Quantification of atherosclerotic plaques in carotid arteries by three-dimensional ultrasound

Abstract

The aim of this study was to develop three-dimensional (3D) ultrasound imaging of the carotid arteries in order to reduce intraexaminer and interexaminer variabilities of volume measurements in follow-up scans of atherosclerotic plaques. The non-invasive quantification of human atherosclerosis by 3D ultrasound was performed using a three-dimensional computer based image reconstruction. The linear movements of the transducer were driven by a motor triggered by electrocardiography. The method included an option to change angle of insonation and a correction of skin contact adaptation. Repeated measurements were performed at weekly intervals in 70 patients. Variabilities and ranges of three newly developed evaluation procedures of plaque volumes (manual tracing, threshold procedure, watershed algorithm) were used. Intraexaminer variability varied between 2.8% (watershed algorithm) and 4.1% (threshold procedure). Interexaminer variability ranged from 4.2% (manual tracing) to 7.6% (threshold procedure), follow-up measurements from 5.2% (watershed algorithm) to 9.4% (threshold procedure). Pearson correlation coefficients of interexaminer agreement and also those between all three measurement procedures were highly significant (p < 0.01). We conclude that the newly developed 3D computer based image reconstruction allows repeated quantification of moderate atherosclerosis with a high reliability.

Measurement of Carotid Plaque Volume by 3-Dimensional Ultrasound

“…14,15 Each observer sliced the 3D image with an ISD of 1.0 mm from 1 end of the plaque to the other (along the vessel axis in the scan direction) and traced the individual plaque boundaries on the image plane by using a mouse-driven cross-hair cursor. The areas measured in each slice were summed and multiplied by the ISD (ie, slice thickness) to calculate total plaque volume.…”

Recent developments in vascular ultrasound technology

“…These techniques usually have a long history in the research field before they were commercially adopted. Relevant dates are: 3D plaque volume (1994), 7 colour vector Doppler (1994), 15 wall motion (1968) 35 and shear wave imaging in arteries (2010). 68 In parallel to development time, the other issue is the clinical impact of these technologies.…”

Carotid Ultrasound Phenotypes Are Biologically Distinct

“…Early work in 3D ultrasound by Delcker and Diener, 28 Hennerici et al, 29 and Fenster's group [30][31][32] led to increasingly automated methods for measuring TPV [33][34][35] and vessel wall volume (VWV).…”