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WE‐E‐134‐08: Characterization of Carotid Plaque with Histology and Quantitative Ultrasound
Author(s) -
Wang X,
Salamat S,
Varghese T,
Dempsey R
Publication year - 2013
Publication title -
medical physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.473
H-Index - 180
eISSN - 2473-4209
pISSN - 0094-2405
DOI - 10.1118/1.4815611
Subject(s) - histology , attenuation coefficient , ultrasound , attenuation , biomedical engineering , materials science , medicine , nuclear medicine , radiology , pathology , optics , physics
Purpose: To compare and correlate localization and registration of calcified, fibrous and lipid regions within heterogeneous plaque using histology and ultrasound quantitative imaging, and to better characterize carotid plaque. Methods: Atherosclerotic plaque excised after carotid endarterectomy, was imaged ex vivo using a VisualSonics Vevo 770 ultrasound system. Attenuation coefficient images were obtained from the three‐dimensional radiofrequency data collected and rendered into a 3D volume. Fixed plaque tissue was then longitudinally sectioned in increments of 5 um, and sections separated by 100 um were acquired. The thickness of each section of the sample was 5 um. Histopathology images were digitized using a PathScan Enabler IV. The two‐dimensional histology information obtained were registered using Matlab and reconstructed into a 3D volume. Different regions such as the lumen, calcified, fibrous and lipid region were segmented by a pathologist and digitally color‐coded into the 3D histology data. We then compared similar tissue types from the 3D histology volume to the estimated 3D attenuation coefficient using quantitative ultrasound methods. Results: Our results indicate that calcified, fibrous and lipid regions in the two volumes showed a good correlation. Calcified regions delineated on the histology volume correspond to the high attenuation coefficient region (2.48 dB/cm/MHz) in the 3D attenuation coefficient volume, while lipid regions tend to have lower attenuation coefficient values (1.47 dB/cm/MHz). Fibrous regions in histology, correlate to the lowest attenuation coefficient value (0.86 dB/cm/MHz). Conclusion: Most plaques are heterogeneous and difficult to characterize precisely. This work demonstrates a direct correlation between pathology and ultrasound quantitative imaging characterization of plaque. It provides a promising way for direct localization of plaque regions and structures, and for improved determination of plaque composition. This work was supported in part by NIH grants R21 EB010098‐02, R01 NS064034‐04, and 2R01 CA112192‐06.