نتایج جستجو برای: scatter to primary ratio spr

تعداد نتایج: 10803318  

Journal: :iranian journal of medical physics 0
afshin akbarzadeh ph.d. student, department of medical physics and biomedical engineering and research center for science and technology in medicine, tehran university of medical sciences, tehran, iran mohammad rreza ay assistant professor in biomedical engineering, biomedical systems & medical physics dept., tehran university of medical sciences & research center for science and technology in medicine, tehran, iran. hossein ghadiri ph.d. student, department of medical physics and biomedical engineering and research center for science and technology in medicine, tehran university of medical sciences, tehran, iran saied sarkar associate professor in biomedical engineering, biomedical systems & medical physics dept., tehran university of medical sciences & research center for science and technology in medicine, tehran, iran.

introduction: one of the most important parameters in x-ray ct imaging is the noise induced by detected scattered radiation. the detected scattered radiation is completely dependent on the scanner geometry as well as size, shape and material of the scanned object. the magnitude and spatial distribution of the scattered radiation in x-ray ct should be quantified for development of robust scatter...

Afshin Akbarzadeh Hossein Ghadiri, Mohammad Rreza Ay, Saied Sarkar

Introduction: One of the most important parameters in x-ray CT imaging is the noise induced by detected scattered radiation. The detected scattered radiation is completely dependent on the scanner geometry as well as size, shape and material of the scanned object. The magnitude and spatial distribution of the scattered radiation in x-ray CT should be quantified for development of robust scatter...

Journal: :Medical physics 2001
J H Siewerdsen D A Jaffray

A system for cone-beam computed tomography (CBCT) based on a flat-panel imager (FPI) is used to examine the magnitude and effects of x-ray scatter in FPI-CBCT volume reconstructions. The system is being developed for application in image-guided therapies and has previously demonstrated spatial resolution and soft-tissue visibility comparable or superior to a conventional CT scanner under condit...

Journal: :Medical physics 2009
Ann-Katherine Carton Raymond Acciavatti Johnny Kuo Andrew D A Maidment

The purpose of this study is to evaluate the performance of an antiscatter grid and its potential benefit on image quality for a full-field digital mammography (FFDM) detector geometry at energies typical for temporal subtraction contrast-enhanced (CE) breast imaging. The signal intensities from primary, scatter, and glare were quantified in images acquired with an a-Si/CsI(T1) FFDM detector us...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه پیام نور - دانشگاه پیام نور استان تهران - دانشکده تربیت بدنی علوم ورزشی 1390

this research was conducted to examine the effect of a concurrent training on rest level of leptin of plasma and some hormonal factors in non-athlete subjects. the research population included non-athlete men who didn’t participate in any organized sport activities. 30 men were chosen voluntarily among the above-mentioned population and were divided into 2 groups: experimental (15 subjects) an...

2010
A Akbarzadeh MR Ay H Ghadiri S Sarkar H Zaidi

PURPOSE The consummate 64-slice CT scanner that spawns a new generation of non-invasive diagnostic tool, however revolutionary, brings with it the incidental by-product that is scattered radiation. The extended detector aperture capability in the 64-slcie CT scanner allows the effects of scattered radiation to be more pronounced and therefore demands that the magnitude and spatial distribution ...

Journal: :Medical physics 2004
J H Siewerdsen D J Moseley B Bakhtiar S Richard D A Jaffray

The influence of antiscatter x-ray grids on image quality in cone-beam computed tomography (CT) is evaluated through broad experimental investigation for various anatomical sites (head and body), scatter conditions (scatter-to-primary ratio (SPR) ranging from approximately 10% to 150%), patient dose, and spatial resolution in three-dimensional reconstructions. Studies involved linear grids in c...

Journal: :Japanese Journal of Radiological Technology 2000

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه تربیت مدرس - دانشکده برق و کامپیوتر 1390

one of the most important goals for increasing recognition and treatment revenue is transmitting vital data to medical care team, more quickly. nowadays, use of new technologies for transmitting data will deploy more and more daily. in this article, for transmitting electrocardiogram, first we code the signal into a suite of codes, then we will use bluetooth technology to transmit data from off...

2005
P. Ghaffarian A. A. Sharafi K. Keshavarz H. Zaidi

The MCNP Monte Carlo radiation transport code was used for calculation of scatter distribution and scatter-toprimary ratio (SPR) for different tube voltages, phantom thicknesses and field size in diagnostic radiology. Subsequently, the effect of grid’s design parameters such as strip density, grid ratio, interspace material and lead-tointerspace ratio on scatter rejection was investigated by ca...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید