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CT imaging, increasing accuracy

Yan Wu, Yaojun Jiang, Xueli Han, Mingyue Wang, Jianbo Gao
Background: To investigate the repeatability and accuracy of quantitative CT (QCT) measurement of bone mineral density (BMD) by low-mAs using iterative model reconstruction (IMR) technique based on phantom model. Methods: European spine phantom (ESP) was selected and measured on the Philips Brilliance iCT Elite FHD machine for 10 times. Data were transmitted to the QCT PRO workstation to measure BMD (mg/cm3 ) of the ESP (L1, L2, L3). Scanning method: the voltage of X-ray tube is 120 kV, the electric current of X-ray tube output in five respective groups A-E were: 20, 30, 40, 50 and 60 mAs...
February 2018: Quantitative Imaging in Medicine and Surgery
D Yao, L Zhang, P L Wu, X L Gu, Y F Chen, L X Wang, X Y Huang
BACKGROUND: The primary pulmonary lymphoma (PPL), with a low incidence, was highly misdiagnosed in clinic. The present study analyzes the clinical features, laboratory and imaging data, pathologic characteristics, and summarizes misdiagnosis reasons of PPL cases, aims to provide a better understanding and increase the accuracy of early diagnosis and minimize the misdiagnosis of PPL. METHODS: The clinical data of 19 cases were collected from the first affiliated hospital of Wenzhou medical university (PRC) from April 2010 to May 2016...
March 12, 2018: BMC Cancer
Sinan Şen, Ralf Erber, Kevin Kunzmann, Stefanie Kirschner, Vanessa Weyer, Lothar Schilling, Marc A Brockmann, Stefan Rues, Gül Orhan, Christopher J Lux, Sebastian Zingler
OBJECTIVE: Optical coherence tomography (OCT) is a clinical standard in ophthalmology. Currently, its application in dentistry is gaining increasing interest. In this study, we tested the possibility to use a modified commercially available spectral domain OCT (SD-OCT) to assess the layer thickness of orthodontic surface sealants. MATERIALS AND METHODS: Reference samples of surface sealants for calibration and repeatability testing were measured using a micrometer screw...
March 9, 2018: Clinical Oral Investigations
José M Porcel
PURPOSE OF REVIEW: To provide an overview of the contribution of thoracic ultrasound (TUS) and computed tomography (CT) in the identification of complicated parapneumonic effusions (CPPE), defined as those which need chest tube drainage for resolution. RECENT FINDINGS: A recent retrospective study found that visualization of complex (nonanechoic) effusions on TUS (likelihood ratio positive = 6.92) outperformed the recognition of loculated/septated effusions on CT (likelihood ratio = 2...
March 6, 2018: Current Opinion in Pulmonary Medicine
Ellis Beld, Marinus A Moerland, Frank Zijlstra, Max A Viergever, Jan J W Lagendijk, Peter R Seevinck
For the purpose of MR-guided high-dose-rate (HDR) brachytherapy, a method for real-time localization of an HDR brachytherapy source was developed, which requires high spatial and temporal resolutions. MR-based localization of an HDR source serves two main aims. First, it enables real-time treatment verification by determination of the HDR source positions during treatment. Second, when using a dummy source, MR-based source localization provides an automatic detection of the source dwell positions after catheter insertion, allowing elimination of the catheter reconstruction procedure...
March 8, 2018: Physics in Medicine and Biology
Yunhe Xie, Christopher Ainsley, Lingshu Yin, Wei Zou, James McDonough, Timothy D Solberg, Alexander Lin, Boon-Keng Kevin Teo
A major source of uncertainty in proton therapy is the conversion of Hounsfield unit (HU) to proton stopping power ratio relative to water (SPR). In this study, we measured and quantified the accuracy of a stoichiometric dual energy CT (DECT) SPR calibration. We applied a stoichiometric DECT calibration method to derive the SPR using CT images acquired sequentially at [Formula: see text] and [Formula: see text]. The dual energy index was derived based on the HUs of the paired spectral images and used to calculate the effective atomic number (Zeff ), relative electron density ([Formula: see text]), and SPRs of phantom and biological materials...
March 7, 2018: Physics in Medicine and Biology
Sheng-Chieh Chan, Chih-Hua Yeh, Tzu-Chen Yen, Shu-Hang Ng, Joseph Tung-Chieh Chang, Chien-Yu Lin, Tsang Yen-Ming, Kang-Hsing Fan, Bing-Shen Huang, Cheng-Lung Hsu, Kai-Ping Chang, Hung-Ming Wang, Chun-Ta Liao
PURPOSE: Both head and neck magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) play a crucial role in the staging of primary nasopharyngeal carcinoma (NPC). In this study, we sought to prospectively investigate the clinical utility of simultaneous whole-body 18F-FDG PET/MRI for primary staging of NPC patients. METHODS: We examined 113 patients with histologically confirmed NPC who underwent pretreatment, simultaneous whole-body PET/MRI and PET/CT for primary tumor staging...
