摘要
目的:探讨低参数设置和改良体位对学龄前儿童肘关节CT扫描图像质量及辐射剂量的影响。方法:前瞻性连续采集行肘关节CT检查的1~5岁患儿137例,采用随机数字表法将患儿分为A组48例、B组45例和C组44例。3组管电压均为80 kV,A组患儿患肢置于脊柱一侧,手臂尽量伸直,采用DoseRight技术;B组患儿患肢采用自制海绵垫抬高约45°,使患肢与脊柱和胸骨等不在同一平面内,采用DoseRight技术;C组患儿扫描体位同B组,采用固定管电流50 mAs。记录3组患儿的CT容积剂量指数(CT volume dose index,CTDIvol)和剂量长度乘积(dose length product,DLP),分别采用iDose^(4)和IMR算法进行图像重建,并对图像质量进行主观及客观评分。结果:组间比较显示,3组患儿iDose^(4)图像的主观和客观评分均为B组>A组>C组(P<0.05),IMR图像的客观评分亦为B组>A组>C组(P<0.05);组内比较显示,A组和C组IMR图像的主观和客观评分均高于iDose^(4)图像(P<0.05),B组患儿IMR和iDose^(4)图像主观及客观评分差异均无统计学意义(P>0.05)。3组患儿CTDIvol和DLP均为A组>B组>C组(P<0.05)。结论:患肢采用自制海绵垫抬高约45°,使患肢与脊柱和胸骨等不在同一平面内,在80 kV、50 mAs条件下进行儿童肘关节CT扫描是可行的,结合IMR重建算法能够进一步提高图像质量。
Objective:To explore the effects of low parameter setting and improved posture on the image quality and radiation dose of CT scanning of elbow joints in preschool children.Methods:The clinical data of elbow CT examination in 137 children aged 1-5 years were prospectively and continuously collected.The children were divided into the group A(n=48),group B(n=45)and group C(n=44)using the random number table method.The tube voltage in three groups was set as 80 kV.In group A,the affected limbs were placed on the side of the spine,the arms were straightened as far as possible,and the DoseRight technique was adopted.In group B,the affected limbs were raised about 45°by self-made sponge pad,the affected limbs were not in the same plane as the spine and sternum,and the DoseRight technique was adopted.In group C,the scanning position was the same as the B group,and the fixed tube current was 50 mAs.The CT volume dose index(CTDIvol)and dose length product(DLP)were recorded,the images were reconstructed using the iDose^(4)and IMR algorithms,and the image quality in three groups were subjectively and objectively scored.Results:The results of comparison between groups showed that the subjective and objective scores of iDose^(4)images in three groups were the group B>group A>group C(P<0.05),and the objective scores of IMR images were the group B>group A>group C(P<0.05).The results of intra-group comparison showed that the subjective and objective scores of IMR images in group A and group C were higher than those of iDose^(4)images,while the differences of the subjective and objective scores between IMR and iDose^(4)images in group B were not statistically significant(P>0.05).The CTDIvol and DLP in three groups were the group A>group B>group C(P<0.05).Conclusions:The CT scan of elbow in children is feasible under the affected limb is raised about 45°with self-made sponge pad,the affected limb is not in the same plane as the spine and sternum,the fixed tube current is 50 mAs,and the tube voltage is 80 kV.The IMR reconstruction algorithm can further improve the image quality.
作者
牟道远
边传振
王颖
张见
刘鹏
MOU Dao-yuan;BIAN Chuan-zhen;WANG Ying;ZHANG Jian;LIU Peng(Department of Radiology,Children′s Hospital Affiliated to Nanjing Medical University,Nanjing Jiangsu 210008,China)
出处
《蚌埠医学院学报》
CAS
2023年第5期625-628,632,共5页
Journal of Bengbu Medical College
