74,286 results on '"Contrast Media"'
Search Results
2. Ovarian torsion: incremental role of contrast-enhanced ultrasound
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Shivani Gupta, Smita Manchanda, and Vatsla Dadhwal
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Ovarian Torsion ,Humans ,Contrast Media ,Female ,Ultrasonography, Doppler ,General Medicine ,Magnetic Resonance Imaging ,Ultrasonography - Abstract
We highlight the role of contrast-enhanced ultrasound (CEUS) as a supplementary modality to ultrasound (USG) examination in ovarian torsion in this case report. The reported patient had clinical history suspicious of ovarian torsion; however, USG and Doppler flow study findings were equivocal. CEUS was performed to solve the diagnostic dilemma and to know the status of ovarian parenchymal viability which revealed non-enhancement of the ovarian cyst wall and pedicle throughout the USG examination thus establishing the diagnosis of non-viable or infarcted ovarian parenchyma. The per operative and histopathology findings were consistent with our CEUS findings. CEUS is an emerging promising modality which provides information regarding parenchymal perfusion, resulting in a reliable diagnosis of ovarian torsion along with information on ovarian parenchymal viability. This ability makes CEUS equivalent to contrast-enhanced CT or MRI.
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- 2024
3. Appearance of fat necrosis on contrast-enhanced spectral mammography
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Natalia Lucia Garibotto, Julian K K Chan, and Donna Taylor
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Contrast Media ,Humans ,Breast Neoplasms ,Female ,General Medicine ,Breast ,Fat Necrosis ,Sensitivity and Specificity ,Mammography - Published
- 2024
4. Comparing Cardiac Mechanics and Myocardial Fibrosis in DBD and DCD Heart Transplant Recipients
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MATTHEW K BURRAGE, CAITLIN CHESHIRE, CONG YING HEY, SAIMA AZAM, WILLIAM D WATSON, SAI BHAGRA, MARIUS BERMAN, LUIGIA D'ERRICO, David P Jenkins, PRADEEP KAUL, STEPHEN LARGE, CLIVE LEWIS, LUIS MARTINEZ, SIMON MESSER, ARAVINDA PAGE, JAYAN PARAMESHWAR, STEPHEN PETTIT, MUHAMMAD RAFIQ, STEVEN TSUI, KATHARINE TWEED, JONATHAN R WEIR-MCCALL, ANNA KYDD, Weir-McCall, Jonathan [0000-0001-5842-842X], and Apollo - University of Cambridge Repository
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Male ,Heart Failure ,fibrosis ,Contrast Media ,Gadolinium ,heart transplantation ,Tissue Donors ,myocardial strain ,DCD ,Humans ,Cardiovascular magnetic resonance ,DBD ,Female ,Cardiomyopathies ,Cardiology and Cardiovascular Medicine ,Retrospective Studies - Abstract
BACKGROUND: Heart transplantation (HTx) after donation after circulatory death (DCD) is an expanding practice but is associated with increased warm ischemic time. The impact of DCD HTx on cardiac mechanics and myocardial fibrosis has not been reported. We aimed to compare cardiac mechanics and myocardial fibrosis using cardiovascular magnetic resonance (CMR) imaging in donation after brain death (DBD) and DCD HTx recipients and healthy controls. METHODS AND RESULTS: Consecutive HTx recipients between March 2015 and March 2021 who underwent routine surveillance CMR imaging were included. Cardiac mechanics were assessed using CMR feature tracking to compute global longitudinal strain, global circumferential strain, and right ventricular free-wall longitudinal myocardial strain. Fibrosis was assessed using late gadolinium enhancement imaging and estimation of extracellular volume. There were 82 (DBD n = 42, DCD n = 40) HTx recipients (aged 53 years, interquartile range 41-59 years, 24% female) who underwent CMR imaging at median of 9 months (interquartile range 6-14 months) after transplantation. HTx recipients had increased extracellular volume (29.7 ± 3.6%) compared with normal ranges (25.9%, interquartile range 25.4-26.5). Myocardial strain was impaired after transplantation compared with controls (global longitudinal strain -12.6 ± 3.1% vs -17.2 ± 1.8%, P < .0001; global circumferential strain -16.9 ± 3.1% vs -19.2 ± 2.0%, P = .002; right ventricular free-wall longitudinal strain -15.7 ± 4.5% vs -21.6 ± 4.7%, P < .0001). There were no differences in fibrosis burden (extracellular volume 30.6 ± 4.4% vs 29.2 ± 3.2%; P = .39) or cardiac mechanics (global longitudinal strain -13.1 ± 3.0% vs -12.1 ± 3.1%, P = .14; global circumferential strain -17.3 ± 2.9% vs -16.6 ± 3.1%, P = .27; right ventricular free-wall longitudinal strain -15.9 ± 4.9% vs -15.5 ± 4.1%, P = .71) between DCD and DBD HTx. CONCLUSIONS: HTx recipients have impaired cardiac mechanics compared with controls, with increased myocardial fibrosis. There were no differences in early CMR imaging characteristics between DBD and DCD heart transplants, providing further evidence that DCD and DBD HTx outcomes are comparable.
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- 2023
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5. Effect of contrast medium on early detection and analysis of mediastinal lymph nodes in computed tomography
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Merve Polat, EMRAH MELETLİOĞLU, and GÖKHAN POLAT
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Contrast media ,Mediastinum ,General Medicine ,Lymph nodes ,Computed tomography - Abstract
SUMMARY OBJECTIVE: This study aimed to evaluate the diagnostic efficiency of contrast-to-noise and signal-to-noise ratios created by the contrast medium in detecting lymph nodes. METHODS: In this study, 57 short-axis subcentimeter lymph nodes in 40 cardiac computed tomography patients with noncontrast- and contrast-enhanced phases were evaluated. The contrast-to-noise ratios and signal-to-noise ratios of noncontrast- and contrast-enhanced lymph node-mediastinal fat and aortic-mediastinal fat tissues were determined. In addition, lymph nodes in noncontrast- and contrast-enhanced series were evaluated subjectively. RESULTS: There was a significant difference in lymph node-mediastinal fat signal-to-noise values between the contrast and noncontrast phases (p=0.0002). In the contrast phase, aortic density values were found to be 322.04±18.51 HU, lymph node density values were 76.41±23.41 HU, and mediastinal adipose tissue density values were −65.73±22.96 HU. Aortic-mediastinal fat contrast-to-noise ratio value was 20.23±6.92 and the lymph node-mediastinal fat contrast-to-noise ratio value was 6.43±2.07. A significant and moderate correlation was observed between aortic-mediastinal fat and lymph node-mediastinal fat contrast-to-noise ratio values in the contrast phase (r=0.605; p
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- 2023
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6. Joint Optimization of k-t Sampling Pattern and Reconstruction of DCE MRI for Pharmacokinetic Parameter Estimation
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Jiaren Zou and Yue Cao
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Radiological and Ultrasound Technology ,Humans ,Contrast Media ,Electrical and Electronic Engineering ,Magnetic Resonance Imaging ,Software ,Computer Science Applications - Abstract
This work proposes to develop and evaluate a deep learning framework that jointly optimizes k-t sampling patterns and reconstruction for head and neck dynamic contrast-enhanced (DCE) MRI aiming to reduce bias and uncertainty of pharmacokinetic (PK) parameter estimation. 2D Cartesian phase encoding k-space subsampling patterns for a 3D spoiled gradient recalled echo (SPGR) sequence along a time course of DCE MRI were jointly optimized in a deep learning-based dynamic MRI reconstruction network by a loss function concerning both reconstruction image quality and PK parameter estimation accuracy. During training, temporal k-space data sharing scheme was optimized as well. The proposed method was trained and tested by multi-coil complex digital reference objects of DCE images (mcDROs). The PK parameters estimated by the proposed method were compared with two published iterative DCE MRI reconstruction schemes using normalized root mean squared errors (NRMSEs) and Bland-Altman analysis at temporal resolutions of [Formula: see text] = 2s, 3s, 4s, and 5s, which correspond to undersampling rates of R = 50, 34, 25, and 20. The proposed method achieved low PK parameter NRMSEs at all four temporal resolutions compared with the benchmark methods on testing mcDROs. The Bland-Altman plots demonstrated that the proposed method reduced PK parameter estimation bias and uncertainty in tumor regions at temporal resolution of 2s. The proposed method also showed robustness to contrast arrival timing variations across patients. This work provides a potential way to increase PK parameter estimation accuracy and precision, and thus facilitate the clinical translation of DCE MRI.
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- 2023
7. Radial spoiled gradient T1 weighted imaging of the internal auditory canal: Is Scarpa's ganglion now an expected finding and source of fundal enhancement?
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Kamran Munawar, Eytan Raz, Seena Dehkharghani, Girish M Fatterpekar, Tobias K Block, and Yvonne W Lui
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Imaging, Three-Dimensional ,Contrast Media ,Humans ,Radiology, Nuclear Medicine and imaging ,Neurology (clinical) ,General Medicine ,Vestibular Nerve ,Magnetic Resonance Imaging - Abstract
StarVIBE is a 3D gradient-echo sequence with a radial, stack-of-stars acquisition having spatial resolution and tissue contrast. With newer sequences, it is important to be familiar with sequence tissue contrasts and appearance of anatomical variants. We evaluated 450 patients utilizing this sequence; 35 patients demonstrated fluffy “cotton wool” enhancement at the internal auditory canal fundus without clear pathology. We favor this represents anatomic neurovascular enhancement that StarVIBE is sensitive to and is a touch-me-not finding.
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- 2023
8. Perfluorocarbon nanodroplet size, acoustic vaporization, and inertial cavitation affected by lipid shell composition in vitro
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Phoebe J. Welch, David S. Li, Craig R. Forest, Lilo D. Pozzo, and Chengzhi Shi
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Fluorocarbons ,Microbubbles ,Acoustics and Ultrasonics ,Arts and Humanities (miscellaneous) ,Contrast Media ,Acoustics ,Volatilization ,Phospholipids - Abstract
Perfluorocarbon nanodroplets (PFCnDs) are ultrasound contrast agents that phase-transition from liquid nanodroplets to gas microbubbles when activated by laser irradiation or insonated with an ultrasound pulse. The dynamics of PFCnDs can vary drastically depending on the nanodroplet composition, including the lipid shell properties. In this paper, we investigate the effect of varying the ratio of PEGylated to non-PEGylated phospholipids in the outer shell of PFCnDs on the acoustic nanodroplet vaporization (liquid to gas phase transition) and inertial cavitation (rapid collapse of the vaporized nanodroplets) dynamics in vitro when insonated with focused ultrasound. Nanodroplets with a high concentration of PEGylated lipids had larger diameters and exhibited greater variance in size distribution compared to nanodroplets with lower proportions of PEGylated lipids in the lipid shell. PFCnDs with a lipid shell composed of 50:50 PEGylated to non-PEGylated lipids yielded the highest B-mode image intensity and duration, as well as the greatest pressure difference between acoustic droplet vaporization onset and inertial cavitation onset. We demonstrate that slight changes in lipid shell composition of PFCnDs can significantly impact droplet phase transitioning and inertial cavitation dynamics. These findings can help guide researchers to fabricate PFCnDs with optimized compositions for their specific applications.
