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https://www.readbyqxmd.com/read/28092637/non-invasive-classification-of-breast-microcalcifications-using-x-ray-coherent-scatter-computed-tomography
#1
Bahaa Ghammraoui, Lucretiu M Popescu
We investigate the use of energy dispersive x-ray coherent scatter computed tomography (ED-CSCT) as a non-invasive diagnostic method to differentiate between type I and type II breast calcifications. This approach is sensitive to the differences of composition and internal crystal structure of different types of microcalcifications. The study is carried out by simulating a CSCT system with a scanning pencil beam, considering a polychromatic x-ray source and an energy-resolving photon counting detector. In a first step, the multidimensional angle and energy distributed CSCT data is reduced to the projection-space distributions of only a few components, corresponding to the expected target composition: adipose, glandular tissue, weddellite (calcium oxalate) for type I calcifications, and hydroxyapatite for type II calcifications...
February 7, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28092630/comparative-monte-carlo-study-on-the-performance-of-integration-and-list-mode-detector-configurations-for-carbon-ion-computed-tomography
#2
Sebastian Meyer, Chiara Gianoli, Lorena Magallanes, Benedikt Kopp, Thomas Tessonnier, Guillaume Landry, George Dedes, Bernd Voss, Katia Parodi
Ion beam therapy offers the possibility of a highly conformal tumor-dose distribution; however, this technique is extremely sensitive to inaccuracies in the treatment procedures. Ambiguities in the conversion of Hounsfield units of the treatment planning x-ray CT to relative stopping power (RSP) can cause uncertainties in the estimated ion range of up to several millimeters. Ion CT (iCT) represents a favorable solution allowing to directly assess the RSP. In this simulation study we investigate the performance of the integration-mode configuration for carbon iCT, in comparison with a single-particle approach under the same set-up...
February 7, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28092526/estimation-of-basis-line-integrals-in-a-spectral-distortion-modeled-photon-counting-detector-using-low-order-polynomial-approximation-of-x-ray-transmittance
#3
Okkyun Lee, Steffen Kappler, Christoph Polster, Katsuyuki Taguchi
Photon counting detector (PCD)-based computed tomography exploits spectral information from a transmitted x-ray spectrum to estimate basis line-integrals. The recorded spectrum, however, is distorted and deviates from the transmitted spectrum due to spectral response effect (SRE). Therefore, the SRE needs to be compensated for when estimating basis lineintegrals. One approach is to incorporate the SRE model with an incident spectrum into the PCD measurement model and the other approach is to perform a calibration process that inherently includes both the SRE and the incident spectrum...
October 26, 2016: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/28092496/the-effect-of-contrast-material-on-radiation-dose-at-ct-part-i-incorporation-of-contrast-material-dynamics-in-anthropomorphic-phantoms
#4
Pooyan Sahbaee, W Paul Segars, Daniele Marin, Rendon C Nelson, Ehsan Samei
Purpose To develop a method to incorporate the propagation of contrast material into computational anthropomorphic phantoms for estimation of organ dose at computed tomography (CT). Materials and Methods A patient-specific physiologically based pharmacokinetic (PBPK) model of the human cardiovascular system was incorporated into 58 extended cardiac-torso (XCAT) patient phantoms. The PBPK model comprised compartmental models of vessels and organs unique to each XCAT model. For typical injection protocols, the dynamics of the contrast material in the body were described according to a series of patient-specific iodine mass-balance differential equations, the solutions to which provided the contrast material concentration time curves for each compartment...
January 13, 2017: Radiology
https://www.readbyqxmd.com/read/28092341/unilateral-spinous-process-non-covering-hook-type-patient-specific-drill-template-for-thoracic-pedicle-screw-fixation-a-pilot-clinical-trial-and-template-classification
#5
Sang Bum Kim, Yougun Won, Hyun Jin Yoo, Lee Jae Sin, John M Rhee, Sang Wook Lee, Gi-Soo Lee
STUDY DESIGN: Prospective Clinical Pilot tudy OBJECTIVE.: To confirm the accuracy of thoracic pedicle screw placement by using the unilateral spinous non-covering hook type patient-specific drill template (PSDT) made through rapid prototyping (RP) and to analyze previously reported PSDT designs and their characteristics. SUMMARY OF BACKGROUND DATA: Pedicle screw fixation is the most common form of the posterior instrumentation of the thoracic and lumbar spine. Various techniques have been introduced to improve pedicle screw placement...
