髋关节数字化断层融合摄影的低剂量研究

目的 探讨髋关节数字化断层融合(DTS)摄影中最佳剂量比的设定,以最大程度地减少患者接受的辐射剂量.方法 90例行髋关节数字化断层融合摄影的患者,以随机数字表法,分别以6、7、8倍的剂量比组进行DTS检查,使用单因素方差分析比较不同剂量比设定下所得的图像质量和辐射剂量.结果 3组的表面吸收剂量(ESD)、剂量面积乘积(DAP)、图像质量评分分别为[(3.76±1.89)mGy、(18.41±11.71)dGy ·cm²、3.03±0.24]、[(5.24±2.76)mGy、(26.99±13.34)dGy ·cm²)、3.60±0.11]、[(6.39±1.75)mGy、(36.96±22.49)dGy ·cm²、3.64±0.09],各组间差异有统计学意义(F=10.94、9.45、139.26, P<0.05),通过3组间两两比较,ESD值和DAP值均是6倍剂量比组<7倍剂量比组<8倍剂量比组.6倍剂量比组的图像质量评分低于其他两组,7倍剂量比组和8倍剂量比组的图像质量评分差异无统计学意义.结论 剂量比是决定DTS检查辐射剂量的重要参数,髋关节DTS检查的剂量比设置为7时,可实现低曝光剂量和高图像质量的平衡,以最大限度地保护患者免受不必要的辐射损害.

Low-dose radiation in the hip digital tomosynthesis

Objective To explore the optimal dose ratio set in the hip digital tomosynthesis(DTS), and to reduce patient's examination dose as low as possible.Methods Ninety patients who received hip DTS examination were randomly divided into 3 groups, with the dose ratio as 6, 7 and 8, respectively. One-way ANOVA test was used to compare the image quality and radiation dose among 3 groups.Results The values of entrance surface dose (ESD), dose-area product (DAP) and image quality score of 3 groups were [(3.76±1.89)mGy, (18.41±11.71)dGy ·cm², 3.03±0.24], [(5.24±2.76)mGy, (26.99±13.34)dGy ·cm²), 3.60±0.11], and [(6.39±1.75)mGy, (36.96±22.49)dGy ·cm², 3.64±0.09], respectively. The difference among three groups was statistically significant (F=10.94,9.45,139.26, P<0.05).The S-N-K test showed that both ESD values and DAP values in 6,7,and 8 time-dose ratio group was from small to large. The image quality score of 6 time-dose ratio group was lower than that of the other groups with no significant difference.Conclusions Dose ratio is one of the important parameters to result in the radiation dose of DTS. Dose ration 7 is optimal in hip DTS, which could match the image quality and radiation dose best and finally protect patients from unnecessary radiation damage.