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https://www.readbyqxmd.com/read/29457287/zero-te-based-pseudo-ct-image-conversion-in-the-head-and-its-application-in-pet-mr-attenuation-correction-and-mr-guided-radiation-therapy-planning
#1
Florian Wiesinger, Mikael Bylund, Jaewon Yang, Sandeep Kaushik, Dattesh Shanbhag, Sangtae Ahn, Joakim H Jonsson, Josef A Lundman, Thomas Hope, Tufve Nyholm, Peder Larson, Cristina Cozzini
PURPOSE: To describe a method for converting Zero TE (ZTE) MR images into X-ray attenuation information in the form of pseudo-CT images and demonstrate its performance for (1) attenuation correction (AC) in PET/MR and (2) dose planning in MR-guided radiation therapy planning (RTP). METHODS: Proton density-weighted ZTE images were acquired as input for MR-based pseudo-CT conversion, providing (1) efficient capture of short-lived bone signals, (2) flat soft-tissue contrast, and (3) fast and robust 3D MR imaging...
February 18, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29456769/a-case-of-schwannoma-of-the-submandibular-region
#2
Babatunde O Bamgbose, Akiko Sato, Yoshinobu Yanagi, Miki Hisatomi, Yohei Takeshita, Irfan Sugianto, Junichi Asaumi
Background: We herein described a rare case of schwannoma of the hypoglossal nerve in the submandibular region with diagnostic imaging and histopathological findings. Case Report: A 31-years-old woman has had a palpable firm, rubbery, freely mobile mass in the submandibular region. Of imaging, MR images showed homogeneous isointensity on T1-weighted imaging (T1-WI), heterogeneous hypointensity on T2-WI, heterogeneous hyperintensity on short T1 inversion recovery (STIR), and heterogeneous enhancement on contrast-enhanced T1-WI...
2018: Open Dentistry Journal
https://www.readbyqxmd.com/read/29456716/transient-severe-motion-during-arterial-phase-in-patients-with-gadoxetic-acid-administration-can-a-five-hepatic-arterial-subphases-technique-mitigate-the-artifact
#3
Yu-Dong Xiao, Cong Ma, Jun Liu, Hua-Bing Li, Shun-Ke Zhou, Zi-Shu Zhang
Gadoxetic acid (Gd-EOB-DTPA) is a hepatocyte-specific magnetic resonance (MR) contrast agent, which has been increasingly used in recent years. However, it has been reported that Gd-EOB-DTPA related transient severe motion (TSM) is sometimes observed during the hepatic arterial phase of MR imaging, which may influence image quality. Since the hepatic arterial phase of contrast enhancement is used for the diagnosis of hepatocellular carcinoma, it is crucial to obtain a decent arterial phase imaging. The present study analyzed motion in patients receiving Gd-EOB-DTPA, comparing a single arterial phase acquisition to a five arterial phase acquisition to determine whether the multiphase acquisition was able to alleviate the TSM-related hepatic arterial MR imaging artifact...
March 2018: Experimental and Therapeutic Medicine
https://www.readbyqxmd.com/read/29455905/ventriculoperitoneal-shunt-treatment-in-a-pregnant-renal-transplant-recipient-with-idiopathic-intracranial-hypertension-case-report-and-review-of-the-literature
#4
Ebru Apaydın Doğan, Selen Doğan, Ethem Taner Göksu, Sibel Özkaynak, Çile Aktan, İnanç Mendilcioğlu
Idiopathic intracranial hypertension (IIH) is a relatively uncommon disorder characterised by raised intracranial pressure without an established pathogenesis. Diagnosis of IIH requires the demonstration of symptoms and signs referable only to elevated intracranial pressure; cerebrospinal fluid (CSF) opening pressure >25cm H2 O measured in the lateral decubitus position; normal CSF composition; and no evidence for an underlying structural cause demonstrated by using MRI or contrast-enhanced CT scan for typical patients and MRI and MR venography for atypical patients such as man, children and those with low body mass index...
February 6, 2018: Neurologia i Neurochirurgia Polska
https://www.readbyqxmd.com/read/29450606/combination-transarterial-chemoembolization-and-microwave-ablation-improves-local-tumor-control-for-3-to-5-cm-hepatocellular-carcinoma-when-compared-with-transarterial-chemoembolization-alone
#5
Amanda R Smolock, Mircea M Cristescu, Audrey Hinshaw, Kaitlin M Woo, Shane A Wells, Timothy J Ziemlewicz, Meghan G Lubner, Prasad S Dalvie, J Louis Hinshaw, Christopher L Brace, Orhan S Ozkan, Fred T Lee, Paul Laeseke
PURPOSE: To compare transarterial chemoembolization (TACE) monotherapy to combination TACE and microwave ablation (MWA) for local control of 3- to 5-cm hepatocellular carcinoma (HCC). METHODS: Patients with HCC between 3 and 5 cm treated with TACE monotherapy or combination TACE + MWA at a single institution between 2007 and 2016 were retrospectively reviewed. Twenty-four HCCs (median diameter 3.8 cm) in 16 patients (13 males; median age 64 years) were treated using TACE monotherapy...