January 13, 2017: Spine
https://www.readbyqxmd.com/read/28092312/synchronous-presentation-of-renal-cell-carcinoma-and-hodgkin-lymphoma-in-an-adolescent
#6
Mohamed Y Elsaid, Kara G Gill, Ankush Gosain, Peter F Nichol, Charles M Leys, Darya Buehler, Catherine P Leith, Neha J Patel
BACKGROUND: Coincidence of renal cell carcinoma (RCC) and hematologic malignancies has been reported in adults but not in children. OBSERVATION: We report a case of a 16-year-old girl in whom RCC was incidentally discovered on the computed tomography scan that was performed to stage her underlying Hodgkin lymphoma. Analysis of constitutional cytogenetics for common genetic aberrations that predispose to RCC did not reveal any mutations or genetic variations. However, cytogenetics on the RCC tumor demonstrated a rare reciprocal translocation between chromosomes 6 and 11, t(6;11)(p21;q12)...
January 13, 2017: Journal of Pediatric Hematology/oncology
https://www.readbyqxmd.com/read/28092136/computational-fluid-dynamic-modeling-of-nose-to-ceiling-head-positioning-for-sphenoid-sinus-irrigation
#7
John R Craig, James N Palmer, Kai Zhao
BACKGROUND: After sinus surgery, patients are commonly instructed to irrigate with saline irrigations with their heads over a sink and noses directed inferiorly (nose-to-floor). Although irrigations can penetrate the sinuses in this head position, no study has assessed whether sphenoid sinus penetration can be improved by irrigating with the nose directed superiorly (nose-to-ceiling). The purpose of this study was to use a validated computational fluid dynamics (CFD) model of sinus irrigations to assess the difference in sphenoid sinus delivery of irrigations after irrigating in a nose-to-floor vs nose-to-ceiling head position...
January 16, 2017: International Forum of Allergy & Rhinology
https://www.readbyqxmd.com/read/28092120/pediatric-peritonsillar-abscess-outcomes-and-cost-savings-from-using-transcervical-ultrasound
#8
Zhen Huang, William Vintzileos, Heather Gordish-Dressman, Anjum Bandarkar, Brian K Reilly
OBJECTIVES: 1) To analyze clinical outcomes of children stratified by ultrasound into three diagnoses: acute tonsillitis, peritonsillar phlegmon, and abscess; and 2) To compare clinical outcomes and financial impact between children who underwent ultrasound protocol to those who did not. STUDY DESIGN: Retrospective analysis between two cohorts: ultrasound protocol group and control group. METHODS: Children with peritonsillar abscess (PTA) diagnosed in the emergency department (ED) were enrolled during a 2-year period for transcervical ultrasound evaluation of bilateral tonsillar fossae...
January 16, 2017: Laryngoscope
https://www.readbyqxmd.com/read/28092118/incorporation-of-ct-based-measurements-of-trunk-anatomy-into-subject-specific-musculoskeletal-models-of-the-spine-influences-vertebral-loading-predictions
#9
Alexander G Bruno, Hossein Mokhtarzadeh, Brett T Allaire, Kelsey R Velie, M Clara De Paolis Kaluza, Dennis E Anderson, Mary L Bouxsein
We created subject-specific musculoskeletal models of the thoracolumbar spine by incorporating spine curvature and muscle morphology measurements from computed tomography (CT) scans to determine the degree to which vertebral compressive and shear loading estimates are sensitive to variations in trunk anatomy. We measured spine curvature and trunk muscle morphology using spine CT scans of 125 men, and then created four different thoracolumbar spine models for each person: 1) height and weight adjusted (Ht/Wt models); 2) height, weight and spine curvature adjusted (+C models); 3) height, weight and muscle morphology adjusted (+M models); and 4) height, weight, spine curvature, and muscle morphology adjusted (+CM models)...
January 16, 2017: Journal of Orthopaedic Research: Official Publication of the Orthopaedic Research Society
https://www.readbyqxmd.com/read/28092022/relevance-of-neuroimaging-for-neurocognitive-and-behavioral-outcome-after-pediatric-traumatic-brain-injury
#10
Marsh Königs, Petra Jw Pouwels, L W Ernest van Heurn, Roel Bakx, R Jeroen Vermeulen, J Carel Goslings, Bwee Tien Poll-The, Marleen van der Wees, Coriene E Catsman-Berrevoets, Jaap Oosterlaan
This study aims to (1) investigate the neuropathology of mild to severe pediatric TBI and (2) elucidate the predictive value of conventional and innovative neuroimaging for functional outcome. Children aged 8-14 years with trauma control (TC) injury (n = 27) were compared to children with mild TBI and risk factors for complicated TBI (mild(RF+), n = 20) or moderate/severe TBI (n = 17) at 2.8 years post-injury. Neuroimaging measures included: acute computed tomography (CT), volumetric analysis on post-acute conventional T1-weighted magnetic resonance imaging (MRI) and post-acute diffusion tensor imaging (DTI, analyzed using tract-based spatial statistics and voxel-wise regression)...
