Spyretta Golemati, Presenter: Nothing to Disclose

Symeon Lehareas, Abstract Co-Author: Nothing to Disclose

Nikolaos Tsiaparas, Abstract Co-Author: Nothing to Disclose

Achilleas Chatziioannou, Abstract Co-Author: Nothing to Disclose

Despina Perrea, Abstract Co-Author: Nothing to Disclose

Konstantina Nikita PhD, Abstract Co-Author: Nothing to Disclose

Ultrasound-image-based texture is promising toward improved assessment of cardiovascular risk.

Valid identification of the vulnerable asymptomatic carotid atherosclerosis remains a crucial clinical issue. Multiresolution texture analysis has been shown to characterise atheromatous tissue, especially in terms of horizontally oriented texture in longitudinal B-mode sections. We investigated these texture properties at three distinct areas of the diseased arterial wall (the plaque, the wall adjacent to it and the plaque shoulder, i.e. the boundary between plaque and wall), in an attempt to describe tissue discontinuities along the asymptomatic arterial wall.  

We interrogated 25 arteries, 11 with low (50-69%) and 14 with high (70-100%) stenosis degrees. The two groups had similar ages. Multiresolution analysis was performed using wavelet packets and the coiflet1 wavelet, for three levels of decomposition. At the first decomposition level, four subimages were derived, including one approximation and three detail subimages (horizontal, vertical and diagonal). At each subsequent level, four subimages were derived from each subimage of the previous level. Seven horizontal detail subimages were retained and their mean and standard deviations were the derived texture features, yielding a total of fourteen features, each estimated at systole and diastole. Between high and low stenosis cases, 9 features were statistically different (Wilcoxon rank sum test, p-value<0.05) in the plaque shoulder at systole and 4 at diastole. No differences were observed for the site of the plaque nor for the wall adjacent to it. Texture differences along the wall (wall – shoulder – plaque) were more pronounced in high stenosis cases; in these cases, the plaque had significantly different texture compared to its shoulder and the adjacent wall.  

The plaque shoulder provides valuable information about the pathophysiology of atherosclerosis. Cardiac systole highlights better tissue texture properties. Texture variability along the atherosclerotic wall, which is indicative of tissue discontinuities, and proneness to rupture, can be quantitatively described with texture indices.

Golemati, S, Lehareas, S, Tsiaparas, N, Chatziioannou, A, Perrea, D, Nikita, K, Using Multiresolution Texture Analysis of B-mode Ultrasound Images to Identify Vulnerable Asymptomatic Plaque.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14019194.html