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Title: Quantitative X-Ray Imaging of Intraplaque Hemorrhage in Aortas of ApoE-/-/LDL-/- Double Knockout Mice

Abstract

Objectives: To determine if hemorrhage into an arterial wall can be detected in CT images by virtue of the iron content. Materials and Methods: Aortas from male apoE-/-/LDL-/- mice (n = 31) were infused in situ with contrast agent, for micro-CT scanning and histology. Roentgen-opacities within the aortic walls were identified by histology and micro-x-ray fluorescence to be iron or calcium. Dual-energy scanning was performed at 2 energy levels using synchrotron-based micro-CT [(2 {mu}m)3 voxels, 16 and 20 keV] and 64-slice CT (0.4 x 0.4 x 0.6 mm voxels, 80 and 120 kVp). Results: Opacities were identified as hemorrhage-related clusters of multiple punctate deposits, containing both Fe (0.48 x 10-12 g/voxel) and Ca (3.18 x 10-2 g/voxel), or as isolated confluent accumulations of exclusively calcium. Subtraction of the dual-energy CT scans discriminated iron from calcium deposits. Conclusion: Detection and quantification of iron deposits in hemorrhaged atherosclerotic lesions is feasible by dual-energy CT imaging.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
960142
Report Number(s):
BNL-83128-2009-JA
Journal ID: ISSN 0020-9996; INVRAV; TRN: US201016%%1286
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Investigative Radiology; Journal Volume: 42; Journal Issue: 5
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; CALCIUM; DETECTION; ENERGY LEVELS; FLUORESCENCE; HEMORRHAGE; HISTOLOGY; IRON; MALES; MICE; national synchrotron light source

Citation Formats

Langheinrich,A., Michniewicz, A., Sedding, D., Lai, B., Jorgensen, S., Bohle, R., and Ritman, E. Quantitative X-Ray Imaging of Intraplaque Hemorrhage in Aortas of ApoE-/-/LDL-/- Double Knockout Mice. United States: N. p., 2007. Web. doi:10.1097/01.rli.0000258085.87952.ea.
Langheinrich,A., Michniewicz, A., Sedding, D., Lai, B., Jorgensen, S., Bohle, R., & Ritman, E. Quantitative X-Ray Imaging of Intraplaque Hemorrhage in Aortas of ApoE-/-/LDL-/- Double Knockout Mice. United States. doi:10.1097/01.rli.0000258085.87952.ea.
Langheinrich,A., Michniewicz, A., Sedding, D., Lai, B., Jorgensen, S., Bohle, R., and Ritman, E. Mon . "Quantitative X-Ray Imaging of Intraplaque Hemorrhage in Aortas of ApoE-/-/LDL-/- Double Knockout Mice". United States. doi:10.1097/01.rli.0000258085.87952.ea.
@article{osti_960142,
title = {Quantitative X-Ray Imaging of Intraplaque Hemorrhage in Aortas of ApoE-/-/LDL-/- Double Knockout Mice},
author = {Langheinrich,A. and Michniewicz, A. and Sedding, D. and Lai, B. and Jorgensen, S. and Bohle, R. and Ritman, E.},
abstractNote = {Objectives: To determine if hemorrhage into an arterial wall can be detected in CT images by virtue of the iron content. Materials and Methods: Aortas from male apoE-/-/LDL-/- mice (n = 31) were infused in situ with contrast agent, for micro-CT scanning and histology. Roentgen-opacities within the aortic walls were identified by histology and micro-x-ray fluorescence to be iron or calcium. Dual-energy scanning was performed at 2 energy levels using synchrotron-based micro-CT [(2 {mu}m)3 voxels, 16 and 20 keV] and 64-slice CT (0.4 x 0.4 x 0.6 mm voxels, 80 and 120 kVp). Results: Opacities were identified as hemorrhage-related clusters of multiple punctate deposits, containing both Fe (0.48 x 10-12 g/voxel) and Ca (3.18 x 10-2 g/voxel), or as isolated confluent accumulations of exclusively calcium. Subtraction of the dual-energy CT scans discriminated iron from calcium deposits. Conclusion: Detection and quantification of iron deposits in hemorrhaged atherosclerotic lesions is feasible by dual-energy CT imaging.},
doi = {10.1097/01.rli.0000258085.87952.ea},
journal = {Investigative Radiology},
number = 5,
volume = 42,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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