Split-bolus Spectral Multidetector CT Of Portal Venous Imaging And Assessment Of Radiation Dose

Objective: Energy spectrum and id injection period enhanced CT scanof portal vein,to evaluate the display of the portal vein and the radiationdose.Materials and methods: Collected patients who take the examinationof the portal vein in our hospital from June2014to December2014,Selected the patients with normal portal vein and divided the patients intotwo groups at random,the experimental group:Portal vein single periodadult injection enhancement scanning and the control group:renal singleinjection of three phase enhancement scanning of portal vein.Experimental group have20cases,14cases were men,6cases werewomen,The average age was48.40±14.07years old; Control group21cases,12cases were men,9cases were women,The average age was55.62±10.12years old. Application of precious stones energy spectrum CT andAW4.6workstations for the image acquisition and analysis. Twoabdominal imaging diagnostic attending physician with Minimum5yearswork experience evaluate the CT enhanced images independently of thetwo groups. Evaluation points:1. Measurement of CT value of the Portalvenous trunk and the around liver parenchyma;2. Measurement of CT value of the Intrahepatic portal vein branch and the Psoas major;3.Measurement of CT value and SD value of the Abdominal subcutaneous fat;4. Measurement of DLP value of each scanning;5. Calculation of CNR andSNR value of the Intrahepatic and extrahepatic portal vein;6. Thesubjective evaluation: to score the display resolution of portal vein and itsmain branches.Using SPSS17.0software for statistical analysis of the data.Results:1. The Energy spectrum CT portal vein imaging got the bestsingle energy images at60kev.2.Quantitative evaluation of Portal veinenhancement degree by CT value:the CT value of the Intrahepatic andextrahepatic portal vein of the experimental group is higher compared withthe control group,there are statistically differences(p=0).3.The CNR valueof the portal vein imaging:the CNR of the Intrahepatic and extrahepaticportal vein and its branches of the experimental group is slightly highercompared with the control group,but have no statistically significantdifference.4.The SNR value of the portal vein imaging:the SNR of theIntrahepatic and extrahepatic portal vein and its branches of theexperimental group is higher compared with the control group.5.Quantitative analysis of Portal vein branches: the number of Portal veinbranches of the experimental group is slightly higher than the control groupwithout statistically significant difference(p=0.15);6.Portal vein subjectiveratings:The average score of the experimental group is14.25±1.02,thecontrol group is12.52±1.75,there are statistically significant differences(p=0);7:The analysis of the Radiation dose of the twogroups:the average effective radiation dose of the experimental group is8.08mSv,while the control group is17.36mSv,compared with the controlgroup,the experimental group Significantly reduced the radiation dose by53%of the patients in the checking process.Conclusion: Compared with the single injection Multiphaseimaging of Portal vein, on the premise of guarantee the quality of theportal vein image， the experimental group has greatly reduced theradiation dose by a drop of53%of the patients,it is an important andfeasible way of portal vein imaging.