Third version of vendor-specific model-based iterative reconstruction (Veo 3.0): Evaluation of CT image quality in the abdomen using new noise reduction presets and varied slice optimization

Objective: To qualitatively and quantitatively compare abdominal CT images reconstructed with a new version of model-based iterative reconstruction (Veo 3.0; GE Healthcare Waukesha, WI) utilizing varied presets of resolution preference, noise reduction and slice optimization. Methods: This retrospective study was approved by our Institutional Review Board and was Health Insurance Portability and Accountability Act compliant. The raw data from 30 consecutive patients who had undergone CT abdomen scanning were used to reconstruct four clinical presets of 3.75 mm axial images using Veo 3.0: 5% resolution preference (RP05n), 5% noise reduction (NR05) and 40% noise reduction (NR40) with new 3.75 mm "slice optimization," as well as one set using RP05 with conventional 0.625 mm "slice optimization" (RP05c). The images were reviewed by two independent readers in a blinded, randomized manner using a 5-point Likert scale as well as a 5-point comparative scale. Multiple two-dimensional circular regions of interest were defined for noise and contrast-to-noise ratio measurements. Line profiles were drawn across the 7 lp cm-1 bar pattern of the Catphan 600 phantom for evaluation of spatial resolution. Results: The NR05 image set was ranked as the best series in overall image quality (mean difference in rank 0.48, 95% CI [0.081-0.88], p = 0.01) and with specific reference to liver evaluation (mean difference 0.46, 95% CI [0.030-0.89], p = 0.03), when compared with the second best series in each category. RP05n was ranked as the best for bone evaluation. NR40 was ranked as significantly inferior across all assessed categories. Although the NR05 and RP05c image sets had nearly the same contrast-to-noise ratio and spatial resolution, NR05 was generally preferred. Image noise and spatial resolution increased along a spectrum with RP05n the highest and NR40 the lowest. Compared to RP05n, the average noise was 21.01% lower for NR05, 26.88% lower for RP05c and 50.86% lower for NR40. Conclusion: Veo 3.0 clinical presets allow for selection of image noise and spatial resolution balance; for contrast-enhanced CT evaluation of the abdomen, the 5% noise reduction preset with 3.75 mm slice optimization (NR05) was generally ranked superior qualitatively and, relative to other series, was in the middle of the spectrum with reference to image noise and spatial resolution. Advances in knowledge: To our knowledge, this is the first study of Veo 3.0 noise reduction presets and varied slice optimization. This study provides insight into the behaviour of slice optimization and documents the degree of noise reduction and spatial resolution changes that users can expect across various Veo 3.0 clinical presets. These results provide important parameters to guide preset selection for both clinical and research purposes.