The goal in medical x-ray imaging is to obtain the image quality required for a given detection task, while ensuring that the patient dose is kept as low as reasonably achievable. The two most common strategies for dose reduction are: optimizing incident x-ray beams and utilizing energy information of transmitted beams with new detector techniques (spectral imaging). In this thesis, dose optimi...

Non-destructive measurements of contaminated soil core samples are desirable prior to destructive measurements because they allow obtaining gross information from the core samples without touching harmful chemical species. Medical X-ray computed tomography (CT) and time-domain low-field nuclear magnetic resonance (NMR) relaxometry were applied to non-destructive measurements of sandy soil core ...

introduction: in 2000, the unscear reported that ct constitutes 5% of all the medical x-ray  examinations and it contributes 34% of the resultant collective dose worldwide. children are more  sensitive to the ionizing radiations than adults. so, routine quality control tests are expected to be  carried out periodically on the ct scanners. the aim of this research was to estimate the effective  ...

Three-dimensional high-resolution images of density distributions were obtained on unsplit cores using a medical X-ray computed tomography (CT) scanner. The resolution of CT scanning is about 0.6 mm2 and allows a 5-mm depth for beam width. Electrical resistivity measurements were also conducted to know porosity at high depth resolution after core splitting. Wholeround core samples for this stud...

Using advanced X-ray technologies and X-ray scattering enhancement in signal detection, a compact laboratory X-ray scanner for 3D non-invasive imaging with 150-200 nanometers 3D detail detectability has been created. This spatial resolution in the volume terms is equal or better than can be achieved in synchrotron tomography, 5 orders better than in existing laboratory instruments and 10-12 ord...

The motivation behind this thesis is illustrated by the fact that many breast cancers are missed at X-ray mammography, insufficient contrast being the most important reason. The present thesis considers the diffraction-enhanced imaging (DEI) technique for imaging in vitro breast tumours. DEI is one of the novel methods in which the change in X-ray wavefront phase or propagation direction at the...

Forintek Canada Corp. and the University of Northern B.C. have recently opened the new CT Imaging Centre in Vancouver, Canada. The facility is designed specifically for forest products research and can provide high-resolution CT and radiographic images of logs and other large objects. The system has a 3.5 MeV x-ray source, a scan envelop 1m in diameter by 5m in length, and special equipment for...

OBJECTIVE Computed tomography (CT), rather than conventional 2-dimensional radiography, was used to scan and measure pelvic parameters. The results were compared with measurements using X-ray. METHODS Pelvic parameters were measured using both CT and X-ray in 254 patients who underwent both abdomino-pelvic CT and X-ray at the pelvic site. We assessed the similarity of the pelvic parameters be...

The current work describes an anthropomorphic beating heart phantom constructed as a tool for the assessment of technological advances in cardiac x-ray computed tomography (CT). The phantom is comprised of a thorax, a compressor system, an ECG system, a beating heart with tortuous coronary arteries, and the option to add or remove pathologies such as aberrant beats, stents, and plaques. Initial...

Radiologic Procedure Rating Comments RRL* CT abdomen and pelvis without and with IV contrast 2 ☢ ☢ ☢ ☢ X-ray abdomen 2 ☢ ☢ CT abdomen and pelvis without IV contrast 2 ☢ ☢ ☢ ☢ CT abdomen and pelvis with IV contrast 2 ☢ ☢ ☢ ☢ X-ray IV contrast enema 2 ☢ ☢ ☢ X-ray cystography 2 ☢ ☢ ☢ MRI pelvis without and with IV contrast 2 MRI may be indicated if urethral diverticulum is suspected. O MRI pelvis ...