Read by QxMD icon Read

Journal of X-ray Science and Technology

Patrick Trampert, Jonas Vogelgesang, Christian Schorr, Michael Maisl, Sviatoslav Bogachev, Nico Marniok, Alfred Louis, Tim Dahmen, Philipp Slusallek
BACKGROUND: Laminography is a tomographic technique that allows three-dimensional imaging of flat and elongated objects that stretch beyond the extent of a reconstruction volume. Laminography images can be reconstructed using iterative algorithms based on the Kaczmarz method. OBJECTIVE: This study aims to develop and demonstrate a new reconstruction algorithm that may provide superior image reconstruction quality for this challenged imaging application. METHODS: The images are initially represented using the coefficients over basis functions, which are typically piecewise constant functions (voxels)...
March 21, 2017: Journal of X-ray Science and Technology
Cruz Gloria, Sheng Dong Nie
In order to diagnose Parkinson disease (PD) at an early stage, it is important to develop a sensitive method for detecting structural changes in the substantia nigra (SN). Diffusion weighted imaging (DWI) and diffusion tensor imaging (DTI) have become important tools in supporting diagnosis of PD, with findings based on increased apparent diffusion coefficients (ADCs) in basal ganglia and decreased fractional anisotropy (FA) in SN. Based on the hypothesis that a diffusion kurtosis imaging (DKI) theory is a valuable method for PD diagnosis based on the non-Gaussian diffusion of water in biologic systems, the purpose of this study is to develop an image processing scheme (software) based on Image-J for the facilitating the application of DKI to assist PD diagnosis...
March 21, 2017: Journal of X-ray Science and Technology
Imad Ali, Nesreen Alsbou, Jean-Michel Taguenang, Salahuddin Ahmad
The objective of this study is to quantitatively evaluate variations of dose distributions deposited in mobile target by measurement and modeling. The effects of variation in dose distribution induced by motion on tumor dose coverage and sparing of normal tissues were investigated quantitatively. The dose distributions with motion artifacts were modeled considering different motion patterns that include (a) motion with constant speed and (b) sinusoidal motion. The model predictions of the dose distributions with motion artifacts were verified with measurement where the dose distributions from various plans that included three-dimensional conformal and intensity-modulated fields were measured with a multiple-diode-array detector (MapCheck2), which was mounted on a mobile platform that moves with adjustable motion parameters...
March 3, 2017: Journal of X-ray Science and Technology
Erdenetogtokh Jamsranjav, Kenichi Kuge, Atsushi Ito, Yasuhito Kinjo, Tatsuo Shiina
Soft X-ray microscopy has been developed for high resolution imaging of hydrated biological specimens due to the availability of water window region. In particular, a projection type microscopy has advantages in wide viewing area, easy zooming function and easy extensibility to computed tomography (CT). The blur of projection image due to the Fresnel diffraction of X-rays, which eventually reduces spatial resolution, could be corrected by an iteration procedure, i.e., repetition of Fresnel and inverse Fresnel transformations...
March 3, 2017: Journal of X-ray Science and Technology
J J Lifton
Since beam hardening causes cupping and streaking artifacts in computed tomographic images, the presence of such artifacts can impair both qualitative and quantitative analysis of the reconstructed data. When the scanned object is composed of a single material, it is possible to correct beam hardening artifacts using the linearization method. However, for multi-material objects, an iterative segmentation-based correction algorithm is needed, which is not only computationally expensive, but may also fail if the initial segmentation result is poor...
March 3, 2017: Journal of X-ray Science and Technology
Yi Yu, Jianlong Li, Lian Guo, Taifu Gu, Ruihai Xiao, Ye Ye, Qiufeng Pan, Yuanyuan Zhang, Hongwei Huang
Horseshoe kidney deformity with duplex urinary collecting systems is a rare congenital urinary tract defect. Clinically, it is very difficult to visually observe and examine the whole anatomic structure and information with the regular 2D diagnostic imaging tools. Here, we report a case in which a middle age patient has bilateral duplex urinary collecting systems and horseshoe kidney deformity accompanied with right renal ureteral calculi and hydronephrosis. It was diagnosed by magnetic resonance urography with urinary system 3D reconstruction...
February 21, 2017: Journal of X-ray Science and Technology
Haocheng Li, Wei Hong, Xuanqin Mou, Yu Liu
The objective of this study is to develop and test the feasibility of applying a machine learning method for geometry calibration of angles in micro-tomography systems. Increasing importance of micro-tomography systems are manifested with escalating applications in various scenarios including but not limited to oral and maxillofacial surgery, vascular and intervention radiology, among other specific applications for purposes of diagnosis and treatments planning. There is possibility, however, actual pathology is confused by artifact of tissue structures after volume reconstruction as a result of CT construction errors...
