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Hounsfield Units (HU)

Benjamin Wildman-Tobriner, Michael S Enslow, Rendon C Nelson
OBJECTIVE: When objectively measured on computed tomography (CT), does hepatic heterogeneity or overall liver attenuation predict the presence of shock? METHODS: This retrospective study included 73 patients (mean age 33 years) with the hypoperfusion shock complex (HSC) on CT (cases) and 100 patients (mean age 43 years) with negative trauma CT scans (controls). Liver heterogeneity was calculated by using consistently sized regions of interest (ROIs) to measure the 2 highest and the 2 lowest areas of hepatic density (in Hounsfield units [HU])...
February 10, 2018: Current Problems in Diagnostic Radiology
Robyn Melanie Benz, Meritxell Alzamora Garcia, Felix Amsler, Johannes Voigt, Andreas Fieselmann, Anna Lucja Falkowski, Bram Stieltjes, Anna Hirschmann
Phantom-based initial performance assessment of a prototype three-dimensional (3-D) x-ray system and comparison of 3-D tomography with computed tomography (CT) were proposed. A 3-D image quality phantom was scanned with a prototype version of 3-D cone-beam CT imaging implemented on a twin robotic x-ray system using three trajectories (163 deg = table, 188 deg = upright, and 200 deg = side), six tube voltages (60, 70, 81, 90, 100, and 121 kV), and four detector doses (0.348, 0.696, 1.740, and [Formula: see text])...
January 2018: Journal of Medical Imaging
Antonio Esposito, Anna Palmisano, Sofia Antunes, Caterina Colantoni, Paola Maria Vittoria Rancoita, Davide Vignale, Francesca Baratto, Paolo Della Bella, Alessandro Del Maschio, Francesco De Cobelli
PURPOSE: Diffuse remodeling of myocardial extra-cellular matrix is largely responsible for left ventricle (LV) dysfunction and arrhythmias. Our hypothesis is that the texture analysis of late iodine enhancement (LIE) cardiac computed tomography (cCT) images may improve characterization of the diffuse extra-cellular matrix changes. Our aim was to extract volumetric extracellular volume (ECV) and LIE texture features of non-scarred (remote) myocardium from cCT of patients with recurrent ventricular tachycardia (rVT), and to compare these radiomic features with LV-function, LV-remodeling, and underlying cardiac disease...
March 13, 2018: Molecular Imaging and Biology: MIB: the Official Publication of the Academy of Molecular Imaging
Andrew J Benjamin, Mary M Buschmann, Shuang Qin Zhang, Kristen Wroblewski, Hedy L Kindler, Kevin K Roggin, William Dale
OBJECTIVE: Sarcopenia is associated with poor outcomes in patients undergoing surgery for pancreatic ductal adenocarcinoma (PDAC). However, few studies have assessed changes in sarcopenia during multimodality therapy or its effect on overall survival (OS). METHODS: Computed tomography (CT) total psoas area index (TPAI) and weighted average Hounsfield units (HU) were measured at each treatment interval in patients with resectable PDAC. Four cohorts were compared: 1...
March 10, 2018: Journal of Geriatric Oncology
Achmed Pircher, Margherita Montali, Peter Wostyn, Joachim Pircher, Jatta Berberat, Luca Remonda, Hanspeter E Killer
PURPOSE: To investigate the cerebrospinal fluid (CSF) dynamics along the entire optic nerve (ON) in patients with normal-tension glaucoma (NTG). METHODS: Retrospective analysis of computed tomographic (CT) cisternographies in Caucasian patients with NTG. Fifty-six patients (99 of 112 eyes) fulfilled the diagnostic criteria of NTG and underwent CT-cisternography. Twelve subjects without NTG (24 eyes) served as controls. Contrast-loaded cerebrospinal fluid (CLCSF) density measurements in Hounsfield units (HU) were performed at four defined regions along the ON and in the basal cistern...
March 12, 2018: Acta Ophthalmologica
Olivier van Wulfften Palthe, Kyung-Wook Jee, Jos A M Bramer, Francis J Hornicek, Yen-Lin E Chen, Joseph H Schwab
BACKGROUND: Effects of high-dose radiation using protons and photons on bone are relatively unexplored, but high rates of insufficiency fractures are reported, and the causes of this are incompletely understood. Imaging studies with pre- and postradiation scans can help one understand the effect of radiation on bone. QUESTIONS/PURPOSES: The purpose of this study was to assess the effects of high-dose radiation on the trabecular density of bone in the sacrum using CT-derived Hounsfield units (HU)...
