Comparison of T2 Quantification Strategies in the Abdominal-Pelvic Region for Clinical Use
Conclusions To perform T2 measurement in the abdominal-pelvic region, one should favor a technique with acceptable acquisition time for clinical use, with proper respiratory motion management, with good repeatability, reproducibility, and precision. In this study, the techniques relying respectively on SE-EPI, radial TSE, and GRAPPATINI appeared as good candidates. (Source: Investigative Radiology)
Source: Investigative Radiology - May 8, 2022 Category: Radiology Tags: Original Articles Source Type: research

Extracellular Volume Quantification With Cardiac Late Enhancement Scanning Using Dual-Source Photon-Counting Detector CT
Objectives The aim of this study was to evaluate the feasibility and accuracy of cardiac late enhancement (LE) scanning for extracellular volume (ECV) quantification with dual-source photon-counting detector computed tomography (PCD-CT). Materials and Methods In this institutional review board–approved study, 30 patients (mean age, 79 years; 12 women; mean body mass index, 28 kg/m2) with severe aortic stenosis undergoing PCD-CT as part of their preprocedural workup for transcatheter aortic valve replacement were included. The scan protocol consisted of a nonenhanced calcium-scoring scan, coronary CT angiograph...
Source: Investigative Radiology - May 8, 2022 Category: Radiology Tags: Original Articles Source Type: research

Photon-Counting Detector CT-Based Vascular Calcium Removal Algorithm: Assessment Using a Cardiac Motion Phantom
Objectives The diagnostic performance of coronary computed tomography angiography is known to be negatively affected by the presence of severely calcified plaques in the coronary arteries. In this article, the performance of a novel image reconstruction algorithm (PureLumen) based on spectral CT data of a first-generation dual-source photon-counting detector computed tomography (PCD-CT) system was assessed in a phantom study. PureLumen tries to remove only the calcified contributions from the image while leaving the rest unmodified. Materials and Methods The study uses 2 iodine contrast filled vessel phantoms (d...
Source: Investigative Radiology - May 8, 2022 Category: Radiology Tags: Original Articles Source Type: research

Basic and Advanced Metal-Artifact Reduction Techniques at Ultra-High Field 7-T Magnetic Resonance Imaging—Phantom Study Investigating Feasibility and Efficacy
Objectives The aim of this study was to demonstrate the feasibility and efficacy of basic (increased receive bandwidth) and advanced (view-angle tilting [VAT] and slice-encoding for metal artifact correction [SEMAC]) techniques for metal-artifact reduction in ultra-high field 7-T magnetic resonance imaging (MRI). Materials and Methods In this experimental study, we performed 7-T MRI of titanium alloy phantom models composed of a spinal pedicle screw (phantom 1) and an intervertebral cage (phantom 2) centered in a rectangular LEGO frame, embedded in deionized-water-gadolinium (0.1 mmol/L) solution. The following ...
Source: Investigative Radiology - May 8, 2022 Category: Radiology Tags: Original Articles Source Type: research

Impact of Deep Learning Reconstruction Combined With a Sharpening Filter on Single-Shot Fast Spin-Echo T2-Weighted Magnetic Resonance Imaging of the Uterus
This study aimed to evaluate the effects of deep learning (DL) reconstruction and a postprocessing sharpening filter on the image quality of single-shot fast spin-echo (SSFSE) T2-weighted imaging (T2WI) of the uterus. Materials and Methods Fifty consecutive patients who underwent pelvic magnetic resonance imaging were included. Parasagittal T2WI with a slice thickness of 4 mm was obtained with the periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) and SSFSE sequences (mean scan time, 204 and 22 seconds, respectively). The following 3 types of SSFSE images were reconstructed, and...
Source: Investigative Radiology - May 8, 2022 Category: Radiology Tags: Original Articles Source Type: research

The Compressed Sensing MP2RAGE as a Surrogate to the MPRAGE for Neuroimaging at 3 T
Objectives The magnetization-prepared 2 rapid acquisition gradient echo (MP2RAGE) sequence provides quantitative T1 maps in addition to high-contrast morphological images. Advanced acceleration techniques such as compressed sensing (CS) allow its acquisition time to be compatible with clinical applications. To consider its routine use in future neuroimaging protocols, the repeatability of the segmented brain structures was evaluated and compared with the standard morphological sequence (magnetization-prepared rapid gradient echo [MPRAGE]). The repeatability of the T1 measurements was also assessed. Materials and Met...
Source: Investigative Radiology - May 8, 2022 Category: Radiology Tags: Original Articles Source Type: research

Impact of Contrast Enhancement and Virtual Monoenergetic Image Energy Levels on Emphysema Quantification: Experience With Photon-Counting Detector Computed Tomography
Purpose The aim of this study was to evaluate the impact of contrast enhancement and different virtual monoenergetic image energies on automatized emphysema quantification with photon-counting detector computed tomography (PCD-CT). Material and Methods Sixty patients who underwent contrast-enhanced chest CT on a first-generation, clinical dual-source PCD-CT were retrospectively included. Scans were performed in the multienergy (QuantumPlus) mode at 120 kV with weight-adjusted intravenous contrast agent. Virtual noncontrast (VNC) images as well as virtual monoenergetic images (VMIs) from 40 to 80 keV obtained in ...
Source: Investigative Radiology - May 8, 2022 Category: Radiology Tags: Original Articles Source Type: research