January 14, 2017: Brain Imaging and Behavior
https://www.readbyqxmd.com/read/28091969/quality-of-life-as-predictor-for-the-development-of-cardiac-ischemia-in-high-risk-asymptomatic-diabetic-patients
#11
Philip Haaf, Myriam Ritter, Leticia Grize, Matthias E Pfisterer, Michael J Zellweger
BACKGROUND: Ischemia induced by psychological stress and depression is a common phenomenon in stable coronary artery disease (CAD). We evaluated the quality of life (QoL) of diabetic patients screened for CAD and assessed the prognostic value of mental and physical QoL scores to predict the development of new cardiac ischemia. METHODS: Prospective multicentre outcome study. The study comprised 400 asymptomatic diabetic patients without history or symptoms of CAD...
January 13, 2017: Journal of Nuclear Cardiology: Official Publication of the American Society of Nuclear Cardiology
https://www.readbyqxmd.com/read/28091834/using-twitter-to-assess-the-public-response-to-the-united-states-preventive-services-task-force-guidelines-on-lung-cancer-screening-with-low-dose-chest-ct
#12
Siddharth Khasnavis, Andrew B Rosenkrantz, Vinay Prabhu
To use Twitter to assess the immediate public response to the United States Preventive Services Task Force (USPSTF) 2013 draft guidelines on lung cancer screening with low-dose chest CT (LDCT). The number of tweets including the phrases "lung cancer screening," "lung CT," "chest CT," "low dose computed tomography," "low dose CT," or "LDCT" was recorded for 6 days before and after guidelines release. A systematic sample of 172 tweets from the week following release was coded for user type, tweet opinion, linked article source, and article opinion...
January 13, 2017: Journal of Digital Imaging: the Official Journal of the Society for Computer Applications in Radiology
https://www.readbyqxmd.com/read/28091809/a-review-of-penetrating-brain-trauma-epidemiology-pathophysiology-imaging-assessment-complications-and-treatment
#13
REVIEW
Mona T Vakil, Ajay K Singh
Gunshot injuries are the most common cause of penetrating brain injury (PBI) and carry a high morbidity and mortality. The incidence of PBI has increased over the last decade with an estimated 35,000 civilian deaths annually. Patients that survive to reach the hospital require rapid triage and imaging evaluation. CT findings in conjunction with the Glasgow Coma Scale are typically used to determine which patients are surgical candidates. Radiologists should be familiar with the various injury patterns and imaging findings which are poor prognostic indicators, notably brainstem, bilateral hemispheric, multilobar, or transventricular injuries...
January 14, 2017: Emergency Radiology
https://www.readbyqxmd.com/read/28091793/attenuation-based-kv-pair-selection-in-dual-source-dual-energy-computed-tomography-angiography-of-the-chest-impact-on-radiation-dose-and-image-quality
#14
Rahul D Renapurkar, Andrew Primak, Joseph Azok, Jason Lempel, Yasmeen Tandon, Jennifer Bullen, Frank Dong, Wadih Karim, Ruffin Graham
OBJECTIVES: The purpose of this study was to evaluate the impact of attenuation-based kilovoltage (kV) pair selection in dual source dual energy (DSDE)-pulmonary embolism (PE) protocol examinations on radiation dose savings and image quality. METHODS: A prospective study was carried out on 118 patients with suspected PE. In patients in whom attenuation-based kV pair selection selected the 80/140Sn kV pair, the pre-scan 100/140Sn CTDIvol (computed tomography dose index volume) values were compared with the pre-scan 80/140Sn CTDIvol values...
January 13, 2017: European Radiology
https://www.readbyqxmd.com/read/28091724/automatic-ct-based-finite-element-model-generation-for-temperature-based-death-time-estimation-feasibility-study-and-sensitivity-analysis
#15
Sebastian Schenkl, Holger Muggenthaler, Michael Hubig, Bodo Erdmann, Martin Weiser, Stefan Zachow, Andreas Heinrich, Felix Victor Güttler, Ulf Teichgräber, Gita Mall
Temperature-based death time estimation is based either on simple phenomenological models of corpse cooling or on detailed physical heat transfer models. The latter are much more complex but allow a higher accuracy of death time estimation, as in principle, all relevant cooling mechanisms can be taken into account.Here, a complete workflow for finite element-based cooling simulation is presented. The following steps are demonstrated on a CT phantom: Computer tomography (CT) scan Segmentation of the CT images for thermodynamically relevant features of individual geometries and compilation in a geometric computer-aided design (CAD) model Conversion of the segmentation result into a finite element (FE) simulation model Computation of the model cooling curve (MOD) Calculation of the cooling time (CTE) For the first time in FE-based cooling time estimation, the steps from the CT image over segmentation to FE model generation are performed semi-automatically...
