Magnetic Resonance Imaging and Clinical Factors Associated With Ischemic Stroke in Patients Suspected of Cervical Artery Dissection

Abstract

Background and Purpose: Cervical artery dissection is a major cause of ischemic stroke in the young and presents with various imaging findings including stenosis and intramural hematoma (IMH). Our goal was to determine the relative contribution of lumen findings and IMH to acute ischemic stroke, and if a heavily T1-weighted sequence could more reliably detect IMH. Methods: IRB approval was obtained for this retrospective study of 254 patients undergoing MRI/MRA for suspected dissection. Imaging included standard turbo spin echo (TSE) T1-fat saturation (T1FS) and heavily T1-weighted flow-suppressed Magnetization Prepared Rapid Acquisition Gradient-recalled Echo (MPRAGE) sequences. Subjects with stents (1) or atherosclerotic disease (26) were excluded, leaving 227 subjects. Kappa analysis was used to determine IMH interrater reliability on MPRAGE and T1FS in 4 vessels per subject. Lumen findings, cardiovascular risk factors, medications, and non-dissection stroke sources were recorded. Mixed effects multivariate Poisson regression was used to determine the prevalence ratio (PR) of each factor with acute ischemic stroke, accounting for 4 vessels per patient with backwards elimination to a threshold p-value of 0.10. Results: Patients were 41.9% male, mean age of 47.3±16.6 years, with 114 dissections and 107 strokes. IMH interrater reliability was significantly higher for MPRAGE (kappa=0.83, 95%CI: 0.78–0.86) versus T1FS (0.58, 95%CI: 0.57–0.68). The final acute stroke prediction model included MPRAGE-detected IMH (PR=2.0, 95%CI: 1.1–3.9, p=0.034), stenosis, pseudoaneurysm, male gender, current smoking, and non-dissection stroke sources. The final model had high discrimination for acute stroke (AUC=0.902, 95%CI: 0.872–0.932), compared to models without stenosis (0.861, 95%CI: 0.821–0.902), and without stenosis and IMH (0.831, 95%CI: 0.783–0.879). All three models were significantly different at p<0.05. Conclusions: Along with stenosis, IMH detection significantly contributed to acute ischemic stroke etiology in patients with suspected cervical artery dissection. In addition, IMH detection can be made more reliable with heavily T1-weighted sequences.

The etiologies and prognosis associated with spinal cord infarction

“…Both CT angiography and MR angiography can effectively visualize vertebral artery dissection; however, CT angiography can be performed rapidly, and it allows simple reconstruction of the dissection artery in an acute setting . Recently, it was shown that using the heavily T1‐weighted sequence on MRI could increase the reliability of detection of intramural hematoma compared with using the T1‐fat saturation method, which could improve the accuracy of vertebral artery dissection diagnosis . In aortic dissection, multi‐detector row CT is the modality of choice for imaging acute aortic syndrome with a sensitivity and specificity approaching 100% …”

The Added Value of Vessel Wall MRI in the Detection of Intraluminal Thrombus in Patients Suspected of Craniocervical Artery Dissection

“…The intimal flap and irregular surface of the vessel wall may reflect endothelial damage, which activates thrombus formation and may ultimately lead to occlusion or embolism [ 31 ]. Ischemic stroke in patients with CCAD is frequently associated with signs of thrombotic mechanisms observed upon imaging [ 6 , 32 ]. Coppenrath et al [ 33 ] demonstrated that intraluminal contrast enhancement on 2D-T1-weighted images revealed intraluminal thrombus formation and was strongly correlated with territorial ischemic stroke with an odds ratio of 32.0 (95% CI: 3.6-281) in 33 patients with spontaneous cervical artery dissection.…”

Vertebrobasilar and internal carotid arteries dissection in 188 patients

“…Among the vascular risk factors, hypertension is most often present (26.7%-68.9%), as well as hyperlipidemia (17-51%) and smoking (12.8-52.0%), but less frequently diabetes (2.0-24.9%) and migraine (up to 21.2%) [1,41,50,51,54,57,58,[68][69][70][71]. Our findings are within this range, except hypertension, which was more frequent due to older age of our patients (Tables 1 and 4).…”

“…It manly comprises ischemic stroke (IS) of the brain or spinal cord, TIA, retinal infarcts, amaurosis fugax, and certain autonomic or cranial nerves [8,17,36,41,43,62,71,72,76,81,98,103,104]. IS of the brain is present in 30-64% of patients, either as a larger ischemic area or, rarely, as small lacunar lesions [36,69].…”