keyword
MENU ▼
Read by QxMD icon Read
search

MR Guided

keyword
https://www.readbyqxmd.com/read/28636763/sensitive-volume-effects-on-monte-carlo-calculated-ion-chamber-response-in-magnetic-fields
#1
Victor N Malkov, David W O Rogers
PURPOSE: The development of magnetic resonance guided radiation therapy (MR-gRT) necessitates accurate Monte Carlo (MC) models of ion chambers for computing ion chamber corrections to compensate for the presence of the magnetic field. This study evaluates the sensitivity of the ion chamber dose response in a magnetic field on the collection volume used in the MC simulation METHODS: The EGSnrc system's egs_chamber application is used with a recently developed and validated magnetic field transport code...
June 21, 2017: Medical Physics
https://www.readbyqxmd.com/read/28636564/radiation-dosimetry-in-magnetic-fields-with-farmer-type-ionization-chambers-determination-of-magnetic-field-correction-factors-for-different-magnetic-field-strengths-and-field-orientations
#2
Claudia Katharina Spindeldreier, Oliver Schrenk, Anna Bakenecker, Iwan Kawrakow, Lucas Norberto Burigo, Christian P Karger, Steffen Greilich, Asja Pfaffenberger
The aim of this work was to determine magnetic field correction factors that are needed for dosimetry in hybrid devices for MR-guided radiotherapy for Farmer-type ionization chambers for different magnetic field strengths and field orientations. The response of six custom-built Farmer-type chambers irradiated at a 6 MV linac was measured in a water tank positioned in a magnet with magnetic field strengths between 0.0 T and 1.1 T. Chamber axis, beam and magnetic field were perpendicular to each other and both magnetic field directions were investigated...
June 21, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28634521/a-review-of-echocardiograms-in-hypertensive-patients-greater-than-60-years-in-a-community-based-family-medicine-program
#3
Shideh Doroudi, Michael D DeLisi, Vincent A DeBari
Background: Heart disease as a result of Hypertension is known to occur. Anatomical and functional changes of the heart can easily be detected by echocardiography, which is a safe and readily available study. Objectives: The aims of this study were to evaluate the prevalence of common echocardiographic changes in chronic hypertensive patients and to compare these changes in male and female populations. Design/methods: The study was a community-based cross-sectional study, on 227 hypertensive patients, 60 years and older, seen in St...
January 2017: Journal of Community Hospital Internal Medicine Perspectives
https://www.readbyqxmd.com/read/28634148/iodine-and-freeze-drying-enhanced-high-resolution-microct-imaging-for-reconstructing-3d-intraneural-topography-of-human-peripheral-nerve-fascicles
#4
Liwei Yan, Yongze Guo, Jian Qi, Qingtang Zhu, Liqiang Gu, Canbin Zheng, Tao Lin, Yutong Yu, Zitao Zeng, Sha Yu, Shuang Zhu, Xiang Zhou, Xi Zhang, Yunfei Du, Zhi Yao, Yao Lu, Xiaolin Liu
BACKGROUND: The precise annotation and accurate identification of the topography of fascicles to the end organs are prerequisites for studying human peripheral nerves. NEW METHOD: In this study, we present a feasible imaging method that acquires 3D high-resolution (HR) topography of peripheral nerve fascicles using an iodine and freeze-drying (IFD) micro-computed tomography (microCT) method to greatly increase the contrast of fascicle images. RESULTS: The enhanced microCT imaging method can facilitate the reconstruction of high-contrast HR fascicle images, fascicle segmentation and extraction, feature analysis, and the tracing of fascicle topography to end organs, which define fascicle functions...
June 17, 2017: Journal of Neuroscience Methods
https://www.readbyqxmd.com/read/28633808/impact-of-mr-guided-boiling-histotripsy-in-distinct-murine-tumor-models
#5
Martijn Hoogenboom, Dylan C Eikelenboom, Renske J E van den Bijgaart, Arend Heerschap, Pieter Wesseling, Martijn H den Brok, Jurgen J Fütterer, Gosse J Adema
Interest in mechanical high intensity focused ultrasound (HIFU) ablation is rapidly growing. Boiling histotripsy (BH) is applied for mechanical fragmentation of soft tissue into submicron fragments with limited temperature increase using the shock wave and cavitation effects of HIFU. Research on BH has been largely limited to ex vivo experiments. As a consequence, the in vivo pathology after BH treatment and the relation to preexistent tissue characteristics are not well understood. This study reports on in vivo MR guided BH treatment, either with 100 or 200 pulses per focal spot, in three different subcutaneous mouse tumor models: a soft-tissue melanoma (B16OVA), a compact growing thymoma (EL4), and a highly vascularized neuroblastoma (9464D)...