February 21, 2017: Journal of X-ray Science and Technology
Gennadiy Ayzenshtat, Dmitriy Prokopiev, Sergey Baidali, Oleg Tolbanov, Larisa Dorzheeva
PURPOSE: This study aims to analyse energy spectra formation in semiconductor X-ray pixel detectors using a simple experimental method. MATERIALS AND METHODS: The calculations were performed for the pixel detectors made of high-resistivity gallium arsenide compensated by chromium GaAs (Cr). A peculiar feature of these detectors is an extremely short lifetime of the holes. When using ordinary detectors with planar electrodes the spectra with high energy resolution could not be observed...
February 21, 2017: Journal of X-ray Science and Technology
Junchao Ma, Nan Yu, Cong Shen, Zhimin Wang, Taiping He, You-Min Guo
BACKGROUND: This study aims to develop a computerized scheme that utilizes a differential geometric approach to identify pulmonary vessels and then evaluate the performance of the scheme on the CT images of heavy smokers. METHODS: The scheme consists of two primary steps to segment entire lung vascular tree and identify the number of pulmonary vessels in a cross section. The scheme performance including accuracy, consistency, and efficiency was assessed using 102 chest CT scans...
February 3, 2017: Journal of X-ray Science and Technology
Hongli Shi, Zhi Yang, Shuqian Luo
BACKGROUND: The beam hardening artifact is one of most important modalities of metal artifact for polychromatic X-ray computed tomography (CT), which can impair the image quality seriously. OBJECTIVE: An iterative approach is proposed to reduce beam hardening artifact caused by metallic components in polychromatic X-ray CT. METHODS: According to Lambert-Beer law, the (detected) projections can be expressed as monotonic nonlinear functions of element geometry projections, which are the theoretical projections produced only by the pixel intensities (image grayscale) of certain element (component)...
February 3, 2017: Journal of X-ray Science and Technology
Weiwen Wu, Hengyong Yu, Shaoyu Wang, Fenglin Liu
The objective of this study is to present and test a new ultra-low-cost linear scan based tomography architecture. Similar to linear tomosynthesis, the source and detector are translated in opposite directions and the data acquisition system targets on a region-of-interest (ROI) to acquire data for image reconstruction. This kind of tomographic architecture was named parallel translational computed tomography (PTCT). In previous studies, filtered backprojection (FBP)-type algorithms were developed to reconstruct images from PTCT...
January 31, 2017: Journal of X-ray Science and Technology
I F Mikhailov, A A Baturin, A I Mikhailov, S S Borisova, M V Reshetnyak, D I Galata
A method for urinary iodine diagnostics using a portable energy-dispersion X-ray fluorescent (EDXRF) spectrometer is proposed. The principle of the method consists in excitation of the sample atoms fluorescence by the energy spectrum intentionally formed from the spectrum of an X-ray tube using an optimized X-ray scheme. The optimization by the criterion of the minimum detection limit for L-series iodine fluorescence lines included the calculation of optimal atomic numbers for materials of a re-radiator and a filter, and their thicknesses, the collimation system parameters, and an X-ray tube voltage...
January 31, 2017: Journal of X-ray Science and Technology
Nicolas Jaccard, Thomas W Rogers, Edward J Morton, Lewis D Griffin
BACKGROUND: Non-intrusive inspection systems based on X-ray radiography techniques are routinely used at transport hubs to ensure the conformity of cargo content with the supplied shipping manifest. As trade volumes increase and regulations become more stringent, manual inspection by trained operators is less and less viable due to low throughput. Machine vision techniques can assist operators in their task by automating parts of the inspection workflow. Since cars are routinely involved in trafficking, export fraud, and tax evasion schemes, they represent an attractive target for automated detection and flagging for subsequent inspection by operators...
January 31, 2017: Journal of X-ray Science and Technology
W G Kang, S H Pyo, T S Alkhuraiji, B S Han, C M Kang
The King AbdulAziz City for Science & Technology in the Kingdom of Saudi Arabia plans to build a 10 MeV, 15 kW linear accelerator (LINAC) for electron beam and X-ray. The accelerator will be supplied by EB Tech, Republic of Korea, and the design and construction of the accelerator building will be conducted in the cooperation with EB Tech. This report presents the shielding analysis of the accelerator building using the Monte Carlo N-Particle Transport Code (MCNP). In order to improve the accuracy in estimating deep radiation penetration and to reduce computation time, various variance reduction techniques, including the weight window (WW) method, the deterministic transport (DXTRAN) spheres were considered...