March 2018: Clinical Orthopaedics and related Research
D Rebello, D Anjelly, D J Grand, J T Machan, M D Beland, M S Furman, J Shapiro, N LeLeiko, B E Sands, M Mallette, R Bright, H Moniz, M Merrick, S A Shah
Bone disease is prevalent among patients with inflammatory bowel disease (IBD), though bone density screening remains underutilized. We used CT scans performed for other indications in IBD patients to identify and monitor osteopenia using CT attenuation values at the lumbar spine. Significant rates of bone disease were detected which would have otherwise gone undiagnosed. INTRODUCTION: Osteoporosis affects about 14-42% of patients with IBD. Though screening is recommended in IBD patients with risk factors, it remains underutilized...
March 8, 2018: Osteoporosis International
Qian Wu, Mengmeng Yu, Yuehua Li, Wenbin Li, Zhigang Lu, Meng Wei, Jing Yan, Jiayin Zhang
Objective: To investigate the morphological changes of coronary chronic total occlusion (CTO) as determined by coronary computed tomography angiography (CCTA) follow-up using semi-automated quantitative analysis. Materials and Methods: Thirty patients with 31 CTO lesions confirmed by invasive coronary angiography and baseline/follow-up CCTA were retrospectively included. CTOs were quantitatively analyzed by a semi-automated coronary plaque analysis software (Coronary Plaque Analysis, version 2...
March 2018: Korean Journal of Radiology: Official Journal of the Korean Radiological Society
Mingxing Yang, Maxie Kohler, Tina Heyder, Helena Forsslund, Hilde K Garberg, Reza Karimi, Johan Grunewald, Frode S Berven, Sven Nyrén, C Magnus Sköld, Åsa M Wheelock
BACKGROUND: Smoking is the main risk factor for chronic obstructive pulmonary disease (COPD). Women with COPD who smoke experienced a higher risk of hospitalization and worse decline of lung function. Yet the mechanisms of these gender-related differences in clinical presentations in COPD remain unknown. The aim of our study is to identify proteins and molecular pathways associated with COPD pathogenesis, with emphasis on elucidating molecular gender difference. METHOD: We employed shotgun isobaric tags for relative and absolute quantitation (iTRAQ) proteome analyses of bronchoalveolar lavage (BAL) cells from smokers with normal lung function (n = 25) and early stage COPD patients (n = 18)...
March 8, 2018: Respiratory Research
Kyle Edmunds, Magnús Gíslason, Sigurður Sigurðsson, Vilmundur Guðnason, Tamara Harris, Ugo Carraro, Paolo Gargiulo
Sarcopenic muscular degeneration has been consistently identified as an independent risk factor for mortality in aging populations. Recent investigations have realized the quantitative potential of computed tomography (CT) image analysis to describe skeletal muscle volume and composition; however, the optimum approach to assessing these data remains debated. Current literature reports average Hounsfield unit (HU) values and/or segmented soft tissue cross-sectional areas to investigate muscle quality. However, standardized methods for CT analyses and their utility as a comorbidity index remain undefined, and no existing studies compare these methods to the assessment of entire radiodensitometric distributions...
2018: PloS One
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
Florieke Eggermont, Loes Derikx, Jeffrey Free, Ruud van Leeuwen, Yvette van der Linden, Nico Verdonschot, Esther Tanck
In a multi-center patient study, using different CT scanners, CT-based finite element (FE) models are utilized to calculate failure loads of femora with metastases. Previous studies showed that using different CT scanners can result in different outcomes. This study aims to quantify the effects of 1) different CT scanners, 2) different CT protocols with variations in slice thickness, field of view (FOV) and reconstruction kernel, and 3) air between calibration phantom and patient, on Hounsfield Units (HU), bone mineral density (BMD) and FE failure load...
March 6, 2018: Journal of Orthopaedic Research: Official Publication of the Orthopaedic Research Society
Kwang Suk Lee, Kyo Chul Koo, Byung Ha Chung
PURPOSE: Hypoechoic lesions are not included as indicators for prostate biopsy. To discriminate the features of hypoechoic lesions, we investigated the ultrasonographic characteristics of hypoechoic lesions using numerical analysis in image. In addition, we evaluated previously suggested subjective parameters on hypoechoic lesion. METHODS: We performed one-core targeted biopsy (TBx) for each hypoechoic lesion in up to two lesions in each patient before the 12-core systemic biopsy was obtained between July 2015 and May 2016...
