Comparison of full-field digital mammography system and dual-sided CR mammography system for imaging quality and radiation dose

Objective To compare imaging quality and radiation dose on full-field digital mammography (FFDM) system and dual-sided reading CR mammography (DSCRM) system.Methods The TRM of ALVIM statistics phantom was exposed by FFDM system and (DSCRM) with the same radiation dose.The exposure parameters and the entrance surface dose (ESD) were recorded.Then,the phantom was exposed by DSCRM system with different mAs and same kV,and the ESD was recorded.The images obtained above were read by three radiologists on the monitor of diagnosis work station with the same window width and window level.The evaluation of the images were given using a five-level confidence scale.ROC curves were drawn and probability Pdet were calculated.Results The ROC analysis of microcalcifications and masses showed A(z) values of 0.730-0.925 and 0.670-0.945 for FFDM,and 0.632-0.815 and 0.575-0.785 for DSCRM when the radiation dose is 1.36 mGy.The radiation dose with DR system could be reduced compared with dual-sided reading CR system at the same probabilities Pdet,the ESD reduced from 1.63 mGy to 1.36 mGy by 19.8％,the AGD reduced from 0.65 mGy to 0.56 mGy by 16.0％.Conclusions The observable details with FFDM system were proved to be superior to DSCRM system at the same radiation dose.With the similar image quality,the radiation dose of FFDM system was less than the DSCRM system. Key words: Full-field digital mammography; Dual-sided reading CR mammography system; Imaging quality; Radiation dose