高千伏技术在CR检查中对被检者吸收剂量及图像质量的影响  

The effect of high kilovoltage technology on absorbed X-ray dose of subject and image quality in computed radiography

作　　者：李海波[1] 孙划[1] 杨湘山[2] 李四海[1] 

机构地区：[1]吉林省吉林市第二中心医院医学影像部,132001 [2]吉林大学公共卫生学院放射防护教研室

出　　处：《中国临床研究》2010年第11期965-967,共3页Chinese Journal of Clinical Research

基　　金：吉林科技发展计划资助项目(200903043)

摘　　要：目的探讨高千伏技术在计算机X线摄影(CR)中对被检者X线吸收剂量及图像质量的影响。方法将32例被检者以随机化原则分为对照组与研究组,每组各16例。对照组采用一般千伏技术(60～80kV)摄影,研究组采用高千伏技术(120kV)摄影。使用ToshibaDCW-20AX线机和KodakDirectViewCR975系统对被检者进行胸部摄影,用热释光剂量计测量被检者X线吸收剂量。由甲乙两名高年资放射科医师采用盲法对获得的CR图像质量以5分制作为等级评分标准进行评分,≥3分的图像被认为临床可接受,能够满足诊断要求。结果研究组X线吸收剂量为(0.22±0.03)mGy,对照组吸收剂量为(0.63±0.18)mGy(P<0.05);医师甲对研究组和对照组图像质量等级评分为3.88±0.50和4.19±0.54(P>0.05),医师乙对研究组和对照组图像质量等级评分为3.81±0.54和4.12±0.62(P>0.05)。结论与一般千伏技术比较,高千伏技术具有低辐射剂量及高分辨率的优点,因此在CR检查中使被检者X线吸收剂量明显降低,且图像质量能够满足诊断要求。Objective To explore the effect of high kilovohage technology on absorbed X-ray dose of examined sub- jects and image quality in computed radiography （CR）. Methods A total of 32 examined subjects were divided into research group and control group （n = 16 each）. High kilovohage （ 120 kV） radiography was adopted in research group, and general ki- lovohage （60 -80 kV） radiography was adopted in control group. The chest radiography was taken using Kodak DirectView CR 975 system, and absorbent X-ray dose of examined subject was detected by thermoluminescence dosimeter. The CR image qual- ity was evaluated blindly by two senior radiologists in a five grade marking system. The images whose grade being greater than 3 were considered clinically acceptable and qualified for diagnosis. Results The absorbed dose of X-ray in research group ob- viously decreased than that in control group[ （0. 22±0.03） vs （0. 63 ±0. 18） mGy,P 〈0.05]. The grade markings of image quality were similar （3.88 ±0. 50 vs 4. 19 ±0. 54 ,P 〉0. 05） in radiologists A,and also similar （3.81 ±0. 54 vs 4. 12 ±0. 62, P 〉 0.05 ） in radiologists B. Conclusions Compared with general kilovoltage radiography, high kilovohage radiography has advantages of low radiation dose and high image resolution, therefore absorbed X-ray dose of examined subjects obviously de- creases and the image quality can satisfy requirement of diagnosis.

关 键 词：高千伏 计算机X线摄影 X线吸收剂量 图像质量 

分 类 号：R814[医药卫生—影像医学与核医学]