February 15, 2018: Abdominal Radiology
https://www.readbyqxmd.com/read/29448967/facial-nerve-stimulation-in-normal-pigs-and-healthy-human-volunteers-transitional-development-of-a-medical-device-for-the-emergency-treatment-of-ischemic-stroke
#6
Olivia Sanchez, Andrea García, Fernando Castro-Prado, Miriam Perez, Rafael Lara-Estrada, Martin Ramirez-Meza, Montserrat Godinez, Michael L Coco, Joaquín Azpiroz, Mark K Borsody, Emilio Sacristán
BACKGROUND: Magnetic stimulation of the facial nerve has been tested in preclinical studies as a new, non-invasive emergency treatment of ischemic stroke that acts by increasing cerebral blood flow (CBF). The objective of the studies reported herein was to identify minimal stimulation parameters that increase CBF in large animals and then test those stimulation parameters in healthy volunteers for safety, tolerability, and effectiveness at increasing CBF. This translational research is necessary preparation for clinical studies in ischemic stroke patients...
February 15, 2018: Journal of Translational Medicine
https://www.readbyqxmd.com/read/29448628/functionalized-magnetic-plga-nanospheres-for-targeting-and-bioimaging-of-breast-cancer
#7
Seung-Jun Lee, Hee-Jin Kim, Yong-Min Huh, Il Won Kim, Jae Hyun Jeong, Jin-Chul Kim, Jong-Duk Kim
Superparamagnetic iron oxide nanoparticles (SPIONs) are actively used as highly sensitive imaging probes to provide contrast in MRI. In this study, we propose the use of SPIONs encapsulated with antibody-conjugated poly(lactic-co-glycolic acid) (PLGA) as a potent theragnostic agent. The SPIONs were synthesized by a chemical co-precipitation method of ferric and ferrous ions, and subsequently encapsulated with PLGA by using an emulsification-diffusion method. Herceptin was chemically conjugated to the SPION-encapsulating PLGA nanoparticles to target the human epidermal growth factor receptor 2 (Her2/neu) overexpressing breast cancers...
March 1, 2018: Journal of Nanoscience and Nanotechnology
https://www.readbyqxmd.com/read/29446125/feasibility-of-high-spatiotemporal-resolution-for-an-abbreviated-3d-radial-breast-mri-protocol
#8
Jorge E Jimenez, Roberta M Strigel, Kevin M Johnson, Leah C Henze Bancroft, Scott B Reeder, Walter F Block
PURPOSE: To develop a volumetric imaging technique with 0.8-mm isotropic resolution and 10-s/volume rate to detect and analyze breast lesions in a bilateral, dynamic, contrast-enhanced MRI exam. METHODS: A local low-rank temporal reconstruction approach that also uses parallel imaging and spatial compressed sensing was designed to create rapid volumetric frame rates during a contrast-enhanced breast exam (vastly undersampled isotropic projection [VIPR] spatial compressed sensing with temporal local low-rank [STELLR])...
February 14, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29445714/brain-volume-estimation-enhancement-by-morphological-image-processing-tools
#9
R Zeinali, A Keshtkar, A Zamani, N Gharehaghaji
Background: Volume estimation of brain is important for many neurological applications. It is necessary in measuring brain growth and changes in brain in normal/abnormal patients. Thus, accurate brain volume measurement is very important. Magnetic resonance imaging (MRI) is the method of choice for volume quantification due to excellent levels of image resolution and between-tissue contrast. Stereology method is a good method for estimating volume but it requires to segment enough MRI slices and have a good resolution...
December 2017: Journal of Biomedical Physics & Engineering
https://www.readbyqxmd.com/read/29444856/placental-physiology-monitored-by-hyperpolarized-dynamic-13-c-magnetic-resonance
#10
Stefan Markovic, Anne Fages, Tangi Roussel, Ron Hadas, Alexander Brandis, Michal Neeman, Lucio Frydman
Placental functions, including transport and metabolism, play essential roles in pregnancy. This study assesses such processes in vivo , from a hyperpolarized MRI perspective. Hyperpolarized urea, bicarbonate, and pyruvate were administered to near-term pregnant rats, and all metabolites displayed distinctive behaviors. Little evidence of placental barrier crossing was observed for bicarbonate, at least within the timescales allowed by 13 C relaxation. By contrast, urea was observed to cross the placental barrier, with signatures visible from certain fetal organs including the liver...