January 31, 2017: Journal of X-ray Science and Technology
Ailong Cai, Linyuan Wang, Lei Li, Bin Yan, Zhizhong Zheng, Hanming Zhang, Wenkun Zhang, Wanli Lu, Guoen Hu
Nowadays, diversities of task-specific applications for computed tomography (CT) have already proposed multiple challenges for algorithm design of image reconstructions. Consequently, efficient algorithm design tool is necessary to be established. A fast and efficient algorithm design framework for CT image reconstruction, which is based on alternating direction method (ADM) with ordered subsets (OS), is proposed, termed as OS-ADM. The general ideas of ADM and OS have been abstractly introduced and then they are combined for solving convex optimizations in CT image reconstruction...
January 31, 2017: Journal of X-ray Science and Technology
Chun-You Chen, Liang-Ming Lee, Hsiao-Wei Yu, Steve P Lee, Hsin-Lun Lee, Yung-Wei Lin, Yu-Ching Wen, Yi-Ju Chen, Chiu-Ping Chen, Jo-Ting Tsai
BACKGROUND AND PURPOSE: As recent studies have suggested relatively low α/β for prostate cancer, the interest in hypofractionated stereotactic body radiotherapy (SBRT) for prostate cancer is rising. The aim of this study is to compare dosimetric results of Cyberknife (CK) with Tomotherapy (HT) in SBRT for localized prostate cancer. Furthermore, the radiobiologic consequences of heterogeneous dose distribution are also analyzed. MATERIAL AND METHOD: A total of 12 cases of localized prostate cancer previously treated with SBRT were collected...
January 31, 2017: Journal of X-ray Science and Technology
Jainil P Shah, Steve D Mann, Martin P Tornai
OBJECTIVE: The purpose of this study was to utilize a dedicated breast CT system using a 2D beam stop array to physically evaluate the scatter to primary ratios (SPRs) of different geometric phantoms and prospectively acquired clinical patient data. METHODS: Including clinically unrealizable compositions of 100% glandular and 100% fat, projection images were acquired using three geometrically different phantoms filled with fluids simulating breast tissue. The beam stop array method was used for measuring scatter in projection space, and creating the scatter corrected primary images...
January 3, 2017: Journal of X-ray Science and Technology
Cheng Feng, Lixin Chen, Jian Li, Jiangtao Wang, Fajin Dong, Jinfeng Xu
OBJECTIVE: To compare a full-automated software to quantify 3D transthoracic echocardiography namely, 3DE-HM (three-dimensional echocardiography HeartModel, Philips Healthcare) with the traditional manual quantitative method (3DE-manual) for assessing volumes of left atrial and ventricular volumes, and left ventricular ejection fraction (LVEF). METHODS: 3D full volume images acquired from 156 subjects were collected and divided into 3 groups, which include 70 normal control cases (Group A), 17 patients with left ventricular remodeling after acute myocardial infarction (AMI) (Group B), and 69 patients with left atrial remodeling secondary to hypertension (Group C)...
2017: Journal of X-ray Science and Technology
Ka Hei Lok, Lin Shi, Xianlun Zhu, Defeng Wang
BACKGROUND: Brain tumor segmentation is a challenging task for its variation in intensity. The phenomenon is caused by the inhomogeneous content of tumor tissue and the choice of imaging modality. In 2010 Zhang developed the Selective Binary Gaussian Filtering Regularizing Level Set (SBGFRLS) model that combined the merits of edge-based and region-based segmentation. OBJECTIVE: To improve the SBGFRLS method by modifying the singed pressure force (SPF) term with multiple image information and demonstrate effectiveness of proposed method on clinical images...
2017: Journal of X-ray Science and Technology
Tingxi Wen, Zhongnan Zhang, Ming Qiu, Ming Zeng, Weizhen Luo
BACKGROUND: The computer mouse is an important human-computer interaction device. But patients with physical finger disability are unable to operate this device. Surface EMG (sEMG) can be monitored by electrodes on the skin surface and is a reflection of the neuromuscular activities. Therefore, we can control limbs auxiliary equipment by utilizing sEMG classification in order to help the physically disabled patients to operate the mouse. OBJECTIVE: To develop a new a method to extract sEMG generated by finger motion and apply novel features to classify sEMG...
2017: Journal of X-ray Science and Technology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"