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- 2023
9. Displacement of a peripherally inserted central catheter after injection of contrast media
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Naoya Yama, Hiroomi Tatsumi, Masayuki Akatsuka, and Yoshiki Masuda
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medicine.medical_specialty ,Catheterization, Central Venous ,Bladder cancer ,business.industry ,Contrast Media ,General Medicine ,Medication administration ,medicine.disease ,Peripherally inserted central catheter ,Postoperative management ,Surgery ,Sepsis ,Catheters, Indwelling ,Superior vena cava ,Risk Factors ,Catheterization, Peripheral ,cardiovascular system ,Medicine ,Central Venous Catheters ,Humans ,Right basilic vein ,Displacement (orthopedic surgery) ,business - Abstract
A peripherally inserted central catheter (PICC) was inserted through the right basilic vein and placed within the superior vena cava of a patient for fluid and medication administration during postoperative management of bladder cancer. Following the development of sepsis, contrast-enhanced CT was
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- 2023
10. Scar imaging in the dyssynchronous left ventricle: Accuracy of myocardial metabolism by positron emission tomography and function by echocardiographic strain
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Camilla Kjellstad Larsen, Elena Galli, Jürgen Duchenne, John M. Aalen, Caroline Stokke, Jan Gunnar Fjeld, Ganna Degtiarova, Piet Claus, Olivier Gheysens, Jorg Saberniak, Per Anton Sirnes, Erik Lyseggen, Jan Bogaert, Erik Kongsgaard, Martin Penicka, Jens-Uwe Voigt, Erwan Donal, Einar Hopp, Otto A. Smiseth, Oslo University Hospital [Oslo], University of Oslo (UiO), CHU Pontchaillou [Rennes], Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Akershus University Hospital [Lørenskog], University Hospitals Leuven [Leuven], Laboratoire Traitement du Signal et de l'Image (LTSI), Université de Rennes (UR)-Institut National de la Santé et de la Recherche Médicale (INSERM), Fonds Wetenschappelijk Onderzoek, FWO: 12ZZN22N, FKM1832917N, KU Leuven: OT12/084, Helse Sør-Øst RHF, sorost, and Nasjonalforeningen for Folkehelsen
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Glucose metabolism ,Positron emission tomography ,Late gadolinium enhancement cardiac magnetic resonance ,Heart Ventricles ,Contrast Media ,Gadolinium ,Heart failure ,Myocardial scar ,Strain ,Cardiac Resynchronization Therapy ,Cicatrix ,Dyssynchrony ,Speckle tracking echocardiography ,[SDV.MHEP.CSC]Life Sciences [q-bio]/Human health and pathology/Cardiology and cardiovascular system ,Fluorodeoxyglucose F18 ,Echocardiography ,Positron-Emission Tomography ,Humans ,Prospective Studies ,Cardiology and Cardiovascular Medicine - Abstract
PURPOSE: Response to cardiac resynchronization therapy (CRT) is reduced in patients with high left ventricular (LV) scar burden, in particular when scar is located in the LV lateral wall or septum. Late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) can identity scar, but is not feasible in all patients. This study investigates if myocardial metabolism by 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) and contractile function by echocardiographic strain are alternatives to LGE-CMR. METHODS: In a prospective multicenter study, 132 CRT candidates (91% with left bundle branch block) were studied by speckle tracking strain echocardiography, and 53 of these by FDG-PET. Regional myocardial FDG metabolism and peak systolic strain were compared to LGE-CMR as reference method. RESULTS: Reduced FDG metabolism (10% could rule out transmural scar with high sensitivity (80%) and high negative predictive value (96%). Neither FDG-PET nor strain identified septal scars (for both, AUC
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- 2023
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11. MR Imaging of Endometriosis of the Adnexa
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Michelle D, Sakala, Priyanka, Jha, Angela, Tong, Myles T, Taffel, and Myra K, Feldman
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Diagnosis, Differential ,Endometrium ,Endometriosis ,Humans ,Contrast Media ,Female ,Radiology, Nuclear Medicine and imaging ,Magnetic Resonance Imaging - Abstract
Endometriosis is the presence of ectopic endometrial glands outside of the uterus. MR imaging is particularly useful for characterizing deep infiltrating endometriosis but can also be useful in characterizing endometriomas and hematosalpinges, characterizing broad ligament deposits, assessing for endometriosis-associated malignancy, and differentiating malignancy from decidualized endometriomas. Masses and cysts with hemorrhagic or proteinaceous contents can sometimes be difficult to distinguish from endometriomas. Imaging protocols should include pre-contrast T1-weighted imaging with fat saturation, T2-weighted imaging without fat saturation, opposed- and in-phase or Dixon imaging, administration of contrast media, and subtraction imaging.
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- 2023
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12. Reduction of Gadolinium-Based Contrast Agents in MRI Using Convolutional Neural Networks and Different Input Protocols
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Robert Haase, Thomas Pinetz, Zeynep Bendella, Erich Kobler, Daniel Paech, Wolfgang Block, Alexander Effland, Alexander Radbruch, and Katerina Deike-Hofmann
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methods [Magnetic Resonance Imaging] ,Humans ,Contrast Media ,Female ,Gadolinium ,Radiology, Nuclear Medicine and imaging ,ddc:610 ,methods [Image Enhancement] ,Neural Networks, Computer ,General Medicine - Abstract
The purpose of this study was to implement a state-of-the-art convolutional neural network used to synthesize artificial T1-weighted (T1w) full-dose images from corresponding noncontrast and low-dose images (using various settings of input sequences) and test its performance on a patient population acquired prospectively.In this monocentric, institutional review board-approved study, a total of 138 participants were included who received an adapted imaging protocol with acquisition of a T1w low dose after administration of 10% of the standard dose and acquisition of a T1w full dose after administration of the remaining 90% of the standard dose of a gadolinium-containing contrast agent. A total of 83 participants formed the training sample (51.7 ± 16.5 years, 36 women), 25 the validation sample (55.3 ± 16.4 years, 11 women), and 30 the test sample (55.0 ± 15.0 years, 9 women). Four input settings were differentiated: only the T1w noncontrast and T1w low-dose images (standard setting), only the T1w noncontrast and T1w low-dose images with a prolonged postinjection time of 5 minutes (5-minute setting), multiple noncontrast sequences (T1w, T2w, diffusion) and the T1w low-dose images (extended setting), and only noncontrast sequences (T1w, T2w, diffusion) were used (zero-dose setting). For each setting, a deep neural network was trained to synthesize artificial T1w full-dose images, which were assessed on the test sample using an objective evaluation based on quantitative metrics and a subjective evaluation through a reader-based study. Three readers scored the overall image quality, the interchangeability in regard to the clinical conclusion compared with the true T1w full-dose sequence, the contrast enhancement of lesions, and their conformity to the respective references in the true T1w full dose.Quantitative analysis of the artificial T1w full-dose images of the standard setting provided a peak signal-to-noise ratio of 33.39 ± 0.62 (corresponding to an average improvement of the low-dose sequences of 5.2 dB) and a structural similarity index measure of 0.938 ± 0.005. In the 4-fold cross-validation, the extended setting yielded similar performance to the standard setting in terms of peak signal-to-noise ratio ( P = 0.20), but a slight improvement in structural similarity index measure ( P < 0.0001). For all settings, the reader study found comparable overall image quality between the original and artificial T1w full-dose images. The proportion of scans scored as fully or mostly interchangeable was 55%, 58%, 43%, and 3% and the average counts of false positives per case were 0.42 ± 0.83, 0.34 ± 0.71, 0.82 ± 1.15, and 2.00 ± 1.07 for the standard, 5-minute, extended, and zero-dose setting, respectively. Using a 5-point Likert scale (0 to 4, 0 being the worst), all settings of synthesized full-dose images showed significantly poorer contrast enhancement of lesions compared with the original full-dose sequence (difference of average degree of contrast enhancement-standard: -0.97 ± 0.83, P =
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- 2023
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13. Ultrasound Contrast Stability for Urinary Bladder Pressure Measurement
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Kourosh Kalayeh, J. Brian Fowlkes, Jake Claflin, Mario L. Fabiilli, William W. Schultz, and Bryan S. Sack
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Microbubbles ,Acoustics and Ultrasonics ,Radiological and Ultrasound Technology ,Urinary Bladder ,Biophysics ,Contrast Media ,Radiology, Nuclear Medicine and imaging ,Ultrasonography ,Pelvis - Abstract
The goal of this study was to evaluate ultrasound contrast microbubbles (MB) stability during a typical cystometrogram (CMG) for bladder pressure measurement application using the subharmonic-aided pressure estimation technique. A detailed study of MB stability was required given two unique characteristics of this application: first, bulk infusion of MBs into the bladder through the CMG infusion system, and second, duration of a typical CMG which may last up to 30 min. To do so, a series of size measurement and contrast-enhanced ultrasound imaging studies under different conditions were performed and the effects of variables that we hypothesized have an effect on MB stability, namely, i) IV bag air headspace, ii) MB dilution factor, and iii) CMG infusion system were investigated. The results verified that air volume in intravenous (IV) bag headspace was not enough to have a significant effect on MB stability during a CMG. We also showed that higher MB dosage results in a more stable condition. Finally, the results indicated that the CMG infusion system adversely affects MB stability. In summary, to ensure MB stability during the entire duration of a CMG, lower filling rates (limited by estimated bladder capacity in clinical applications) and/or higher MB dosage (limited by FDA regulations and shadowing artifact) and/or the consideration of alternative catheter design may be needed.
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- 2023
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14. Quantitative Evaluation of late Gadolinium Enhancement to the Differential Diagnosis of Prostate Cancer and Prostatitis in mpMRI
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Huseyin, Aydin, Kahraman, Topsakal, Veysel Atilla, Ayyildiz, Hasan, Aydin, and Adnan, Karaibrahimoglu
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Male ,Diagnosis, Differential ,Humans ,Prostatic Neoplasms ,Contrast Media ,Gadolinium ,General Medicine ,Multiparametric Magnetic Resonance Imaging ,Magnetic Resonance Imaging ,Prostatitis ,Retrospective Studies - Abstract
To evaluate the late gadolinium enhancement ratio (LGER) quantitatively in late post-contrast images in multiparametric prostate MRI (mpMRI) for the differential diagnosis of chronic prostatitis and prostate cancer (PCa).Descriptive study.Department of Radiology, Suleyman Demirel University, Isparta, Turkey, from January 2018 to October 2021.The data of 111 patients with a diagnosis of PCa and chronic prostatitis, were retrospectively analysed who underwent mpMRI of the prostate were retrospectively analysed. Histopathological verification was available in 57 of 57 prostate carcinoma patients and 20 of 54 chronic prostatitis cases. The detection of lesions from the images and the correlation of the detected lesions with their histopathological diagnoses were made by the joint decision of two radiologists. The LGER measurements were made independently by both radiologists. Signal intensity (SI) values of the lesions were obtained by placing a hand-drawn ROI on pre-contrast and late post-contrast images. Late enhancement ratio was calculated from the ratio of the difference between the pre- and post-contrast SI values to the pre-contrast SI values. The LGER values obtained were statistically compared between the pathologically proven PCa and chronic prostatitis patient groups.The prostatitis LGER values (103.40 ± 31.54%) were significantly higher than the PCa values (79.71±27.39, p0.001). The LGER values of lesions with a Gleason score7 were lower than those of lesions scoring ≥7 (p = 0.004). The LGER values of PI-RADS-3 PCa lesions were lower than those of PI-RADS-4 and PI-RADS-5 (p = 0.002). In the late post-contrast phase, low signal measurements in PI-RADS-3 lesions excluded the presence of prostatitis.Late contrast enhancement quantitative SI measurements performed in the late contrast phase of mpMRI may enable the differential diagnosis of PCa/prostatitis and a more accurate evaluation of PI-RADS scores in terms of malignancy.Prostate cancer, Prostatitis, Gadolinium, Dynamic contrast-enhanced magnetic resonance imaging.
