نتایج جستجو برای: phantom ct mtf phantom autocad modulation
تعداد نتایج: 300098 فیلتر نتایج به سال:
PURPOSE This study was performed to investigate the accuracies of the synthesized monochromatic images and effective atomic number maps obtained with the new GE Discovery CT750 HD CT scanner. METHODS A Gammex-RMI model 467 tissue characterization phantom and the CT number linearity section of a Phantom Laboratory Catphan 600 phantom were scanned using the dual energy (DE) feature on the GE CT...
The development and performance of a system for x-ray cone-beam computed tomography (CBCT) using an indirect-detection flat-panel imager (FPI) is presented. Developed as a bench-top prototype for initial investigation of FPI-based CBCT for bone and soft-tissue localization in radiotherapy, the system provides fully three-dimensional volumetric image data from projections acquired during a singl...
Fast variance prediction for iteratively reconstructed CT images is useful for the analysis of reconstruction algorithms and potentially for automatic tube current modulation. Prior methods are either computationally intractable or require impractical computation times to produce a map of the reconstructed image variance. In this paper we present the extension of prior work for fast variance pr...
Introduction: The performance of computed tomography is routinely checked using phantoms, which are known as important diagnostic imaging tools. Depending upon the aim of the study, different phantoms are designed, while trying to satisfy certain levels of diversities in their application. Material and Methods: The present study describes the...
In present PET/CT scanners, PET attenuation correction is performed by relying on the information given by CT scan. In the CT-based attenuation correction methods, dual-energy technique (DECT) is the most accurate approach, which has been limited due to the increasing patient dose. In this feasibility study, we have introduced a new method that can implement dual-en...
Comparison of radiation shields of different thicknesses and structures (especially different particle sizes of their constituents) is helpful to select an appropriate shield for patient protection in medical imaging tests particularly CT-scan. In this study micro- and nano-powders of bismuth were mixed with silicone matrix to make composite radiation shields for breast. The shields were provid...
how to cite this article: poor zamany nejat kermany m, modirian e, soroush m, masoumi m, hosseini m. phantom limb sensation (pls) and phantom limb pain (plp) among young landmine amputees. iran j child neurol. summer 2016; 10(3):42-47. abstract objective to determine the frequency of phantom limb sensation (pls) and phantom limb pain (plp) in children and young adults suffering landmine-relat...
OBJECTIVES (a) To assess the effects of computed tomography (CT) scanners, scanning conditions, airway size, and phantom composition on airway dimension measurement and (b) to investigate the limitations of accurate quantitative assessment of small airways using CT images. METHODS An airway phantom, which was constructed using various types of material and with various tube sizes, was scanned...
Purpose: To develop and test an integrated simulation system based on the digital Extended Cardio Torso (XCAT) phantom for 4-dimensional (4D) radiation therapy of lung cancer. Methods: A computer program was developed to facilitate the characterization and implementation of the XCAT phantom for 4D radiation therapy applications. To verify that patient-specific motion trajectories are reproducib...
OBJECTIVE The CT accreditation program was established in 2004 by the Korean Institute for Accreditation of Medical Image (KIAMI) to confirm that there was proper quality assurance of computed tomography (CT) images. We reviewed all the failed CT phantom image evaluations performed in 2005 and 2006. MATERIALS AND METHODS We analyzed 604 failed CT phantom image evaluations according to the typ...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید