CAJ | 학술논문

目的比较CR与非晶体硅DR在胸部摄影中入射剂量的差异,探讨两者最优化曝光剂量.方法应用CR、DR分别别胸部模体行不同入射剂量曝光成像,记录模体表面入射剂量,用CDRAD2.0评估软件计算模体影像图像质量因子反数值IQFinv.CR组、DR组图像IQFinv差异用两独立样本t检验;CR组、DR组各自图像IQFinv与入射剂量的关系应用pearson相关;应用ROC曲线分析获取两组最佳图像IQFinv值,并换算曝光剂量.结果 CR和DR组入射剂量和图像质量IQFinv值之间呈明显的正相关(r=0.893、0.848,P<0.01),并存在线性回归.CR和DR组IQFinv值差异有统计学意义(t=5.455,P<0.05).ROC曲线分析(曲线下面积AUC=0.893,P<0.001),最佳IQFinv值为3.55.结论 CR、DR系统对于低对比度细节的检测能力均随着入射剂量的增加而增加.入射剂量相同时,DR系统对于低对比度细节的检测能力优于CR;在获得相同的图像质量时,与CR相比应用DR可大大降低被榆者辐射剂量.
목적 비교CR여비정체규DR재흉부섭영중입사제량적차이,탐토량자최우화폭광제량.방법 응용CR、DR분별별흉부모체행불동입사제량폭광성상,기록모체표면입사제량,용CDRAD2.0평고연건계산모체영상도상질량인자반수치IQFinv.CR조、DR조도상IQFinv차이용량독립양본t검험;CR조、DR조각자도상IQFinv여입사제량적관계응용pearson상관;응용ROC곡선분석획취량조최가도상IQFinv치,병환산폭광제량.결과 CR화DR조입사제량화도상질량IQFinv치지간정명현적정상관(r=0.893、0.848,P<0.01),병존재선성회귀.CR화DR조IQFinv치차이유통계학의의(t=5.455,P<0.05).ROC곡선분석(곡선하면적AUC=0.893,P<0.001),최가IQFinv치위3.55.결론 CR、DR계통대우저대비도세절적검측능력균수착입사제량적증가이증가.입사제량상동시,DR계통대우저대비도세절적검측능력우우CR;재획득상동적도상질량시,여CR상비응용DR가대대강저피유자복사제량.
Objective To compare the difference of entrance dose between CR and amorphous silocon DR system in chest imaging, and to discuss their optimum exposure dose. Methods For CR and DR, different entrance dose was measured by dosimeter in chest phantom. The value of IQFinv was analyzed by CDRAD2. 0 software. Image quality difference between CR and DR was assessed by group t-test. The relationship between image quality and entrance dose was tested by using Pearson correlation analysis. The best IQFinv values in CR and DR system were achieved via ROC curve analysis, and the exposure dose was then calculated. Results There were direct correlation values between entrance dose and the value of IQFinv in CR and DR system, respectively( r =0. 893 ,0. 848 ,P < 0. 01 ) . The linear regression equation for DR was IQFinv =0. 0050 +3. 359, and for CR was IQFinv =0. 005D + I. 651 , where D was entrance dose. The difference of IQFinv value between CR and DR was significant(t = 5. 455 ,P < 0. 05). The best IQFinv value of the two groups from ROC analysis was 3.55. Conclusions With the entrance dose increased, the detection ability of contrast-detail was elevated in the two digital radiography systems. With equal entrance dose, the detection ability of DR in contrast-detail was superior to CR. With equal image quality, DR obviously decreased the radiation dose to the patients.