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https://www.readbyqxmd.com/read/27912764/sbrt-for-centrally-localized-nsclc-what-is-too-central
#1
J Roesch, C Panje, F Sterzing, F Mantel, U Nestle, N Andratschke, M Guckenberger
PURPOSE: Current guidelines recommend stereotactic body radiotherapy (SBRT) for stage I non-small-cell lung cancer (NSCLC) in medically inoperable patients. There are excellent outcome and toxicity data for SBRT of peripheral lung tumors. However, the discussion on SBRT for centrally located tumors is controversial. This study evaluated current clinical practice regarding SBRT of centrally located lung tumors, to identify common fractionation schedules and commonly accepted contraindications for SBRT...
December 3, 2016: Radiation Oncology
https://www.readbyqxmd.com/read/27911354/a-spectral-interior-ct-by-a-framelet-based-reconstruction-algorithm
#2
Yingmei Wang, Ge Wang, Shuwei Mao, Wenxiang Cong, Zhilong Ji, Jian-Feng Cai, Yangbo Ye
Reducing radiation dose is an important goal in medical computed tomography (CT), for which interior tomography is an effective approach. There have been interior reconstruction algorithms for monochromatic CT, but in reality, X-ray sources are polychromatic. Using a polychromatic acquisition model and motivated by framelet-based image processing algorithms, in this paper, we propose an interior reconstruction algorithm to obtain an image with spectral information assuming only one scan with a current energy-integrating detector...
November 22, 2016: Journal of X-ray Science and Technology
https://www.readbyqxmd.com/read/27910717/dose-optimisation-for-assessment-of-periodontal-structures-in-cone-beam-ct-examinations
#3
Ayman Al-Okshi, Chrysoula Theodorakou, Christina Lindh
OBJECTIVE: To investigate the relationship between dose and image quality for a dedicated dental Cone Beam CT (CBCT) scanner using different scanning protocols and to set up an optimal imaging protocol for assessment of periodontal structures. METHODS: Radiation dose and image quality measurements were made using the 3D Accuitomo 170 dental CBCT scanner. The SedentexCT IQ phantom was used to investigate the relationship between contrast-to-noise ratio (CNR) and dose-area product (DAP)...
December 2, 2016: Dento Maxillo Facial Radiology
https://www.readbyqxmd.com/read/27909929/signal-to-noise-ratio-and-dose-to-the-lens-of-the-eye-for-computed-tomography-examination-of-the-brain-using-an-automatic-tube-current-modulation-system
#4
Supawitoo Sookpeng, Chitsanupong Butdee
PURPOSE: The study aimed to evaluate the image quality in terms of signal-to-noise ratio (SNR) and dose to the lens of the eye and the other nearby organs from the CT brain scan using an automatic tube current modulation (ATCM) system with or without CT gantry tilt is needed. METHODS: An anthropomorphic phantom was scanned with different settings including use of different ATCM, fixed tube current time product (mAs) settings and degree angles of gantry tilt. Gafchromic film XR-QA2 was used to measure absorbed dose of the organs...
December 2, 2016: Emergency Radiology
https://www.readbyqxmd.com/read/27909787/test-retest-reliability-of-tibiofemoral-joint-space-width-measurements-made-using-a-low-dose-standing-ct-scanner
#5
Neil A Segal, John Bergin, Andrew Kern, Christian Findlay, Donald D Anderson
OBJECTIVE: To determine the test-retest reliability of knee joint space width (JSW) measurements made using standing CT (SCT) imaging. SUBJECTS AND METHODS: This prospective two-visit study included 50 knees from 30 subjects (66% female; mean ± SD age 58.2 ± 11.3 years; BMI 29.1 ± 5.6 kg/m(2); 38% KL grade 0-1). Tibiofemoral geometry was obtained from bilateral, approximately 20° fixed-flexed SCT images acquired at visits 2 weeks apart. For each compartment, the total joint area was defined as the area with a JSW <10 mm...
