Low concentration contrast medium and low radiation dose for infants and young children abdominal CT scanning / 中国介入影像与治疗学

ABSTRACT

Objective To assess the feasibility of low concentration contrast medium (270 mgI/ml) and low radiation dose (100 kV) for enhanced CT scanning in infants and young children abdominal CT examination.Methods Ninety children with abdomen tumors or abdominal injuries who underwent contrast-enhanced CT examination were selected.The patients were divided into 3 groups (each n＝ 30)Group A with tube voltage of 120 kV for non-contrast enhanced and parenchymal phase scanning and iodixanol contrast-medium (320 mgI/ml);group B with tube voltage of 100 kV for non-contrast enhanced and parenchyrnal phase scanning and iodixanol contrast-medium (270 mgI/rnl);group C with tube voltage of 100 kV for non-contrast enhanced and parenchymal phase scanning and iodixanol contrast-medium (270 mgI/ml).The 4-point scale was used to evaluate the quality of parenchymal phase imaging.The standard difference (SD) of CT value in subcutaneous fat,SNR and CNR of liver parenchyma,splenic parenchyma,renal cortical,renal vein,and abdominal aorta were measured at parenchymal phase,and CT dose index of volume (CTDI,ol),dose length product (DLP) and effective dose (ED) were recorded.The data were statistically analyzed among 3 groups.Results There was no significant difference of SNR,CNR nor objective scores of liver parenchyma,splenic parenchyma,renal cortical,renal vein and abdominal aorta among 3 groups (all P＞0.05).The differences of CTDIvol,DLP and ED among 3 groups were statistically significant (all P＜0.01).The CTDIvol had no statistical difference between group B and group C (P ＝ 0.001,0.002),DLP (P ＝ 0.013,0.004) and ED (P ＝ 0.03,＜0.001) of group A had statistical difference with those of group B and C.Conclusion CNR of the abdominal image can be guaranteed using low concentration contrast medium (270 mgI/ml) combined with 100 kV tube voltage for CT scanning of infants and young children,therefore satisfying clinical diagnostic requirements.