Experimental and clinical validation of arterial diameter waveform and intimal media thickness obtained from B-mode ultrasound image processing

A new automated computerized system (IoTEC(TM)) that assesses concomitantly the instantaneous temporal arterial diameter and intimal media thickness ( IMT) obtained from B-mode ultrasound (US) images was validated by sonomicro metry in sheep, by an echo-tracking system in humans, and by a Lucite phant om in vitro. Differences between methods for diameter measurements did not vary in any systematic way, with no significant differences in the lower fr equency range. Ultrasonic measurements of the true phantom gap sizes showed high correlation (r2 = 0.98,p < 0.001) with no systematic errors. Carotid and femoral arteries in humans were strongly related between IoTEC(TM) and echo-tracking device (r2 = 0.94 carotid; R2 = 0.88 femoral, p < 0.001), wit h a Gaussian distribution of the errors. This new method showed high intra- and interobserver repeatability of arterial diameter and IMT, allowing con sistent characterization of arterial dynamics in humans. (C) 1999 World Fed eration for Ultrasound in Medicine & Biology.