September 2017: Ultrasonics Sonochemistry
https://www.readbyqxmd.com/read/28629785/-interest-using-3d-ultrasound-and-mri-fusion-biopsy-for-prostate-cancer-detection
#6
A Marien, A De Castro Abreu, I Gill, A Villers, O Ukimura
INTRODUCTION: The strategic therapy for prostate cancer depends on histo-pronostics data, which could be upgraded by obtaining targeted biopsies (TB) with MRI (magnetic resonance imagery) fusion 3D ultrasound. OBJECTIVES: To compare diagnostic yield of image fusion guided prostate biopsy using image fusion of multi-parametric MRI (mpMRI) with 3D-TRUS. MATERIALS AND METHODS: Between January 2010 and April 2013, 179 consecutive patients underwent outpatient TRUS biopsy using the real-time 3D TRUS tracking system (Urostation™)...
June 16, 2017: Progrès en Urologie
https://www.readbyqxmd.com/read/28626862/acoustic-field-characterization-of-a-clinical-magnetic-resonance-guided-high-intensity-focused-ultrasound-system-inside-the-magnet-bore
#7
Satya V V N Kothapalli, Michael B Altman, Ari Partanen, Leighton Wan, H Michael Gach, William Straube, Dennis E Hallahan, Hong Chen
PURPOSE: With the expanding clinical application of magnetic resonance-guided high intensity focused ultrasound (MR-HIFU), acoustic field characterization of MR-HIFU systems is needed for facilitating regulatory approval and ensuring consistent and safe power output of HIFU transducers. However, the established acoustic field measurement techniques typically use equipment that cannot be used in a magnetic resonance imaging (MRI) suite, thus posing a challenge to the development and execution of HIFU acoustic field characterization techniques...
June 19, 2017: Medical Physics
https://www.readbyqxmd.com/read/28626558/multifunctional-mixed-metal-nanoscale-coordination-polymers-for-triple-modality-imaging-guided-photodynamic-therapy
#8
Yong-Mei Wang, Wei Liu, Xue-Bo Yin
The one-step self-assembly preparation of multifunctional gadolinium (Gd)-ytterbium (Yb) mixed-metal nanoscale coordination polymers (NCPs) with Ru[4,4'-(COOH)2bpy]3(2+) (LRu , bpy = bipyridyl) as a ligand is reported. The Gd/Yb ratio in the NCPs is easily tuned by their ratio in the precursors while the self-limiting growth is realized with the high coordination valence and rigid steric structure of the precursors. The inherent properties of the precursors, including the magnetic resonance (MR) response of Gd(3+), the X-ray attenuation properties of Yb(3+), and the red fluorescence and the singlet-oxygen generation of LRu , are well retained in the mixed-metal NCPs...
May 1, 2017: Chemical Science
https://www.readbyqxmd.com/read/28624005/differentiation-between-cholangiocarcinoma-and-hepatocellular-carcinoma-with-target-sign-on-diffusion-weighted-imaging-and-hepatobiliary-phase-gadoxetic-acid-enhanced-mr-imaging-classification-tree-analysis-applying-capsule-and-septum
#9
Ji Hye Min, Young Kon Kim, Seo-Youn Choi, Woo Kyoung Jeong, Won Jae Lee, Sang Yun Ha, Soohyun Ahn, Hyeon Seon Ahn
OBJECTIVES: To assess the usefulness of classification tree analysis (CTA) for discrimination of hepatocellular carcinoma (HCC) with target sign on hepatobiliary phase (HBP) and/or diffusion-weighted image (DWI) from intrahepatic cholangiocarcinoma (ICC). METHODS: This retrospective study was approved by the institutional review board. From among the 811 patients with histopathologically proven 79 ICCs and 732 HCCs, 69 patients with 69 (87.3%) ICCs and 115 patients with 115 HCCs (15...
July 2017: European Journal of Radiology
https://www.readbyqxmd.com/read/28621626/a-multimodal-concept-for-invasive-diagnostics-and-surgery-based-on-neuronavigated-voxel-based-morphometric-mri-postprocessing-data-in-previously-nonlesional-epilepsy
#10
Daniel Delev, Carlos M Quesada, Alexander Grote, Jan P Boström, Christian Elger, Hartmut Vatter, Rainer Surges
OBJECTIVE Diagnosis and surgical treatment of refractory and apparent nonlesional focal epilepsy is challenging. Morphometric MRI voxel-based and other postprocessing methods can help to localize the epileptogenic zone and thereby support the planning of further invasive electroencephalography (EEG) diagnostics, and maybe resective epilepsy surgery. METHODS The authors developed an algorithm to implement regions of interest (ROI), based on postprocessed MRI data, into a neuronavigation tool. This was followed by stereotactic ROI-guided implantation of depth electrodes and ROI-navigated resective surgery...
