background: patient radiation doses from computed tomography (ct) are increasing due to the number of ct examinations performed every day. the aim of this study was assess and evaluate patient radiation doses for adult’s common ct examinations to derive local diagnostic guidance levels for common ct examinations. materials and methods: volume and weighted computed tomography dose index (ctdivol...

Radiation technology such as X-ray computed tomography (X-ray CT) is a powerful tool for materials research. Such non-destructive imaging allows us to visualize in three dimensions (3D) the internal structure of without damaging specimen. This paper thus presents our studies on application microfocus CT, synchrotron radiation and integrated microtomography diffraction (CT-XRD) method advance ce...

Introduction: Computed tomography (CT) has numerous applications in clinical procedures but its main problem is its high radiation dose to the patients compared to other imaging modalities using x-ray. CT delivers approximately high doses to the nearby tissues due to the scattering effect, fan beam (beam divergence) and limited collimator efficiency. The radiation dose from multi-slice scanners...

Background and aims. Cone-beam computed tomography (CBCT) is an imaging system which has many advantages over computed tomography (CT). In CT scan, Hounsfield Unit (HU) is proportional to the degree of x-ray attenuation by the tissue. In CBCT, the degree of x-ray attenuation is shown by gray scale (voxel value). The aim of the present study was to investigate the relationship between gray scale...

Diversity in data is critical for the successful training of deep learning models. Leveraged by a recurrent generative adversarial network, we propose CT-SGAN model that generates large-scale 3D synthetic CT-scan volumes (\({\ge }224\times 224\times 224\)) when trained on small dataset chest CT-scans. offers an attractive solution to two major challenges facing machine medical imaging: number g...

With the advent of industrial computed tomography (CT or reconstruction from projections), which is of much wider scope than medical CT, the basic mathematical and physical assumptions need to be reconsidered. This paper considers the ramifications of the indeterminacy theorem and the underdetermined nature of the reconstruction equations. A search for truth rather than honesty in their solutio...

Introduction: The basis of image formation in Computed Tomography (CT) lies in the x-ray linear attenuation coefficient of the scanned material. Compton scattering and photoelectric effect are the dominant interactions of the x-ray photons with the subject, in the range of diagnostic radiology. These two coefficients are important in tissue characterization by Dual-Energy CT (D...