CAJ | 학술논문

目的研究数字X线摄影系统胸部管电压选择与影像质量的关系.方法固定摄影管电流为4 mAs;摄影管电压的选择从60 kV开始,然后逐级增加,每次增加10 kV,至摄影管电压达120 kV;用X线摄影系统对CDRAD2.0对比度细节体模和正常人体胸部进行曝光,测量体模表面x射线入射剂量.结果由5名3年以上工作经验的放射科医师对显示器的影像进行独立阅读,计算其图像质量因子(IQF)值和阅片得分.采用随机区组设计的方差分析(ANOVA),在不同管电压条件下,对5名观察者阅读后计算的IQF均数进行F检验,任意两曝光条件组之间的比较采用LSD-t检验(多重比较),以此结果确定最佳摄影管电压范围.正常人体胸部两种管电压条件下图像质量评分的比较采用配对t检验方法.结果 (1)体模表面X射线入射剂量随管电压的升高而增加,管电压从60 kV增加到120 kV,体模表面X射线入射剂量从63,4μGy增加到328.7 μGy.(2)随着摄影电压从60 kV增加至120 kV时,观察者在显示器观察到的CDRAD2.0体模IQF值分别为75.0±10.4、57.1±6.4、52.7±2.5,47.9±4.5,46.0±3.8、46.0±2.8、45.2±3.5,差异有统计学意义(F=19.10,P<0.01).(3)管电压90和120 kV两种摄影条件所得人体胸部图像的综合评分分别为(12.4±0.9)、(13.0±0.7)分,两者差异无统计学意义(t=1.500,P>0.05).结论 (1)随着X线摄影管电压的增大,显示器对图像细节的显示能力逐渐增强,摄影电压90 kV时,其显示分辨能力增加不明显.(2)在获得适当辐射剂量条件下,数字化X线胸部摄影适宜的摄影管电压为90 kV左右.
목적 연구수자X선섭영계통흉부관전압선택여영상질량적관계.방법 고정섭영관전류위4 mAs;섭영관전압적선택종60 kV개시,연후축급증가,매차증가10 kV,지섭영관전압체120 kV;용X선섭영계통대CDRAD2.0대비도세절체모화정상인체흉부진행폭광,측량체모표면x사선입사제량.결과 유5명3년이상공작경험적방사과의사대현시기적영상진행독립열독,계산기도상질량인자(IQF)치화열편득분.채용수궤구조설계적방차분석(ANOVA),재불동관전압조건하,대5명관찰자열독후계산적IQF균수진행F검험,임의량폭광조건조지간적비교채용LSD-t검험(다중비교),이차결과학정최가섭영관전압범위.정상인체흉부량충관전압조건하도상질량평분적비교채용배대t검험방법.결과 (1)체모표면X사선입사제량수관전압적승고이증가,관전압종60 kV증가도120 kV,체모표면X사선입사제량종63,4μGy증가도328.7 μGy.(2)수착섭영전압종60 kV증가지120 kV시,관찰자재현시기관찰도적CDRAD2.0체모IQF치분별위75.0±10.4、57.1±6.4、52.7±2.5,47.9±4.5,46.0±3.8、46.0±2.8、45.2±3.5,차이유통계학의의(F=19.10,P<0.01).(3)관전압90화120 kV량충섭영조건소득인체흉부도상적종합평분분별위(12.4±0.9)、(13.0±0.7)분,량자차이무통계학의의(t=1.500,P>0.05).결론 (1)수착X선섭영관전압적증대,현시기대도상세절적현시능력축점증강,섭영전압90 kV시,기현시분변능력증가불명현.(2)재획득괄당복사제량조건하,수자화X선흉부섭영괄의적섭영관전압위90 kV좌우.
Objective To study the relationship between the selection of tube tension in digitalchest radiograph and image quality.Methods When tube current was fixed at 4 mAs, the choice of X-ray tube voltage changed from 60 to 120 kV.CDRAD2.0 contrast details phantom and normal human chest were exposed by X-ray system with 7 kinds of tube voltage (the difference between tube voltage was 10 kV) ,and the X-ray incidental dose of phantom surface was measured.Five radiologists with 3 years working experience evaluated the image quality on monitor and calculated the image quality factor (IQF) and image reading score.Statistics analysis was then performed by using ANOVA test and t test.According to the results, the optimum tube voltage range was determined.Results (1) The incidental dose of phantom surface increased with the higher tube voltage.(2)When the tube voltage was changed from 60 kV to 120 kV, the IQF value observed in CDRAD2.0 phantom image on monitor was 75.0±10.4,57.1±6.4,52.7±2.5,47.9±4.5, 46.0±3.8,46.0±2.8,45.2±3.5 ,there was significant statistical differences between groups(F=19.10, P<0.01).(3)The integrated score of the chest image quality in the tube voltage 90 kV and 120 kV were 12.4±0.9 and 13.0±0.7, respectively, and there was no statistical difference between two groups(t= 1.500,P>0.05).Conclusions (1)With the increase of tube tension,the display capacity of display device gradually strengthened.When the tube tension exceeded 90 kV, the increase of image quality on monitor was not evident.(2) With proper radiation dose, the value of tube tension in digital X-ray chest photograph was about 90 kV.