June 16, 2017: Journal of Neurosurgery
https://www.readbyqxmd.com/read/28621567/-68-ga-radiolabeled-aguix-nanoparticles-as-dual-modality-imaging-agents-for-pet-mri-guided-radiation-therapy
#11
Penelope Bouziotis, Dimitris Stellas, Eloïse Thomas, Charles Truillet, Charalampos Tsoukalas, François Lux, Theodoros Tsotakos, Stavros Xanthopoulos, Maria Paravatou-Petsotas, Anastasios Gaitanis, Lia Angela Moulopoulos, Vassilis Koutoulidis, Constantinos D Anagnostopoulos, Olivier Tillement
AIM: The aim of this study was to develop a dual-modality positron emission tomography/magnetic resonance (PET/MR) imaging probe by radiolabeling gadolinium-containing AGuIX derivatives with the positron-emitter Gallium-68 ((68)Ga). MATERIALS & METHODS: AGuIX@NODAGA nanoparticles were labeled with (68)Ga at high efficiency. Tumor accumulation in an appropriate disease model was assessed by ex vivo biodistribution and in vivo PET/MR imaging. RESULTS:  (68)Ga-AGuIX@NODAGA was proven to passively accumulate in U87MG human glioblastoma tumor xenografts...
June 16, 2017: Nanomedicine
https://www.readbyqxmd.com/read/28620939/engineering-novel-targeted-boron-10-enriched-theranostic-nanomedicine-to-combat-against-murine-brain-tumors-via-mr-imaging-guided-boron-neutron-capture-therapy
#12
Naresh Kuthala, Raviraj Vankayala, Yi-Nan Li, Chi-Shiun Chiang, Kuo Chu Hwang
Glioblastoma multiforme (GBM) is a very common type of "incurable" malignant brain tumor. Although many treatment options are currently available, most of them eventually fail due to its recurrence. Boron neutron capture therapy (BNCT) emerges as an alternative noninvasive therapeutic treatment modality. The major challenge in treating GBMs using BNCT is to achieve selective imaging, targeting, and sufficient accumulation of boron-containing drug at the tumor site so that effective destruction of tumor cells can be achieved without harming the normal brain cells...
June 16, 2017: Advanced Materials
https://www.readbyqxmd.com/read/28618069/optimization-of-acoustic-radiation-force-imaging-influence-of-timing-parameters-on-sensitivity
#13
Tetiana Dadakova, Axel Joachim Krafft, Ali Caglar Özen, Michael Bock
PURPOSE: Optimization of timing parameters for MR-guided ARFI to achieve the highest displacement signal-to-noise ratio (SNRd ). THEORY AND METHODS: In MR-guided ARFI the phase change induced by motion encoding gradients (MEGs) is measured to assess tissue displacement. The sensitivity of this encoding procedure depends on several timing parameters, such as the MEG duration and the offset time between ultrasound (US) and MEG. Furthermore, mechanical and MR tissue constants and MEG schemes (bipolar or three-lobed) influence SNRd ...
June 15, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28616966/magnetic-resonance-imaging-guided-multi-drug-chemotherapy-and-photothermal-synergistic-therapy-with-ph-and-nir-stimulation-release
#14
Jichun Yang, Yang Chen, Yu-Hao Li, Xue-Bo Yin
The combination of multi-drug chemotherapy and photothermal therapy (PTT) enhances cancer therapeutic efficacy. Herein, we develop a simple and smart pH/NIR dual-stimulus-responsive degradable mesoporous CoFe2O4@PDA@ZIF-8 sandwich nanocomposite. Mesoporous CoFe2O4 core acts as T2-weighted magnetic resonance (MR) imaging probe, PTT agent, and loading platform of hydrophilic doxorubicin (DOX). A polydopamine (PDA) layer is used to avoid the premature leakage of DOX before arriving at tumor site, enhance PTT efficiency, and facilitate the integration of ZIF-8 (a kind of metal-organic frameworks)...
June 15, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28616725/the-role-of-t1-perfusion-based-classification-in-magnetic-resonance-guided-high-intensity-focused-ultrasound-ablation-of-uterine-fibroids
#15
Bilgin Keserci, Nguyen Minh Duc
OBJECTIVE: To comparatively evaluate the role of magnetic resonance (MR) T1 perfusion-based time-signal intensity (SI) curves of fibroid tissue and the myometrium in classification of fibroids for predicting treatment outcomes of high-intensity focused ultrasound (HIFU) treatment. METHODS: The fibroids of 74 women who underwent MR-HIFU treatment were classified into group A (time-SI curve of fibroid lower than that of the myometrium) and group B (time-SI curve of fibroid equal to or higher than that of the myometrium)...
