title: Application of Low Tube Voltage 70 kV and Advanced Modeled Iterative Reconstruction in the Third-generation Dual-source CT to CT Colonography.
abstract: Objective To explore the feasibility of reducing radiation dose of CT colonography (CTC) while preserving image quality using the third-generation dual-source CT at 70 kV tube voltage with advanced modeled iterative reconstruction (ADMIRE). Methods This prospective study consecutively included 53 patients. All patients underwent CTC at 120 kV in supine position with filtered back projection reconstruction and at 70 kV in prone position with ADMIRE with the same scan range. Radiation dose and image quality were compared between these two protocols. Results CT dose index volume,dose-length product,and effective dose of 70 kV were (1.47±0.23)mGy,(68.85±13.82)mGy·cm,and (1.03±0.21)mSv,respectively,which were significantly lower than 120 kV mode [(2.96±0.61)mGy (t=25.356,P=0.000),(136.97±32.77)mGy·cm (t=22.246,P=0.000),and (2.05±0.49)mSv (t=22.293,P=0.000)]. Signal to noise ratio of 70 kV with ADMIRE was 3.60±0.58,which was obviously higher than that of 120 kV as 2.34±0.47 (t=-18.036,P=0.000). Noise of 70 kV with ADMIRE was (11.81±1.93)HU,which was obviously lower than that of 120 kV as (14.39±2.57)HU (t=7.856,P=0.000). The κ value of two radiologists' overall subjective image score was 0.843 (P=0.000). For 2D images,the noise score of 70 kV with ADMIRE was significantly lower (Z=325.000,P=0.000) and the overall image quality was significantly higher (Z=78.000,P=0.001) compared with 120 kV;however,the sharpness had no significant difference. All scores ranged from 4 to 5. For 3D virtual endoscopy,the overall image quality of 70 kV with ADMIRE and 120 kV was not significantly different (Z=4.000,P=0.059),and all scores ranged from 4 to 5. Conclusion CTC at 70 kV tube voltage combined with ADMIRE can remarkably reduce the radiation dose while maintaining imaging quality than 120 kV at third-generation dual-source CT.
authors.affiliation: Department of Radiology,PUMC Hospital,CAMS and PUMC,Beijing 100730,China.
authors.forename: Jingjuan
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Radiology,PUMC Hospital,CAMS and PUMC,Beijing 100730,China.
authors.forename: Weidong
authors.initials: W
authors.lastname: Pan
authors.affiliation: Department of Radiology,PUMC Hospital,CAMS and PUMC,Beijing 100730,China.
authors.forename: Huadan
authors.initials: H
authors.lastname: Xue
authors.affiliation: Department of Radiology,PUMC Hospital,CAMS and PUMC,Beijing 100730,China.
authors.forename: Bin
authors.initials: B
authors.lastname: Li
authors.affiliation: Department of Radiology,PUMC Hospital,CAMS and PUMC,Beijing 100730,China.
authors.forename: Xuan
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Radiology,PUMC Hospital,CAMS and PUMC,Beijing 100730,China.
authors.forename: Hao
authors.initials: H
authors.lastname: Sun
authors.affiliation: Department of Radiology,PUMC Hospital,CAMS and PUMC,Beijing 100730,China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Radiology,PUMC Hospital,CAMS and PUMC,Beijing 100730,China.
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.affiliation: Department of Radiology,PUMC Hospital,CAMS and PUMC,Beijing 100730,China.
authors.forename: Zhengyu
authors.initials: Z
authors.lastname: Jin
mesh_terms: D003106:Colon / Q000000981:diagnostic imaging*; D023881:Colonography, Computed Tomographic / Q000379:methods*; D006801:Humans; D016684:Prone Position; D011446:Prospective Studies; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted; D011877:Radionuclide Imaging; D059629:Signal-To-Noise Ratio