiclenol, the increase in CNR is linear. Compared with gadobenate dimeglumine at 0.1 mmol/kg, the doses of 0.05 and 0.1 mmol/kg of gadopiclenol gave similar or significantly greater contrast enhancement, respectively, and thus both doses can be considered for future phase III studies. (Source: Investigative Radiology)
Source: Investigative Radiology - February 11, 2020 Category: Radiology Tags: Original Articles Source Type: research

Effect of Long-Term Retention of Gadolinium on Metabolism of Deep Cerebellar Nuclei After Repeated Injections of Gadodiamide in Rats
Conclusions Repeated administration of gadodiamide lead to a retention of gadolinium preferentially within DCN at 1 year postinjections. This retention did not lead to any detectable changes of the measured metabolic biomarkers nor histological alterations. (Source: Investigative Radiology)
Source: Investigative Radiology - January 8, 2020 Category: Radiology Tags: Original Articles Source Type: research

Effects of Detector Sampling on Noise Reduction in Clinical Photon-Counting Whole-Body Computed Tomography
Conclusions Reconstruction of UHR data with a modulation transfer function below the system's resolution limit reduces image noise for all patient sizes and tube voltages compared with standard acquisitions. Thus, a relevant dose reduction may be clinically possible while maintaining image quality. (Source: Investigative Radiology)
Source: Investigative Radiology - January 8, 2020 Category: Radiology Tags: Original Articles Source Type: research

Using a Dual-Input Convolutional Neural Network for Automated Detection of Pediatric Supracondylar Fracture on Conventional Radiography
This study aimed to develop a dual-input convolutional neural network (CNN)–based deep-learning algorithm that utilizes both anteroposterior (AP) and lateral elbow radiographs for the automated detection of pediatric supracondylar fracture in conventional radiography, and assess its feasibility and diagnostic performance. Materials and Methods To develop the deep-learning model, 1266 pairs of AP and lateral elbow radiographs examined between January 2013 and December 2017 at a single institution were split into a training set (1012 pairs, 79.9%) and a validation set (254 pairs, 20.1%). We performed external tests ...
Source: Investigative Radiology - January 8, 2020 Category: Radiology Tags: Original Articles Source Type: research

Dose Reduction for Sinus and Temporal Bone Imaging Using Photon-Counting Detector CT With an Additional Tin Filter
Conclusions Phantom and cadaver studies demonstrated dose reduction using Sn-100 kV PCD-CT compared with current clinical EID-CT while maintaining the desired image contrast. Dose reduction was further validated in sinus and temporal bone patient studies. The ultra-high resolution capability from PCD-CT allowed improved anatomical delineation for sinus imaging compared with current clinical standard. (Source: Investigative Radiology)
Source: Investigative Radiology - January 8, 2020 Category: Radiology Tags: Original Articles Source Type: research

Improved Detection of Benign and Malignant Rib Lesions in the Routine Computed Tomography Workup of Oncological Patients Using Automated Unfolded Rib Image Postprocessing
Objective The aim of this study was to evaluate the performance of the automated computed tomography (CT) postprocessing software unfolded rib images for improved detection of both benign and malignant rib lesions during routine diagnostic workup of oncological patients. Materials and Methods One thousand eight in-patients and out-patients (63.66 ± 14.25 years; range, 18.67–95.67 years; 405 females and 603 males), undergoing chest CT between July 2018 to January 2019 at our institution, were retrospectively evaluated. Patients underwent chest CT alone or as part of a whole-body CT staging/restaging. The C...
Source: Investigative Radiology - January 8, 2020 Category: Radiology Tags: Special Issue on Advances in CT - Part II Source Type: research

Development of Upright Computed Tomography With Area Detector for Whole-Body Scans: Phantom Study, Efficacy on Workflow, Effect of Gravity on Human Body, and Potential Clinical Impact
Objectives Multiple human systems are greatly affected by gravity, and many disease symptoms are altered by posture. However, the overall anatomical structure and pathophysiology of the human body while standing has not been thoroughly analyzed due to the limitations of various upright imaging modalities, such as low spatial resolution, low contrast resolution, limited scan range, or long examination time. Recently, we developed an upright computed tomography (CT), which enables whole-torso cross-sectional scanning with 3-dimensional acquisition within 15 seconds. The purpose of this study was to evaluate the performance...
Source: Investigative Radiology - January 8, 2020 Category: Radiology Tags: Special Issue on Advances in CT - Part II Source Type: research

Dedicated Spiral Breast Computed Tomography With a Single Photon-Counting Detector: Initial Results of the First 300 Women
Conclusions The dedicated B-CT provides high-quality images. It can be used as alternative particularly in those patients not otherwise willing to perform mammography because of the breast compression. (Source: Investigative Radiology)
Source: Investigative Radiology - January 8, 2020 Category: Radiology Tags: Special Issue on Advances in CT - Part II Source Type: research