A feasibility study on reduction of the entrance-surface dose to neonates by use of a new digital mobile X-ray system.

We investigated the neonatal entrance-surface dose (ESD) and doses of scattered radiation emitted by a digital mobile X-ray system. The system is equipped with a novel flat-panel detector and is used in the neonatal intensive care unit. In the present study, the following three experiments were performed on frequently used X-ray-imaging condition: (1) the digital characteristics of the FPD were evaluated; (2) the ESD to a water-equivalent phantom was measured with a patient skin dosimeter (PSD); and (3) the scattered radiation around the incubator was measured with an ionization chamber survey meter. The digital characteristic curve showed that the system had excellent linearity and that the contrast characteristics were not affected by the tube voltage in the range of 50-110 kV. The ESD was 51-52 μGy with an 8-cm-thick phantom and 33-34 μGy with a 4.5-cm phantom, for one exposure. The doses measured around the incubator were 0.1-0.6 μSv or below measurable limits. Use of the new device demonstrates the potential of reducing the ESD to the patient and operator.