Chun Yuan1,2,3,4, Lee M. Mitsumori1,2,3,4, Marina S. Ferguson1,2,3,4, Nayak L. Polissar1,2,3,4, Denise R. Echelard1,2,3,4, Geraldo Ortiz1,2,3,4, Randy Small1,2,3,4, Joseph W. Davies1,2,3,4, William Kerwin1,2,3,4, Thomas S. Hatsukami1,2,3,4
1From the Departments of Radiology (C.Y., L.M.M., D.E., W.S.K., G.O.), Pathology (R.S.), and Surgery (J.W.D., T.S.H.), University of Washington; Marina Ferguson Inc (M.S.F.); The Mountain-Whisper-Light Statistical Consulting (N.L.P.); and Surgery and Perioperative Care, VA Puget Sound Health Care System (T.S.H.), Seattle, Wash.
2Marina Ferguson Inc (M.S.F.)
3Surgery and Perioperative Care, VA Puget Sound Health Care System (T.S.H.), Seattle, Wash.
4The Mountain-Whisper-Light Statistical Consulting (N.L.P.)
Tóm tắt
Background
High-resolution MRI has been shown to be capable of identifying plaque constituents, such as the necrotic core and intraplaque hemorrhage, in human carotid atherosclerosis. The purpose of this study was to evaluate differential contrast-weighted images, specifically a multispectral MR technique, to improve the accuracy of identifying the lipid-rich necrotic core and acute intraplaque hemorrhage in vivo.
Methods and Results
Eighteen patients scheduled for carotid endarterectomy underwent a preoperative carotid MRI examination in a 1.5-T GE Signa scanner using a protocol that generated 4 contrast weightings (T1, T2, proton density, and 3D time of flight). MR images of the vessel wall were examined for the presence of a lipid-rich necrotic core and/or intraplaque hemorrhage. Ninety cross sections were compared with matched histological sections of the excised specimen in a double-blinded fashion. Overall accuracy (95% CI) of multispectral MRI was 87% (80% to 94%), sensitivity was 85% (78% to 92%), and specificity was 92% (86% to 98%). There was good agreement between MRI and histological findings, with a value of κ=0.69 (0.53 to 0.85).
Conclusions
Multispectral MRI can identify the lipid-rich necrotic core in human carotid atherosclerosis in vivo with high sensitivity and specificity. This MRI technique provides a noninvasive tool to study the pathogenesis and natural history of carotid atherosclerosis. Furthermore, it will permit a direct assessment of the effect of pharmacological therapy, such as aggressive lipid lowering, on plaque lipid composition.
