Vulnerable plaque detection by 3.0 tesla magnetic resonance imaging.
OBJECTIVE
A clinical case report is presented on a 76-year-old man who volunteered for a 3.0 T magnetic resonance (MR) carotid protocol. The subject was referred for carotid endarterectomy and histology was performed on the ex vivo specimen and compared with the in vivo images.


METHODS
The 3.0 and 1.5 T (obtained for comparison) MR protocol consisted of 2-dimensional (2D) and 3-dimensional (3D) multicontrast bright and black blood imaging for detecting the lumen and vessel wall.


RESULTS
The combination of multicontrast black blood transverse images and the 3D time of flight transverse images provided visualization of a narrowed internal carotid artery lumen 4 mm above of the bifurcation and the presence of a complex atherosclerotic plaque containing a large lipid pool, calcification, and intact fibrous cap. Quantitative comparisons including vessel lumen and plaque area, signal-to-noise (SNR) and contrast-to-noise (CNR) ratios were obtained for 1.5 and 3.0 T image data. Plaque composition was verified with histology. Macrophages were also detected in the shoulders of the plaque as demonstrated by CD68 staining and corresponded with a small hyperintense area in the T2W images at 3.0 T, but not observed in comparable 1.5 T images.


CONCLUSIONS
High field 3.0 T multicontrast MRI of atherosclerotic plaque has been validated with histology comparison and provides improved detection of complex atherosclerotic plaque with increased SNR and CNR compared with 1.5 T. Further studies validating contrast mechanisms of plaque at 3.0 T are required, but atherosclerotic plaque imaging has clear benefit from application at the higher magnetic field strength.
Cury
Ricardo C
RC
Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA.
Houser
Stuart L
SL
Furie
Karen L
KL
Stone
James R
JR
Ogilvy
Christopher S
CS
Sherwood
Jane B
JB
Muller
James E
JE
Brady
Thomas J
TJ
Hinton
Denise P
DP
D000368:Aged; D002343:Carotid Artery, Internal / Q000473:pathology*; D016893:Carotid Stenosis / Q000175:diagnosis*; D006801:Humans; D007089:Image Enhancement; D008279:Magnetic Resonance Imaging / Q000379:methods*