Quantitative Computed Tomography or “QCT” is a fast, non-invasive bone mineral density (BMD) exam of the lumbar spine or proximal femur, which utilizes low dose scan protocols on a standard Computed Tomography (CT) scanner. Originally developed in the early 80’s, QCT has several advantages over Dual-energy X-ray Absorptiometry (DXA) for the measurement of BMD in patients with degenerative disea...

Because the sizes of samples differ in x-ray micro-CT applications, it is desirable to have a mechanism to change the field of view of a micro-CT scanner. A well-known way to double the diameter of the field of view is to displace a detector array by 50%. In this paper, we propose to displace a detector array by an amount of greater than 0% but less than 50% for a continuously adjustable field ...

Multislice CT scanners are the newest class of CT scanners and they have not one but many detectors. These scanners can acquire up to 4 slices of data from the body in the same time it takes a single-slice CT scanner to acquire one. Multislice CT allows for rapid cardiac imaging during a single breath-hold. A multislice scanner operated in helical mode provides information that can be used to r...

Image reconstruction of a short portion of a long object using longitudinally truncated cone-beam data is important for major medical computed tomography (CT) applications, especially cardiac CT. Cardiac CT is an essential imaging tool for the diagnosis and therapeutic assessment of heart defects, cardiovascular diseases, and lung diseases, but it is still limited by suboptimal image quality. R...

Advanced applications of materials need sophisticated measurement methods for research, process development and quality control. X-ray Computed Tomography (CT) is a very powerful method for non-destructive testing of materials. A CT-scanner generates a series of X-ray attenuation measurements, which are used to produce computed reconstructed images of an object. In the last years 3D-CT systems ...

Introduction: The aim of the current study was to investigate the effects of X-ray radiation on some hematological parameters, morphology of red blood cells (RBC) and erythrocyte sedimentation rate (ESR) analysis of human blood using computed tomography (CT) scanner. Material and Methods: For the purpose of the study, 5 ml of wholeblood was drawn from vein puncture of 28 healthy people and div...

An experiment has been performed to demonstrate the feasibility of proton computed tomography. The proton energy loss was used to measure the projections of the relative stopping power of the phantom. High quality reconstructions were obtained from scans of 19cm and 30cm diameter performance phantoms. Comparison with reconstructions from an EM1 CT-5005 x-ray scanner showed the proton technique ...

Iodine is commonly used as a contrast agent in nonmedical science and engineering, for example, to visualize Darcy flow in porous geological media using X-ray computed tomography (CT). Undesirable beam hardening artifacts occur when a polychromatic X-ray source is used, which makes the quantitative analysis of CT images difficult. To optimize the chemistry of a contrast agent in terms of the be...

The introduction in 1998 of multi-detector row computed tomography (CT) by the major CT vendors was a milestone with regard to increased scan speed, improved z-axis spatial resolution, and better utilization of the available x-ray power. In this review, the general technical principles of multi-detector row CT are reviewed as they apply to the established four- and eight-section systems, the mo...