Application Of Low Radiation Dose And Low Iodine Contrast Agent Combined With Iterative Reconstruction Technique In CCTA TAG

ObjectiveTo evaluate the application value of iterative reconstruction technique combined with low radiation dose and low iodine concentration contrast agent in the transluminal attenuation gradient(TAG)of coronary artery CT.MethodsPatients undergoing CCTA between October 2017 and May 2018 were divided into two groups.Group A was examined using tube voltage of 120KV,370mgI/ml contrast agent,and traditional filtering reverse projection reconstruction methods.Group B used tube voltage of 100KV,300mgI/ml contrast agent and iterative reconstruction.Finally,75 examiners with CCTA and DSA were collected,including 41 cases in group A and 34 cases in group B.The effective radiation doses of the two groups were calculated,the image quality score was calculated,SNR and CNR were calculated,the narrow coronary artery branches confirmed in DSA were eliminated,the CT value in normal lumen was measured at the workstation,and the TAG was calculated.ResultsEDs of the two groups were 4.38+0.58 mSv and 3.20+0.69 mSv,while that of group B was significantly lower than that of group A,P<0.05.The two scorers had higher consistency of image quality score.There was no significant difference in image quality scores as well as SNR and CNR of LM,LAD,LCX and RCA of the two groups;P>0.05.A total of 139 tags,including LAD,LCX and RCA with no stenosis,were measured and compared between the two groups.There was no statistical difference between the two groups,P>0.05.ConclusionsCombined with the iterative reconstruction technology and used low radiation dose and low iodine contrast agent,the CNR and SNR of CCTA images will not decrease,that is,the image quality will not be affected,and there is no significant change in the coronary artery TAG measurement results.