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- 2023
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15. Safety and Feasibility of Contrast-Enhanced Computed Tomography with a Nanoparticle Contrast Agent for Evaluation of Diethylnitrosamine-Induced Liver Tumors in a Rat Model
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Takehito Nota, Ken Kageyama, Akira Yamamoto, Anna Kakehashi, Hiroki Yonezawa, Atsushi Jogo, Etsuji Sohgawa, Kazuki Murai, Satoyuki Ogawa, and Yukio Miki
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Male ,Carcinoma, Hepatocellular ,Liver Neoplasms ,Animals ,Contrast Media ,Feasibility Studies ,Nanoparticles ,Water ,Diethylnitrosamine ,Radiology, Nuclear Medicine and imaging ,Tomography, X-Ray Computed ,Rats, Inbred F344 ,Rats - Abstract
Safety and feasibility of contrast-enhanced computed tomography (CECT) with a nanoparticulate contrast agent, ExiTron nano 12000, was evaluated in a rat liver tumor model.This study employed eighteen 8-week-old male F344 rats. Six rats given tap water for 8 weeks further divided into two: Control group and Normal Liver with CECT group. Six rats each were given tap water containing diethylnitrosamine (DEN) at 100 ppm for 8 or 14 weeks; Adenoma group and Hepatocellular carcinoma (HCC) group, respectively. Biochemical marker values and adverse events were evaluated after CT imaging. ExiTron nano 12000 was evaluated for the hepatic contrast enhancement, and the detection and measurement of liver nodules by CECT after 8- and 14-weeks administration of DEN. Post-mortem liver specimens were evaluated by hematoxylin-eosin (HE) staining, and the number and size of liver nodules were measured. The HCC group was evaluated for diagnostic concordance between HE-stained and CECT-detected nodules.The contrast agent enhanced liver and was tolerated after CECT in 15 rats. Biochemical parameter values did not differ significantly between the Control and Normal Liver groups. The numbers of CECT-detected nodules in the Adenoma and HCC groups were 14.8 ± 5.1, and 32.4 ± 8.1, respectively. The HCC group had 3.6 ± 2.7 of pathological HCCs, which were identified by CECT. The size of CECT-detected HCCs correlated significantly with that of pathological HCCs (r = 0.966, p0.0001).CECT with ExiTron nano 12000 is a safe and feasible method to measure tumors in a rat liver tumor model.
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- 2023
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16. Significance of Spontaneous Echocardiographic Contrast in Transcatheter Edge-to-Edge Repair for Mitral Regurgitation
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Hirotomo Sato, João L. Cavalcante, Maurice Enriquez-Sarano, Richard Bae, Miho Fukui, Vinayak N. Bapat, and Paul Sorajja
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Aged, 80 and over ,Male ,Heart Valve Prosthesis Implantation ,Cardiac Catheterization ,Mitral Valve Insufficiency ,Contrast Media ,Treatment Outcome ,Echocardiography ,Risk Factors ,Humans ,Mitral Valve ,Female ,Radiology, Nuclear Medicine and imaging ,Cardiology and Cardiovascular Medicine - Abstract
Spontaneous echocardiographic contrast (SEC) in the left atrium can occur with transcatheter edge-to-edge repair (TEER), but the clinical significance is unknown.The authors examined the clinical association of the procedural appearance of SEC in 316 patients (median age, 82 years; interquartile range, 76-86 years; 43.4% women) undergoing TEER with the MitraClip for mitral regurgitation. Acute, 30-day, and 2-year clinical outcomes were analyzed.SEC was common, occurring following device implantation in 106 patients (34%). Although the occurrence of SEC was not related to clinical characteristics, such as atrial fibrillation, anticoagulant use, or left ventricular function, there was a strong relation to beneficial outcomes with TEER. The frequency of optimal reduction in mitral regurgitation was higher in patients who had SEC (99.1% vs 72.9%, P .001). Survival was greater, with a 2-year estimate for freedom from all-cause mortality of 88.4% versus 71.5% (log-rank P = .004). Importantly, the higher survival observed in patients with SEC was present without increased rates of procedural complications or stroke and remained significant in multivariate analyses that adjusted for baseline clinical and echocardiographic variables (P = .01).The occurrence of SEC in patients with TEER is associated with beneficial acute and intermediate-term outcomes.
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- 2023
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17. Additional prognostic values of strain and strain rate over late gadolinium enhancement in hypertrophic cardiomyopathy patients
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Le, Qin, Siqi, Zhu, Peng, Liu, Lan, Zhu, Chihua, Chen, Shengjia, Gu, Wenjie, Yang, Mi, Zhou, and Fuhua, Yan
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Predictive Value of Tests ,Humans ,Contrast Media ,Magnetic Resonance Imaging, Cine ,Gadolinium ,Prospective Studies ,Cardiomyopathy, Hypertrophic ,Prognosis ,Cardiology and Cardiovascular Medicine ,Fibrosis - Abstract
Late gadolinium enhancement (LGE) has some shortcomings in the risk stratification in hypertrophic cardiomyopathy (HCM). Myocardial strain/strain rate (SR) can be acquired from unenhanced cardiovascular magnetic resonance (CMR) images and detect cardiac dysfunction sensitively. The present study aimed to evaluate the additional prognostic values of myocardial strain/SR beyond LGE for the risk stratification in patients with HCM.293 patients with HCM who underwent CMR were enrolled in this prospective study. LGE/left ventricular (LV) mass, LV global strain, and SR were acquired based on CMR. Also, conventional clinical, echocardiography, and CMR parameters and established risk factors for HCM were evaluated.14/293 patients had major adverse cardiovascular events (MACEs) during the median follow-up of 15.0 months, including eight all-cause deaths, four resuscitated cardiac arrests and two cardiac transplantations. Peak systolic (PS)-global longitudinal SR (GLSR) was independently associated with MACEs (hazard ratio: 15.297, P 0.001) after adjusting for conventional clinical characteristics, echocardiography, and CMR parameters. The model constructed by conventional variables plus PS-GLSR had significantly stronger predictive ability than the model constructed by conventional variables plus LGE/LV mass (C-statistic: 0.850 vs 0.708, P = 0.030). The addition of PS-GLSR to the conventional model also significantly improved the sensitivity (92.9% vs 71.4%) and specificity (71.0% vs 57.3%), and lowered false positives (81 patients vs 119 patients) compared to the addition of LGE/LV mass.LV PS-GLSR derived from CMR has the potential to be a novel biomarker for risk stratification of HCM and provide additional prognostic value over LGE/LV mass.
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- 2023
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18. Tumor-Attentive Segmentation-Guided GAN for Synthesizing Breast Contrast-Enhanced MRI Without Contrast Agents
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Eunjin Kim, Hwan-Ho Cho, Junmo Kwon, Young-Tack Oh, Eun Sook Ko, and Hyunjin Park
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Biomedical Engineering ,Humans ,Contrast Media ,Female ,Breast Neoplasms ,General Medicine ,Magnetic Resonance Imaging - Abstract
Breast dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is a sensitive imaging technique critical for breast cancer diagnosis. However, the administration of contrast agents poses a potential risk. This can be avoided if contrast-enhanced MRI can be obtained without using contrast agents. Thus, we aimed to generate T1-weighted contrast-enhanced MRI (ceT1) images from pre-contrast T1 weighted MRI (preT1) images in the breast.We proposed a generative adversarial network to synthesize ceT1 from preT1 breast images that adopted a local discriminator and segmentation task network to focus specifically on the tumor region in addition to the whole breast. The segmentation network performed a related task of segmentation of the tumor region, which allowed important tumor-related information to be enhanced. In addition, edge maps were included to provide explicit shape and structural information. Our approach was evaluated and compared with other methods in the local (n = 306) and external validation (n = 140) cohorts. Four evaluation metrics of normalized mean squared error (NRMSE), Pearson cross-correlation coefficients (CC), peak signal-to-noise ratio (PSNR), and structural similarity index map (SSIM) for the whole breast and tumor region were measured. An ablation study was performed to evaluate the incremental benefits of various components in our approach.Our approach performed the best with an NRMSE 25.65, PSNR 54.80 dB, SSIM 0.91, and CC 0.88 on average, in the local test set.Performance gains were replicated in the validation cohort.We hope that our method will help patients avoid potentially harmful contrast agents. Clinical and Translational Impact Statement-Contrast agents are necessary to obtain DCE-MRI which is essential in breast cancer diagnosis. However, administration of contrast agents may cause side effects such as nephrogenic systemic fibrosis and risk of toxic residue deposits. Our approach can generate DCE-MRI without contrast agents using a generative deep neural network. Thus, our approach could help patients avoid potentially harmful contrast agents resulting in an improved diagnosis and treatment workflow for breast cancer.
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- 2023
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19. Use of metformin in patients who require intravascular administration of a contrast agent
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Krzysztof Strojek, Dorota Stołtny, Marta Wróbel, and Dominika Rokicka
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Endocrinology ,Diabetes Mellitus, Type 2 ,Endocrinology, Diabetes and Metabolism ,Humans ,Hypoglycemic Agents ,Contrast Media ,Female ,Insulin Resistance ,Metformin ,Polycystic Ovary Syndrome - Abstract
Metformin is a drug that has been widely used around the world for many years. Due to its properties, metformin is used in the treatment of carbohydrate disorders (in type 2 diabetes, prediabetes) and in insulin resistance syndromes (including polycystic ovary syndrome). Many patients using metformin, due to complications of carbohydrate metabolism disorders, including cardiovascular complications or other accompanying diseases, require cardiological or radiological diagnostics related to the administration of a contrast agent. The aim of this study is to summarize the recommendations regarding the use of metformin before procedures involving the use of contrast agents and to share our own experience in this area, based on observations of a large group of patients with cardiological diseases hospitalized at the Silesian Centre for Heart Diseases in Zabrze.
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- 2022
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20. Clinical application of super sensitive microflow ultrasound on the detection of intraplaque neovascularization in patients with atheromatous carotid artery plaque
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Jin, Chen, Dandan, Liu, Jing, Wang, Wanji, Song, and Fang, Ma
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Carotid Artery Diseases ,Carotid Arteries ,Neovascularization, Pathologic ,Physiology ,Physiology (medical) ,Humans ,Contrast Media ,Carotid Stenosis ,Hematology ,Cardiology and Cardiovascular Medicine ,Plaque, Atherosclerotic ,Ultrasonography - Abstract
BACKGROUND: Contrast-enhanced ultrasound (CEUS) is a routine technique for detecting intraplaque neovascularization (IPN). However, the invasiveness and complexity of CEUS severely limit its clinical application. This article aims to investigate the application value of AngioPLUS (AP) technique in assessing IPN formation in patients with atheromatous (AS) carotid artery plaque. METHODS: Patients diagnosed with carotid artery atherosclerosis combined plaque formation were recruited and their demographic characteristics including serum fasting blood glucose (FBG), triglyceride (TG), and low-density lipoprotein (LDL) were collected. AP was used to scoring intraplaque microvascular flow (IMVF), measuring the thickness and length of the plaque and determining the number of IPN of the plaque. RESULTS: IMVF score evaluated by AP was positively correlated with plaque length, thickness, IPN number, serum TG, LDL and FBG levels in patients with carotid atherosclerosis with plaque. The evaluation results of CEUS score and IMVF classification detected by AP of plaques were consistent in patients with carotid atherosclerosis. CONCLUSION: IMVF scoring by AP is a promising approach to assess IPN and plaque status in patients with atheromatous carotid artery plaque.
