Chulalongkorn Medical Journal


Background : Two digital mammographic systems of different targets and filters offerdifferent radiation doses to patients.Objective : To determine the average glandular dose (AGD), the entrance surface airkerma (ESAK) from cranio-caudal (CC) and medio-lateral oblique (MLO)projections and the dose reference level (DRL) from CC projection at bothbreasts when two digital mammogram systems of molybdenum (Mo) targetand molybdenum or rhodium (Rh) filters of one system and tungsten (W)target and rhodium filter of the other system were clinically used.Methods : Patients’ data from two digital mammography systems were analyzed interms of the compressed breast thickness (CBT), peak kilovoltage (kVp),milliampere-sec (mAs), average glandular dose (AGD, mGy), the entrancesurface air kerma (ESAK, mGy) and dose reference level (DRL, mGy) tooptimize the radiation dose to patient.Results : Six hundred female patients were studied from two digital mammographysystems from 2006 to 2009. Two hundred patient data for each target-filerof Mo-Mo, Mo-Rh and W-Rh were recorded for the CBT, kVp and mAs.The AGD was reduced by 41%, and the ESAK was reduced by 65% whenW-Rh target–filter was used. The dose reference level is determined forthe AGD and ESAK values.Conclusion : The radiation dose from digital mammogram system with the W-Rh targetfiltersystems was lower than the system with Mo-Mo and Mo-Rh targetfilter.The DRL from this study is less than IAEA recommendations in BasicSafety Standards.


Faculty of Medicine, Chulalongkorn University

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