CT球管参数设定对腰椎骨折3D打印模型影响的体模研究  

Effect of CT tube parameters setting on 3D printing model of lumbar vertebral fracture:a phantom study

作　　者：肖梦强[1] 张萌[1] 许英浩 刘金丰[1] 胡小露[1] 雷鸣[1] 赵奎[1] XIAO Meng-qiang;ZHANG Meng;XU Ying-hao(Department of Radiology,Zhuhai Hospital of Guangdong Hospital of Traditional Chinese Medicine,Guangdong 519015,China.)

机构地区：[1]广东省中医院珠海医院影像科,广东519015 [2]佳能公司,广州510000

出　　处：《放射学实践》2020年第9期1166-1171,共6页Radiologic Practice

摘　　要：目的:分析不同CT球管参数设定对腰椎骨折3D打印模型的影响,探讨适合腰椎骨折术前3D打印模型的低剂量CT扫描参数。方法:利用东芝640层CT对L1-L2椎体棘突骨折腰椎模型进行扫描,A、B两组的扫描管电压分别为120、100 kV,管电流均依次设定为160、140、120、100、80、60、40、20 mA。由两位高年资影像诊断主治医师对骨折线的可发现、可诊断和整体图像质量进行主观评价,另由两位高年资骨科主治医师对3D打印模型清晰度、手术指导情况进行主观评价,均采取3分评价法,评分≥2分为可接受。结果:两位医师对骨折线及3D打印模型的主观评价一致性均较好,各组3D打印模型评价均为3分。管电流为20 mA时,A、B两组L2棘突骨折线评分均为1分,图像质量差,其余骨折线评分均为2分或3分。不同参数L1-L5双侧椎弓根左右径宽度均值范围为9.42~10.19 mm,不同参数腰椎3D打印模型L2-L5双侧椎弓根上下径长度均值范围为12.15~12.52 mm,差异均无统计学意义(P值均>0.05)。A组管电流为20 mA,B组管电流为40 mA时,噪声最低,信噪比(SNR)、对比噪声比(CNR)最高,分别为11.7、15.31、95.72和8.62、30.97、165.10;随着辐射剂量降低,噪声降低,SNR、CNR升高。结论:采用低管电压、低管电流CT扫描能够满足3D打印模型的临床需求和腰椎骨折诊断需求。Objective:To analyze the effect of different CT tube parameters setting on 3D printing model of lumbar vertebral fracture,and to explore the low-dose CT scanning parameters suitable for 3D printing model of lumbar vertebral fracture before operation.Methods:The lumbar spinous process fracture model of L1-2 vertebral body was scanned with Toshiba 640-slice CT.The voltages of the scanner tube in group A and B were 120kV and 100kV,respectively.The currents of the scanner tube were set to 160mA,140mA,120mA,100mA,80mA,60mA,40mA and 20mA,respectively.Two senior radiologists have made subjective evaluation on the detection,diagnosis and overall image quality of the fracture line.And two senior orthopaedic doctors made subjective evaluation on the definition of 3D printing model and surgical guidance.Fracture line display and 3D printing model definition were evaluated by 3-point evaluation method,and the diagnosis was acceptable with the score more than 2 points.Results:The subjective evaluation of fracture line and 3D printing model by two physicians were in good agreement,and the evaluation of 3D printing model in each group was 3 points.The score of L2 spinous process fracture in both group A and B was 1 point in the setting of tube current 20mA,with poor image quality,while the score of other fracture lines was 2 or 3 points.The average width of left and right pedicle diameters between L1-L5 with different parameters ranged from 9.42mm to 10.19mm,and the average length of upper and lower pedicle meridians between L2-L5 in 3D printing model of lumbar spine with different parameters ranged from 12.15mm to 12.52mm,with no statistically significant difference(all P values>0.05).When the tube current in group A and B was set with 20mA and 40mA respectively,the noise was the lowest and the signal-to-noise ratio(SNR)and contrast noise ratio(CNR)were the highest(11.7,15.31 and 95.72 in group A,respectively;8.62,30.97 and 165.10 in group B,respectively).With the decrease of radiation dose and noise,SNR and CNR increase.Concl

关 键 词：腰椎骨折 体层摄影术 X线计算机 3D打印 低管电压 低管电流 辐射剂量 

分 类 号：R683.2[医药卫生—骨科学] R814.42[医药卫生—外科学]