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- 2022
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21. Evaluation of the Metabolic Activity of the Infiltration and Proliferation Areas of Hepatic Alveolar Echinococcosis in Rats Using Contrast-Enhanced Ultrasound
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Xiaorong, Wang, Lingfei, Yang, Lu, Chen, and Tao, Song
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Echinococcosis, Hepatic ,Infectious Diseases ,Virology ,Animals ,Contrast Media ,Parasitology ,Rats, Wistar ,Rats ,Ultrasonography ,Cell Proliferation - Abstract
This study evaluated the value of contrast-enhanced ultrasound (CEUS) in assessing the metabolic activity of infiltration and proliferation areas of hepatic alveolar echinococcosis (HAE) in rats. CEUS was performed on Wistar rats with HAE. The average grayscale value of the HAE lesion in peripheral infiltration and proliferation areas (PIPAs) and the adjacent normal liver tissue was analyzed quantitatively. Contrast imaging was classified as highly increased enhancement, moderately increased enhancement, and equal or decreased enhancement. Microvessel density (MVD) in the PIPAs was classified as strongly positive, moderately positive, and weakly positive. The metabolic activity of HAE in the PIPAs was classified as high activity, moderate activity, and low activity according to the MVD classification results. The kappa test was combined with the metabolic activity level of the PIPAs to analyze the consistency of CEUS intensity and MVD. CEUS can score the metabolic activity of the infiltration and proliferation areas around HAE lesions, and provides a basis for clinical treatment and follow-up visits. CEUS could be used as a more economical and effective imaging option for evaluating the metabolic activity of HAE lesions.
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- 2022
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22. Large Protein Assemblies for High-Relaxivity Contrast Agents: The Case of Gadolinium-Labeled Asparaginase
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Giulia Licciardi, Domenico Rizzo, Maria Salobehaj, Lara Massai, Andrea Geri, Luigi Messori, Enrico Ravera, Marco Fragai, and Giacomo Parigi
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Pharmacology ,Organic Chemistry ,Biomedical Engineering ,Contrast Media ,Asparaginase ,Pharmaceutical Science ,Gadolinium ,Bioengineering ,Magnetic Resonance Imaging ,Chelating Agents ,Biotechnology - Abstract
Biologics are emerging as the most important class of drugs and are used to treat a large variety of pathologies. Most of biologics are proteins administered in large amounts, either by intramuscular injection or by intravenous infusion. Asparaginase is a large tetrameric protein assembly, currently used against acute lymphoblastic leukemia. Here, a gadolinium(III)-DOTA derivative has been conjugated to asparaginase, and its relaxation properties have been investigated to assess its efficiency as a possible theranostic agent. The field-dependent
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- 2022
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23. Imaging perfusion changes in oncological clinical applications by hyperspectral imaging: a literature review
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Rok, Hren, Gregor, Sersa, Urban, Simoncic, and Matija, Milanic
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Diagnostic Imaging ,Oncology ,Phantoms, Imaging ,Animals ,Contrast Media ,Radiology, Nuclear Medicine and imaging ,Medical Oncology ,Mastectomy - Abstract
Background Hyperspectral imaging (HSI) is a promising imaging modality that uses visible light to obtain information about blood flow. It has the distinct advantage of being noncontact, nonionizing, and noninvasive without the need for a contrast agent. Among the many applications of HSI in the medical field are the detection of various types of tumors and the evaluation of their blood flow, as well as the healing processes of grafts and wounds. Since tumor perfusion is one of the critical factors in oncology, we assessed the value of HSI in quantifying perfusion changes during interventions in clinical oncology through a systematic review of the literature. Materials and methods The PubMed and Web of Science electronic databases were searched using the terms “hyperspectral imaging perfusion cancer” and “hyperspectral imaging resection cancer”. The inclusion criterion was the use of HSI in clinical oncology, meaning that all animal, phantom, ex vivo, experimental, research and development, and purely methodological studies were excluded. Results Twenty articles met the inclusion criteria. The anatomic locations of the neoplasms in the selected articles were as follows: kidneys (1 article), breasts (2 articles), eye (1 article), brain (4 articles), entire gastrointestinal (GI) tract (1 article), upper GI tract (5 articles), and lower GI tract (6 articles). Conclusions HSI is a potentially attractive imaging modality for clinical application in oncology, with assessment of mastectomy skin flap perfusion after reconstructive breast surgery and anastomotic perfusion during reconstruction of gastrointenstinal conduit as the most promising at present.
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- 2022
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24. Towards differentiation of brain tumor from radiation necrosis using multi-parametric MRI: Preliminary results at 4.7 T using rodent models
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Sean P. Devan, Xiaoyu Jiang, Hakmook Kang, Guozhen Luo, Jingping Xie, Zhongliang Zu, Ashley M. Stokes, John C. Gore, Colin D. McKnight, Austin N. Kirschner, and Junzhong Xu
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Necrosis ,Brain Neoplasms ,Biomedical Engineering ,Biophysics ,Animals ,Contrast Media ,Rodentia ,Radiology, Nuclear Medicine and imaging ,Multiparametric Magnetic Resonance Imaging ,Radiation Injuries ,Magnetic Resonance Imaging - Abstract
It remains a clinical challenge to differentiate brain tumors from radiation-induced necrosis in the brain. Despite significant improvements, no single MRI method has been validated adequately in the clinical setting.Multi-parametric MRI (mpMRI) was performed to differentiate 9L gliosarcoma from radiation necrosis in animal models. Five types of MRI methods probed complementary information on different scales i.e., TFor single MRI parameters, iAUC and ADC provide the best discrimination of radiation necrosis and brain tumor. For mpMRI, a combination of iAUC, ADC, and APT shows the best classification performance based on a two-step analysis with the Lasso and Ridge regressions.A general mpMRI approach is introduced to choosing candidate multiple MRI methods, identifying the most effective parameters from all the mpMRI parameters, and finding the appropriate combination of chosen parameters to maximize the classification performance to differentiate tumors from radiation necrosis.
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- 2022
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25. Radiomics analysis of short tau inversion recovery images in cardiac magnetic resonance for the prediction of late gadolinium enhancement in patients with acute myocarditis
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Armando Ugo, Cavallo, Carlo, Di Donna, Jacopo, Troisi, Cecilia, Cerimele, Matteo, Cesareni, Marcello, Chiocchi, Roberto, Floris, and Francesco, Garaci
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Magnetic Resonance Spectroscopy ,Radiomics ,Biomedical Engineering ,Biophysics ,Contrast Media ,Magnetic Resonance Imaging, Cine ,Gadolinium ,Myocarditis, cardiac magnetic resonance ,Magnetic Resonance Imaging ,cardiac magnetic resonance ,Myocarditis ,Settore MED/36 ,Predictive Value of Tests ,Humans ,Radiology, Nuclear Medicine and imaging - Abstract
Cardiac Magnetic Resonance (CMR) imaging is recommended as the reference diagnostic non-invasive modality for myocarditis but is often limited by patients' compliance. The purpose of this study is to evaluate the validity of Radiomics applied to Short Tau Inversion Recovery (STIR) sequences, in predicting the presence of LGE in patients with suspected acute myocarditis.171 STIR images on short-axis view were segmented with "MaZda" software ver 4.6, by placing a region of interest (ROI) on the left ventricle by two radiologists in consensus. Images were classified according to the presence of LGE in the equivalent short-axis T1-IR slice. A total of 337 ROI features were extracted for each image. Dataset was then split into two parts (train and test set) with 70:30 ratio.Eleven classification models were trained. An Ensemble Machine Learning (EML) model was obtained by averaging the predictions of models with accuracy on test set70%. The EML documented accuracy of 0.75, sensitivity of 0.8 and a specificity of 0.73 with a NPV of 0.81 and a PPV of 0.7, with AUC of 0.79 (95% CI: 0.66-0.92).Radiomics and machine learning analysis could be a promising approach in reducing scan times without reducing diagnostic accuracy in predicting LGE in patients with acute myocarditis.
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- 2022
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26. A Health System's Response to the Ongoing Global Shortage of Iodinated Contrast Media
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Izabella L. Barreto, Joseph R. Grajo, Daniel E. Brock, Laura Magnelli, Pratik Patel, and Bruno Hochhegger
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Humans ,Contrast Media ,COVID-19 ,Radiology, Nuclear Medicine and imaging ,Longitudinal Studies ,General Medicine ,Tomography, X-Ray Computed ,Pandemics - Abstract
A production facility shutdown related to containment measures during the COVID-19 pandemic has resulted in a global shortage of iodinated contrast media. This article describes the strategies implemented at one large U.S. health system to maintain care continuity during the ongoing shortage. The strategies have included attempts to procure additional stock, repackage existing stock for use in larger numbers of patients, use noncontrast CT or alternative imaging modalities in place of contrast-enhanced CT, and collaborate with specialties outside of radiology to participate in conservation efforts. In addition, individual CT protocols underwent tailored modifications to use dual-energy technique and/or lower tube voltages, to allow lower contrast media doses with maintained visualization of tissue enhancement. The experiences during this period provide insights to facilitate long-term reductions in contrast media doses and ongoing CT protocol optimization after supplies return to normal levels. Critical throughout the efforts to mitigate the impact of the shortage have been system-level action, operational flexibility, and close communication by the health system's radiologists, technologists, physicists, pharmacists, and ordering providers.
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- 2022
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27. Multiparametric imaging of breast cancer: An update of current applications
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Masako Kataoka, Mami Iima, Kanae Kawai Miyake, and Yoshiaki Matsumoto
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Diffusion Magnetic Resonance Imaging ,Radiological and Ultrasound Technology ,Positron-Emission Tomography ,Humans ,Contrast Media ,Female ,Breast Neoplasms ,Radiology, Nuclear Medicine and imaging ,Breast ,General Medicine - Abstract
Imaging plays an indispensable role in the diagnosis and treatment of breast cancer. Several new imaging tools are currently being developed for clinical use to improve diagnostic performance and tumor response evaluation. Abbreviated magnetic resonance imaging (MRI) allows shortening scanning time without penalizing diagnostic performances. Ultrafast dynamic contrast-enhanced MRI is a new approach that provides kinetic information and helps identify breast lesions developed in breast with marked background parenchymal enhancement. Intravoxel incoherent motion and kurtosis are parameters of diffusion-weighted imaging (DWI) that bring useful information in breast cancer. High-resolution DWI, allows morphological assessment of lesions without using a contrast agent. High-resolution breast positron emission tomography provides detailed metabolic information on small breast cancer. Photoacoustic imaging utilizes hemoglobin as an intrinsic contrast agent and depicts fine -branching structure of the tumor vessels related to cancer. It is important that experts in breast imaging understand the advantages and limitations of these new techniques in order to offer optimal imaging to each patient.
