MRI changes of component and morphology in the internal carotid vulnerable plaque / 中华放射学杂志

ABSTRACT

Objective To investigate the changes of component and morphology in internal carotid vulnerable plaque,for helping to make clinical intervention strategy individually. Methods A total of 47 patients with internal carotid vulnerable plaques and primary hypertension underwent 2 high-resolution and multi-contrast MRI scans, from March 2008 to April 2014 were retrospectively reviewed. At baseline, the plaque was mainly located at the proximal internal carotid artery,and maximum plaque thickness ≥1.5 mm with intraplaque hemorrhage(IPH)and(or)thin or ruptured fibrous cap.Interscan interval was 0.5 years and above. Patients with carotid occlusion or surgery were excluded. Morphological measurements included maximum plaque thickness, maximum plaque area and cross-sectional vessel area (CSVA) on the level of plaque with maximum thickness. The paired-samples t test was performed to compare the difference of plaque morphology between baseline and follow-up carotid MRI.Results The interscan interval was 1.83 (1.59,1.99)years for 47 internal carotid vulnerable plaques.One case(interscan interval 2.16 years)showed IPH within those 11 plaques without IPH at baseline,and one case(interscan interval 1.42 years)had new incident IPH within those 36 plaques with IPH at baseline. Maximum plaque thickness increased significantly from(3.94±1.44)mm to(4.24±1.68)mm(t=2.30,P<0.05)by 5.14%(-3.83,11.34)% per year. Maximum plaque area increased significantly from(49.19±21.15)mm2to(56.03±24.91)mm2(t=3.87,P<0.01)by 6.67%(-2.26,19.60)% per year.CSVA increased significantly from(66.22±27.51)mm2to(73.68±31.47)mm2(t=4.08,P<0.01)by 5.18%(-1.63,12.34)% per year.Conclusion The progression of component,burden and outer remodeling in the internal carotid vulnerable plaque may be faster in hypertension, therefore reasonable intervention strategy and regular follow-up carotid MRI should be performed.