241,197 results match your criteria contrast agents

Variability of acquisition phase of computed tomography angiography in acute ischemic stroke in a real-world scenario.

Eur Radiol 2021 Jun 15. Epub 2021 Jun 15.

Department of Neuroradiology, Heidelberg University Hospital, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany.

Objectives: The informative value of computed tomography angiography (CTA) depends on the contrast phase in the vessels which may differ depending on the level of local expertise.

Methods: We retrospectively measured vessel contrast density from CTA scans in patients presenting with acute ischemic stroke to a comprehensive stroke center (CSC) or to one of eight primary stroke centers (PSC). CTAs were classified into arterial or venous phases as well as into 1 of 5 phases (early arterial, peak arterial, equilibrium, peak venous, and late venous). Read More

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Comparison of Human Tissue Gadolinium Retention and Elimination between Gadoteridol and Gadobenate.

Radiology 2021 Jun 15:204320. Epub 2021 Jun 15.

From the Department of Radiology (M.K., D.S.H., M.H., N.M., K.M., K.R.M.), Integrated Brain Imaging Center, Department of Radiology (S.R.L.), Department of Neurologic Surgery (K.R.M.), and Magnetic Resonance Research Laboratory (K.R.M.), University of Washington, 1959 NE Pacific St, Box 357115, Seattle, WA 98195; Departments of Radiology (M.K.) and Neurology (K.M.), Toho University Omori Medical Center, Tokyo, Japan; Department of Radiology, Toho University Ohashi Medical Center, Tokyo, Japan (M.H., N.M.); and Department of Pathology, University of Washington School of Medicine, Seattle, Wash (D.A.M., L.F.G.).

Background Linear gadolinium-based contrast agents (GBCAs) are known to be retained at higher levels of gadolinium than macro-cyclic GBCAs. However, very little is known regarding their relative elimination rates and retained fraction of injected gadolinium. Purpose To quantify and compare gadolinium retention and elimination rates in human brain tissue, skin, and bone obtained from cadavers exposed to single-agent administration of either gadoteridol (macrocyclic GBCA) or gadobenate dimeglumine (linear GBCA). Read More

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Effect of Landiolol Hydrochloride on Hemodynamics in a Histamine-Induced Shock Model.

Drugs R D 2021 Jun 14. Epub 2021 Jun 14.

Minase Research Institute of Ono Pharmaceutical, Osaka, Japan.

Background And Objective: Anaphylactic shock is a serious adverse drug reaction that can occur in response to contrast media used during coronary computed tomography angiography. The imaging quality of coronary computed tomography angiography is improved by β-blockers, which decrease heart rate. In this study, we sought to analyze anaphylactic shock treatment in patients receiving short-acting β1-blockers. Read More

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Correction to: Magnetic Nanoparticles as MRI Contrast Agents.

Top Curr Chem (Cham) 2021 Jun 14;379(4):30. Epub 2021 Jun 14.

BIONAND - Centro Andaluz de Nanomedicina y Biotecnología, Junta de Andalucía-Universidad de Málaga, C/Severo Ochoa, 35, 29590, Málaga, Spain.

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Formation and control of disinfection by-products from iodinated contrast media attenuation through sequential treatment processes of ozone-low pressure ultraviolet light followed by chlorination.

Chemosphere 2021 Sep 29;278:130394. Epub 2021 Mar 29.

University of Arizona, Department of Chemical & Environmental Engineering, 1133 E. James E Rogers Way, Harshbarger 108, Tucson, AZ, 85721-0011, USA; Nanyang Technological University, Nanyang Environment & Water Research Institute, Clean Tech One, 1 Cleantech Loop, #06-08, Singapore, 637141, Singapore. Electronic address:

Different groups of disinfection by-products (DBPs) were studied through the degradation of iopamidol by the sequential oxidation process of ozone-low pressure ultraviolet light (O-LPUV) followed by chlorination. This paper investigates the attenuation of iopamidol under this sequential treatment and the effect of chlorine contact time (30 min versus 3 days) to control the formation potential of DBPs: trihalomethanes (THMs), haloacetonitriles (HANs) and haloacetamides (HAMs). Thirty target DBPs among the 9 iodinated-DBPs (I-DBPs), were monitored throughout the sequential treatment. Read More

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September 2021

Fc-binding antibody-recruiting molecules exploit endogenous antibodies for anti-tumor immune responses.

Chem Sci 2020 Feb 25;11(12):3208-3214. Epub 2020 Feb 25.

