This study aimed to compare the dose and noise level of four tube voltages in abdominal computerized tomography (CT) examinations in different abdominal circumference sizes of pregnant women. Fetal radiation doses were measured with two anthropomorphic pregnant phantoms and real‐time dosimeters of photoluminescence sensors using four tube voltages for abdominal CT. The noise level was measured at the abdomen of two anthropomorphic pregnant phantoms. In the large pregnant phantom, the mean fetal doses performed using 120 and 135 kV were statistically significantly lower than the lower tube voltages (P < 0.05). In the small pregnant phantom, the mean fetal dose performed by 100, 120, and 135 kV was significantly lower than the lowest tube voltage tested (P < 0.05). The ratios of the peripheral mean dose to the centric mean dose showed that the ratios of 80 kV were the highest and those for 135 kV were the lowest in both pregnant phantoms. The ratios of the peripheral mean dose to the centric mean dose decreased as the tube voltage increased. Compared with low tube voltages, high tube voltages such as 120 and 135 kV could reduce radiation doses to the fetus without compromising the image uniformity in abdominal CT examinations during pregnancy. On low tube voltage protocols, the dose near the maternal skin surface may be increased in large pregnant women because of reduced penetration of the x rays.

中文翻译：

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妊娠期腹部CT检查四管电压对胎儿的辐射剂量：一项幻影研究

本研究旨在比较不同腹围尺寸孕妇腹部计算机断层扫描（CT）检查中四种管电压的剂量和噪声水平。使用两个拟人化怀孕模型和光致发光传感器的实时剂量计，使用腹部 CT 的四个管电压来测量胎儿辐射剂量。噪音水平是在两个拟人化怀孕模型的腹部测量的。在大型怀孕体模中，使用 120 和 135 kV 执行的平均胎儿剂量在统计上显着低于较低管电压 ( P  < 0.05)。在小型怀孕体模中，100、120 和 135 kV 执行的平均胎儿剂量显着低于测试的最低管电压（P  < 0.05）。两组妊娠模型的外周平均剂量与中心平均剂量的比值显示，80 kV 的比值最高，135 kV 的比值最低。随着管电压的增加，外周平均剂量与中心平均剂量的比率降低。与低管电压相比，120、135 kV等高管电压在妊娠期腹部CT检查中可以在不影响图像均匀性的情况下减少对胎儿的辐射剂量。在低管电压方案中，由于 X 射线的穿透力降低，体型较大的孕妇靠近孕妇皮肤表面的剂量可能会增加。