December 1, 2016: Skeletal Radiology
https://www.readbyqxmd.com/read/27909130/the-use-of-ultra-low-dose-ct-scans-for-the-evaluation-of-limb-fractures-is-the-reduced-effective-dose-using-ct-in-orthopaedic-injury-reduction-protocol-effective
#6
S R Konda, A M Goch, P Leucht, A Christiano, S Gyftopoulos, G Yoeli, K A Egol
AIMS: To evaluate whether an ultra-low-dose CT protocol can diagnose selected limb fractures as well as conventional CT (C-CT). PATIENTS AND METHODS: We prospectively studied 40 consecutive patients with a limb fracture in whom a CT scan was indicated. These were scanned using an ultra-low-dose CT Reduced Effective Dose Using Computed Tomography In Orthopaedic Injury (REDUCTION) protocol. Studies from 16 selected cases were compared with 16 C-CT scans matched for age, gender and type of fracture...
December 2016: Bone & Joint Journal
https://www.readbyqxmd.com/read/27908971/13n-ammonia-pet-ct-detection-of-myocardial-perfusion-abnormalities-in-beagle-dogs-after-local-heart-irradiation
#7
Jianbo Song, Rui Yan, Zhifang Wu, Jianguo Li, Min Yan, Xinzhong Hao, Jianzhong Liu, Sijin Li
: To determine the potential value of (13)N-ammonia positron emission tomography (PET)/computed tomography (CT) myocardial perfusion imaging (MPI) for detection of myocardial perfusion changes at early stage induced by radiation damage. METHODS: Thirty-six Beagle dogs were randomly divided into the control (n = 18) or the irradiation groups (n = 18). The irradiation group underwent local irradiation to the left ventricular anterior cardiac wall with a single dose of 20 Gy, whereas the control group received sham irradiation...
December 1, 2016: Journal of Nuclear Medicine: Official Publication, Society of Nuclear Medicine
https://www.readbyqxmd.com/read/27908678/avoidance-of-late-rectal-toxicity-after-high-dose-rate-brachytherapy-boost-treatment-for-prostate-cancer
#8
Borut Kragelj, Jernej Zlatic, Lijana Zaletel-Kragelj
PURPOSE: To elucidate potential risk factors important for the appearance of late rectal toxicity (LRT) after high-dose-rate boost treatment (HDRBT) of prostate cancer and to validate the predictive value of the minimal dose to the most exposed 2 cc of rectum received with HDRBT (D2ccrect). METHODS AND MATERIALS: The study of LRT, defined as relative deterioration of defecation problems (RDDP) (stool frequency, pain, rectal bleeding, fecal urgency, and incontinence) during follow-up period, was carried out on 88 patients, consecutively treated from October 2006 through April 2011 with HDRBT of 3 × 6-7 Gy to 50-50...
November 28, 2016: Brachytherapy
https://www.readbyqxmd.com/read/27908187/dosimetric-characterization-of-mri-only-treatment-planning-for-brain-tumors-in-atlas-based-pseudo-ct-images-generated-from-standard-t1-weighted-mr-images
#9
Benjamin Demol, Christine Boydev, Juha Korhonen, Nick Reynaert
PURPOSE: Magnetic resonance imaging (MRI)-only radiotherapy treatment planning requires accurate pseudo-CT (pCT) images for precise dose calculation. The current work introduced an atlas-based method combined with MR intensity information. pCT analyses and Monte Carlo dose calculations for intracranial stereotactic treatments were performed. METHODS: Twenty-two patients, representing 35 tumor targets, were scanned using a 3D T1-weighted MRI sequence according to the clinical protocol...
December 2016: Medical Physics
https://www.readbyqxmd.com/read/27908164/comparison-of-low-contrast-detectability-between-two-ct-reconstruction-algorithms-using-voxel-based-3d-printed-textured-phantoms
#10
Justin Solomon, Alexandre Ba, François Bochud, Ehsan Samei
PURPOSE: To use novel voxel-based 3D printed textured phantoms in order to compare low-contrast detectability between two reconstruction algorithms, FBP (filtered-backprojection) and SAFIRE (sinogram affirmed iterative reconstruction) and determine what impact background texture (i.e., anatomical noise) has on estimating the dose reduction potential of SAFIRE. METHODS: Liver volumes were segmented from 23 abdominal CT cases. The volumes were characterized in terms of texture features from gray-level co-occurrence and run-length matrices...