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- 2022
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28. Association between right ventricular longitudinal strain and cardiovascular events in patients with cardiac sarcoidosis
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Noor K, Albakaa, Kimi, Sato, Noriko, Iida, Masayoshi, Yamamoto, Tomoko, Machino-Ohtsuka, Tomoko, Ishizu, and Masaki, Ieda
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Myocarditis ,Sarcoidosis ,Heart Ventricles ,Ventricular Dysfunction, Right ,Ventricular Function, Right ,Humans ,Contrast Media ,Gadolinium ,Prognosis ,Cardiology and Cardiovascular Medicine - Abstract
While right ventricular (RV) involvement is commonly observed in patients with cardiac sarcoidosis (CS), the utility of strain imaging to detect RV involvement is unclear. We aimed to investigate the association between RV free wall longitudinal strain (RVFWLS) and cardiovascular events in patients with CS.We studied 51 patients with CS who were diagnosed between 2012 and 2020. All patients underwent comprehensive echocardiographic evaluation, and RVFWLS was assessed using 2-dimensional speckle tracking echocardiography. The primary outcome was major adverse cardiovascular events (MACEs).During a median follow-up duration of 548 days, 11 patients exhibited MACEs. In the univariable Cox proportional hazards model, the baseline RVFWLS was associated with MACEs (hazard ratio: 1.29, p = 0.008). The addition of RVFWLS to the conventional echocardiographic parameters exhibited a significant incremental value associated with MACEs. Patients with reduced RVFWLS showed a higher prevalence of late gadolinium enhancement on cardiac magnetic resonance imaging in RV wall (p = 0.02) and trends toward higher prevalence of fluorodeoxyglucose uptake in RV (p = 0.06). A serial echocardiographic evaluation revealed that patients with events showed a worsening in RVFWLS, while others showed a trend toward improvement.Impaired RVFWLS at baseline was associated with MACEs in patients with CS. RVFWLS could be an important surrogate of disease activity and prognosis by detecting active RV involvement in CS.
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- 2022
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29. Microvascular imaging: new Doppler technology for assessing focal liver lesions. Is it useful?
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A, Wilson and A K P, Lim
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Diagnosis, Differential ,Technology ,Liver ,Liver Neoplasms ,Humans ,Contrast Media ,Ultrasonography, Doppler ,Radiology, Nuclear Medicine and imaging ,General Medicine ,Sensitivity and Specificity ,Ultrasonography - Abstract
Microvascular imaging (MVI) is an advanced Doppler ultrasound technique, permitting detailed evaluation of microvessel architecture without the need for contrast agents. The clinical applications of the technology are broad, with a growing body of evidence suggesting a potential role for MVI in the characterisation of benign and malignant focal liver lesions (FLLs). This review discusses the current evidence regarding the use of MVI in the assessment of FLLs, with a proposed algorithmic approach to radiological work-up of FLLs based on MVI features. Ongoing research and future directions in the field are highlighted.
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- 2022
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30. Dynamic Contrast-Enhanced Ultrasound Modeling of an Analog to Pseudo-Diffusivity in Intravoxel Incoherent Motion Magnetic Resonance Imaging
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Dimitre Hristov, Lauri Mustonen, Rie von Eyben, Sebastian Gotschel, Michael Minion, and Ahmed El Kaffas
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Mice ,Motion ,Diffusion Magnetic Resonance Imaging ,Radiological and Ultrasound Technology ,Animals ,Contrast Media ,Electrical and Electronic Engineering ,Magnetic Resonance Imaging ,Software ,Ultrasonography ,Computer Science Applications - Abstract
Tumor perfusion and vascular properties are important determinants of cancer response to therapy and thus various approaches for imaging perfusion are being explored. In particular, Intravoxel Incoherent Motion (IVIM) MRI has been actively researched as an alternative to Dynamic-Contrast-Enhanced (DCE) CT and DCE-MRI as it offers non-ionizing, non-contrast-based perfusion imaging. However, for repetitive treatment assessment in a short time period, high cost, limited access, and inability to scan at the bedside remain disadvantages of IVIM MRI. We propose an analysis framework that may enable 3D DCE Ultrasound (DCE-US) - low cost, bedside imaging with excellent safety record - as an alternative modality to IVIM MRI for the generation of DCE-US based pseudo-diffusivity maps in acoustically accessible anatomy and tumors. Modelling intravascular contrast propagation as a convective-diffusive process, we reconstruct parametric maps of pseudo-diffusivity by solving a large-scale fully coupled inverse problem without any assumptions regarding local constancy of the reconstructed parameters. In a mouse tumor model, we demonstrate that the 3D DCE-US pseudo-diffusivity is repeatable, sensitive to treatment with an antiangiogenic agent, and moderately correlated to histological measures of perfusion and angiogenesis.
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- 2022
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31. Clear speech in Tashlhiyt Berber: The perception of typologically uncommon word-initial contrasts by native and naive listeners
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Georgia Zellou, Mohamed Lahrouchi, and Karim Bensoukas
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Acoustics and Ultrasonics ,Arts and Humanities (miscellaneous) ,Phonetics ,Speech Perception ,Speech ,Contrast Media ,Language - Abstract
Tashlhiyt Berber is known for having typologically unusual word-initial phonological contrasts, specifically, word-initial singleton-geminate minimal pairs (e.g., sin vs ssin) and sequences of consonants that violate the sonority sequencing principle (e.g., non-rising sonority sequences: fsin). The current study investigates the role of a listener-oriented speaking style on the perceptual enhancement of these rarer phonological contrasts. It examines the perception of word-initial singleton, geminate, and complex onsets in Tashlhiyt Berber across clear and casual speaking styles by native and naive listeners. While clear speech boosts the discriminability of pairs containing singleton-initial words for both listener groups, only native listeners performed better in discriminating between initial singleton-geminate contrasts in clear speech. Clear speech did not improve perception for lexical contrasts containing a non-rising-sonority consonant cluster for either listener group. These results are discussed in terms of how clear speech can inform phonological typology and the role of phonetic enhancement in language-universal vs language-specific speech perception.
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- 2022
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32. Application of Contrast-enhanced Ultrasound and Bosniak Classification to the Diagnosis of Cystic Renal Masses
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Mei-Feng, Huang, Zhi, Zhang, Qing-Qing, Xia, Xi-Ling, Zhou, Xin-Chun, Yuan, and Zhi-Yu, Zhou
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Humans ,Contrast Media ,Radiology, Nuclear Medicine and imaging ,Kidney ,Sensitivity and Specificity ,Retrospective Studies ,Ultrasonography - Abstract
Background: The Bosniak classification system based on contrast-enhanced computed tomography (CECT) is commonly used for the differential diagnosis of cystic renal masses. Contrastenhanced ultrasound (CEUS) is a relatively novel technique, which has gradually played an important role in the diagnosis of cystic renal cell carcinoma (CRCC) due to its safety and lowest price. Objective: The aim of the study is to investigate the application value of CEUS and Bosniak classification into the diagnosis of cystic renal masses. Method: 32 cystic masses from January 2018 to December 2019 were selected. The images of conventional ultrasound (US), CEUS and CECT from subjects confirmed by surgical pathology were retrospectively analyzed. The Bosniak classification system of cystic renal masses was implemented using CEUS and CECT, and the diagnostic ability was compared. Results: For the 32 cystic masses, postoperative pathology confirmed 11 cases of multilocular CRCC, 15 cases of clear cell carcinoma with hemorrhage, necrosis and cystic degeneration, 5 cases of renal cysts, and 1 case of renal tuberculosis. The Bosniak classification based on CEUS was higher than that based on CECT, and the difference was statistically significant (P = .024). The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of CEUS were comparable to CECT. There was no significant difference observed in the diagnosis of CRCC (P >.05). Conclusion: CEUS combined with Bosniak classification greatly improves the diagnosis of CRCC. CEUS shows a comparable diagnostic ability to CECT. In daily clinical routine, patients who require multiple examinations and present contraindications for CECT can particularly benefit from CEUS.
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- 2022
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33. A Multicenter Randomized Controlled Study of Contrast-enhanced US versus US-guided Biopsy of Focal Liver Lesions
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Wei Wu, Xiang Jing, Gai-qin Xue, Xiao-lin Zhu, Jing Wang, Rui-qing Du, Bin Lv, Ke-feng Wang, Ji-Ping Yan, Zhong-yi Zhang, Man-di Li, Yuko Kono, and Kun Yan
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Adult ,Male ,Carcinoma, Hepatocellular ,Biopsy ,Liver Neoplasms ,Contrast Media ,Middle Aged ,Sensitivity and Specificity ,Humans ,Female ,Radiology, Nuclear Medicine and imaging ,Prospective Studies ,Retrospective Studies ,Ultrasonography - Abstract
Background Retrospective or single-center prospective studies with relatively small samples have shown that contrast-enhanced US (CEUS) can improve the diagnostic accuracy of percutaneous biopsy, but larger prospective studies are lacking. Purpose To assess the diagnostic performance of CEUS-guided biopsy (CEUS-GB) of focal liver lesions (FLLs) compared with US-guided biopsy (US-GB) in a prospective multicenter study. Materials and Methods In this randomized controlled study conducted in nine hospitals in China between March 2016 and August 2019, adult participants with FLLs detected with US, CT, or MRI and planned for percutaneous biopsy were randomly assigned to undergo either US-GB or CEUS-GB. Lesions diagnosed as malignant at histopathologic analysis were considered true-positive findings. Benign or indeterminate lesions required further confirmation with either repeat biopsy or clinical follow-up at 6 months or later. The primary endpoint was the diagnostic accuracy rate, and comparison between groups was made using the χ
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- 2022
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34. Brain Glucose Activated MRI Contrast Agent for Early Diagnosis of Alzheimer’s Disease
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Jiamin Liu, Chuyao Chen, Huiting Chen, Cong Huang, Qingfan Ren, Mingyan Sun, Jia Tao, Bingquan Lin, and Peng Zhao
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Glucose Oxidase ,Glucose ,Early Diagnosis ,Manganese Compounds ,Alzheimer Disease ,Zeolites ,Humans ,Contrast Media ,Brain ,Oxides ,Magnetic Resonance Imaging ,Analytical Chemistry - Abstract
Brain glucose is an important biomarker of Alzheimer's disease (AD) and has a high specificity especially for early AD. Activatable magnetic resonance imaging (MRI) contrast agents (CAs) serve as a robust technology in the early diagnosis of many diseases; however, there is a lack of glucose-specific MRI CAs. To address this issue, in this work, we synthesized a novel MRI CA (ZIF-8/GOx@MnO
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- 2022
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35. Avoiding Contrast-Enhanced Imaging to Prevent Contrast-Induced Acute Kidney Injury
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Clement D. Lee, Jeremiah Hinson, and Matthew S. Davenport
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Diagnostic Imaging ,Risk Factors ,Humans ,Contrast Media ,General Medicine ,Acute Kidney Injury ,Kidney - Published
- 2022
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36. Imaging or Adrenal Vein Sampling Approach in Primary Aldosteronism? A Patient-Based Approach
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Irene Tizianel, Chiara Sabbadin, Caterina Mian, Carla Scaroni, and Filippo Ceccato
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Diagnostic Imaging ,Psychotherapy ,surgery ,primary aldosteronism ,adrenal vein sampling ,Hyperaldosteronism ,Hypersensitivity ,Humans ,Contrast Media ,Radiology, Nuclear Medicine and imaging - Abstract
Primary aldosteronism (PA) is the most frequent cause of secondary hypertension, associated with an increased risk of cardiovascular and cerebral disease, compared to essential hypertension. Therefore, it is mandatory to promptly recognize the disease and offer to the patient the correct diagnostic–therapeutic process in order to reduce new-onset cardiovascular events. It is fundamental to define subtype classification (unilateral or bilateral disease), in order to provide the best treatment (surgery for unilateral and medical treatment for bilateral disease). Here, we report five clinical cases of different subtypes of PA (patients with monolateral or bilateral PA, nondiagnostic AVS, allergy to iodinated contrast, and patients not suitable for surgery), with particular attention to the diagnostic–therapeutic process and the different approaches tailored to a single case. Since PA is a spectrum of various diseases, it needs a personalized diagnostic–therapeutic process, customized for the individual patient, depending on previous medical history, suitability for the surgery and patient’s preferences.
