The aim of this study was to compare a new device for the automatic evaluation of carotid diameter (D) and intima-media thickness (IMT) from ultrasound B-mode image sequences, with a RF echotracking system (RFES).

A total of 90 scans of the right/left common carotid artery from 21 patients with various cardiovascular risk factors and 12 healthy volunteers were analysed. The measurements were performed in real-time by using the two systems sequentially. Different Regions of Interest (ROI) were adopted, as our device best works on 1cm width ROI and the other on 4cm width ROI; a subgroup of scans (31) were analyzed using the same ROI width for the two systems. Moreover, on the healthy volunteers the analysis was repeated twice with each device in order to evaluate the intraobserver variability.

The agreement between the two systems was evaluated by Bland-Altman analysis; the bias and the standard deviation were 0.100mm and 0.190mm for D and 0.003mm and 0.057mm for IMT respectively. Moreover, in the subgroup where the same ROI width was adopted the bias and the standard deviation were: 0.060mm and 0.110mm for D and −0.006mm and 0.039mm for IMT. The coefficients of variation of the intraobserver measurements were: 2%±2% (D) and 5%±5% (IMT) for the RFES and 2%±1% (D) and 6%±6% (IMT) for our device.

In conclusion, although it is common opinion that B-mode based devices have lower precision than the RF based ones, our system shows reproducibility comparable to that of the RFES and good agreement with it.