EVALUATION OF DIFFERENT COMPUTER CODES FOR GENERATION OF X-RAY SPECTRA IN GENERAL DIAGNOSTIC RADIOGRAPHY

Tóm tắt

This study presents the simulation results of the X-ray spectra of the general diagnostic radiography unit by using an empirical model (Spektr 3.0), semi-empirical models (IPEM 78 report No.78, SpekPy, and Xpecgen), and a Monte Carlo model (EGSnrc). The general diagnostic machine was assessed by quality assurance testing. The half-value layer (HVL), mean energy (Emean), and Air kerma per milliampere-second (Kair/mAs) have been measured at different tube voltages and compared with those obtained from five computer codes. The heel effect and target material composition were investigated. The IPEM report No.78 was used as a reference to compare with other computer codes. The comparative assessment showed that the HVL, Emean, and Kair/mAs were well-matched between the five codes and physical measurements in diagnostic radiology energy ranges. The Monte Carlo modeling is a sophisticated, precise computational tool that can characterize the spectra of newly developed target material compositions, complex geometrical configurations, and contributions of secondary particles, which are mostly empirical and semi-empirical models that currently can’t be performed accurately.