The contrastive study of parameters of CT contrast agent in the kidney enhancement scanning

Objective:In order to use contrast agent reasonably and reduced incidence rate of contrast side-effect,the better contrast agent parameters in kidney CT contrast enhancement were established though compared the difference of agent concentration and flow rate.Methods:126 patients enrolled between January and June 2012 was accepted abdomen plain CT scan and contrast enhancement.Patients were excluded with allergy of contrast agent,severe hepatic cirrhosis,severe cardiac dysfunction,renal failure,severe hyperthyreosis,diabetes,abdominal occupying lesion and severe renal artery stenosis.126 patients were randomly allocated to receive different concentration and injection rate of CT agent(300 mgI/mL of agent concentration and 3 mL/s of injection rate;350 mgI/mL of agent concentration and 3 mL/s of flow rate;350mgI/mL of agent concentration and 5 mL/s of flow rate).All of the raw image data were exported to workstation(GE Adw 4.4) to analysis.CT values after injection of agents were measured in ROIs in abdominal aorta at the plane of left renal artery,left and right renal artery,left and right renal veins,left and right renal cortex and parenchyma at the transverse section,respectively.We observed the enhancement degree of that of tissue and evaluated the image quality in kidney with different kind of agent,different agent concentration and injection rate.Result:The enhancement values(x±s) of abdominal aorta,renal artery,renal vein,renal cortex,renal parenchyma from the group with the flow rate of 3 mL/s and the contrast concentration agent 300 mgI/mL were 287.74±49.83,276.24±44.57,141.61±20.87,136.67±24.50,168.31±25.45 respectively.The above index from the group with the flow rate of 3 mL/s and the contrast concentration agent 350 mgI/mL were 296.49±30.31,278.53±34.62,153.35±27.54,138.52±14.88,179.71±25.73 respectively.The test statistic analysis between two groups showed no significant difference(P0.05);The enhancement values(x±s)of abdominal aorta,renal artery,renal vein,renal cortical from the group with flow rate of 3 mL/s and the contrast concentration agent 350 mgI/mL were 296.49±30.31,278.53±34.62,153.35±27.54,138.52±14.88 respectively.The above index from the group with the flow rate of 5 mL/s and contrast concentration agent 350 mgI/mL were 411.83±54.13,405.69±54.03,207.98±37.21,199.32±55.33 respectively.The test statistic analysis between two groups showed significant difference(P0.001).Conclusion:In the kidney enhancement scanning,imaging data statistical analysis showed no significant difference between the two low flow rate groups of different concentration contrast agent.This study suggested to use lower concentration of contrast agent for patients to reduce the incidence rate of contrast side-effect reactions in simple abdominal organ enhancement scanning.In the renal vascular imaging scanning,imaging data statistical analysis showed significant difference between the two high concentrations groups of different injection velocity.This study suggested to select appropriate high velocity injection manner to improve vascular display resolution in abdominal vascular imaging scanning.