Background: The current management of abdominal aortic aneurysm (AAA) hinges upon assessing diameter using ultrasound (US). Diameter reproducibility with conventional two-dimensional ultrasound (2D-US) is challenging and requires experienced operators. A novel automatic three-dimensional ultrasound (3D-US) system enables on-cart software-assisted diameter estimation (3D-SAUS), potentially facilitating more precise diameter measurements than 2D-US. This study aimed to assess the variance of AAA diameter measurements among US novices and experts by comparing 2D-US with 3D-SAUS in a clinical setting.
Methods: A total of 580 US scans were scheduled by 29 US operators (13 experts and 16 novices) on 10 patients with AAAs. Experts and novices measured all patients' AAA anterior-posterior (AP) diameters with 2D-US and 3D-SAUS. Outcomes were limits of agreement (LoA) using a mixed-effects model.
Results: In total, 564 of 580 planned US scans were performed. 500 US scans were automatically analyzed by the software and included. When using 3D-SAUS instead of 2D-US, novices reduced their LoA from ±16.5% to ±10.2% (P<0.001), reaching the experts' LoA of ±10.5% (P=0.782 for difference). The experts' LoA was ±10.5% for 2D-US and ±9.7% for 3D-SAUS, with no statistically significant difference between the two modalities (P=0.423).
Conclusions: Clinical implementation of the 3D-SAUS demonstrates a substantial reduction in variance in AAA diameter measurements among novice sonographers, surpassing the performance of conventional 2D-US techniques. Additionally, using the 3D-SAUS tool enables novice sonographers to achieve proficiency levels comparable to those of experts employing conventional 2D-US.