OBJECTIVE The aim of the study was to calculate the effective dose during fluoroscopy-guided pediatric interventional procedures of the liver in a phantom model before and after adjustment of preset parameters. METHODS Organ doses were measured in three anthropomorphic Rando-Alderson phantoms representing children at various age and body weight (newborn 3.5kg, toddler 10kg, child 19kg). Colli...

Modern computed tomography (CT) scanners use cone-beam configurations for increasing volume coverage, improving x-ray-tube utilization, and yielding isotropic spatial resolution. Recently, there have been significant developments in theory and algorithms for exact image reconstruction from cone-beam projections. In particular, algorithms have been proposed for image reconstruction on chords; an...

Following our previous report concerning the development of a 127 μm resolution, 7.4 million pixel, 30 x 40 cm active area, flat panel amorphous Silicon (a-Si) x-ray image sensor, this paper describes enhancements in image sensor performance in the areas of image lag, linearity, sensitivity, and electronic noise. New process improvements in fabricating a-Si thin film transistor (TFT)/photodiode...

An x-ray focusing crystal von Hamos spectrometer was developed using mica and graphite cylindrical crystals (radius of curvature R=20 mm) with a CCD linear array detector. The commercial CCD (Toshiba model TCD 1304AP) used for x-ray detection has 3724 pixels (8 μm width and 200 μm height) giving a total length of ~30 mm. The CCD detector was absolutely calibrated using laser-produced plasmas. T...

High resolution (AX/X z .015) x-ray spectra in the wavelength region 3.7 6.2 A (3.4 + 2.0 keV) have been collected from the Alcator tokamak using a flat crystal Bragg monochromator. Molybdenum L lines and chlorine K lines have been observed and charge state identifications have been made by comparison with calculations. I. Detection System A flat crystal monochromator with a pentaerythritol (PE...

An X-ray photoelectric polarimeter based on the Gas Pixel Detector has been proposed to be included in many upcoming space missions to fill the gap of about 30 years from the first (and to date only) positive measurement of polarized X-ray emission from an astrophysical source. The estimated sensitivity of the current prototype peaks at an energy of about 3 keV, but the lack of readily availabl...