低辐射剂量CT扫描技术在脑动脉3D打印中的应用研究

Application of low-dose CT scan in 3D printing of cerebral artery

摘要:

目的：探讨低辐射剂量CT扫描数据在脑动脉3D打印的可行性研究。方法：将临床拟行脑动脉3D打印的40例患者随机分为2组，每组20例。A组（常规剂量CT扫描方案）：120 kVp，350 mA和滤波反投影（FBP）算法；B组（低剂量CT扫描方案）：80 kVp，自动管电流调制技术（ATCM）和自适应统计迭代重建（ASiR）算法；2组对比剂浓度均为350 mgI/mL。采用两独立样本t检验（非正态分布采用Mann-Whitney U检验）来比较2组的临床资料、辐射剂量、CT DICOM数据客观评价指标及2组方案完成3D打印产物质量的主观评分。结果：A、B 2组患者的临床资料差异均无统计学意义（P＞0.05）。2组的CT辐射剂量差异具有显著统计学意义（P＜0.05），B组辐射剂量[（1.30 ± 0.47） mSv]较A组[（4.15 ± 0.62） mSv]减少约68.7%。2组脑动脉3D打印结果主观评分差异无统计学意义（P＞0.05）。2组CT DICOM数据客观评价指标：A组的背景噪声（BN）明显高于B组（P=0.000），而A组的信噪比（SNR）及对比噪声比（CNR）均低于B组（P=0.000）。结论：采用80 kVp、ATCM技术及ASIR算法的数据行脑动脉3D打印，在保证3D打印质量的同时，可以有效减低辐射剂量。

Abstract:

Objective：To investigate the feasibility of low-dose CT scan in 3D printing of the cerebral artery. Methods：A total of 40 patients who planned to undergo 3D printing of the cerebral artery were randomly divided into groups A and B，with 20 patients in each group. The patients in group A underwent CT at a conventional dose（120 kVp，350 mA） and filtered back projection，and those in group B underwent low-dose CT scan（80 kVp），automatic tube current modulation（ATCM），and adaptive statistical iterative re－construction（ASIR）；the concentration of contrast agent was 350 mgI/mL for both groups. The two-independent-samples t test was used for comparison of clinical data，radiation dose，objective evaluation indices of CT DICOM data，and subjective score of 3D printing quality between the two groups，and the Mann-Whitney U test was used for comparison of non-normally distributed data. Results：There were no significant differences in clinical data between groups A and B（P>0.05）. There was a significant difference in radiation dose between the two groups（P<0.05），and the radiation dose in group B was 68.7% lower than that in group A[（1.30±0.47） mSv vs. （4.15±0.62） mSv]. There was no significant difference in the subjective score of 3D printing quality between the two groups（P>0.05）. As for the objective evaluation indices of CT DICOM data，compared with group B，group A had significantly higher background noise and significantly lower signal-to-noise ratio and contrast-to-noise ratio（P<0.001）. Conclusion：3D printing of the cerebral artery us－ing 80 kVp，ATCM，and ASIR can effectively reduce radiation dose and guarantee the quality of 3D printing.