February 14, 2018: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/29442708/aptamer-targeted-magnetic-resonance-imaging-contrast-agents-and-their-applications
#11
Yajie Zhang, Tingting Zhang, Min Liu, Ye Kuang, Guangyue Zu, Kunchi Zhang, Yi Cao, Renjun Pei
Magnetic resonance imaging is a powerful diagnostic technology with high spatial resolution and non-invasion. The contrast agents have significant effect on the resolution of the MR imaging. However, the commercial contrast agents (CAs) usually consist of individual Gd3+ chelated with a low molecular weight acyclic or cyclic ligand, and these small-molecule CAs are usually subjected to nonspecificity, thus leading to rapid renal clearance and modest contrast enhancement for tumor imaging. In recent years, the nanostructured materials conjugated with aptamers were widely used and opened a new door in biomedical imaging due to excellent specificity, non-immunogenicity, easily synthesis and chemical modification of aptamers...
June 1, 2018: Journal of Nanoscience and Nanotechnology
https://www.readbyqxmd.com/read/29440620/quantification-of-hepatic-perfusion-and-hepatocyte-function-with-dynamic-gadoxetic-acid-enhanced-mr-imaging-in-patients-with-chronic-liver-disease
#12
Benjamin Leporq, Jean-Luc Daire, Catherine M Pastor, Pierre Deltenre, Christine Sempoux, Sabine Schmidt, Bernard E Van Beers
The purpose of this study was to develop and perform initial validation of dynamic MR imaging enhanced with gadoxetic acid as hepatobiliary contrast agent to quantify hepatic perfusion and hepatocyte function in patients with chronic liver disease. Free-breathing, dynamic gadoxetic acid-enhanced MR imaging was performed at 3.0 T using a three-dimensional time-resolved angiography sequence with stochastic trajectories during 38 minutes. A dual-input three-compartment model was developed to derive hepatic perfusion and hepatocyte function parameters...
February 12, 2018: Clinical Science (1979-)
https://www.readbyqxmd.com/read/29440326/multiparametric-mri-of-intracranial-aneurysms-treated-with-the-woven-endobridge-web-a-case-of-faraday-s-cage
#13
Marie Teresa Nawka, Jan Sedlacik, Andreas Frölich, Maxim Bester, Jens Fiehler, Jan-Hendrik Buhk
OBJECTIVE: To evaluate multiparametric MRI including non-contrast and contrast-enhanced morphological and angiographic techniques for intracranial aneurysms treated with the single-layer Woven EndoBridge (WEB) embolization system applying simultaneous digital subtraction angiography (DSA) as the reference of standard. MATERIALS AND METHODS: We retrospectively identified all patients with incidental and acute ruptured intracranial aneurysms treated with a WEB device (WEB SL and WEB SLS) between March 2014 and June 2016 in our neurovascular center with early (within 7 days) postinterventional multiparametric MRI as well as mid-term (5-8 months) follow-up MRI and DSA available...
February 10, 2018: Journal of Neurointerventional Surgery
https://www.readbyqxmd.com/read/29439125/evaluation-of-leptomeningeal-contrast-enhancement-using-pre-and-postcontrast-subtraction-3d-flair-imaging-in-multiple-sclerosis
#14
R Zivadinov, D P Ramasamy, J Hagemeier, C Kolb, N Bergsland, F Schweser, M G Dwyer, B Weinstock-Guttman, D Hojnacki
BACKGROUND AND PURPOSE: Leptomeningeal contrast enhancement is found in patients with multiple sclerosis, though reported rates have varied. The use of 3D-fluid-attenuated inversion recovery pre- and postcontrast subtraction imaging may more accurately determine the frequency of leptomeningeal contrast enhancement. The purpose of this study was to investigate the frequency of leptomeningeal contrast enhancement using the pre- and postcontrast subtraction approach and to evaluate 3 different methods of assessing the presence of leptomeningeal contrast enhancement...
February 8, 2018: AJNR. American Journal of Neuroradiology
https://www.readbyqxmd.com/read/29437266/noninvasive-assessment-of-intracranial-elastance-and-pressure-in-spontaneous-intracranial-hypotension-by-mri
#15
Yi-Hsin Tsai, Hung-Chieh Chen, Hsin Tung, Yi-Ying Wu, Hsian-Min Chen, Kuan-Jung Pan, Da-Chuan Cheng, Jeon-Hor Chen, Clayton Chi-Chang Chen, Jyh-Wen Chai, Wu-Chung Shen
BACKGROUND: Spontaneous intracranial hypotension (SIH) is often misdiagnosed, and can lead to severe complications. Conventional MR sequences show a limited ability to aid in this diagnosis. MR-based intracranial pressure (MR-ICP) may be able to detect changes of intracranial elastance and pressure. PURPOSE: To determine whether MR-ICP is able to differentiate SIH patients from normal subjects, improve diagnostic sensitivity, and provide an insight into the pathophysiology...