Department of Applied Chemistry, Graduate School of Engineering, Kyushu University Fukuoka 819-0395 Japan

Redirecting endogenous antibodies in the bloodstream to tumor cells using synthetic molecules is a promising approach to trigger anti-tumor immune responses. However, current molecular designs only enable the use of a small fraction of endogenous antibodies, limiting the therapeutic potential. Here, we report Fc-binding antibody-recruiting molecules (Fc-ARMs) as the first example addressing this issue. Read More

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February 2020

Synthetic biohybrid peptidoglycan oligomers enable pan-bacteria-specific labeling and imaging: and .

Chem Sci 2020 Feb 26;11(12):3171-3179. Epub 2020 Feb 26.

School of Physical and Mathematical Sciences, Nanyang Technological University 21 Nanyang Link Singapore 637371 Singapore

Peptidoglycan is the core component of the bacterial cell wall, which makes it an attractive target for the development of bacterial targeting agents. Intercepting its enzymatic assembly with synthetic substrates allows for labeling and engineering of live bacterial cells. Over the past two decades, small-molecule-based labeling agents, such as antibiotics, d-amino acids or monosaccharides have been developed for probing biological processes in bacteria. Read More

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February 2020

Engineering a 3D collective cancer invasion model with control over collagen fiber alignment.

Biomaterials 2021 Jun 4;275:120922. Epub 2021 Jun 4.

Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States. Electronic address:

Prior to cancer cell invasion, the structure of the extracellular matrix (ECM) surrounding the tumor is remodeled, such that circumferentially oriented matrix fibers become radially aligned. This predisposed radially aligned matrix structure serves as a critical regulator of cancer invasion. However, a biomimetic 3D model recapitulating a tumor's behavioral response to these ECM structures is not yet available. Read More

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Optical Coherence Tomography for Neurovascular Disorders.

Neuroscience 2021 Jun 11. Epub 2021 Jun 11.

University of Massachusetts Medical School, Radiology, University of Massachusetts Medical School, 55 Lake Ave N, Worcester, Massachusetts 01655, United States.

Diagnosis of cerebrovascular disease includes vascular neuroimaging techniques such as CT angiography, MR angiography (with or without use of contrast agents) and catheter digital subtraction angiography. These techniques provide mostly information about the vessel lumen. Vessel wall imaging with MR seeks to characterize cerebrovascular pathology, but with resolution that is often insufficient for small lesions. Read More

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Label-Free Imaging of Lipid Storage Dynamics in Caenorhabditis elegans using Stimulated Raman Scattering Microscopy.

J Vis Exp 2021 May 28(171). Epub 2021 May 28.

Huffington Center on Aging, Baylor College of Medicine; Department of Molecular and Human Genetics, Baylor College of Medicine; Howard Hughes Medical Institute, Baylor College of Medicine.

Lipid metabolism is a fundamental physiological process necessary for cellular and organism health. Dysregulation of lipid metabolism often elicits obesity and many associated diseases including cardiovascular disorders, type II diabetes, and cancer. To advance the current understanding of lipid metabolic regulation, quantitative methods to precisely measure in vivo lipid storage levels in time and space have become increasingly important and useful. Read More

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Bone Marrow Transplantation Procedures in Mice to Study Clonal Hematopoiesis.

J Vis Exp 2021 May 26(171). Epub 2021 May 26.

Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine; Hematovascular Biology Center, Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine;

Clonal hematopoiesis is a prevalent age-associated condition that results from the accumulation of somatic mutations in hematopoietic stem and progenitor cells (HSPCs). Mutations in driver genes, that confer cellular fitness, can lead to the development of expanding HSPC clones that increasingly give rise to progeny leukocytes harboring the somatic mutation. Because clonal hematopoiesis has been associated with heart disease, stroke, and mortality, the development of experimental systems that model these processes is key to understanding the mechanisms that underly this new risk factor. Read More

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Harnessing ultrasound-stimulated phase change contrast agents to improve antibiotic efficacy against methicillin-resistant biofilms.

Biofilm 2021 Dec 11;3:100049. Epub 2021 May 11.

Department of Microbiology and Immunology, University of North Carolina-Chapel Hill, Chapel Hill, NC, 27599, USA.

Bacterial biofilms, often associated with chronic infections, respond poorly to antibiotic therapy and frequently require surgical intervention. Biofilms harbor persister cells, metabolically indolent cells, which are tolerant to most conventional antibiotics. In addition, the biofilm matrix can act as a physical barrier, impeding diffusion of antibiotics. Read More

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December 2021

Monocular Diplopia in Idiopathic Intracranial Hypertension: A Case Report and Literature Review.

