Abstract | OBJECTIVES: This study sought to examine the feasibility of in vivo detection of lipids in atherosclerotic plaque (AP) by ultrasound (US) thermal (or temporal) strain imaging (TSI). BACKGROUND: Intraplaque lipid content is thought to contribute to plaque stability. Lipid exhibits a distinctive physical characteristic of temperature-dependent US speed compared with water-bearing tissues. As tissue temperature changes, US radiofrequency (RF) echoes shift in time of flight, which produces an apparent strain (thermal or temporal strain [TS]). METHODS: US heating-imaging pulse sequences and transducers were designed and integrated into commercial US scanners for US-TSI of arterial segments. US-RF data were collected while gradually increasing tissue temperature. Phase-sensitive speckle tracking was applied to reconstruct TS maps coregistered to B-scans. Segments from injured atherosclerotic and uninjured nonatherosclerotic common femoral arteries (CFA) in cholesterol-fed New Zealand rabbits, and segments from control normal diet-fed rabbits (N =14) were scanned in vivo at different time points up to 12 weeks. RESULTS:
Lipid-rich atherosclerotic lesions exhibited distinct positive TS (+0.19 ± 0.08%) compared with that in nonatherosclerotic (-0.10 ± 0.13%) and control (-0.09 ± 0.09%) segments (p < 0.001). US-TSI enabled serial monitoring of lipids during atherosclerosis development. The coregistered set of morphological and compositional information of US-TSI showed good agreement with histology. CONCLUSIONS: US-TSI successfully detected and longitudinally monitored lipid progression in atherosclerotic CFA. US-TSI of relatively superficial arteries may be a modality that could be integrated into a commercial US system for noninvasive lipid detection in AP.
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Authors | Ahmed M Mahmoud, Debaditya Dutta, Linda Lavery, Douglas N Stephens, Flordeliza S Villanueva, Kang Kim |
Journal | Journal of the American College of Cardiology
(J Am Coll Cardiol)
Vol. 62
Issue 19
Pg. 1804-9
(Nov 05 2013)
ISSN: 1558-3597 [Electronic] United States |
PMID | 23916926
(Publication Type: Comparative Study, Journal Article, Research Support, N.I.H., Extramural)
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Copyright | Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved. |
Chemical References |
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Topics |
- Animals
- Diagnostic Imaging
(methods)
- Disease Models, Animal
- Image Processing, Computer-Assisted
- Lipids
(analysis)
- Male
- Plaque, Atherosclerotic
(chemistry, diagnostic imaging)
- Rabbits
- Radio Waves
- Reproducibility of Results
- Ultrasonography
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