Image Quality of CT Angiography of Supra-Aortic Arteries : Comparison Between Advanced Modelled Iterative Reconstruction (ADMIRE), Sinogram Affirmed Iterative Reconstruction (SAFIRE) and Filtered Back Projection (FBP) in One Patients' Group.

PURPOSE: To evaluate the potential benefit in image quality of the iterative reconstruction (IR) technique advanced modelled iterative reconstruction (ADMIRE) in CT angiography (CTA) of supra-aortic arteries compared to sinogram affirmed iterative reconstruction (SAFIRE) and standard filtered back projection (FBP) in one patients' group.

METHODS: In this study 29 patients underwent standard CTA of supra-aortic arteries. Images were reconstructed using three different reconstruction algorithms, FBP, and IR techniques ADMIRE and SAFIRE. General image quality was assessed by two radiologists in different arterial segments using a 5-point Likert scale. Mean attenuation and noise were measured at different levels of each vessel and signal-to-noise ratio (SNR) was calculated. Interrater variability was determined.

RESULTS: Regarding total image quality IR showed only excellent, very good and good results and was more often graded excellent and very good than FBP reconstruction. Image noise levels and SNR were significantly (p < 0.01) improved in IR at the bilateral subclavian arteries (only in SAFIRE), vertebral V1 and V3 segments, common carotid arteries and proximal and distal internal carotid arteries. No significant differences in image quality were found when comparing SAFIRE and ADMIRE reconstructions except for V1 and V3. In these regions ADMIRE showed significantly better image quality than SAFIRE (p < 0.001 and p < 0.01). Interrater agreement was almost perfect (κ = 0.88) for different image quality parameters.

CONCLUSION: The CTA of supra-aortic arteries using the IR techniques SAFIRE and ADMIRE was superior to FBP when comparing the objective and subjective image quality and ADMIRE has the potential to overcome SAFIRE.