Quasi-monochromatic cerium flash angiography

The cerium target plasma flash x-ray generator is useful in order to perform high-speed enhanced K-edge angiography using cone beams because K-series characteristic x rays from the cerium target are absorbed effectively by iodine-based contrast mediums. In the flash x-ray generator, a 150 nF condenser is charged up to 80 kV by a power supply, and flash x rays are produced by the discharging. The x-ray tube is a demountable diode, and the turbomolecular pump evacuates air from the tube with a pressure of approximately 1 mPa. Since the electric circuit of the high-voltage pulse generator employs a cable transmission line, the high-voltage pulse generator produces twice the potential of the condenser charging voltage. At a charging voltage of 80 kV, the estimated maximum tube voltage and current were approximately 160 kV and 40 kA, respectively. When the charging voltage was increased, the K-series characteristic x-ray intensities of cerium increased. The K lines were clean and intense, and hardly any bremsstrahlung rays were detected at all. The x-ray pulse widths were approximately 100 ns, and the time-integrated x-ray intensity had a value of approximately 10 μC/kg at 1.0 m from the x-ray source with a charging voltage of 80 kV. In the angiography, we employed a film-less computed radiography (CR) system and iodine-based microspheres.