Abstract:
:Intra-plaque hemorrhage (IPH) and lipid core, characteristics of rupture prone carotid plaques, are often visualized in vivo with MRI using T1 weighted gradient and spin echo, respectively. Increasing magnetic field strength may help to identify IPH and lipid core better. As a proof of concept, automatic segmentation of plaque components was performed with the Mahalanobis distance (MD) measure derived from image contrast from multicontrast MR images including inversion recovery spin echo and T1 weighted gradient echo with fat suppression. After MRI of nine formaldehyde-fixated autopsy specimens, the MDs and Euclidean Distances between plaque component intensities were calculated for each MR weighting. The distances from the carotid bifurcation and the size and shape of calcification spots were used as landmarks for coregistration of MRI and histology. MD between collagen/cell-rich area and IPH was largest with inversion recovery spin echo (4.2/9.3, respectively), between collagen/cell-rich area/foam cells and lipid core with T1 weighted gradient echo with fat suppression (26.9/38.2/4.6, respectively). The accuracy of detection of IPH, cell-rich area, and collagen increased when the MD classifier was used compared with the Euclidean Distance classifier. The enhanced conspicuity of lipid core and IPH in human carotid artery plaque, using ex vivo T1 weighted gradient echo with fat suppression and inversion recovery spin echo MRI and MD classifiers, demands further in vivo evaluation in patients.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
te Boekhorst BC,van 't Klooster R,Bovens SM,van de Kolk KW,Cramer MJ,van Oosterhout MF,Doevendans PA,van der Geest RJ,Pasterkamp G,van Echteld CJdoi
10.1002/mrm.23191subject
Has Abstractpub_date
2012-06-01 00:00:00pages
1764-75issue
6eissn
0740-3194issn
1522-2594journal_volume
67pub_type
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