UNASSIGNED: Seventy-seven children (3-15 years) who had undergone a low dose CT with 140 or 100 kV were enrolled. The radiation dose was 1.40 mGy for the 3-8 years old and 2.61 mGy for 9-15 years old children. There were 116 pedicle screws evaluated. The raw data were reconstructed with adaptive statistical iterative reconstruction-V (ASIR-V) at 50% strength, ASIR-V with MAR (AV-MAR), deep learning image reconstruction (DLIR) at high strength and DLIR with MAR (DL-MAR). The image quality concerning pedicle screws was evaluated objectively in terms of the length of beam-hardening artifact (LHA) and artifact index (AI), and subjectively using a 4-point scale (4 points: best, 3 points: acceptable).
UNASSIGNED: Both AV-MAR and DL-MAR significantly reduced metal-induced beam hardening artifacts with smaller LHA (15.76±10.12 mm, a reduction of 57.24% and 15.66±10.49 mm, a reduction of 57.40%, respectively), and AI value (62.50±33.51, a reduction of 64.65% and 61.03±32.61, a reduction of 65.01%, respectively) compared to ASIR-V and DLIR (all P<0.01), The subjective image quality scores concerning the screws were 3.37±0.49 and 3.47±0.50 with AV-MAR and DL-MAR, respectively, higher than the respective value of 1.73±0.44 and 1.76±0.43 without MAR (all P<0.01).
UNASSIGNED: MAR significantly reduces the low-density artifacts caused by metal screws in post-surgery pediatric low-dose spine CT images, across different tube voltages, radiation dose levels and reconstruction algorithms. Combining DL-MAR further improves the overall image quality under low radiation dose conditions.
■纳入77名接受140或100kV低剂量CT检查的儿童(3-15岁)。3-8岁儿童的辐射剂量为1.40mGy,9-15岁儿童的辐射剂量为2.61mGy。评估了116枚椎弓根螺钉。原始数据用自适应统计迭代重建-V(ASIR-V)在50%强度下重建,ASIR-V与MAR(AV-MAR),高强度深度学习图像重建(DLIR)和带MAR的DLIR(DL-MAR)。根据射束硬化伪影(LHA)的长度和伪影指数(AI)客观地评估了椎弓根螺钉的图像质量。主观上使用4点量表(4点:最好,3分:可接受)。
■AV-MAR和DL-MAR均显着减少了具有较小LHA(15.76±10.12mm,减少57.24%和15.66±10.49毫米,减少了57.40%,分别),和AI值(62.50±33.51,减少64.65%和61.03±32.61,减少65.01%,分别)与ASIR-V和DLIR相比(均P<0.01),使用AV-MAR和DL-MAR,有关螺钉的主观图像质量评分分别为3.37±0.49和3.47±0.50,分别,高于无MAR的1.73±0.44和1.76±0.43(均P<0.01)。
■MAR显着减少了手术后儿科低剂量脊柱CT图像中金属螺钉引起的低密度伪影,跨不同的管电压,辐射剂量水平和重建算法。结合DL-MAR进一步提高了低辐射剂量条件下的整体图像质量。