March 3, 2018: European Journal of Nuclear Medicine and Molecular Imaging
Hongsheng Jin, Zongyao Li, Ruofeng Tong, Lanfen Lin
PURPOSE: The automatic detection of pulmonary nodules using CT scans improves the efficiency of lung cancer diagnosis, and false positive reduction plays a significant role in the detection. In this paper, we focus on the false positive reduction task and propose an effective method for this task. METHODS: We construct a deep 3D residual CNN (convolution neural network) to reduce false positive nodules from candidate nodules. The proposed network is much deeper than the traditional 3D CNNs used in medical image processing...
March 3, 2018: Medical Physics
Gianluca Di Bella, Fausto Pizzino, Rocco Donato, Dalia Di Nunzio, Cesare de Gregorio
Cardiomyopathies (Cs) are a heterogeneous group of myocardial diseases with structural and/or functional abnormalities.The aetiology is due to genetic-family substrate in most cases, however, the correct and detailed analysis of morphofunctional abnormalities (severity and distribution of hypertrophy, ventricular dilatation, ventricular dysfunction) and tissue characteristics (myocardial fibrosis, myocardial infiltration) are a crucial element for a definite diagnosis.Among the different diagnostic imaging modalities applied in clinical practice (echocardiography, nuclear medicine), cardiac magnetic resonance (CMR) has emerged as a non-invasive diagnostic tool having high ability to quantify systolic function and tissue abnormalities that represent the substrates of many Cs...
March 2, 2018: Advances in Experimental Medicine and Biology
Farhoud Faraji, Stephanie F Coquia, Meghan B Wenderoth, Ericka S Padilla, Dana Blitz, M Robert DeJong, Nafi Aygun, Ulrike M Hamper, Carole Fakhry
OBJECTIVE: To compare transcervical ultrasonography (US) to standard cross-sectional imaging for the visualization of human papillomavirus-related oropharyngeal cancer (HPV-OPC). MATERIALS AND METHODS: Patients with HPV-OPC and available standard imaging (CT and/or MRI) were identified in clinic and prospectively enrolled. US was performed to visualize the oropharynx and lymph nodes. Tumor characteristics across imaging modalities were evaluated (CT versus MRI, and US versus standard imaging (SI))...
March 2018: Oral Oncology
Syed Muhammad Naqi, Muhammad Sharif, Mussarat Yasmin
PURPOSE: Lung cancer detection at its initial stages increases the survival chances of patients. Automatic detection of lung nodules facilitates radiologists during the diagnosis. However, there is a challenge of false positives in automated systems which may lead to wrong findings. Precise segmentation facilitates to accurately extract nodules from lung CT images in order to improve performance of the diagnostic method. METHODS: A multistage segmentation model is presented in this study...
February 28, 2018: International Journal of Computer Assisted Radiology and Surgery
Jei-Yie Huang, Ruoh-Fang Yen, Wen-Chung Lee, Chun-Kai Huang, Pei-Ying Hsu, Mei-Fang Cheng, Ching-Chu Lu, Yen-Hung Lin, Kuo-Liong Chien, Yen-Wen Wu
BACKGROUND: The benefits of attenuation correction (AC) in technetium-99m myocardial perfusion imaging (MPI) have been well established. However, the value of thallium (Tl-201) AC and routine computed tomography AC (CTAC) were less well established. The aims of this study were to evaluate the diagnostic performance of thallium (Tl-201) MPI with additional CTAC and to determine which participants would benefit most. METHODS AND RESULTS: A total of 108 consecutive patients who underwent Tl-201 MPI and received coronary angiography within 3 months were enrolled...
February 26, 2018: Journal of Nuclear Cardiology: Official Publication of the American Society of Nuclear Cardiology
Giorgia M Bosi, Claudio Capelli, Mun Hong Cheang, Nicola Delahunty, Michael Mullen, Andrew M Taylor, Silvia Schievano
Patient-specific computational models are an established tool to support device development and test under clinically relevant boundary conditions. Potentially, such models could be used to aid the clinical decision-making process for percutaneous valve selection; however, their adoption in clinical practice is still limited to individual cases. To be fully informative, they should include patient-specific data on both anatomy and mechanics of the implantation site. In this work, fourteen patient-specific computational models for transcatheter aortic valve replacement (TAVR) with balloon-expandable Sapien XT devices were retrospectively developed to tune the material parameters of the implantation site mechanical model for the average TAVR population...
February 20, 2018: Journal of Biomechanics
Najeeb Ahmed, Kashif Niyaz, Aditya Borakati, Fahad Marafi, Rubinder Birk, Sharjeel Usmani
Differentiated thyroid cancer (DTC) has a good prognosis overall; however, lifelong follow-up is required for many cases. Radioiodine planar imaging with iodine-123 (I-123) or radioiodine-131 (I-131) remains the standard in the follow-up after initial surgery and ablation of residual thyroid tissue using I-131 therapy. Radioiodine imaging is also used in risk-stratifying and for staging of thyroid cancer, and in long-term follow-up. Unfortunately, the lack of anatomical detail on planar gamma camera imaging and superimposition of areas presenting with increased radioiodine uptake can make accurate diagnosis and localization of radioiodine-avid metastatic disease challenging, leading to false positive results and potentially to over-treatment of patients...
