Impact of Sinogram Affirmed Iterative Reconstruction (SAFIRE) Algorithm on Image Quality with 70 kVp-Tube-Voltage Dual-Source CT Angiography in Children with Congenital Heart Disease

PURPOSE To compare the image quality and diagnostic accuracy between sinogram affirmed iterative reconstruction (SAFIRE) algorithm and filtered back projection (FBP) reconstruction algorithm at 70 kVp-tube-voltage DSCT angiography in children with congenital heart disease (CHD). MATERIALS AND METHODS Twenty-eight patients (mean age: 13 months; range: 2-48 months; male: 16; female: 12; mean weight: 8 kg) with CHD underwent 70 kVp DSCT angiography. Imaging data were reconstructed with both FBP and SAFIRE algorithms. Subjective image quality was evaluated on a five-point scale. The parameters of image noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) on the objective image quality were compared for the two reconstruction algorithms. Surgery was performed in 20 patients, whereas conventional cardiac angiography (CCA) was performed in 8 patients. The diagnostic accuracy was evaluated on the surgical and/or CCA findings. The effective radiation doses were calculated. RESULTS Compared to FBP algorithm, SAFIRE algorithm had significantly higher scores for subjective image quality (P<0.05), and lower image noise (P<0.05) as well as higher SNR & CNR values (P<0.05). There was no significant difference in the diagnostic accuracy between the FBP and SAFIRE algorithm (χ2 = 1.793, P>0.05). The mean effective dose for 70 kVp DSCT angiography was 0.30±0.13 mSv. CONCLUSIONS The SAFIRE algorithm can significantly reduce image noise and improve the image quality at 70 kVp DSCT angiography for the assessment of CHD in children.