June 14, 2017: European Radiology
https://www.readbyqxmd.com/read/28616236/effect-of-applied-energy-in-renal-sympathetic-denervation-with-magnetic-resonance-guided-focused-ultrasound-in-a-porcine-model
#16
Jill Shea, Joshua de Bever, Eugene Kholmovski, Hannah Beal, J Rock Hadley, Emilee Minalga, Mohamed E Salama, Nassir F Marrouche, Allison Payne
BACKGROUND: Past catheter-based and focused ultrasound renal denervation studies have indicated that procedure efficacy is related to the number of ablations performed or the amount of energy used for the ablation. This study extends those prior results and investigates energy level effects on the efficacy of MR guided focused ultrasound renal denervation performed in a porcine model. METHODS: Twenty-four normotensive pigs underwent unilateral denervation at three intensity levels...
2017: Journal of Therapeutic Ultrasound
https://www.readbyqxmd.com/read/28613821/t1-t2-dual-modal-magnetic-resonance-imaging-from-molecular-basis-to-contrast-agents
#17
Zijian Zhou, Ruiliang Bai, Jeeva Munasinghe, Zheyu Shen, Liming Nie, Xiaoyuan Chen
Multimodal imaging strategies integrating manifold images have improved our ability to diagnose, to guide therapy, and to predict outcomes. Magnetic resonance imaging (MRI) is among the most widely used imaging technique in the clinic and can enable multiparameter anatomical demonstration of diagnosis. Due to the inherent black-and-white production of MR images, however, MRI detection is largely hampered by the occurrence of false-positive diagnoses. In this Perspective, we introduce the paradigm of manipulating the multiparameter MRI, T1-T2 dual-modal MRI, along with enhancement by specific contrast agents...
June 14, 2017: ACS Nano
https://www.readbyqxmd.com/read/28612288/magnetic-resonance-image-guidance-in-external-beam-radiation-therapy-planning-and-delivery
#18
REVIEW
Ilamurugu Arivarasan, Chandrasekaran Anuradha, Shanmuga Subramanian, Ayyalusamy Anantharaman, Velayudham Ramasubramanian
The use of magnetic resonance (MR) imaging in radiation oncology is improving dramatically. This review article discusses the necessity of image guidance and how MR finds a significant place in radiotherapy planning and delivery. The challenges to and current solutions for an in-house MR simulation, dedicated MR simulator, estimation of electron density using MR image sets and development of MR-compatible treatment planning systems are presented. This article also reviews the feasibility, advantages and limitations of MR image-guided radiation therapy (MR-IGRT) and its drive toward the integration of radiation beams with MR technology...
June 13, 2017: Japanese Journal of Radiology
https://www.readbyqxmd.com/read/28608119/breast-specific-sensuality-and-sexual-function-in-cancer-survivorship-does-surgical-modality-matter
#19
Jennifer S Gass, Michaela Onstad, Sarah Pesek, Kristin Rojas, Sara Fogarty, Ashley Stuckey, Christina Raker, Don S Dizon
PURPOSE: More early-staged breast cancer patients are choosing mastectomy. No studies have addressed breast-specific sensuality (BSS), defined as the breast's role during intimacy. We explored BSS among women undergoing lumpectomy (L), mastectomy alone (M), or with reconstruction (MR) and analyzed the association of surgical modality with sexual function. METHODS: Women undergoing breast cancer surgery between 2000 and 2013 were eligible for survey using investigator-generated questions and the Female Sexual Function Index (FSFI)...
June 12, 2017: Annals of Surgical Oncology
https://www.readbyqxmd.com/read/28606358/mid-regional-pro-adrenomedullin-and-st2-in-heart-failure-contributions-to-diagnosis-and-prognosis
#20
REVIEW
Daniela Lopes, Luiz Menezes Falcão
Heart failure has a high prevalence in developed countries. It is a frequent cause of hospital admission and has an important impact on morbidity, mortality and healthcare costs. Biomarkers have been widely studied in heart failure, as they improve diagnosis and prognostic assessment. Natriuretic peptides are already a part of daily clinical practice but several other biomarkers are being studied. This review focuses on mid-regional pro-adrenomedullin (MR-proADM) and ST2. Neither of these biomarkers is useful in the diagnosis of acute heart failure...
June 9, 2017: Portuguese Journal of Cardiology: An Official Journal of the Portuguese Society of Cardiology
keyword
keyword
55733
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"