February 26, 2018: Asian Pacific Journal of Cancer Prevention: APJCP
Miroslav Jiřík, Martin Bartoš, Petr Tomášek, Anna Malečková, Tomáš Kural, Jana Horáková, David Lukáš, Tomáš Suchý, Petra Kochová, Marie Hubálek Kalbáčová, Milena Králíčková, Zbyněk Tonar
Quantification of the structure and composition of biomaterials using micro-CT requires image segmentation due to the low contrast and overlapping radioopacity of biological materials. The amount of bias introduced by segmentation procedures is generally unknown. We aim to develop software that generates three-dimensional models of fibrous and porous structures with known volumes, surfaces, lengths, and object counts in fibrous materials and to provide a software tool that calibrates quantitative micro-CT assessments...
February 24, 2018: Microscopy Research and Technique
Ivo M Wagensveld, Britt M Blokker, Andrea Pezzato, Piotr A Wielopolski, Nomdo S Renken, Jan H von der Thüsen, Gabriel P Krestin, M G Myriam Hunink, J Wolter Oosterhuis, Annick C Weustink
Aims: The autopsy rate worldwide is alarmingly low (0-15%). Mortality statistics are important, and it is, therefore, essential to perform autopsies in a sufficient proportion of deaths. The imaging autopsy, non-invasive, or minimally invasive autopsy (MIA) can be used as an alternative to the conventional autopsy in an attempt to improve postmortem diagnostics by increasing the number of postmortem procedures. The aim of this study was to determine the diagnostic accuracy of postmortem magnetic resonance imaging (MRI), computed tomography (CT), and CT-guided biopsy for the detection of acute and chronic myocardial ischaemia...
February 20, 2018: European Heart Journal Cardiovascular Imaging
Christoph Schabel, Bhavik Patel, Scott Harring, Petar Duvnjak, Juan Carlos Ramírez-Giraldo, Konstantin Nikolaou, Rendon C Nelson, Alfredo E Farjat, Daniele Marin
Purpose To investigate the relationship between energy level of virtual monoenergetic (VM) imaging and sensitivity in the detection of minimally enhancing renal lesions. Materials and Methods Phantoms simulating unenhanced and contrast material-enhanced renal parenchyma were equipped with inserts containing different concentrations of iodine (range, 0-1.15 mg iodine per milliliter). A total of 180 patients (117 men; mean age, 65.2 years ± 13.0 [standard deviation]) with 194 (62 solid, 132 cystic) renal lesions larger than 10 mm in diameter underwent unenhanced single-energy CT and contrast-enhanced dual-energy CT...
February 22, 2018: Radiology
Inês Pita, Fernando Magro
Treatment of Crohn's disease (CD) is intrinsically reliant on imaging techniques, due to the preponderance of small bowel disease and its transmural pattern of inflammation. Ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI) are the most widely employed imaging methods and have excellent diagnostic accuracy in most instances. Some limitations persist, perhaps the most clinically relevant being the distinction between inflammatory and fibrotic strictures. In this regard, several methodologies have recently been tested in animal models and human patients, namely US strain elastography, shear wave elastography, contrast-enhanced US, magnetization transfer MRI and contrast dynamics in standard MRI...
2018: Therapeutic Advances in Gastroenterology
Andrew J Kobets, Adam Ammar, Jonathan Nakhla, Aleka Scoco, Rani Nasser, James T Goodrich, Rick Abbott
INTRODUCTION: Sagittal synostosis affects 1 in 1000 live births and may result in increased intracranial pressure, hindrance of normal neural development, and cosmetic deformity due to scaphocephaly. Historically, several approaches have been utilized for surgical correction and recently, computed tomography (CT)-guided reconstruction procedures are increasingly used. In this report, the authors describe the use of a CT-derived virtual and stereolithographic (3D printed) craniofacial models, which are used to guide intraoperative bone placement, and intraoperative CT guidance for confirmation of bone placement, to ensure the accuracy of surgical correction of scaphocephaly, as demonstrated to parents...
February 19, 2018: Child's Nervous System: ChNS: Official Journal of the International Society for Pediatric Neurosurgery
Tima Davidson, Eldar Priel, Ginette Schiby, Stephen Raskin, Bar Chikman, Ella Nissan, Ohad Benjamini, Johnatan Nissan, Elinor Goshen, Simona Ben-Haim, Ophira Salomon, Abraham Avigdor
BACKGROUND: Burkitt lymphoma is a highly aggressive B cell non-Hodgkin lymphoma. Cross-sectional imaging techniques that are used to detect liver and spleen involvement by lymphoma have high rates of false negative and false positive findings, and as such may reduce the accuracy of staging. PURPOSE: This retrospective study evaluated the use of FDG PET-CT in determining splenic involvement at staging, in a relatively large cohort of adult patients with the sporadic form of Burkitt lymphoma (SBL)...
February 19, 2018: Abdominal Radiology
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