Imaging characteristics of mobile digital radiographic system

Current digital radiography systems are rapidly growing in clinical applications. The purpose of this study was to evaluate the characteristics of a mobile digital radiographic system. The performance of the mobile DR system was evaluated by measuring the modulation transfer function (MTF), noise power spectrum (NPS), and detective quantum efficiency (DQE). Measurements were made on a LISTEM Mobix-1000 generator and a Teleoptic PRA Alpha- R4000 detector. Imaging characteristics were measured for these two systems using the IEC 61267's RQA5 (kVp: 74, additional filtration: 21 mmAl) radiographic condition. The result for the mobile DR system, MTF at 10% and DQE values using 0.19mR at 0 cycles/mm were measured as 2.4 cycles/mm and 43%, respectively. This high DQE at low frequencies may be useful for low frequency information. The NPS curves gradually decreased at high spatial frequencies. The NPS and the DQE curves show some exposure dependency with lower NPS and DQE value at higher exposure. The results suggested that mobile DR system could be integrated with emergency ambulance system in teleradiologic imaging applications.