To study the effects of different detector widths and scanning modes on image quality and radiation dose of head Computed Tomography Angiography (CTA) in wide-detector CT.

(1) Phantom study: A PBU-60 angiography phantom of head was examined on Revolution CT. Group A、B and C were respectively examination with 160 mm axial scanning mode, 40 mm axial scanning mode and 40 mm spiral scanning mode. The objective evaluation of image [Standard Deviation (SD), Signal to Noise Ratio (SNR) and Contrast to Noise Ratio (CNR)] were estimated. Then the radiation dose, dose efficiency and scanning time were recorded. (2)Clinical study: to prospectively select 60 patients for head CTA, randomly divided into group 1...

(1) Phantom study: There were no significant differences in the image noise, SNR and CNR between groups A, B and C (P>0.05)；The CTDI of group A、B and C were 9.17, 8.55 and 9.32 mGy respectively；The DLP of group A, B and C were 146.8, 136.76 and 176.38 mGy·cm respectively; The dose efficiency of group A and C was 89% , and the dose efficiency of group B was 96.78%; The examination time of group A, B and C were 6.5, 0.5 and 2.41s respectively. (2)...

Revolution wide-detector CT with 160 mm axial scanning mode only single scan can cover the entire cerebral vascular, which can reduce the radiation dose, improve the dose efficiency, and reduce the examination time while ensure the image quality.

T. Song; Chengdu/CN - nothing to disclose Z. Li; Chengdu, SICHUAN/CN - nothing to disclose

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