February 13, 2018: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/29437167/dynamic-contrast-enhanced-magnetic-resonance-imaging-for-head-and-neck-cancers
#16
(no author information available yet)
Dynamic myraidpro contrast-enhanced magnetic resonance imaging (DCE-MRI) has been correlated with prognosis in head and neck squamous cell carcinoma as well as with changes in normal tissues. These studies implement different software, either commercial or in-house, and different scan protocols. Thus, the generalizability of the results is not confirmed. To assist in the standardization of quantitative metrics to confirm the generalizability of these previous studies, this data descriptor delineates in detail the DCE-MRI digital imaging and communications in medicine (DICOM) files with DICOM radiation therapy (RT) structure sets and digital reference objects (DROs), as well as, relevant clinical data that encompass a data set that can be used by all software for comparing quantitative metrics...
February 13, 2018: Scientific Data
https://www.readbyqxmd.com/read/29436506/non-enhanced-mr-imaging-for-preinterventional-assessment-of-the-angioarchitecture-in-vein-of-galen-malformations
#17
Nikola Reinhard Dürr, Waleed Brinjikji, Anne Pohrt, Henrich Lanfermann, Friedhelm Brassel, Dan Meila
BACKGROUND AND PURPOSE: Endovascular treatment of vein of Galen malformations (VGMs) requires sufficient preceding MR imaging. Standardized, preinterventional, non-invasive imaging has not been established. Our study is the first to examine the role of a dedicated, standardized, non-invasive imaging protocol in the evaluation of VGM angioarchitecture by non-contrast MRI/MR angiography. MATERIALS AND METHODS: We retrospectively evaluated a consecutive series of VGM patients who underwent a 1...
February 7, 2018: Journal of Neurointerventional Surgery
https://www.readbyqxmd.com/read/29436031/a-magnetofluorescent-carbon-dot-assembly-as-an-acidic-h-2-o-2-driven-oxygenerator-to-regulate-tumor-hypoxia-for-simultaneous-bimodal-imaging-and-enhanced-photodynamic-therapy
#18
Qingyan Jia, Jiechao Ge, Weimin Liu, Xiuli Zheng, Shiqing Chen, Yongmei Wen, Hongyan Zhang, Pengfei Wang
Recent studies indicate that carbon dots (CDs) can efficiently generate singlet oxygen (1 O2 ) for photodynamic therapy (PDT) of cancer. However, the hypoxic tumor microenvironment and rapid consumption of oxygen in the PDT process will severely limit therapeutic effects of CDs due to the oxygen-dependent PDT. Thus, it is becoming particularly important to develop a novel CD as an in situ tumor oxygenerator for overcoming hypoxia and substantially enhancing the PDT efficacy. Herein, for the first time, magnetofluorescent Mn-CDs are successfully prepared using manganese(II) phthalocyanine as a precursor...
February 13, 2018: Advanced Materials
https://www.readbyqxmd.com/read/29434453/faecal-calprotectin-and-magnetic-resonance-imaging-in-detecting-crohn-s-disease-endoscopic-postoperative-recurrence
#19
Pierre Baillet, Guillaume Cadiot, Marion Goutte, Felix Goutorbe, Hedia Brixi, Christine Hoeffel, Christophe Allimant, Maud Reymond, Hélène Obritin-Guilhen, Benoit Magnin, Gilles Bommelaer, Bruno Pereira, Constance Hordonneau, Anthony Buisson
AIM: To assess magnetic resonance imaging (MRI) and faecal calprotectin to detect endoscopic postoperative recurrence in patients with Crohn's disease (CD). METHODS: From two tertiary centers, all patients with CD who underwent ileocolonic resection were consecutively and prospectively included. All the patients underwent MRI and endoscopy within the first year after surgery or after the restoration of intestinal continuity [median = 6 mo (5.0-9.3)]. The stools were collected the day before the colonoscopy to evaluate faecal calprotectin level...
February 7, 2018: World Journal of Gastroenterology: WJG
https://www.readbyqxmd.com/read/29434275/quantification-of-glioblastoma-mass-effect-by-lateral-ventricle-displacement
#20
Tyler C Steed, Jeffrey M Treiber, Michael G Brandel, Kunal S Patel, Anders M Dale, Bob S Carter, Clark C Chen
Mass effect has demonstrated prognostic significance for glioblastoma, but is poorly quantified. Here we define and characterize a novel neuroimaging parameter, lateral ventricle displacement (LVd), which quantifies mass effect in glioblastoma patients. LVd is defined as the magnitude of displacement from the center of mass of the lateral ventricle volume in glioblastoma patients relative to that a normal reference brain. Pre-operative MR images from 214 glioblastoma patients from The Cancer Imaging Archive (TCIA) were segmented using iterative probabilistic voxel labeling (IPVL)...
February 12, 2018: Scientific Reports
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