March 5, 2018: World Journal of Urology
Le-Xing Zhang, Jing-Jing Xiang, Pei-Ying Wei, Jin-Wang Ding, Ding-Cun Luo, Zhi-Yi Peng, Zhi-Jiang Han
This study was to investigate the diagnostic value of the computed tomography (CT) histogram in thyroid benign solitary coarse calcification nodules (BSCNs). A total of 89 thyroid solitary coarse calcification nodules (coarse calcification ≥5 mm, no definite soft tissue around calcification) confirmed either by surgery or histopathological examination in 86 cases enrolled from January 2009 to December 2015 were evaluated. These included 56 BSCNs and 33 malignant solitary coarse calcification nodules (MSCNs)...
2018: Journal of Zhejiang University. Science. B
Myung Hee Chung, Bo Mi Gil, Soon Seog Kwon, Hae-Il Park, Sun Wha Song, Na Young Jung, Won Jong Yoo
OBJECTIVES: To determine what computed tomographic (CT) dimensions can predict obstructive lung disease on routine chest CT scans by comparing morphological and densitometric CT findings with pulmonary function test (PFT) in normal subjects and patients with chronic obstructive pulmonary disease (COPD). MATERIALS AND METHODS: Consecutive patients (n = 646; 260 females and 386 males; mean age 54.9 years, ranged 20-90 years) who received chest CT scans with densitometry during a 3-month period were retrospectively analyzed in single center...
March 2018: European Journal of Radiology
Daniel F Craft, Stephen F Kry, Peter Balter, Mohammad Salehpour, Wendy Woodward, Rebecca M Howell
PURPOSE: Using 3D printing to fabricate patient-specific devices such as tissue compensators, boluses, and phantoms is inexpensive and relatively simple. However, most 3D printing materials have not been well characterized, including their radiologic tissue-equivalence. The purposes of this study were to (1) determine the variance in Hounsfield Units (HU) for printed objects, (2) determine if HU varies over time, and (3) calculate the clinical dose uncertainty caused by these material variations...
March 1, 2018: Medical Physics
Ruben V C Buijs, Eva L Leemans, Marcel Greuter, Ignace F J Tielliu, Clark J Zeebregts, Tineke P Willems
OBJECTIVE: Quantification software for coronary calcification is often used to measure abdominal aortic calcification on computed tomography (CT) images. However, there is no evidence substantiating the reliability and accuracy of these tools in this setting. Differences in coronary and abdominal CT acquisition and presence of intravascular contrast may affect the results of these tools. Therefore, this study investigates the effects of CT acquisition parameters and iodine contrast on automated quantification of aortic calcium on CT...
2018: PloS One
Toru Higaki, Takeshi Nakaura, Masafumi Kidoh, Hideaki Yuki, Yasuyuki Yamashita, Yuko Nakamura, Fuminari Tatsugami, Yasutaka Baba, Makoto Iida, Kazuo Awai
Arterial peak enhancement on contrast-enhanced CT (CECT) images is thought to be higher in patients with low cardiac function. Using computer simulations, we tested the hypothesis that the relationship between the cardiac index and the aortic peak CT number (PCTN) is affected by the contrast material (CM) injection duration. We created computer simulation software for the contrast enhancement of various organs and vessels based on the Bae pharmacokinetics model and implemented models for CM transmission within organs and CM diffusion in blood plasma based on the osmotic pressure...
2018: PloS One
Anne T Davis, Antony L Palmer, Silvia Pani, Andrew Nisbet
PURPOSE: To define a method and investigate how the adjustment of scan parameters affected the image quality and Hounsfield units (HUs) on a CT scanner used for radiotherapy treatment planning. A lack of similar investigations in the literature may be a contributing factor in the apparent reluctance to optimise radiotherapy CT protocols. METHOD: A Catphan phantom was used to assess how image quality on a Toshiba Aquilion LB scanner changed with scan parameters. Acquisition and reconstruction field-of-view (FOV), collimation, image slice thickness, effective mAs per rotation and reconstruction algorithm were varied...
January 2018: Physica Medica: PM
Sara Khademi, Saeed Sarkar, Sharmin Kharrazi, Seyed Mohammad Amini, Ali Shakeri-Zadeh, Mohammad Reza Ay, Hossein Ghadiri
Increasing attention has been focused on the use of nanostructures as contrast enhancement agents in medical imaging, especially in computed tomography (CT). To date, gold nanoparticles (GNPs) have been demonstrated to have great potential as contrast agents for CT imaging. This study was designed to evaluate any effect on X-ray attenuation that might result from employing GNPs with a variety of shapes, sizes, surface chemistries, and concentrations. Gold nanorods (GNRs) and spherical GNPs were synthesized for this application...
January 2018: Physica Medica: PM
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