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https://www.readbyqxmd.com/read/28738344/quantitative-low-dose-computed-tomography-of-the-lung-parenchyma-and-airways-for-the-differentiation-between-chronic-obstructive-pulmonary-disease-and-asthma-patients
#1
Huai Chen, Qing-Si Zeng, Min Zhang, Rong-Chang Chen, Ting-Ting Xia, Wei Wang, Xiaoyin Xu, Yubao Guan
BACKGROUND: It is difficult to differentiate between chronic obstructive pulmonary disease (COPD) and asthma in clinics; therefore, for diagnostic purposes, imaging-based measurements could be beneficial to differentiate between the two diseases. OBJECTIVES: We aim to analyze quantitative measurements of the lung and bronchial parameters that are provided by low-dose computed tomography (CT) to differentiate COPD and asthma from an imaging perspective. MATERIALS AND METHODS: 69 COPD patients, 52 asthma patients, and 20 healthy subjects were recruited to participate in CT imaging and pulmonary function tests (PFTs)...
July 25, 2017: Respiration; International Review of Thoracic Diseases
https://www.readbyqxmd.com/read/28737143/optimal-utilization-of-pediatric-computed-tomography-to-minimize-radiation-exposure-what-the-clinician-must-know-s
#2
Natasha Gupta, Lalendra Upreti
The number of computed tomography (CT) scans being done for children all over the world is on the rise ever since the advent of Multi-Detector CT (MDCT). However, CT is a potential source of harmful ionizing radiation, and children are more susceptible to its adverse effects. It is essential for the pediatrician as well as the radiologist to be aware of some important principles and guidelines, by following which, radiation exposure to the child can be minimized to the bare essential. It is important to have knowledge of the valid and justifiable indications of CT for the child, the correct technique of performing the scan, and the new technological innovations now available on modern scanners that help to minimize radiation dose...
July 15, 2017: Indian Pediatrics
https://www.readbyqxmd.com/read/28735464/radiation-dose-reduction-in-thoracic-and-lumbar-spine-instrumentation-using-navigation-based-on-an-intraoperative-cone-beam-ct-imaging-system-a-prospective-randomized-clinical-trial
#3
Nathalie Pireau, Virginie Cordemans, Xavier Banse, Nadia Irda, Sébastien Lichtherte, Ludovic Kaminski
PURPOSE: Spine surgery still remains a challenge for every spine surgeon, aware of the potential serious outcomes of misplaced instrumentation. Though many studies have highlighted that using intraoperative cone beam CT imaging and navigation systems provides higher accuracy than conventional freehand methods for placement of pedicle screws in spine surgery, few studies are concerned about how to reduce radiation exposure for patients with the use of such technology. One of the main focuses of this study is based on the ALARA principle (as low as reasonably achievable)...
July 22, 2017: European Spine Journal
https://www.readbyqxmd.com/read/28735255/ascending-aortic-diameter-and-metabolic-syndrome-in-korean-men
#4
Hyejin Chun
This study aimed to evaluate the association of ascending aortic diameter (AAD) measured by low-dose chest CT (LDCT) and metabolic syndrome (MS) in Korean men. AAD was measured with LDCT in 1046 healthy Korean men (mean age 50.7±9.7 years, range 28 to 69 years) participating in medical health check-up in a university health promotion center. AAD was defined as the longest length measured from the left main coronary ostium to the level of the right pulmonary artery in the axial plane in LDCT. The association between AAD and MS was examined using logistic regression...
July 21, 2017: Journal of Investigative Medicine: the Official Publication of the American Federation for Clinical Research
https://www.readbyqxmd.com/read/28734730/multifaceted-c-x-c-chemokine-receptor-4-inhibition-interferes-with-anti-vascular-endothelial-growth-factor-therapy-induced-glioma-dissemination
#5
Jean-Pierre Gagner, Yasmeen Sarfraz, Valerio Ortenzi, Fawaz M Alotaibi, Luis A Chiriboga, Awab T Tayyib, Garry J Douglas, Eric Chevalier, Barbara Romagnoli, Gérald Tuffin, Michel Schmitt, Guillaume Lemercier, Klaus Dembowsky, David Zagzag
Resistance to antiangiogenic therapy glioblastoma (GBM) patients may involve hypoxia-induced expression of stromal cell-derived factor (SDF)-1α receptor C-X-C chemokine receptor 4 (CXCR4) on invading tumor, macrophage/microglial cells (MGCs), and glioma stem cells (GSCs). We determined whether antagonizing CXCR4 with peptide epitope mimetic POL5551 disrupts anti-vascular endothelial growth factor therapy-induced glioma growth and dissemination. Mice bearing orthotopic CT-2A or GL261 gliomas received POL5551 and/or anti-vascular endothelial growth factor antibody B20-4...
