In camera pre-calibration, images of a calibration object are commonly used to determine the internal geometry of a camera. The calibration imaging is often optimized to have the calibration object cover as large image area as possible. This is likely to yield a larger concentration of measured image points near the center of the image sensor. In this report, the hypothesis is investigated that...

BACKGROUND AND PURPOSE Improved image quality is clinically desired for contrast-enhanced CT of the neck. We compared 30% adaptive statistical iterative reconstruction and model-based iterative reconstruction algorithms for the assessment of image quality of contrast-enhanced CT of the neck. MATERIALS AND METHODS Neck contrast-enhanced CT data from 64 consecutive patients were reconstructed r...

Background: Cone-beam computed tomography (CBCT) scanners for image-guided radiotherapy are in clinical use today, but there has been no consensus on uniform acceptance to verify the CBCT image quality yet. The present work proposed new methods to fully evaluate the performance of CBCT in its three-dimensional (3D) reconstruction space. Materials and Methods: Compared to the traditional methods...

Background: To develop an optimal image reconstruction strategy for multidetector-row CT coronary angiography (MD-CTA) and to investigate its accuracy at different heart rates. Methodsl and Results: 70 patients consecutively underwent 16-row MD-CTA, 50 patients additionally had an invasive coronary angiography. Image reconstruction was performed both antegrade-proportional and antegrade-absolut...

introduction: in single photon emission computed tomography (spect), the projection data used for image reconstruction are distorted by several factors, including attenuation and scattering of gamma rays, collimator structure, data acquisition method, organ motion, and washout of radiopharmaceuticals. all these make reconstruction of a quantitative spect image very difficult. simulation of a sp...

This paper presents a 3-D reconstruction method IBM(image based modeling) of an image that does not contain any camera information. This system adopts a 3D reconstruction method based on a model. Model-based 3D reconstruction recovers an image using the geometric characteristics of a predefined polyhedron model. It uses a pre-defined polyhedron model as the primitive and the 3D reconstruction i...