Application of Sinogram-afifrmed Iterative Reconstruction in Routine Dose Temporal Bone High Resolution CT / 中国医学影像学杂志

ABSTRACT

PurposeTo evaluate the impact of filtered back-projection (FBP) and sinogram-affirmed iterative reconstruction (SAFIRE) technique on the image quality of routine dose temporal bone high resolution CT (HRCT) scan, and to provide reference for the realization of low dose scanning.Materials and Methods Sixty patients underwent routine dose temporal bone HRCT scan, 6 groups of images were reconstructed with FBP and SAFIRE (strength grade 1-5), average CT value, noise (SD), signal to noise ratio (SNR), contrast to noise ratio (CNR), subjective score and lesion detection were compared between different groups.Results There was no significant difference of average CT value among the 6 groups (P>0.05); compared with FBP, SD of SAFIRE (strength 1-5) reconstruction decreased gradually (F=1.78,P<0.01), which was 23.1%, 39.2%, 42.4%, 54.1% and 61.2% respectively; SNR and CNR increased gradually (F=1.42 and 3.15, P<0.05), SNR increased 26.6%, 40%, 71.1%, 117.7% and 153.3% respectively, while CNR increased 17.4%, 33.1%, 63.2%, 104.1% and 147.2% respectively. The differences among the 6 groups were statistically significant (P<0.05), subjective scores of SAFIRE 2-4 were higher than those of FBP, SAFIRE 1 and SAFIRE 5 group, while the difference among SAFIRE 2-4 group was statistically insignificant, reconstruction smoothness and edge sharpness of SAFIRE 3 group was better, with highest objective score.Conclusion Routine dose temporal bone HRCT scan combined with SAFIRE reconstruction can increase the image quality of temporal bone high resolution scan effectively, with the potential for radiation dose reduction.