July 20, 2017: American Journal of Pathology
https://www.readbyqxmd.com/read/28733723/an-individualized-radiation-dose-escalation-trial-in-non-small-cell-lung-cancer-based-on-fdg-pet-imaging
#6
Marie Wanet, Antoine Delor, François-Xavier Hanin, Benoît Ghaye, Aline Van Maanen, Vincent Remouchamps, Christian Clermont, Samuel Goossens, John Aldo Lee, Guillaume Janssens, Anne Bol, Xavier Geets
AIM: The aim of the study was to assess the feasibility of an individualized 18F fluorodeoxyglucose positron emission tomography (FDG-PET)-guided dose escalation boost in non-small cell lung cancer (NSCLC) patients and to assess its impact on local tumor control and toxicity. PATIENTS AND METHODS: A total of 13 patients with stage II-III NSCLC were enrolled to receive a dose of 62.5 Gy in 25 fractions to the CT-based planning target volume (PTV; primary turmor and affected lymph nodes)...
July 21, 2017: Strahlentherapie und Onkologie: Organ der Deutschen Röntgengesellschaft ... [et Al]
https://www.readbyqxmd.com/read/28732226/intermittent-administration-of-parathyroid-hormone-ameliorated-alveolar-bone-loss-in-experimental-periodontitis-in-streptozotocin-induced-diabetic-rats
#7
Helin Chen, Taozi Fu, Yuanyuan Ma, Xiangnan Wu, Xianxian Li, Xinyi Li, Jiefei Shen, Hang Wang
OBJECTIVE: Intermittent administration of parathyroid hormone (PTH) has been demonstrated to have anabolic effects on bone metabolism and is approved for use in the treatment of osteoporosis. This study evaluates the role of intermittent PTH administration on alveolar bone loss in streptozotocin (STZ)-induced diabetic rats. DESIGN: Fifty male Sprague Dawley rats were randomly divided into the following five groups: (1) a control group (saline placebo without ligature and STZ injection), (2) a PTH group (PTH administration without ligature and STZ injection), (3) an L group (saline placebo with ligature), (4) an L+STZ group (saline placebo with ligature and STZ injection), and (5) an L+STZ+PTH group (PTH administration with ligature and STZ injection)...
July 5, 2017: Archives of Oral Biology
https://www.readbyqxmd.com/read/28729729/a-novel-methodology-using-ct-imaging-biomarkers-to-quantify-radiation-sensitivity-in-the-esophagus-with-application-to-clinical-trials
#8
Joshua S Niedzielski, Jinzhong Yang, Francesco Stingo, Zhongxing Liao, Daniel Gomez, Radhe Mohan, Mary Martel, Tina Briere, Laurence Court
Personalized cancer therapy seeks to tailor treatment to an individual patient's biology. Therefore, a means to characterize radiosensitivity is necessary. In this study, we investigated radiosensitivity in the normal esophagus using an imaging biomarker of radiation-response and esophageal toxicity, esophageal expansion, as a method to quantify radiosensitivity in 134 non-small-cell lung cancer patients, by using K-Means clustering to group patients based on esophageal radiosensitivity. Patients within the cluster of higher response and lower dose were labelled as radiosensitive...
July 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28728443/functional-assessment-of-coronary-artery-disease-by-cardiac-computed-tomography
#9
T A Treibel, A Rossi, F Pugliese, C Davies
Rapid technological advances in computed tomography (CT) have allowed CT coronary angiography (CTCA) to be delivered at low radiation dose and high diagnostic accuracy. Due to its high negative predictive value for coronary artery disease, it has become a gatekeeper for the assessment of patients with chest pain of recent onset. Second line functional assessment of a detected coronary stenosis relies mostly on other imaging modalities. Functional assessment of coronary artery disease by CT is therefore an attractive addition to CTCA...
July 21, 2017: Expert Review of Cardiovascular Therapy
https://www.readbyqxmd.com/read/28726684/low-dose-4d-cone-beam-ct-via-joint-spatiotemporal-regularization-of-tensor-framelet-and-nonlocal-total-variation
#10
Hao Han, Hao Gao, Lei Xing
Excessive radiation exposure is still a major concern in 4D cone-beam computed tomography (4D-CBCT) due to its prolonged scanning duration. Radiation dose can be effectively reduced by either under-sampling the x-ray projections or reducing the x-ray flux. However, 4D-CBCT reconstruction under such low-dose protocols is prone to image artifacts and noise. In this work, we propose a novel joint regularization-based iterative reconstruction method for low-dose 4D-CBCT. To tackle the under-sampling problem, we employ spatiotemporal tensor framelet (STF) regularization to take advantage of the spatiotemporal coherence of the patient anatomy in 4D images...
July 20, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28726679/accuracy-of-rhenium-188-spect-ct-activity-quantification-for-applications-in-radionuclide-therapy-using-clinical-reconstruction-methods
#11
Pedro L Esquinas, Carlos F Uribe, M Gonzalez, Cristina Rodríguez-Rodríguez, Urs O Häfeli, Anna Celler
The main applications of (188)Re in radionuclide therapies include trans-arterial liver radioembolization and palliation of painful bone-metastases. In order to optimize (188)Re therapies, the accurate determination of radiation dose delivered to tumors and organs at risk is required. Single photon emission computed tomography (SPECT) can be used to perform such dosimetry calculations. However, the accuracy of dosimetry estimates strongly depends on the accuracy of activity quantification in (188)Re images...
July 20, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28726575/bioprinting-pattern-dependent-electrical-mechanical-behavior-of-cardiac-alginate-implants-characterization-and-ex-vivo-phase-contrast-microtomography-assessment
#12
Mohammad Izadifar, Paul Babyn, Michael E Kelly, Dean Chapman, Xiongbiao Chen
Three-dimensional (3D)-bioprinting techniques may be used to modulate electrical/mechanical properties and porosity of hydrogel constructs for fabrication of suitable cardiac implants. Notably, characterization of these properties after implantation remains a challenge, raising the need for the development of novel quantitative imaging techniques for monitoring hydrogel implant behavior in-situ. This study aims to (i) assess the influence of hydrogel bioprinting patterns on electrical/mechanical behavior of cardiac implants based on a 3D-printing technique and (ii) investigate the potential of synchrotron X-ray phase contrast computed tomography (PCI-CT) for estimating elastic modulus/impedance/porosity and microstructural features of 3D-printed cardiac implants in-situ via an ex-vivo study...
July 20, 2017: Tissue Engineering. Part C, Methods
https://www.readbyqxmd.com/read/28725938/declining-radiation-dose-of-coronary-computed-tomography-angiography-german-cardiac-ct-registry-experience-2009-2014
#13
Axel Schmermund, Mohamed Marwan, Jörg Hausleiter, Sebastian Barth, Oliver Bruder, Sebastian Kerber, Grigorius Korosoglou, Alexander Leber, Werner Moshage, Stephen Schröder, Steffen Schneider, Jochen Senges, Stephan Achenbach
BACKGROUND: Coronary computed tomography angiography (CTA) is increasingly used as a test to rule out coronary artery disease (CAD) in patients with a low to intermediate pre-test probability of the disease. We used the database of the German CT registry, collected between 2009 and 2014 in a broad patient population, to analyze contemporary radiation dose associated with coronary CTA in clinical practice. PATIENTS AND METHODS: The prospective observational registry included a total of 7061 patients ≥18 years, referred to 12 participating centers for a clinically indicated cardiac CT examination...
July 19, 2017: Clinical Research in Cardiology: Official Journal of the German Cardiac Society
https://www.readbyqxmd.com/read/28725253/computed-tomography-based-treatment-planning-for-high-dose-rate-brachytherapy-using-the-tandem-and-ring-applicator-influence-of-applicator-choice-on-organ-dose-and-inter-fraction-adaptive-planning
#14
REVIEW
Vishruta A Dumane, Yading Yuan, Ren-Dih Sheu, Vishal Gupta
Three dimensional planning for high-dose-rate (HDR) brachytherapy in cervical cancer has been highly recommended by consensus guidelines such as the American Brachytherapy Society (ABS) and the Groupe Européen de Curiethérapie - European Society for Radiotherapy and Oncology (GEC-ESTRO). In this document, we describe our experience with computed tomography (CT)-based planning using the tandem/ring applicator. We discuss the influence of applicator geometry on doses to organs at risk (OARs), namely the bladder, rectum, and sigmoid...
June 2017: Journal of Contemporary Brachytherapy
https://www.readbyqxmd.com/read/28725184/sevoflurane-induces-coherent-slow-delta-oscillations-in-rats
#15
Jennifer A Guidera, Norman E Taylor, Justin T Lee, Ksenia Y Vlasov, JunZhu Pei, Emily P Stephen, J Patrick Mayo, Emery N Brown, Ken Solt
Although general anesthetics are routinely administered to surgical patients to induce loss of consciousness, the mechanisms underlying anesthetic-induced unconsciousness are not fully understood. In rats, we characterized changes in the extradural EEG and intracranial local field potentials (LFPs) within the prefrontal cortex (PFC), parietal cortex (PC), and central thalamus (CT) in response to progressively higher doses of the inhaled anesthetic sevoflurane. During induction with a low dose of sevoflurane, beta/low gamma (12-40 Hz) power increased in the frontal EEG and PFC, PC and CT LFPs, and PFC-CT and PFC-PFC LFP beta/low gamma coherence increased...
2017: Frontiers in Neural Circuits
https://www.readbyqxmd.com/read/28724866/effect-of-reduced-tube-voltage-on-diagnostic-accuracy-of-ct-colonography
#16
Yoshihiro Futamata, Tomoaki Koide, Riku Ihara
The normal tube voltage in computed tomography colonography (CTC) is 120 kV. Some reports indicate that the use of a low tube voltage (lower than 120 kV) technique plays a significant role in reduction of radiation dose. However, to determine whether a lower tube voltage can reduce radiation dose without compromising diagnostic accuracy, an evaluation of images that are obtained while maintaining the volume CT dose index (CTDIvol) is required. This study investigated the effect of reduced tube voltage in CTC, without modifying radiation dose (i...
2017: Nihon Hoshasen Gijutsu Gakkai Zasshi
https://www.readbyqxmd.com/read/28724595/hypertensive-encephalopathy-mimicking-cerebral-vasculitis-with-pontine-oedema-cerebellar-white-matter-lesions-and-multiple-cerebral-infarctions
#17
Daniela Ceccarelli, David Hargroves, Ibrahim Balogun, Thomas Webb
A 47-year-old man with poorly controlled hypertension presented with headaches, right-sided weakness and dysarthria. CT and MRI scans of the brain showed widespread abnormalities including significant pontine oedema, basal ganglia and corona radiata infarctions and cerebellar white matter high signal. Imaging of the intracerebral vasculature also demonstrated wall irregularities. Initially a central nervous system inflammatory disorder was thought to be the most likely diagnosis, possibly acute demyelinating encephalomyelitis or cerebral vasculitis, and the patient was treated with high-dose intravenous steroids...
July 19, 2017: BMJ Case Reports
https://www.readbyqxmd.com/read/28724283/lung-cancer-screening-with-low-dose-ct-in-female-never-smokers-retrospective-cohort-study-with-long-term-national-data-follow-up
#18
Hyae Young Kim, Kyu-Won Jung, Kun Young Lim, Soo-Hyun Lee, Jae Kwan Jun, Jeongseon Kim, Bin Hwangbo, Jin Soo Lee
Purpose: Because of growing concerns about lung cancer in female never smokers, low-dose chest CT (LDCT) screening is often performed although it has never shown clinical benefits. We examine whether or not female never smokers really need annual LDCT screening when the initial LDCT showed negative findings. Materials and Methods: This retrospective cohort study included 4,365 female never smokers aged 40 to 79 years who performed initial LDCT from Aug 2002 to Dec 2007...
July 17, 2017: Cancer Research and Treatment: Official Journal of Korean Cancer Association
https://www.readbyqxmd.com/read/28723715/novel-weight-based-dose-threshold-for-18f-naf-pet-ct-imaging-using-advanced-pet-ct-systems-a-potential-tool-for-reducing-radiation-burden
#19
Fahad Marafi, Abdulreda Esmail, Rashid Rasheed, Fareeda Alkandari, Sharjeel Usmani
BACKGROUND: Fluorine-18-sodium fluoride (F-NaF) PET/CT is an important tool for detecting and evaluating metastatic bone cancer. Besides traditional dose metrics, recent methods such as real-time dose mapping, dose calculation from DICOM information, and their relevance to entrance skin exposure are currently in use to reduce the radiation burden. In this study, we have analyzed the data of 1062 patients retrospectively to evaluate patterns of absorbed dose for institutional weight-based dose protocol as compared with fixed dose method guidelines of Society of Nuclear Medicine and Molecular Imaging (SNMMI)...
July 18, 2017: Nuclear Medicine Communications
https://www.readbyqxmd.com/read/28722700/detection-of-bone-marrow-edema-pattern-with-dual-energy-computed-tomography-of-the-pig-mandible-treated-with-radiotherapy-and-surgery-compared-with-magnetic-resonance-imaging
#20
Lucas J Poort, Annika A R Stadler, Johan H B Ludlage, Frank J P Hoebers, Peter A W H Kessler, Alida A Postma
OBJECTIVE: The aim of the study was to investigate the accuracy of dual-energy computed tomography (DECT) compared with magnetic resonance (MR) imaging for the detection of edema of the mandible. MATERIALS AND METHODS: Fifteen adult Göttingen mini pigs received irradiation to the mandible with an equivalent dose of 0, 25, 50, or 70 Gy. Six months after irradiation, all animals underwent DECT and MR imaging of the mandible. Magnetic resonance short tau inversion recovery (STIR) was used for the grading of the bone marrow edema (0-3)...
July 2017: Journal of Computer Assisted Tomography
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