[Investigation of Imaging Conditions Using Human Body Equivalent Phantom and Neonatal Phantom in Portable Chest Radiography of Newborns].

Purpose: Investigation of imaging conditions using human body equivalent phantom and neonatal phantom in portable chest radiography of newborns. Although attempts have been made to reduce dose by image processing in portable X-ray radiography of neonates, no evaluation has been made at the raw data level of the images. In this study, we investigated dose reduction from the current imaging conditions using a simulated phantom and a neonatal phantom in terms of raw data level image quality and incident surface dose.

Methods: The pixel values of each region were calculated from chest photographs of newborn infants taken at 60 kV and 2.0 mAs, and the thickness and combination of acrylic, aluminum, and copper were adjusted to create a simulated phantom with equivalent pixel values. The SdNR and incident surface dose at each site obtained from the simulated phantom were compared to obtain imaging conditions equivalent to or better than 60 kV, 2.0 mAs. The neonatal phantom was imaged, and the CNR of the processed images was compared to that of 60 kV, 2.0 mAs.

Results: SdNR and incident surface dose results showed that 62 kV, 1.8 mAs was superior. Comparison with neonatal phantoms showed no significant difference.

Conclusion: The simulated phantom was used to reproduce the clinical situation and to obtain excellent imaging conditions.