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- 2022
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37. Iron‐based coupling media for MRI‐guided ultrasound surgery
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Steven P, Allen, Austin, Fergusson, Connor, Edsall, Sheng, Chen, David, Moore, Eli, Vlaisavljevich, Richey M, Davis, and Craig H, Meyer
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Phantoms, Imaging ,Iron ,Temperature ,Humans ,Water ,Contrast Media ,General Medicine ,Magnetic Resonance Imaging - Abstract
In this study, we examine the effects of a recently developed, iron-based coupling medium (IBCM) on guidance magnetic resonance (MR) scans during transcranial, magnetic-resonance-guided, focused ultrasound surgery (tMRgFUS) procedures. More specifically, this study tests the hypotheses that the use of the IBCM will (a) not adversely affect image quality, (b) remove aliasing from small field-of-view scans, and (c) decouple image quality from the motion state of the coupling fluid.An IBCM, whose chemical synthesis and characterization are reported elsewhere, was used as a coupling medium during tMRgFUS procedures on gel phantoms. Guidance magnetization-prepared rapid-gradient-echo (MP-RAGE), TSE, and GRE scans were acquired with fields of view of 28 and 18 cm. Experiments were repeated with the IBCM in several distinct flow states. GRE scans were used to estimate temperature time courses as a gel target was insonated. IBCM performance was measured by computing (i) the root mean square difference (RMSD) of TSE and GRE pixel values acquired using water and the IBCM, relative to the use of water; (ii) through-time temperature uncertainty for GRE scans; and (iii) Bland-Altman analysis of the temperature time courses. Finally, guidance TSE and GRE scans of a human volunteer were acquired during a separate sham tMRgFUS procedure. As a control, all experiments were repeated using a water coupling medium.Use of the IBCM reduced RMSD in TSE scans by a factor of 4 or more for all fields of view and nonstationary motion states, but did not reduce RMSD estimates in MP-RAGE scans. With the coupling media in a stationary state, the IBCM altered estimates of temperature uncertainty relative to the use of water by less than 0.2°C. However, with a high flow state, the IBCM reduced temperature uncertainties by the statistically significant amounts (at the 0.01 level) of 0.5°C (28 cm field of view) and 5°C (18 cm field of view). Bland-Altman analyses found a 0.1°C ± 0.5°C difference between temperature estimates acquired using water and the IBCM as coupling media. Finally, scans of a human volunteer using the IBCM indicate more conspicuous grey/white matter contrast, a reduction in aliasing, and a less than 0.2°C change in temperature uncertainty.The use of an IBCM during tMRgFUS procedures does not adversely affect image quality for TSE and GRE scans, can decouple image quality from the motion state of the coupling fluid, and can remove aliasing from scans where the field of view is set to be much smaller than the spatial extent of the coupling fluid.
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- 2022
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38. Unerwünschte kardiale Nebenwirkungen einer COVID-19-Impfung: Befunde in der kardialen MRT
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Dmitrij, Kravchenko and Julian Alexander, Luetkens
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Male ,COVID-19 Vaccines ,Humans ,Contrast Media ,COVID-19 ,Gadolinium ,Pandemics ,Magnetic Resonance Imaging - Abstract
The rapid development of COVID-19 vaccines in the wake of the COVID-19 pandemic has led to an equally expediently deployed vaccination campaign with more than 12 billion vaccinations administered worldwide. Reports of vaccine-associated adverse reactions (VAARs) have ranged from headaches and pain at the injection site to potentially life-threatening events such as cerebral venous sinus thrombosis. The heart has also not been spared of VAARs, as vaccine-associated myocardial infarction and more commonly, albeit still rare, myocarditis and perimyocarditis have been reported in predominantly young male recipients.Cardiac magnetic resonance imaging findings of vaccine-associated myocarditis such as prolonged T1 and T2 relaxation times, increased T2 signal intensity ratio, and subepicardial late gadolinium enhancement have been demonstrated to be similar to those in virus-induced myocarditis, enabling the use of the modified 2018 Lake Louise Criteria for diagnostic purposes to confirm vaccination-associated myocardial inflammation. Other reported cardiac findings such as cardiomyopathies and arrhythmias were confined to case reports. The incidence of myocardial infarction was not noted to be higher than in the overall population.The overall preliminary prognosis of vaccine- associated myocarditis seems to be good as suggested by initial reports, but long-term follow-up is needed to sufficiently assess possible sequelae and consequences.HINTERGRUND: Die rasche Entwicklung von COVID-19-Impfstoffen im Rahmen der COVID-19-Pandemie hat zu einer zügigen Impfkampagne geführt, im Rahmen derer mehr als 12 Mrd. Impfungen weltweit durchgeführt wurden. Die Berichte über Impfnebenwirkungen („vaccine-associated adverse reactions“, VAAR) reichen dabei von Kopfschmerzen und Schmerzen an der Injektionsstelle bis hin zu potenziell lebensbedrohlichen Ereignissen wie zerebrale Venen- und Sinusthrombosen. Auch kardiale Impfnebenwirkungen wurden beschrieben. Solche kardialen VAAR scheinen überwiegend junge Männer zu betreffen. Obwohl diese kardialen Impfnebenwirkungen sehr selten sind, gibt es einige Berichte über Myokarditiden und Perimyokarditiden nach Impfung.Die Magnetresonanztomographie(MRT)-Befunde der impfassoziierten Myokarditis, wie verlängerte T1- und T2-Relaxationszeiten, fokale T2-Signalerhöhungen und ein subepikardiales Late-Gadolinium-Enhancement ähneln nachweislich denen der virusinduzierten Myokarditis, sodass die modifizierten Lake-Louise-Kriterien 2018 für diagnostische Zwecke zum Nachweis einer impfassoziierten myokardialen Inflammation verwendet werden können. Sonstige kardiale Befunde wie Kardiomyopathien und Arrhythmien beschränken sich aktuell auf Fallberichte. Berichte über Myokardinfarkte nach Impfung sind ebenfalls sehr selten. Die Inzidenz von Myokardinfarkten ist nicht höher als in der Gesamtbevölkerung.Die vorläufige Gesamtprognose der impfstoffassoziierten Myokarditis scheint den ersten Berichten zufolge gut zu sein, doch sind langfristige Nachuntersuchungen erforderlich, um mögliche Folgeerkrankungen und Konsequenzen ausreichend bewerten zu können.
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- 2022
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39. Coordination-Driven Self-Assembly of Iron Oxide Nanoparticles for Tumor Microenvironment-Responsive Magnetic Resonance Imaging
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Jinhong Hou, Hongqian Liu, Qian Ma, Suying Xu, and Leyu Wang
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Neoplasms ,Tumor Microenvironment ,Humans ,Contrast Media ,Nanoparticles ,Magnetic Iron Oxide Nanoparticles ,Magnetic Resonance Imaging ,Analytical Chemistry - Abstract
Accurate diagnosis of diseases located in deep tissues is always challenging. The "always-on" probe often leads to false-positive signals due to nonspecific interaction of nanoprobes. Thus, stimuli-responsive nanoprobes are highly desirable, which, however, require complicated surface modification so as to achieve trigger-induced signal changes. Here pH-triggered switchable magnetic resonance imaging (MRI) nanoprobes were constructed by coordination-driven self-assembly of monodispersed iron oxide nanoparticles (MIONPs) with simple amino acid derivatives, which displayed typical
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- 2022
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40. The Influence of Nanobubble Size and Stability on Ultrasound Enhanced Drug Delivery
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Damien V. B. Batchelor, Fern J. Armistead, Nicola Ingram, Sally A. Peyman, James R. McLaughlan, P. Louise Coletta, and Stephen D. Evans
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Microbubbles ,Drug Delivery Systems ,Liposomes ,Electrochemistry ,Contrast Media ,General Materials Science ,Surfaces and Interfaces ,Condensed Matter Physics ,Lipids ,Spectroscopy ,Ultrasonography - Abstract
Lipid-shelled nanobubbles (NBs) are emerging as potential dual diagnostic and therapeutic agents. Similar to their micron-scale counterparts, microbubbles (1-10 μm), they can act as ultrasound contrast agents as well as locally enhance therapeutic uptake. Recently, it has been shown that the reduced size of NBs (1 μm) promotes increased uptake and accumulation in tumor interstitial space, which can enhance their diagnostic and therapeutic performance. However, accurate characterization of NB size and concentration is challenging and may limit their translation into clinical use. Their submicron nature limits accuracy of conventional microscopy techniques, while common light scattering techniques fail to distinguish between subpopulations present in NB samples (i.e., bubbles and liposomes). Due to the difficulty in the characterization of NBs, relatively little is known about the influence of size on their therapeutic performance. In this study, we describe a novel method of using a commercially available nanoparticle tracking analysis system, to distinguish between NBs and liposomes based on their differing optical properties. We used this technique to characterize three NB populations of varying size, isolated via centrifugation, and subsequently used this to assess their potential for enhancing localized delivery. Confocal fluorescence microscopy and image analysis were used to quantify the ultrasound enhanced uptake of fluorescent dextran into live colorectal cancer cells. Our results showed that the amount of localized uptake did not follow the expected trends, in which larger NB populations out-perform smaller NBs, at matched concentration. To understand this observed behavior, the stability of each NB population was assessed. It was found that dilution of the NB samples from their stock concentration influences their stability, and it is hypothesized that both the total free lipid and interbubble distance play a role in NB lifetime, in agreement with previously proposed theories and models.