January 14, 2017: International Journal of Legal Medicine
https://www.readbyqxmd.com/read/28091700/computed-tomography-localization-of-the-appendix-in-the-pediatric-population-relative-to-the-lumbar-spine
#16
John Davis, Albert T Roh, Matthew B Petterson, Tammy R Kopelman, Samantha L Matz, Daniel G Gridley, Mary J Connell
BACKGROUND: Computed tomography (CT) is commonly used to evaluate suspected acute appendicitis. Although very effective, CT uses ionizing radiation, exposing patients to an increased risk of cancer. OBJECTIVE: This study assessed the potential for decreasing the field of view of the CT (and therefore the dose to the patient) in the evaluation of suspected acute appendicitis in children. MATERIALS AND METHODS: This study was a retrospective review of prospectively collected data from 212 consecutive patients who underwent CT for suspected acute appendicitis...
January 14, 2017: Pediatric Radiology
https://www.readbyqxmd.com/read/28091565/-18-f-flt-and-18-f-fdg-pet-ct-in-predicting-response-to-chemoradiotherapy-in-nasopharyngeal-carcinoma-preliminary-results
#17
Shi Qi, Yang Zhongyi, Zhang Yingjian, Hu Chaosu
The purpose of this study was to explore the feasibility of (18)F-Fluorothymidine ((18)F-FLT) and (18)F-Fluorodeoxyglucose ((18)F-FDG) positron emission tomography/computed tomography (PET/CT) in predicting treatment response of nasopharyngeal carcinoma (NPC). Patients with NPC of Stage II-IVB were prospectively enrolled, receiving 2 cycles of neoadjuvant chemotherapy (NACT), followed by concurrent chemoradiotherapy. Each patient underwent pretreatment and post-NACT FLT PET/CT and FDG PET/CT. Standard uptake values (SUV) and tumor volume were measured...
January 16, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28090791/additive-value-of-otosclerosis-weighted-images-for-the-ct-diagnosis-of-fenestral-otosclerosis
#18
Koji Yamashita, Akio Hiwatashi, Osamu Togao, Masatoshi Kondo, Kazufumi Kikuchi, Takashi Inoguchi, Junki Maehara, Yusuke Kyuragi, Hiroshi Honda
Background Otosclerotic foci are usually seen as minute low-density lesions and this may be attributed to relatively low sensitivity on visual assessment using computed tomography (CT). Otosclerotic foci can be detected by using the accurate region of interest (ROI) setting, while small ROI settings by less-experienced radiologists may result in false negative findings. Purpose To evaluate the diagnostic ability of our proposed method ("otosclerosis-weighted" imaging [OWI]), which is based on reversing the density, compared with conventional CT (CCT) imaging alone...
January 1, 2017: Acta Radiologica
https://www.readbyqxmd.com/read/28090758/bringing-clarity-or-confusion-the-role-of-prostate-specific-membrane-antigen-positron-emission-computed-tomography-for-primary-staging-in-prostate-cancer
#19
EDITORIAL
Declan G Murphy, Michael Hofman, Nathan Lawrentschuk, Tobias Maurer
No abstract text is available yet for this article.
February 2017: BJU International
https://www.readbyqxmd.com/read/28090452/classifying-thoracolumbar-fractures-role-of-quantitative-imaging
#20
REVIEW
Fernando Ruiz Santiago, Pablo Tomás Muñoz, Elena Moya Sánchez, Marta Revelles Paniza, Alberto Martínez Martínez, Antonio Luis Pérez Abela
This article describes different types of vertebral fractures that affect the thoracolumbar spine and the most relevant contributions of the different classification systems to vertebral fracture management. The vertebral fractures types are based on the three columns model of Denis that includes compression, burst, flexion-distraction and fracture-dislocation types. The most recent classifications systems of these types of fractures are reviewed, including the Thoracolumbar Injury Classification and Severity score (TLICS) and the Arbeitsgemeinschaft für Osteosynthesefragen Spine Thoracolumbar Injury Classification and Severity score (AOSpine-TLICS)...
December 2016: Quantitative Imaging in Medicine and Surgery
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