Differences in effective dose and energy imparted estimation from PA–AP, RLAT–LLAT projections in pediatric full spine x-ray examination using the Monte Carlo technique

Abstract
Effective dose (E) and energy imparted (epsilon) can be used to quantify the risk of radiation-induced carcinogenesis or hereditary effects arising from radiographic exposures. When the children are examined or treated for idiopathic scoliokyphosis it is important to estimate E and epsilon in the patients due to full spine x-ray examination. The aim of this study is to calculate E and epsilon in the case of children of 5 and 10 years old who undergo full spine x-ray examination using the Monte Carlo approach. Dose area product (DAP) and entrance surface dose (ESD) were also used. AP, PA, RLAT, LLAT projections are simulated by using appropriate energy spectra. According to the results, the effective dose (E) and the energy imparted (epsilon) are smaller at PA projection than AP, although for spine the opposite occurs, in agreement with previous studies. On the other hand, E and epsilon do not differ statistically among RLAT and LLAT projections. Moreover, the role of lung and bone as tissue inhomogeneities in epsilon is shown to be very important.