- Improved White Matter Cerebrovascular Reactivity after Revascularization in Patients with Steno-Occlusive Disease
Thirty-five patients with steno-occlusive disease (Moyamoya disease [n = 24], Moyamoya syndrome [n = 3], atherosclerosis [n = 6], vasculitis [n = 1], and idiopathic stenosis [n = 1]) who underwent unilateral brain revascularization using a direct superficial temporal artery–to-MCA bypass were evaluated. WM cerebrovascular reactivity was measured preoperatively and postoperatively using BOLD MR imaging during iso-oxic hypercapnic changes in end-tidal carbon dioxide. WM cerebrovascular reactivity significantly improved after direct unilateral superficial temporal artery–to-MCA bypass in the revascularized hemisphere in the MCA territory and in the anterior cerebral artery territory.
- MRI Quantitative T2* Mapping to Predict Dominant Composition of In Vitro Thrombus
Thirty-five thrombus analogs of different compositions were scanned with an MR imaging quantitative T2* mapping sequence. Two radiologists, blinded to thrombus composition, measured the thrombus-T2* relaxation time twice, at an interval of 2 weeks. Quantitative histologic evaluations of red blood cell content were performed. Inter- and intraobserver reproducibility of the thrombus-T2* relaxation time was assessed by calculating intraclass correlation coefficients. MR imaging quantitative T2* mapping can reliably identify the thrombus red blood cell content in vitro. This fast, easy-to-use sequence could be implemented in routine practice.
- Two-Layered Susceptibility Vessel Sign and High Overestimation Ratio on MRI Are Predictive of Cardioembolic Stroke
Two characteristics of the susceptibility vessel sign, overestimation ratio (overR), a quantitative evaluation of the susceptibility vessel sign, and the 2-layered susceptibility vessel sign (TL-SVS), were reported to predict cardioembolic stroke. These 2 biomarkers, on 1.5T or 3T systems (159 and 101 patients, respectively), demonstrated high specificity (0.77 at 1.5T and 1 at 3T) and their simultaneous presence is highly associated with cardioembolism.