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- 2022
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41. Simultaneous depiction of clot and MRA using 1 min phase contrast angiography in acute ischemic patients
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Daisuke, Oura, Masayuki, Gekka, Yutaka, Morishima, Yoshimasa, Niiya, Riku, Ihara, Thubasa, Ebina, and Hiroyuki, Sugimori
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Ischemia ,Biomedical Engineering ,Biophysics ,Angiography, Digital Subtraction ,Contrast Media ,Humans ,Thrombosis ,Radiology, Nuclear Medicine and imaging ,Magnetic Resonance Imaging ,Magnetic Resonance Angiography ,Ischemic Stroke - Abstract
[Background and Purpose] Clot location and range predict clinical outcomes for acute ischemic stroke (AIS). We developed a new technique for visualizing occlusion clots, namely, the DEpicting blood clot and MRA using Phase contrast angiography with Image Calculation for Thrombectomy (DEPICT) method. The purpose of this study was to assess the clinical usefulness of DEPICT. [Methods] We used DEPICT in 36 AIS patients to obtain MRA and black blood images with 1-min phase contrast angiography (PCA). We created the black blood images by subtracting the MRA from the T1WI using the source image of PCA. We evaluated the motion artifact, detectability of clot, and precision in location and range compared these to that of susceptibility vessel sign in T2*WI and measured contrast ration (CR) of clot between the cistern and brain tissue. Motion artifact was visually evaluated using a 3-point scale. Detectability and precision of the location and range of occlusion clots were assessed by comparison with findings from digital subtraction angiography (DSA). Gwet's AC
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- 2022
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42. Natural History of Myocardial Injury After COVID-19 Vaccine–Associated Myocarditis
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Muhammad Mustafa Alhussein, Mohamad Rabbani, Bradley Sarak, Steven Dykstra, Dina Labib, Jacqueline Flewitt, Carmen P. Lydell, Andrew G. Howarth, Neil Filipchuck, Angela Kealey, Jillian Colbert, Nita Guron, Louis Kolman, Naeem Merchant, Murad Bandali, Mike Bristow, and James A. White
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Male ,Adult ,COVID-19 Vaccines ,Adolescent ,Myocardium ,Contrast Media ,COVID-19 ,Magnetic Resonance Imaging, Cine ,Gadolinium ,Convalescence ,Stroke Volume ,Fibrosis ,Ventricular Function, Left ,Young Adult ,Myocarditis ,Heart Injuries ,Predictive Value of Tests ,Humans ,Female ,RNA, Messenger ,Cardiology and Cardiovascular Medicine - Abstract
Acute myocarditis is a rare complication of mRNA-based COVID-19 vaccination. Little is known about the natural history of this complication.Baseline and convalescent (≥ 90 days) cardiac magnetic resonance (CMR) imaging assessments were performed in 20 consecutive patients meeting Updated Lake Louise Criteria for acute myocarditis within 10 days of mRNA-based vaccination. CMR-based changes in left ventricular volumes, mass, ejection fraction (LVEF), markers of tissue inflammation (native T1 and T2 mapping), and fibrosis (late gadolinium enhancement [LGE] and extracellular volume [ECV]) were assessed between baseline and convalescence. Cardiac symptoms and clinical outcomes were captured.Median age was 23.1 years (range 18-39 years), and 17 (85%) were male. Convalescent evaluations were performed at a median (IQR) 3.7 (3.3-6.2) months. The LVEF showed a mean 3% absolute improvement, accompanied by a 7% reduction in LV end-diastolic volume and 5% reduction in LV mass (all P0.015). Global LGE burden was reduced by 66% (P0.001). Absolute reductions in global T2, native T1, and ECV of 2.1 ms, 58 ms, and 2.9%, repectively, were documented (all P ≤ 0.001). Of 5 patients demonstrating LVEF ≤ 50% at baseline, all recovered to above this threshold in convalescence. A total of 18 (90%) patients showed persistence of abnormal LGE although mean fibrosis burden was5% of LV mass in 85% of cases. No patient experienced major clinical outcomes.COVID-19 mRNA vaccine-associated myocarditis showed rapid improvements in CMR-based markers of edema, contractile function, and global LGE burden beyond 3 months of recovery in this young patient cohort. However, regional fibrosis following edema resolution was commonly observed, justifying need for ongoing surveillance.
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- 2022
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43. Power Modulation Echocardiography to Detect and Quantify Myocardial Scar
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Alexandros Papachristidis, Konstantinos C. Theodoropoulos, Apostolia Marvaki, Sandro Queirós, Jan D’hooge, Giovanni Masoero, Gianpiero Pagnano, Marilou Huang, Luke Dancy, Daniel Sado, Ajay M. Shah, Francis D. Murgatroyd, and Mark J. Monaghan
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Cicatrix ,Predictive Value of Tests ,Echocardiography ,Myocardium ,Myocardial Infarction ,Humans ,Contrast Media ,Magnetic Resonance Imaging, Cine ,Gadolinium ,Radiology, Nuclear Medicine and imaging ,Prospective Studies ,Cardiology and Cardiovascular Medicine ,Magnetic Resonance Imaging - Abstract
Myocardial scar correlates with clinical outcomes. Traditionally, late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) is used to detect and quantify scar. In this prospective study using LGE CMR as reference, the authors hypothesized that nonlinear ultrasound imaging, namely, power modulation, can detect and quantify myocardial scar in selected patients with previous myocardial infarction. In addition, given the different histopathology between ischemic and nonischemic scar, a further aim was to test the diagnostic performance of this echocardiographic technique in unselected consecutive individuals with ischemic and nonischemic LGE or no LGE on CMR.Seventy-one patients with previous myocardial infarction underwent power modulation echocardiography following CMR imaging (group A). Subsequently, 101 consecutive patients with or without LGE on CMR, including individuals with nonischemic LGE, were scanned using power modulation echocardiography (group B).In group A, echocardiography detected myocardial scar in all 71 patients, with good scar volume agreement with CMR (bias = -1.9 cmsup3/sup; limits of agreement [LOA], -8.0 to 4.2 cmsup3/sup). On a per-segment basis, sensitivity was 82%, specificity 97%, and accuracy 92%. Sensitivity was higher in the inferior and posterior segments and lower in the anterior and lateral walls. In group B, on a per-subject basis, the sensitivity of echocardiography was 62% (91% for ischemic and 30% for nonischemic LGE), with specificity and accuracy of 89% and 72%, respectively. The bias for scar volume between modalities was 5.9 cmsup3/sup, with LOA of 34.6 to 22.9 cmsup3/sup(bias = -1.9 cmsup3/sup[LOA, -11.4 to 7.6 cmsup3/sup] for ischemic LGE, and bias = 18.9 cmsup3/sup[LOA, -67.4 to 29.7.6 cmsup3/sup] for nonischemic LGE).Power modulation echocardiography can detect myocardial scar in both selected and unselected individuals with previous myocardial infarction and has good agreement for scar volume quantification with CMR. In an unselected cohort with nonischemic LGE, sensitivity is low.
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- 2022
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44. Hyperglycemia and intramyocardial hemorrhage in patients with ST-segment elevation myocardial infarction
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Shingo Ota, Tsuyoshi Nishiguchi, Akira Taruya, Takashi Tanimoto, Yasushi Ino, Yosuke Katayama, Yuichi Ozaki, Keisuke Satogami, and Atsushi Tanaka
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Glycated Hemoglobin ,History ,Polymers and Plastics ,Myocardial Infarction ,Contrast Media ,Magnetic Resonance Imaging, Cine ,Gadolinium ,Hemorrhage ,Industrial and Manufacturing Engineering ,Glucose ,Percutaneous Coronary Intervention ,Matrix Metalloproteinase 9 ,Hyperglycemia ,Humans ,ST Elevation Myocardial Infarction ,Business and International Management ,Cardiology and Cardiovascular Medicine - Abstract
Hyperglycemia at admission and intramyocardial hemorrhage (IMH) are associated with poor prognosis in patients with ST-segment elevation myocardial infarction (STEMI). Little is known about the relationship between glucose levels at admission and IMH. The association between matrix metalloproteinase-9 (MMP-9), which plays an important role in the development of IMH, and hyperglycemia is also unknown. This study aimed to investigate the relationship between hyperglycemia at admission and IMH in patients with STEMI.We enrolled 174 patients with first STEMI who underwent primary percutaneous coronary intervention (PCI) and cardiovascular magnetic resonance (CMR) imaging. T2-weighted imaging and late gadolinium enhancement (LGE)-CMR were performed to detect IMH and microvascular obstruction (MVO), respectively. Two patient groups were created: IMH group and non-IMH group. MMP-9 levels were measured in the culprit coronary arteries of 13 patients.Glucose level at admission and the value of glycosylated hemoglobin were higher in the IMH group than in the non-IMH group [IMH group vs. non-IMH group; 208.5 (157.8-300.5) mg/dL vs. 157.0 (128.8-204.3) mg/dL, p 0.001, and 6.2 (5.7-7.5) % vs. 5.8 (5.4-6.6) %, p = 0.030, respectively]. A multivariable logistic regression analysis revealed that only admission glucose level was an independent predictor of IMH (OR: 1.012; 95 % CI: 1.005-1.020, p = 0.001). The MMP-9 levels in patients with IMH were higher than those in patients without IMH [256.0 (161.0-396.0) ng/mL vs. 73.5 (49.5-131.0) ng/mL, p = 0.040]. There was a moderate positive correlation between glucose levels at admission and MMP-9 levels (r = 0.600, p = 0.030).Hyperglycemia at admission is associated with the occurrence of IMH in patients with STEMI.
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- 2022
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45. Liver imaging reporting and data system (LI-RADS) v2018: Reliability and agreement for assessing hepatocellular carcinoma locoregional treatment response
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Ahmed S, Abdelrahman, Mena E Y, Ekladious, Ethar M, Badran, and Sherihan S, Madkour
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Male ,Adult ,Carcinoma, Hepatocellular ,Radiological and Ultrasound Technology ,Liver Neoplasms ,Reproducibility of Results ,Contrast Media ,General Medicine ,Middle Aged ,Sensitivity and Specificity ,Magnetic Resonance Imaging ,Young Adult ,Humans ,Female ,Radiology, Nuclear Medicine and imaging ,Chemoembolization, Therapeutic ,Aged ,Retrospective Studies - Abstract
The purpose of this study was to determine the reliability and interobserver agreement of the liver imaging reporting and data system (LI-RADS) treatment response algorithm (LR-TR) v2018 using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and the added value of diffusion-weighted imaging (DWI).A total of 54 patients who underwent DCE-MRI and DWI after locoregional treatment of 81 hepatocellular carcinoma (HCC) lesions from September 2020 to July 2021 were included. There were 47 men and 7 women, with a mean age of 63.9 ± 9.2 (SD) years (age range: 23-77 years). Locoregional treatments included transarterial chemoembolization (TACE) (53/81; 65.4%), radiofrequency ablation (RFA) (25/81; 30.9%) and microwave ablation (MWA) (3/81; 3.7%). Two independent radiologists retrospectively evaluated DCE-MRI examinations obtained after locoregional treatment using LR-TR, and then three months later both radiologists reevaluated DCE-MRI examinations with DWI. Interobserver agreement was assessed using intraclass correlation coefficient (ICC) and Kappa test. Diagnostic performances were evaluated in term of sensitivity, specificity, and area under ROC curve (AUC) using a composite standard of reference that included results of histopathological examinations and follow-up findings.Using DCE-MRI alone, observer 1 had 83.9% sensitivity (26/31; 95% confidence interval [CI]: 66-95%), 88% specificity (44/50; 95% CI: 76-95%) and 86.4% accuracy (70/81; 95%CI: 77-93%), and observer 2 had 71% sensitivity (22/31; 95% CI: 52-86%), 92% specificity (46/50; 95% CI: 81-98%) and 83.9% accuracy (68/81; 95% CI: 74-91%). For the diagnosis of viable tumors using DCE-MRI with DWI, observer 1 and observer 2 had 87.1% (27/31; 95% CI: 70-96%) and 74.2% (23/31; 95% CI: 55-88%) sensitivity, respectively. The diagnostic performance of DCE-MRI with DWI yielded an AUC (0.875; 95% CI: 0.789-0.962) not different from that of DCE-MRI without DWI (0.859; 95% CI: 0.768-0.951) (P = 0.317). Interobserver agreement for arterial phase hyperenhancement, washout, enhancement similar to pretreatment and DWI findings in all treated HCCs was almost perfect (kappa = 0.815, 0.837, 0.826 and 0.81 respectively). Agreement between observers for LR-TR category was substantial (kappa = 0.795; 95% CI: 0.665-0.924). Interobserver agreement for size of viable HCC was excellent (ICC = 0.938; 95% CI: 0.904-0.960).LR-TR using DCE-MRI alone or DCE-MRI with DWI are both accurate for detecting viable HCC lesions after locoregional treatment, with no differences in diagnostic performance and excellent interobserver agreement.