Individualized Scan Protocols in Abdominal Computed Tomography: Radiation Versus Contrast Media Dose Optimization
Background In contrast-enhanced abdominal computed tomography (CT), radiation and contrast media (CM) injection protocols are closely linked to each other, and therefore a combination is the basis for achieving optimal image quality. However, most studies focus on optimizing one or the other parameter separately. Purpose Reducing radiation dose may be most important for a young patient or a population in need of repetitive scanning, whereas CM reduction might be key in a population with insufficient renal function. The recently introduced technical solution, in the form of an automated tube voltage selection (AT...
Source: Investigative Radiology - May 8, 2022 Category: Radiology Tags: Original Articles Source Type: research

Estimation of Contrast Agent Concentration in DCE-MRI Using 2 Flip Angles
Conclusions This study substantiates the feasibility of using the 2-FA approach during DCE-MRI scan to estimate [Gd] in the plasma without using an extra scan to perform precontrast T1 measurements. (Source: Investigative Radiology)
Source: Investigative Radiology - April 9, 2022 Category: Radiology Tags: Original Articles Source Type: research

Reliable Assessment of Swine Renal Fibrosis Using Quantitative Magnetization Transfer Imaging
Objectives Quantitative magnetization transfer (qMT) is useful for measurement of murine renal fibrosis at high and ultrahigh field strengths. However, its utility at clinical field strengths and in human-like kidneys remains unknown. We tested the hypothesis that qMT would successfully detect fibrosis in swine kidneys with unilateral renal artery stenosis (RAS) at 3.0 T. Methods The qMT protocol is composed of MT scans with variable flip angles and offset frequencies, and of B0, B1, and T1 mapping. Pigs were scanned 10 weeks after RAS or control. A 2-pool model was used to fit the bound pool fraction f of the r...
Source: Investigative Radiology - April 9, 2022 Category: Radiology Tags: Original Articles Source Type: research

Deep Learning Algorithm for Fully Automated Detection of Small (≤4 cm) Renal Cell Carcinoma in Contrast-Enhanced Computed Tomography Using a Multicenter Database
Conclusions The proposed deep learning–based algorithm achieved high accuracy, sensitivity, specificity, and AUC for the detection of small RCCs with both internal and external validations, suggesting that this algorithm could contribute to the early detection of small RCCs. (Source: Investigative Radiology)
Source: Investigative Radiology - April 9, 2022 Category: Radiology Tags: Original Articles Source Type: research

Risk of Hypersensitivity Reactions to Iopromide in Children and Elderly: An Analysis of 132,850 Patients From 4 Observational Studies and Pharmacovigilance Covering >288 Million Administrations
Purpose The aim of this study was to analyze the risk of hypersensitivity reactions (HSRs) to iopromide in children and elderly patients in comparison to adults. Materials and Methods Four observational studies were pooled and analyzed (analysis I). In addition, spontaneous reports from 1985 to 2020 from the pharmacovigilance database were evaluated (analysis II). All patients received iopromide for angiographic procedures or contrast-enhanced computed tomography in various indications. In analysis I, a nested case-control analysis, including a multivariable logistic regression model, based on pooled observation...
Source: Investigative Radiology - April 9, 2022 Category: Radiology Tags: Original Articles Source Type: research

Deep Learning-Based Image Conversion Improves the Reproducibility of Computed Tomography Radiomics Features: A Phantom Study
Conclusions Our study demonstrated that a deep learning model for image conversion can improve the reproducibility of radiomics features across various CT protocols, reconstruction kernels, and CT scanners. (Source: Investigative Radiology)
Source: Investigative Radiology - April 9, 2022 Category: Radiology Tags: Original Articles Source Type: research

Dual-Echo Turbo Spin Echo and 12-Echo Multi Spin Echo Sequences as Equivalent Techniques for Obtaining T2-Relaxometry Data: Application in Symptomatic and Asymptomatic Hereditary Transthyretin Amyloidosis as a Surrogate Disease
Objectives Multi spin echo (MSE) sequences are often used for obtaining T2-relaxometry data as they provide defined echo times (TEs). Due to their time-consuming acquisition, they are frequently replaced by turbo spin echo (TSE) sequences that in turn bear the risk of systematic errors when analyzing small structures or lesions. With this study, we aim to test whether T2-relaxometry data derived from either dual-echo TSE or 12-echo MSE sequences are equivalent for quantifying peripheral nerve lesions. Hereditary transthyretin (ATTRv) amyloidosis was chosen as a surrogate disease, as it allows the inclusion of both asym...
Source: Investigative Radiology - April 9, 2022 Category: Radiology Tags: Original Articles Source Type: research

Severity of Flare Reactions in Diethylenetriamine Pentaacetate Chelations: Report on Different Immune Dampening Strategies in Clinical Practice
Conclusion Based on early clinical experience, EHMR seems to manage flare reactions in DTPA chelation well. This strategy may represent the first standard therapy in patients with GDD. (Source: Investigative Radiology)
Source: Investigative Radiology - April 9, 2022 Category: Radiology Tags: Original Articles Source Type: research