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Purpose:To evaluate the feasibility of a low-dose 80kv scan protocol with iterative reconstruction algorithm(SAFIRE)in the CT enterography by comparing the image quality and radiation dose to conventional scan protocol.Method and materials:Sixty patients with intestinal diseases who underwent CT enterography on a DSCT(SOMATOM Definition Flash,Forchheim)from Aug.2013 to Mar.2014 were randomly divided into two groups(A,B).Before the 4 phase scan(unenhanced,arterial phase,portal vein phase,prone phase),a total of 2L liquid(20%Mannitol 500ml+5%Syrup1000ml+water 500ml)were taken as oral contrast agent for all patients.For group A,the routine scan protocol of our institute was used,in which the tube voltage was set as 100kV,reference mAs 280mAs with an aoutomatic tube current modulation method(CARE Dose4D).For group B,the first 3 phase scan protocol was set the same as group A.In prone phase,a low-dose scan protocol was used with tube voltage of 80kv and reference tube current of 280mAs(CARE Dose 4D).Images of group A were reconstructed with conventional FBP algorithm,while in group B an advanced iterative reconstruction algorithm(SAFIRE)was used.Image quality of the prone phase of both groups was analyzed subjectively and objectively.2 radiologists(5ys,2ys)scaled the images with 5 scores.The CT value,SNR were measured for each group of the liver,spleen substance and kidney,erector spinae and water of the Intestine regions of interest.Radiation dose values were recorded and SSDE(sized-specific dose estimates,AAPM 2014)was calculated.SPSS(ANOVA)was used to analysis statistical differences between two groups.Results: No significant differences(p>0.05)were found of SNR and Subjective scoring between two groups.Subjective scoring result of group A was 4.8±0.5 and in group B 4.6 ±0.6,which indicated in both groups good image quality was obtained.DLP significant differences(p<0.05)of group A was 267.16 ±50.74 mGy.cm,group B 177.33±35.88 mGy.cm.SSDE significant differences(p<0.05)of group A 10.49± 2.02,group B 5.96±0.6.Conclusion: The 80kV low-dose scan protocol combined with SAFIRE is feasible in the CT enterography,which allows for both comparable image quality to conventional scan and also significant low radiation dose.