December 2016: Medical Physics
https://www.readbyqxmd.com/read/27908157/volumetry-of-low-contrast-liver-lesions-with-ct-investigation-of-estimation-uncertainties-in-a-phantom-study
#11
Qin Li, Yongguang Liang, Qiao Huang, Min Zong, Benjamin Berman, Marios A Gavrielides, Lawrence H Schwartz, Binsheng Zhao, Nicholas Petrick
PURPOSE: To evaluate the performance of lesion volumetry in hepatic CT as a function of various imaging acquisition parameters. METHODS: An anthropomorphic abdominal phantom with removable liver inserts was designed for this study. Two liver inserts, each containing 19 synthetic lesions with varying diameter (6-40 mm), shape, contrast (10-65 HU), and both homogenous and mixed-density were designed to have background and lesion CT values corresponding to arterial and portal-venous phase imaging, respectively...
December 2016: Medical Physics
https://www.readbyqxmd.com/read/27908151/technical-note-a-direct-ray-tracing-method-to-compute-integral-depth-dose-in-pencil-beam-proton-radiography-with-a-multilayer-ionization-chamber
#12
Paolo Farace, Roberto Righetto, Sylvain Deffet, Arturs Meijers, Francois Vander Stappen
PURPOSE: To introduce a fast ray-tracing algorithm in pencil proton radiography (PR) with a multilayer ionization chamber (MLIC) for in vivo range error mapping. METHODS: Pencil beam PR was obtained by delivering spots uniformly positioned in a square (45 × 45 mm(2) field-of-view) of 9 × 9 spots capable of crossing the phantoms (210 MeV). The exit beam was collected by a MLIC to sample the integral depth dose (IDDMLIC). PRs of an electron-density and of a head phantom were acquired by moving the couch to obtain multiple 45 × 45 mm(2) frames...
December 2016: Medical Physics
https://www.readbyqxmd.com/read/27908148/local-attenuation-curve-optimization-framework-for-high-quality-perfusion-maps-in-low-dose-cerebral-perfusion-ct
#13
Vincent Van Nieuwenhove, Geert Van Eyndhoven, K Joost Batenburg, Nico Buls, Jef Vandemeulebroucke, Jan De Beenhouwer, Jan Sijbers
PURPOSE: Cerebral perfusion x-ray computed tomography (PCT) is a powerful tool for noninvasive imaging of hemodynamic information throughout the brain. Conventional PCT requires the brain to be imaged multiple times during the perfusion process, and hence radiation dose is a major concern. The authors propose a PCT reconstruction algorithm that allows for lowering the dose while maintaining a high quality of the perfusion maps. It relies on an accurate estimation of the arterial input function (AIF), which in turn depends on the quality of the attenuation curves in the arterial region...
December 2016: Medical Physics
https://www.readbyqxmd.com/read/27908147/strategies-for-ct-tissue-segmentation-for-monte-carlo-calculations-in-nuclear-medicine-dosimetry
#14
P E N Braad, T Andersen, S B Hansen, P F Høilund-Carlsen
PURPOSE: CT images are used for patient specific Monte Carlo treatment planning in radionuclide therapy. The authors investigated the impact of tissue classification, CT image segmentation, and CT errors on Monte Carlo calculated absorbed dose estimates in nuclear medicine. METHODS: CT errors as a function of patient size, CT reconstruction, and tube current modulation methods were assessed in a phantom experiment on a clinical CT system. The impact of tissue segmentation methods and CT number variations on EGSnrc Monte Carlo calculated absorbed dose distributions was assessed for (99m)Tc and (131)I in the ICRP/ICRU male phantom and in a patient PET/CT-scanned with (124)I prior to radioiodine therapy...
December 2016: Medical Physics
https://www.readbyqxmd.com/read/27907049/dual-energy-ct-pulmonary-angiography-with-6g-iodine-a-propensity-score-matched-study
#15
Andreas Meier, Kai Higashigaito, Katharina Martini, Moritz Wurnig, Burkhardt Seifert, Dagmar Keller, Thomas Frauenfelder, Hatem Alkadhi
OBJECTIVE: To evaluate the performance of low contrast media (CM) dose dual-energy computed tomography pulmonary angiography (CTPA) with advanced monoenergetic reconstructions in patients with suspected pulmonary embolism (PE). MATERIALS AND METHODS: The study had institutional review board approval; all patients gave written informed consent. Forty-one patients (25 men, 16 women, mean age 62.9±14.7 years) undergoing low CM dose (15ml, 6g iodine) dual-energy CTPA with advanced monoenergetic reconstructions were matched via propensity-scoring based on logistic regression analysis with a comparison group of 41 patients (24 men, 17 women, mean age 62...
