不同靶/滤过组合对数字乳腺X线摄影辐射剂量和影像质量的影响  

Influence of different anode/filter combination on radiation dose and image quality in digital mammography

作　　者：柳杰[1] 刘佩芳[1] 张连连[1] 马文娟[1] 

机构地区：[1]天津医科大学肿瘤医院乳腺影像诊断科国家肿瘤临床医学研究中心乳腺癌防治教育部重点实验室天津市肿瘤防治重点实验室,300060

出　　处：《国际医学放射学杂志》2013年第5期414-417,共4页International Journal of Medical Radiology

基　　金：天津市抗癌重大科技专项(12ZCDZSY16000)

摘　　要：目的探讨数字乳腺X线摄影中应用不同靶／滤过组合对辐射剂量和影像质量的影响．便于实际工作中在保证影像质量的前提下，采用手动曝光模式合理选择靶／滤过组合，有效降低病人的辐射剂量。方法首先使用Serenity数字乳腺机（W／Ag）采用自动曝光模式对FlukeNA18-220模体中含有模拟钙化群、纤维及块状物的蜡块〈6mm）和不同厚度的BRl2模体（总厚度分别为1．6、2．6、3．6、4．6、5．6、6．6、7．6和8．6em）进行曝光，每一厚度模体分别曝光6次。然后使用Selenia数字乳腺机采用与自动曝光模式相同的管电压、管电流量、压力、压迫厚度及不同的靶／滤过组合（Mo／Mo、Mo／Rh）依次对每一厚度的模体进行6次手动曝光。最后记录两种曝光模式下每一厚度模体采用3种不同靶／滤过组合获得的平均腺体剂量（AGD）、对比噪声比（CNR）并计算品质因数（FOM）。应用SPSSl7．0统计学软件对不同厚度模体采用Mo／Mo、Mo／Rh和W／Ag3种不同靶／滤过组合产生的AGD、CNR和FOM进行单因素方差分析。结果随模体厚度的增加，Mo／Mo、Mo／Rh、W／Ag3种靶／滤过组合产生的AGD均升高，而CNR和FOM均降低。对于不同厚度的模体，3种靶／滤过组合产生的AGD、CNR和FOM问差异有统计学意义（均为P=0．000）。Mo／Mo组合的AGD值均为最高；模体厚度在1．6～2．6cm时．Mo／Rh组合的FOM最高：模体厚度在3．6～8．6t2Hl时，W／Ag组合的FOM值最高。结论模体厚度在1．6～2．6cm和3．6～8．6cm时．分别采用Mo／Rh、W／Ag组合所获得的FOM最高，可在保证影像质量的同时减少辐射剂量．总体成像性能要优于其他两种组合。Objective To explore the effect of different anode/filter combination on radiation dose and image quality in digital mammography, so as to choose optimal anode/filter combination to reduce radiation injury without sacrifying image quality. Methods Mammography aceredition phantoms with the thickness from 1.6 cm to 8.6 cm were used to simulate human breast tissue. The same exposure conditions, pressure, compression thickness, and different anode/filter combination were employed under the automatic and manual exposure modes. The image kV, mAs, pressure, filter, average glandular dose （AGD）, contrast to noise ratio （CNR） were recorded and the figure of merit （FOM） was calculated. SPSS 17.0 and one-way analysis of variance were used in the statistical analysis. Results As the phantom thickness increase, the AGD values which were acquired with Mo/Mo, Mo/Rh, and W/Ag three different anode/filter combinations were increased, but CNR and FOM values were decreased. AGD, CNR, and FOM values which were acquired in the phantom with different thickness, and three different anode/filter combinations were statistically different （P=O.000, respectively）. The AGD values of Mo/Mo were lowest. For 1.6 cm-2.6 em phantom thicknesses, the FOMs of Mo/Rh were lowest, and for 3.6 era-8.6 cm phantom thicknesses ,the FOMs of W/Ag were lowest. Conclusion Phantom thickness in 1.6 cm - 2.6 cm and 3.6 cm - 8.6 cm, Mo/Rh combination and W/Ag eombination respectively can achieve the highest FOM, and can provide the best imaging quality with low radiation （lose.

关 键 词：数字乳腺X线摄影 靶 滤过组合 平均腺体剂量 对比噪声比 品质因数 

分 类 号：R4[医药卫生—临床医学]