Radiation dose assessment in advanced synchrotron radiation facility is challenging due to the complexity and uncertainties of radiation source terms induced by high energy particle accelerator. Shanghai Synchrotron Radiation Facility (SSRF) is the first third-generation synchrotron facility in China, which was completed in 2009. Radiation dose assessment for workers at SSRF Beam lines is highl...

Purpose. – The aim of the present study was to quantitatively assess the performance of a block matching-based automatic registration algorithm integrated within the commercial treatment planning system designated ISOgrayTM from Dosisoft. The accuracy of the process was evaluated by a phantom study on computed tomography (CT), magnetic resonance (MR) and positron emission tomography (PET) image...

Brain function is widely investigated with functional magnetic resonance imaging (fMRI) in humans and animals. In fMRI, the time courses of voxels typically reflect the local blood-oxygen level, which is taken as an indicator of neuronal activity. Voxel timecourse correlations are often explicitly modeled and interpreted in terms of neuronal interactions. They also affect standard analyses that...

PURPOSE Many radiomics features were originally developed for non-medical imaging applications and therefore original assumptions may need to be reexamined. In this study, we investigated the impact of slice thickness and pixel spacing (or pixel size) on radiomics features extracted from Computed Tomography (CT) phantom images acquired with different scanners as well as different acquisition an...

In this paper, a new approach for haptic rendering of high resolution voxel-based anatomic models is presented. For visualization the surface location is determined by a ray-casting algorithm at sub-voxel resolution. Since the same algorithm is used for the haptics as well, a very high level of detail is achieved for haptic feedback. Both graphical and haptic representation is congruent. The in...

Minimally invasive interventions often involve tools of curvilinear shape like catheters and guide-wires. If the camera parameters of a fluoroscopic system or a stereoscopic endoscope are known, a 3-D reconstruction of corresponding points can be computed by triangulation. Manual identification of point correspondences is time consuming, but there exist methods that automatically select corresp...

Cone-beam CT (CBCT) has shown to be a useful imaging modality for various dentomaxillofacial applications. However, optimization and quality control of dental CBCT devices is hampered due to the lack of an appropriate tool for image quality assessment. To investigate the application of different image quality parameters for CBCT, a prototype polymethyl methacrylate (PMMA) cylindrical phantom wi...

annually, many people are irradiated for diagnostic and therapeutic purposes. assessment of radiation dose and its related risks to patients are important issues in radiation protection dosimetry. the complex mathematical calculations of the absorbed and effective doses are now done with computers. the calculations are performed with the help of anthropomorphic computational models of human bod...

Introduction: Monte Carlo (MC) is the most common method for simulating virtual SPECT projections. It is useful for optimizing procedures, evaluating correction algorithms and more recently image reconstruction as a forward projector in iterative algorithms; however, the main drawback of MC is its long run time. We introduced a model based method considering the effect of body attenuation and i...

In the event of a radiological accident caused by an external source, estimating the dose distribution in the victim's body is a relevant indicator in assessing biological damage from this exposure. This dose distribution can be assessed by physical dosimetric reconstruction methods. Physical dosimetric reconstruction can be achieved using experimental or numerical techniques. This article pres...