2016: PloS One
https://www.readbyqxmd.com/read/27907047/rage-deficiency-impairs-bacterial-clearance-in-murine-staphylococcal-sepsis-but-has-no-significant-impact-on-staphylococcal-septic-arthritis
#16
Majd Mohammad, Manli Na, Amanda Welin, Mattias N D Svensson, Abukar Ali, Tao Jin, Rille Pullerits
BACKGROUND: Septic arthritis is a serious joint disease often caused by Staphylococcus aureus (S. aureus). Receptor for Advanced Glycation End products (RAGE) has an important role in several infections. We sought to investigate the role of RAGE in staphylococcal septic arthritis and sepsis in mice. METHODS: Wild-type (WT) and RAGE deficient (RAGE-/-) mice were intra-articularly or intravenously inoculated with an arthritic or septic dose of S. aureus LS-1 strain...
2016: PloS One
https://www.readbyqxmd.com/read/27906944/the-safety-of-ct-guided-epidural-steroid-injections-in-an-older-patient-cohort
#17
Andrew J Fenster, Kevin Fernandes, Alan L Brook, Todd Miller
BACKGROUND: Epidural steroid injections (ESIs) are a common method for treating lower back pain, which is one of the most prevalent health-related complaints in the adult US population. Although the safety of CT-guided ESIs has been extensively studied in adults, there is limited data concerning the procedure's safety profile in an older patient population. OBJECTIVE: This retrospective study analyzed safety data among a single-center cohort of patients > 65 years-old who received one or more CT-guided interlaminar ESIs from 2012 to 2015...
November 2016: Pain Physician
https://www.readbyqxmd.com/read/27904902/a-novel-hirudin-derivative-inhibiting-thrombin-without-bleeding-for-subcutaneous-injection
#18
Bing Zhao, Yanling Zhang, Yinong Huang, Jinchao Yu, Yaran Li, Qi Wang, Yixin Ma, Hou-Yan Song, Min Yu, Wei Mo
Currently, anticoagulants would be used to prevent thrombosis. Thrombin is an effector enzyme for haemostasis and thrombosis. We designed a direct thrombin inhibitor peptide (DTIP) using molecular simulation and homology modelling and demonstrated that the C-terminus of DTIP interacts with exosite I, and N-terminus with the activity site of thrombin, respectively. DTIP interfered with thrombin-mediated coagulation in human, rat and mouse plasma (n=10 per group) and blocked clotting in human whole blood in vitro...
December 1, 2016: Thrombosis and Haemostasis
https://www.readbyqxmd.com/read/27904442/granulomatosis-after-autologous-stem-cell-transplantation-in-nonhodgkin-lymphoma-experience-of-single-institution-and-a-review-of-literature
#19
Lucka Boltezar, Ivana Zagar, Barbara Jezersek Novakovic
BACKGROUND: Sarcoidosis before and after treatment of malignancy is an important differential diagnosis that has to be distinguished from lymphoma. PATIENTS AND METHODS: Hodgkin lymphoma, diffuse large B-cell lymphoma and aggressive follicular lymphoma are being staged and treatment effect is evaluated with PET-CT. We report three cases of aggressive lymphoma after high dose therapy and autologous stem cell transplantation with positive lymph nodes on PET-CT, which were histologically diagnosed as sarcoidosis/granulomatosis...
December 1, 2016: Radiology and Oncology
https://www.readbyqxmd.com/read/27904047/protective-effect-of-deer-bone-oil-on-cartilage-destruction-in-rats-with-monosodium-iodoacetate-mia-induced-osteoarthritis
#20
Hyeon-Son Choi, Suji Im, Je Won Park, Hyung Joo Suh
The anti-osteoarthritic activity of the methanol fraction of deer bone oil extract (DBO-M) was evaluated in interleukin (IL)-1β-inflamed primary rabbit chondrocytes and in rats with monosodium iodoacetate (MIA)-induced osteoarthritis. The active compound in DBO-M was analyzed using a direct infusion liquid chromatography quadrupole (LCQ) ion-trap electrospray ionization (ESI)-mass spectrometer (MS). DBO-M significantly suppressed the IL-1β-induced sulfated-glycosaminoglycan (s-GAG) release from chondrocyte, and lowered mRNA levels of the collagen-degrading enzymes matrix metalloproteinase (MMP)-1 and MMP-3 in a dose-dependent manner...
2016: Biological & Pharmaceutical Bulletin
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