数字乳腺X线摄影不同靶/滤过组合对辐射剂量和图像质量的影响  

The influence of different anode-filter combinations on radiation dose and image quality of digital mammography

作　　者：赵红兰[1] 徐凯[1] 马红[1] 路欣[1] 李秋云[1] 吴笑松[1] 

机构地区：[1]徐州医学院附属医院医学影像科,江苏 徐州221002

出　　处：《实用放射学杂志》2015年第10期1704-1707,1711,共5页Journal of Practical Radiology

摘　　要：目的：探讨数字乳腺 X 线摄影不同阳极靶∕滤过组合对辐射剂量和图像质量的影响。方法首先采用自动曝光模式对44 mm、54 mm 和64 mm 的乳腺模体曝光,然后选择与自动曝光模式相近的管电压和管电流范围,采用钼∕钼（Mo/Mo）、钼∕铑（Mo/Rh）、铑∕铑（Rh/Rh）3种靶∕滤过组合对以上每种厚度的乳腺模体进行手动曝光,记录每次曝光的皮肤入射剂量（ESE）、平均腺体剂量（AGD）,计算二者的比值（ESE/AGD）,测量图像的信噪比（SNR）、对比噪声比（CNR）和品质因数（FOM）,对同一厚度3种靶∕滤过组合的辐射剂量和图像质量参数进行随机区组设计的方差分析。结果3种厚度不同靶/滤过组合的 AGD、ESE 和ESE/AGD 值的变化规律为 Mo/Mo〉Mo/Rh〉Rh/Rh,差别均有统计学意义（P 值均〈0.01）。3种厚度均显示 Mo/Mo 的 SNR 值最高、FOM 值最低,其中 Mo/Mo 和 Mo/Rh 之间的 SNR 差异无统计学意义（P 值均〉0.05）。44 mm 时,Rh/Rh 的 SNR 低于 Mo/Rh,Mo/Rh 的 CNR 和 FOM 均高于 Mo/Mo 和 Rh/Rh,差别均有统计学意义（P 值均〈0.01）。54 mm 和64 mm 时,Mo/Mo 的CNR 和 FOM 值显著低于 Mo/Rh 和 Rh/Rh（P 值均〈0.01）；Mo/Rh 和 Rh/Rh 之间的 CNR 和 FOM 值均无统计学差异（P 值均〉0.05）。结论不同靶∕滤过组合对辐射剂量有显著影响,对图像质量的影响与模体厚度有关,厚度越大 Mo/Mo 的图像质量越差, Rh/Rh 的成像性能越好。Objective To explore the effect of different anode-filter combinations on radiation dose and image quality of digital mammography.Methods Firstly,the phantoms with thickness of 44 mm,54 mm and 64 mm were exposed respectively under the automatic exposure control （AEC）mode,and then explored manually under the three different anode-filter combination modes inclu-ding molybdenum-molybdenum （Mo/Mo）,molybdenum-rhodium （Mo/Rh）and rhodium-rhodium （Rh/Rh）combination with the tube voltages and currents similar to the AEC mode,The entrance skin exposure （ESE）and average glandular dose （AGD）were re-corded for each exposure.The ESE-to-AGD ratio,signal-to-noise ratio （SNR）,contrast-to-noise ratio （CNR）and the figure of merit （FOM）were calculated to compare the radiation dose and image quality of the different anode-filter combinations.The randomized block design analysis of variance was used for statistical analysis.Results For the three phantom thickness,the AGD,ESE and ESE-to-AGD ratio in the three anode-filter combinations changed as Mo/Mo〉Mo/Rh〉Rh/Rh,and the differences were statistically sig-nificant （P 〈0.01）;the SNRs of Mo/Mo were the highest,but its FOMs were the lowest;the differences of SNR between Mo/Mo and Mo/Rh had no statistical significance （P ＆gt;0.05）.For the 44 mm phantom thickness,the SNR of Rh/Rh was the lowest,but CNR and FOM of Mo/Rh were the highest,and the differences were all statistically significant （P 〈0.01）.For the 54 mm and 64 mm phantom thickness,CNR and FOM of Mo/Mo were lower than those of the other two combinations,and the differences had statistical signifi-cance （P 〈0.01）;the differences between Mo/Rh and Rh/Rh had no statistical significance （P 〉0.05）.Conclusion Different anode-filter combinations have significant influences on radiation dose;the effects on image quality were related to the phantom thickness, the thicker the phantom,the worse the images of Mo/Mo,and the better the performance of Rh/Rh.

关 键 词：数字乳腺 X线摄影 靶/滤过组合 辐射剂量 

分 类 号：R814.41[医药卫生—影像医学与核医学] R323.23[医药卫生—放射医学]