Signal features of the atherosclerotic plaque at 3.0 Tesla versus 1.5 Tesla: impact on automatic classification.
OBJECTIVE
To investigate the impact of different field strengths on determining plaque composition with an automatic classifier.


METHODS
We applied a previously developed automatic classifier-the morphology enhanced probabilistic plaque segmentation (MEPPS) algorithm-to images from 20 subjects scanned at both 1.5 Tesla (T) and 3T. Average areas per slice of lipid-rich core, intraplaque hemorrhage, calcification, and fibrous tissue were recorded for each subject and field strength.


RESULTS
All measurements showed close agreement at the two field strengths, with correlation coefficients of 0.91, 0.93, 0.95, and 0.93, respectively. None of these measurements showed a statistically significant difference between field strengths in the average area per slice by a paired t-test, although calcification tended to be measured larger at 3T (P = 0.09).


CONCLUSIONS
Automated classification results using an identical algorithm at 1.5T and 3T produced highly similar results, suggesting that with this acquisition protocol, 3T signal characteristics of the atherosclerotic plaque are sufficiently similar to 1.5T characteristics for MEPPS to provide equivalent performance.
Kerwin
William S
WS
Department of Radiology, University of Washington, Seattle, Washington 98109, USA. bkerwin@u.washington.edu
Liu
Fei
F
Yarnykh
Vasily
V
Underhill
Hunter
H
Oikawa
Minako
M
Yu
Wei
W
Hatsukami
Thomas S
TS
Yuan
Chun
C
D000368:Aged; D000465:Algorithms; D050197:Atherosclerosis / Q000145:classification*; D016893:Carotid Stenosis / Q000473:pathology*; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D012815:Signal Processing, Computer-Assisted
D003287:Contrast Media; C064925:gadodiamide; D019786:Gadolinium DTPA