【摘 要】
:
Focal spot size is an important factor that affects the spatial resolution and the projection image unsharpness.More seriously,the size and position of the focal spot may change as time goes or when t
【机 构】
:
Paul Lauterbur Center for Biomedical Imaging Research,Institute of Biomedical and Health Engineering
【出 处】
:
长江2011国际医学影像物理和工程应用大会暨第六届中国医学影像物理学术年会
论文部分内容阅读
Focal spot size is an important factor that affects the spatial resolution and the projection image unsharpness.More seriously,the size and position of the focal spot may change as time goes or when the tube voltage or power set change especially in micro cone-beam CT.It is necessary to monitor the focal spot state in real time when doing CT scanning.In this paper,a tungsten wire with the diameter of 100 microns is used to test the state changing.The wire is placed between the tube and the fiat panel detector.After the tube is opening,the projection of the wire is acquiring in time.Based on the wire projection edge or midline position movement,we can acquire the information of the focal spot poison changing direction.In addition,based on the wire width change,the information of the focal spot size can be obtained.A serious of different voltages and powers are set in the experiment.When the tube power changes from 3 watt to 15watt at fixed tube voltage,the wire projection position and width change a little.When the tube voltage changes from 100kV to 200kV at fixed power,both of the wire projection edge and the width have varied.The real-time observation of the wire projection status can be used for the analysis of the spatial resolution of the micro cone-beam CT system.
其他文献
The tumor volume delineation is a key step for the improvement of precision of tumor radiotherapy.The multimodality image fusion between CT and MRI,or PET and CT,or PET and MRI can obviously compensat
Biomedical signals and images are usually characterized as highly noisy and nonstationary.To extract transient and tiny features from noisy and complicated biomedical signals or images often requires
Magnetoacoustic imaging with electrical exciting is a newly proposed imaging approach to conduct noninvasive electrical conductivity imaging of biological tissue.The imaging method is studied via comp
Introduction Segmentation of masses plays a very important role in mammogram computer-aided diagnosis (CAD) system.Most of the traditional mass segmentation methods focused on the establishment of app
MRI (magnetic resonance imaging) has been widely used in clinical diagnosis and basic medical researches.The analysis methods of medical image have been developed from visual qualitative analysis to q
Purpose Malignant gliomas are almost uniformly fatal and display exquisite radiation resistance.Mutations in P53 tumor suppressor gene occur correlation with improved survival and enhanced respond to
Objective: Establish a three-dimensional (3D) visualization system of medical images.Threedimensional visualization plays an essential and crucial role in disease diagnosis and treatment planning of p
To better explore the abundant information of brain regions involved in functional magnetic resonance imaging (fMRI) data during task status,especially the pattern of information transfer concerned in
Introduction Imaging is an essential tool to facilitate clinical diagnosis in ophthalmology.Currently most of the medical images are analyzed by human graders,which is very subjective.In this paper,co
In this study,we developed a method of estimating the cerebral metabolic rate of glucose (CMRglc) using one sample of the input function in cerebral 18F-Fluoro-deoxigen-glucose (18F-FDG) positron emis