Eur J Case Rep Intern Med 2021 4;8(5):002509. Epub 2021 May 4.

Department of Neuroscience, Reproductive Science and Odontostomatology, Federico II University, Naples, Italy.

Background: Diplopia is the double vision of a single object, and can be binocular or monocular. Binocular diplopia is caused by the misalignment of the visual axes, with images falling on the fovea of the fixating eye and on the extra-foveal retina of the non-fixating eye, as a consequence of both neurological (i.e. Read More

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Rationale and Clinical Implications of Fluorescein-Guided Supramarginal Resection in Newly Diagnosed High-Grade Glioma.

Front Oncol 2021 26;11:666734. Epub 2021 May 26.

Gabriele Bartoli Brain Tumor Laboratory, Department of Neurological Surgery and Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY, United States.

Current standard of care for glioblastoma is surgical resection followed by temozolomide chemotherapy and radiation. Recent studies have demonstrated that >95% extent of resection is associated with better outcomes, including prolonged progression-free and overall survival. The diffusely infiltrative pattern of growth in gliomas results in microscopic extension of tumor cells into surrounding brain parenchyma that makes complete resection unattainable. Read More

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The Impact of VEGF Inhibition on Clinical Outcomes in Patients With Advanced Non-Small Cell Lung Cancer Treated With Immunotherapy: A Retrospective Cohort Study.

Front Oncol 2021 28;11:663612. Epub 2021 May 28.

Department of Pulmonary Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.

Background: In recent years, immune checkpoint inhibitors (ICIs) in combination with chemotherapy have increased survival in patients with advanced non-small cell lung cancer (NSCLC). Vascular endothelial growth factor (VEGF), which plays a key role in tumor angiogenesis, is an immunological modulator; therefore, it is expected that anti-VEGF therapy in combination with ICIs enhances the antitumor effect of ICIs. In the present study, we investigated the impact of VEGF inhibition on clinical outcomes of NSCLC patients, including the efficacy of ICI treatment. Read More

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Contrast-Enhanced Ultrasound in the Differential Diagnosis and Risk Stratification of ACR TI-RADS Category 4 and 5 Thyroid Nodules With Non-Hypovascular.

Front Oncol 2021 26;11:662273. Epub 2021 May 26.

Department of Pathology, Lanzhou University Second Hospital, Lanzhou, China.

Objective: This study aims to investigate the value of contrast-enhanced ultrasound (CEUS) in the differential diagnosis and risk stratification of ACR TI-RADS category 4 and 5 thyroid nodules with non-hypovascular.

Methods: From January 2016 to December 2019 in our hospital, 217 ACR TI-RADS category 4 and 5 nodules with non-hypovascular in 210 consecutive patients were included for a derivation cohort. With surgery and/or fine-needle aspiration (FNA) as a reference, conventional ultrasound (US) features and CEUS features were analyzed. Read More

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Diagnostic prospects and preclinical development of optical technologies using gold nanostructure contrast agents to boost endogenous tissue contrast.

Chem Sci 2020 Jul 14;11(33):8671-8685. Epub 2020 Jul 14.

School of Physics and Astronomy, University of Exeter Exeter EX4 4QL UK

Numerous developments in optical biomedical imaging research utilizing gold nanostructures as contrast agents have advanced beyond basic research towards demonstrating potential as diagnostic tools; some of which are translating into clinical applications. Recent advances in optics, lasers and detection instrumentation along with the extensive, yet developing, knowledge-base in tailoring the optical properties of gold nanostructures has significantly improved the prospect of near-infrared (NIR) optical detection technologies. Of particular interest are optical coherence tomography (OCT), photoacoustic imaging (PAI), multispectral optoacoustic tomography (MSOT), Raman spectroscopy (RS) and surface enhanced spatially offset Raman spectroscopy (SESORS), due to their respective advancements. Read More

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Acid-catalyzed proton exchange as a novel approach for relaxivity enhancement in Gd-HPDO3A-like complexes.

Chem Sci 2020 Jul 6;11(30):7829-7835. Epub 2020 Jul 6.

Department of Science and Technological Innovation, Università del Piemonte Orientale Viale T. Michel 11 15121 Alessandria Italy

A current challenge in medical diagnostics is how to obtain high MRI relaxation enhancement using Gd-based contrast agents (CAs) containing the minimum concentration of Gd ions. We report that in GdHPDO3A-like complexes a primary amide group located in close proximity to the coordinated hydroxyl group can provide a strong relaxivity enhancement at slightly acidic pH. A maximum relaxivity of = 9. Read More

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Hyperpolarization of common antifungal agents with SABRE.

Magn Reson Chem 2021 Jun 13. Epub 2021 Jun 13.

Department of Chemistry, North Carolina State University, Raleigh, NC, 27606, United States.

Signal amplification by reversible exchange (SABRE) is a robust and inexpensive hyperpolarization (HP) technique to enhance nuclear magnetic resonance (NMR) spectroscopy and magnetic resonance imaging (MRI) signals using parahydrogen (pH ). The substrate scope of SABRE is continually expanding. Here, we present the polarization of three antifungal drugs (voriconazole, clotrimazole and fluconazole) and elicit the detailed HP mechanisms for H and N nuclei. Read More

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Carambola-like BiTe superstructures with enhanced photoabsorption for highly efficient photothermal therapy in the second near-infrared biowindow.

J Mater Chem B 2021 Jun 14. Epub 2021 Jun 14.

State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry (CIAC), Chinese Academy of Sciences, Changchun 130022, China. and University of Science and Technology of China, Hefei 230026, China and Department of Chemistry, Tsinghua University, Beijing 100084, China.

Photothermal therapy (PTT) stimulated by light in the second near-infrared (NIR-II) biowindow shows great superiorities in the penetration ability of tissue and maximum permissible exposure (MPE). Exploring new photothermal agents with good optical absorbance in the NIR-II region is highly desirable for efficient cancer therapy. Herein, we successfully prepare carambola-like bismuth telluride (Bi2Te3) superstructures modified with PEGylated phospholipid ([email protected]) for CT imaging-guided PTT in the NIR-II biowindow. Read More

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Virtual non-contrast enhanced magnetic resonance imaging (VNC-MRI).

Magn Reson Imaging 2021 Jun 11;81:67-74. Epub 2021 Jun 11.

Department of Diagnostic and Interventional Neuroradiology, University Hospital Hamburg-Eppendorf, Building W14, Martinistr. 52, 20251 Hamburg, Germany.

Purpose: Application of contrast agents (CA) is widely used in various clinical fields like oncology. Similar to approaches used in computed tomography, virtual non-contrast enhanced (VNC) images can be generated with the goal to supersede true non-contrast enhanced (TNC) images.

Methods: In MRI a T1-mapping sequence with variable flip angle (VFA) was used to acquire two images with different image contrast at the same time. Read More

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Impact of superparamagnetic iron oxide nanoparticles on in vitro and in vivo radiosensitisation of cancer cells.

Radiat Oncol 2021 Jun 12;16(1):104. Epub 2021 Jun 12.

Patrick G. Johnston Centre for Cancer Research, Queen's University, Belfast, UK.

Purpose: The recent implementation of MR-Linacs has highlighted theranostic opportunities of contrast agents in both imaging and radiotherapy. There is a lack of data exploring the potential of superparamagnetic iron oxide nanoparticles (SPIONs) as radiosensitisers. Through preclinical 225 kVp exposures, this study aimed to characterise the uptake and radiobiological effects of SPIONs in tumour cell models in vitro and to provide proof-of-principle application in a xenograft tumour model. Read More

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Ultrasound contrast agents: microbubbles made simple for the pediatric radiologist.

Pediatr Radiol 2021 Jun 12. Epub 2021 Jun 12.

Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd, Philadelphia, PA, 19104, USA.

The ability to provide prompt, real-time, easily accessible and radiation-free diagnostic assessments makes ultrasound (US) one of the most versatile imaging modalities. The introduction and development of stable microbubble-based ultrasound contrast agents (UCAs) in the early 1990s improved visualization of complex vascular structures, overcoming some of the limitations of B-mode and Doppler imaging. UCAs have been used extensively in the adult population to visualize vasculature and to evaluate perfusion and blood flow dynamics in organs and lesions. Read More

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Quantitative perfusion histogram parameters of dynamic contrast-enhanced MRI to identify different pathological types of uterine leiomyoma.

Zhejiang Da Xue Xue Bao Yi Xue Ban 2021 Feb;50(1):97-105

Department of Radiology,Shaoxing People's Hospital,Shaoxing 312000,Zhejiang Province,China.

