Introduction: Early restenosis after carotid endarterectomy (CEA) is thought to be a result from neointimal hyperplasia. However, little is known about preoperative Magnetic Resonance (MR) characteristics of restenotic plaques. We investigated the association between preoperative MR plaque imaging and restenosis after CEA.
Methods: Between 2003 and 2010, 113 carotid arteries of 108 patients undergoing CEA were included. We used 2D gradient-echo black-blood T1-weighted imaging at 1.5T for the evaluation of plaque characteristics. We estimated relative overall signal intensity of plaque components. Plaques that had signal intensity of T1roSI?1.25 were defined as vulnerable plaque. The patients underwent MR plaque imaging before surgery. Patency after CEA was assessed with ultrasonography, MR angiography, and digital subtraction angiography. Restenosis was defined as recurrent luminal narrowing?50% in either modality at the endarterectomy site. Association between the occurrence of restenosis after CEA and preoperative MR plaque imaging was investigated.
Results: Thirteen arteries of 13 patients were lost to follow-up within 1 year (2 arteries were occluded within 7 days after operation, 3 patients were died within 1 year). 100 arteries of 95 patients were included in the study. Recurrent carotid stenosis was observed in 9 arteries, 8 of which were performed preoperative MR plaque imaging, and their mean T1roSI was 1.17±0.17. There were 91 arteries without restenosis after CEA, 76 of which were performed preoperative MR plaque imaging, and their mean T1roSI was 1.32±0.22. Preoperative T1roSI of restenotic arteries was lower than that of non-restenotic arteries, but the difference was not statistically significant (95% CI, -0.02-0.31; P=.080).
Plaque MRI after restenosis was taken in 4 arteries. Their mean T1roSI was 0.98±0.10, significantly lower than that of all preoperative plaques.
Conclusions: Preoperative T1-weighted images of restenotic plaque seemed lower than that of non-restenotic plaques. Further investigation will confirm the preoperative MR characteristics of restenosis after CEA.
Patient Care: This work will help to stratify the patient at risk of restenosis after CEA.
Learning Objectives: By the conclusion of this session, participants should be able to identify the characteristics of carotid plaques in restenosis after CEA.