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- 2022
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46. Prevalence and prognostic impact of mitral annular disjunction in patients with STEMI – A cardiac magnetic resonance study
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Felix Troger, Martin Reindl, Christina Tiller, Ivan Lechner, Magdalena Holzknecht, Priscilla Fink, Paulina Poskaite, Mathias Pamminger, Bernhard Metzler, Sebastian Reinstadler, Gert Klug, and Agnes Mayr
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History ,Magnetic Resonance Spectroscopy ,Polymers and Plastics ,Contrast Media ,Magnetic Resonance Imaging, Cine ,Gadolinium ,Prognosis ,Magnetic Resonance Imaging ,Industrial and Manufacturing Engineering ,Percutaneous Coronary Intervention ,Prevalence ,Humans ,ST Elevation Myocardial Infarction ,Business and International Management ,Cardiology and Cardiovascular Medicine - Abstract
Mitral annular disjunction (MAD) represents the detachment of the mitral leaflet hinge-point from the ventricular myocardium. Its role in patients with ST-segment-elevation myocardial infarction (STEMI) is unknown. This study aims to investigate the prevalence of MAD by cardiac magnetic resonance imaging (CMR) in STEMI-patients and its association with serious adverse events.STEMI-patients (n = 621) underwent CMR 4 days [interquartile range (IQR) 2-5] after percutaneous coronary intervention. Presence and longitudinal extent of MAD were obtained in long-axis cine-images, infarct characteristics in late gadolinium enhancement-images. During a median follow-up time of 366 days (IQR 136-454), patients were observed for the occurrence of major adverse cardiac events (MACE), comprising death, myocardial reinfarction, and congestive heart failure.Overall, 307 patients (49 %) had MAD. Longitudinal MAD-distance was 4.6 ± 1.7 mm and the P3-segment was affected most frequently (n = 262, 85 % of MAD-patients). MAD-patients had a significantly smaller infarct size, lower prevalence of microvascular obstruction, and intramyocardial hemorrhage as well as a higher ejection fraction (all p 0.03). During follow-up period, MACE occurred in 52 patients (8 %) and did not show significant difference between patients with and without MAD (7 % vs. 9 %, p = 0.424). Cardiovascular death occurred significantly more often in patients without MAD (n = 10, 3.2 % vs. n = 2, 0.7 %, p = 0.021).MAD is a rather common finding in patients presenting with STEMI. Patients with MAD had less severe infarct characteristics, however, they were not more commonly affected by MACE. Further confirmation and longer follow-up intervals are necessary to define the exact role of MAD in STEMI patients.
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- 2022
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47. Machine-Learning Score Using Stress CMR for Death Prediction in Patients With Suspected or Known CAD
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Théo Pezel, Francesca Sanguineti, Philippe Garot, Thierry Unterseeh, Stéphane Champagne, Solenn Toupin, Stéphane Morisset, Thomas Hovasse, Alyssa Faradji, Tania Ah-Sing, Martin Nicol, Lounis Hamzi, Jean Guillaume Dillinger, Patrick Henry, Valérie Bousson, and Jérôme Garot
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Male ,Magnetic Resonance Spectroscopy ,Contrast Media ,Magnetic Resonance Imaging, Cine ,Gadolinium ,Coronary Artery Disease ,Middle Aged ,Prognosis ,Risk Assessment ,Machine Learning ,Predictive Value of Tests ,Risk Factors ,Humans ,Female ,Radiology, Nuclear Medicine and imaging ,Cardiology and Cardiovascular Medicine ,Aged ,Retrospective Studies - Abstract
In patients with suspected or known coronary artery disease, traditional prognostic risk assessment is based on a limited selection of clinical and imaging findings. Machine learning (ML) methods can take into account a greater number and complexity of variables.This study sought to investigate the feasibility and accuracy of ML using stress cardiac magnetic resonance (CMR) and clinical data to predict 10-year all-cause mortality in patients with suspected or known coronary artery disease, and compared its performance with existing clinical or CMR scores.Between 2008 and 2018, a retrospective cohort study with a median follow-up of 6.0 (IQR: 5.0-8.0) years included all consecutive patients referred for stress CMR. Twenty-three clinical and 11 stress CMR parameters were evaluated. ML involved automated feature selection by random survival forest, model building with a multiple fractional polynomial algorithm, and 5 repetitions of 10-fold stratified cross-validation. The primary outcome was all-cause death based on the electronic National Death Registry. The external validation cohort of the ML score was performed in another center.Of 31,752 consecutive patients (mean age: 63.7 ± 12.1 years, and 65.7% male), 2,679 (8.4%) died with 206,453 patient-years of follow-up. The ML score (ranging from 0 to 10 points) exhibited a higher area under the curve compared with Clinical and Stress Cardiac Magnetic Resonance score, European Systematic Coronary Risk Estimation score, QRISK3 score, Framingham Risk Score, and stress CMR data alone for prediction of 10-year all-cause mortality (ML score: 0.76 vs Clinical and Stress Cardiac Magnetic Resonance score: 0.68, European Systematic Coronary Risk Estimation score: 0.66, QRISK3 score: 0.64, Framingham Risk Score: 0.63, extent of inducible ischemia: 0.66, extent of late gadolinium enhancement: 0.65; all P 0.001). The ML score also exhibited a good area under the curve in the external cohort (0.75).The ML score including clinical and stress CMR data exhibited a higher prognostic value to predict 10-year death compared with all traditional clinical or CMR scores.
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- 2022
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48. Utility of Sonazoid-Enhanced Ultrasound for the Macroscopic Classification of Hepatocellular Carcinoma: A Meta-analysis
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Zijie, Zheng, Wei, Xie, Jing, Tian, Jiayi, Wu, Baoming, Luo, and Xiaolin, Xu
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Carcinoma, Hepatocellular ,Acoustics and Ultrasonics ,Radiological and Ultrasound Technology ,Iron ,Liver Neoplasms ,Biophysics ,Contrast Media ,Humans ,Oxides ,Radiology, Nuclear Medicine and imaging ,Ferric Compounds ,Magnetic Resonance Imaging ,Sensitivity and Specificity - Abstract
We assessed the diagnostic value of Sonazoid-enhanced ultrasound (SEUS) in determining the macroscopic classification of hepatocellular carcinoma (HCC) because of its strong relevance to the poor prognosis of the non-simple nodular (non-SN) type. The PubMed, EMBASE, Web of Science and Cochrane Library databases were searched for studies investigating patients who underwent surgery for HCC after undergoing SEUS pre-operatively. Five studies involving a total of 334 patients met the inclusion criteria. The summary sensitivity and specificity were 0.74 (95% confidence interval [CI]: 0.63-0.83) and 0.92 (95% CI: 0.82-0.97), respectively. The positive and negative likelihood ratios of SEUS for determining the macroscopic classification of HCC in Kupffer phase were 9.21 (95% CI: 4.02-21.13) and 0.28 (95% CI: 0.19-0.41), respectively. The diagnostic odds ratio of SEUS for determining the macroscopic classification of HCC was 34.2 (95% CI: 11.64-100.51), and the area under the summary receiver operating characteristic curve was 0.87 (95% CI: 0.84-0.90). Subgroup analysis suggested that small HCCs (≤30 mm) and studies including fewer than 70 patients may be associated with a higher diagnostic odds ratio than the corresponding subsets. SEUS had moderate diagnostic value for determining the macroscopic classification of HCC in the Kupffer phase.
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- 2022
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49. Mechanism of Spontaneous Intracerebral Hemorrhage Formation: An Anatomical Specimens-Based Study
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Radosław Rzepliński, Mikołaj Sługocki, Sylwia Tarka, Michał Tomaszewski, Michał Kucewicz, Krzysztof Karczewski, Paweł Krajewski, Jerzy Małachowski, and Bogdan Ciszek
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Advanced and Specialized Nursing ,Hematoma ,Animals ,Contrast Media ,X-Ray Microtomography ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine ,Basal Ganglia ,Cerebral Hemorrhage - Abstract
Background: Despite advances in understanding various risk and prognostic factors, spontaneous intracerebral hemorrhage is connected to very high morbidity and mortality, while the therapy is mainly supportive. Understanding of the pathophysiology of initial hematoma expansion is limited due to insufficient clinical data and lack of a suitable animal model. Methods: We injected 40 anatomic specimens of the basal ganglia with contrast medium, scanned them with a micro-computed tomography scanner and analyzed the results of radiological studies, direct and histological examinations. Results: In 9 cases, micro-computed tomography and histological examinations revealed contrast medium extravasations mimicking intracerebral hematomas. The artificial hematomas spread both proximally and distally along the ruptured perforator and its branches in the perivascular spaces and detached the branches from the adjacent neural tissue leading to destruction of the tissue and secondary extravasations. Moreover, some contrast extravasations skipped to the perivascular spaces of unruptured perforators, created further extravasation sites and aggravated the expansion of the artificial hematoma. There was no subarachnoid extension of any artificial hematoma. Conclusions: We postulate that a forming basal ganglia intracerebral hematoma spreads initially in the perivascular space, detaches the branches from the neural tissue and causes secondary bleeding. It can also skip to the perivascular space of a nearby perforator. The proposed mechanism of hematoma initiation and formation explains extent of damage to the neural tissue, variability of growth in time and space, creation of secondary bleeding sites, and limited usefulness of surgical interventions. The model is reproducible, the extent of the artificial hematoma can be easily controlled, the rupture sites of the perforating arteries can be determined, and preparation of the model does not require specialized, expensive equipment apart from the micro-computed tomography scanner.
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- 2022
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50. Safety profile of Gadoterate meglumine on the renal function of patients with severe kidney disease
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Anugayathri, Jawahar, Jad, El-Bulbul, William, Adams, Cara, Joyce, Joseph, Yacoub, and Ari, Goldberg
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Meglumine ,Organometallic Compounds ,Contrast Media ,Humans ,Gadolinium ,Kidney Diseases ,Radiology, Nuclear Medicine and imaging ,Kidney ,Magnetic Resonance Imaging ,Retrospective Studies - Abstract
Intravenous administration of gadolinium-based contrast agents (GBCA) in patients with impaired renal function has been of concern to primary care physicians due to the potential worsening of renal dysfunction and nephrogenic systemic fibrosis (NSF). Our objective was to compare the potential change in estimated glomerular filtration rate (eGFR) in patients with known severe renal dysfunction (eGFR30 ml/min), following Gadoterate meglumine (GM) administration with patients who do not receive contrast.An IRB-approved retrospective analysis of all patients who underwent MRI examination at our institution, for any indication, between January 2016 and September 2020.pre-MRI eGFR30 ml/min within 24 h of MRI, follow-up eGFR between 48 and 96 h post-MRI, and absence of peritoneal or hemodialysis. The individuals who received GM (492 scans) were identified as cases, and those who did not receive contrast (1101 scans) were identified as controls for our study. Delta-eGFR response was calculated and covariate-adjusted, and propensity score analysis was performed.No significant eGFR decrease was observed in patients who received GM compared to those who did not receive GM in our study. Also, no relationship between comorbidity, severity and contrast selection was observed.The use of Gadolinium contrast in MRI is often of critical importance for determining accurate anatomic relationships, differentiation of benign from malignant lesions, or determination of resolving vs. worsening disease. Though the risk of contrast administration can never be entirely ignored, especially in patients with low eGFR, our study indicates that safe administration of GM can be performed even in patients with severe kidney disease.
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- 2022
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