:To explore the value of quantitative perfusion histogram parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in pathological classification of uterine leiomyoma and its correlation with Ki-67 protein expression. Thirty five patients with uterine leiomyoma confirmed by operation and pathology at Shaoxing People's Hospital from October 2015 to September 2017 were analyzed retrospectively,including 15 cases of ordinary type,8 cases of cellular type and 12 cases of degenerative type. All patients were examined by pelvic DCE-MRI before operation,and the histogram parameters (median,mean,skewness,kurtosis,energy,entropy) of various quantitative perfusion parameters,including volume transport constant (K),rate constant (K),extravascular extracellular space distribute volume per unit tissue volume (V),blood plasma volume per unit volume of tissue (V) were calculated,and the efficacy of different parameters in pathological classification of uterine leiomyoma was evaluated by ROC curve. Read More

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February 2021

Infrared-Emitting Multimodal Nanostructures for Controlled In Vivo Magnetic Hyperthermia.

Adv Mater 2021 Jun 12:e2100077. Epub 2021 Jun 12.

Nanomaterials for Bioimaging Group (nanoBIG), Universidad Autónoma de Madrid, Madrid, 28049, Spain.

Deliberate and local increase of the temperature within solid tumors represents an effective therapeutic approach. Thermal therapies embrace this concept leveraging the capability of some species to convert the absorbed energy into heat. To that end, magnetic hyperthermia (MHT) uses magnetic nanoparticles (MNPs) that can effectively dissipate the energy absorbed under alternating magnetic fields. Read More

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Bleeding complications in patients with squamous cell carcinoma of the head and neck.

Head Neck 2021 Jun 12. Epub 2021 Jun 12.

Head and Neck Medical Oncology Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy.

Hemorrhage in recurrent and/or metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) may be attributed to chemotherapy and local tumor irradiation. Evidence of the relationship between hemorrhage in R/M HNSCC and targeted therapies, including epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) inhibitors, or immune checkpoint inhibitors, is limited. We aimed to identify epidemiological and clinical data related to the occurrence of hemorrhage in R/M HNSCC and to explore its relationship with various therapies. Read More

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How does artificial intelligence in radiology improve efficiency and health outcomes?

Pediatr Radiol 2021 Jun 12. Epub 2021 Jun 12.

Department of Medical Imaging, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.

Since the introduction of artificial intelligence (AI) in radiology, the promise has been that it will improve health care and reduce costs. Has AI been able to fulfill that promise? We describe six clinical objectives that can be supported by AI: a more efficient workflow, shortened reading time, a reduction of dose and contrast agents, earlier detection of disease, improved diagnostic accuracy and more personalized diagnostics. We provide examples of use cases including the available scientific evidence for its impact based on a hierarchical model of efficacy. Read More

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Pediatric contrast-enhanced ultrasound: shedding light on the pursuit of approval in the United States.

Pediatr Radiol 2021 Jun 11. Epub 2021 Jun 11.

Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN, USA.

For two decades, pediatric contrast US has been well accepted throughout Europe and other parts of the world outside the United States because of its high diagnostic efficacy and extremely favorable safety profile. This includes intravenous (IV) administration, contrast-enhanced US (CEUS) and the intravesical application, contrast-enhanced voiding urosonography (ceVUS). However, the breakthrough for pediatric contrast US in the United States did not come until 2016, when the U. Read More

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Is Contrast Medium Really Needed for Follow-up MRI of Untreated Intracranial Meningiomas?

AJNR Am J Neuroradiol 2021 Jun 11. Epub 2021 Jun 11.

From the Division of Neuroradiology (J.B., A.F., M.I.V.), Geneva University Hospital and Faculty of Medicine of Geneva, Geneva, Switzerland.

Background And Purpose: Recent concerns relating to tissue deposition of gadolinium are favoring the use of noncontrast MR imaging whenever possible. The purpose of this study was to assess the necessity of gadolinium contrast for follow-up MR imaging of untreated intracranial meningiomas.

Materials And Methods: One-hundred twenty-two patients (35 men, 87 women) with meningiomas who underwent brain MR imaging between May 2007 and May 2019 in our institution were included in this retrospective cohort study. Read More

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Efficacy and safety analysis of dexamethasone-lipiodol emulsion in prevention of post-embolization syndrome after TACE: a retrospective analysis.

BMC Gastroenterol 2021 Jun 11;21(1):256. Epub 2021 Jun 11.

Department of Radiology, Wuhan Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Jiefang Avenue #1277, Wuhan, 430022, China.

Background: To investigate the efficacy and safety of dexamethasone-lipiodol emulsion in the prevention of post-embolization syndrome after TACE.

Method: The data of 255 patients who underwent TACE in the interventional department from June 2017 to June 2020 were collected. This is a retrospective assessment of patients who were non-randomly treated with dexamethasone in TACE. Read More

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