Carotid artery stenosis with a high-intensity signal plaque on time-of-flight magnetic resonance angiography and association with evidence of intraplaque hypoxia

2016 ◽  
Vol 126 (6) ◽  
pp. 1873-1878 ◽  
Author(s):  
Atsushi Ogata ◽  
Masatou Kawashima ◽  
Tomihiro Wakamiya ◽  
Masashi Nishihara ◽  
Jun Masuoka ◽  
...  

OBJECTIVEHypoxia induces angiogenesis and plays a major role in the progression of carotid plaques. During carotid intervention, plaques with high-intensity signals on time-of-flight (TOF) magnetic resonance angiography (MRA) often cause ischemic stroke and embolic complications. However, the role of intraplaque hypoxia before carotid endarterectomy (CEA) and carotid artery stenting is not presently understood. In this study the authors aimed to investigate the relationship between intraplaque hypoxia and MRA findings.METHODSNineteen consecutive patients with 20 carotid artery stenoses who underwent CEA at Saga University Hospital between August 2008 and December 2014 were enrolled in the study. The expressions of hypoxia-inducible transcription factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) were analyzed by immunohistochemical analysis. In addition, the relationship between the findings on TOF MRA and pathology for the carotid plaques was analyzed.RESULTSHigh-intensity plaques on TOF MRA showed higher expression levels of HIF-1α (p = 0.015) and VEGF (p = 0.007) compared with isointensity plaques. The rate of intraplaque hemorrhage (IPH) on TOF MRA was also significantly higher in the high-intensity plaques than in the isointensity plaques (p = 0.024). Finally, the mean number of neovessels was significantly higher in those without plaque hemorrhage than in those with plaque hemorrhage (p = 0.010).CONCLUSIONSPlaques with high-intensity signals on TOF MRA were associated with IPH and evidence of intraplaque hypoxia. This fact may represent an opportunity to establish novel therapeutic agents targeting intraplaque hypoxia.


2020 ◽  
Vol 21 (6) ◽  
pp. 1980 ◽  
Author(s):  
Atsushi Ogata ◽  
Tomihiro Wakamiya ◽  
Masashi Nishihara ◽  
Tatsuya Tanaka ◽  
Taichiro Mizokami ◽  
...  

(1) Background: Pericytes are involved in intraplaque neovascularization of advanced and complicated atherosclerotic lesions. However, the role of pericytes in human carotid plaques is unclear. An unstable carotid plaque that shows high-intensity signals on time-of-flight (TOF) magnetic resonance angiography (MRA) is often a cause of ischemic stroke. The aim of the present study is to examine the relationship between the pericytes in intraplaque neovessels and MRA findings. (2) Methods: A total of 46 patients with 49 carotid artery stenoses who underwent carotid endarterectomy at our hospitals were enrolled. The patients with carotid plaques that were histopathologically evaluated were retrospectively analyzed. Intraplaque hemorrhage was evaluated using glycophorin A staining, and intraplaque neovessels were evaluated using CD34 (Cluster of differentiation) stain as an endothelial cell marker or NG2 (Neuron-glial antigen 2) and CD146 stains as pericyte markers. Additionally, the relationships between the TOF-MRA findings and the carotid plaque pathologies were evaluated. (3) Results: Of the 49 stenoses, 28 had high-intensity signals (TOF-HIS group) and 21 had iso-intensity signals (TOF-IIS group) on TOF-MRA. The density of the CD34-positive neovessels was equivalent in both groups. However, the NG2- and CD146-positive neovessels had significantly higher densities in the TOF-HIS group than in the TOF-IIS group. (4) Conclusion: The presence of a high-intensity signal on TOF-MRA in carotid plaques was associated with intraplaque hemorrhage and few pericytes in intraplaque neovessels. These findings may contribute to the development of new therapeutic strategies focusing on pericytes.



Stroke ◽  
2015 ◽  
Vol 46 (suppl_1) ◽  
Author(s):  
Kiyofumi Yamada ◽  
Masanori Kawasaki ◽  
Shinichi Yoshimura ◽  
Shigehiro Nakahara ◽  
Yoshikazu Sato

Background: Carotid artery stenosis is one of the major causes of ischemic strokes. Carotid intraplaque hemorrhage (IPH) has been associated with accelerated plaque growth, luminal narrowing and development of symptomatic events. Maximum intensity projection images are easily reformatted from four to five minute, routine, clinical TOF sequences. The aim of this study was to evaluate the relationships between high intensity signal (HIS) in carotid plaques on MIP images detected by routine three dimensional magnetic resonance imaging (3D-TOF MRA) and ischemic strokes. Materials and Methods: Sixty patients with carotid stenosis ≥ 50% (North American Symptomatic Carotid Endarterectomy Trial criteria) were included. Carotid IPH was defined as the presence of HIS in carotid plaques on MIP images detected by 3DTOF MRA using the criteria previously we reported. We analyzed the relation between the presence of HIS in the plaques and prior ischemic strokes defined as ischemic lesions on diffusion weighed images of the brain. Results: HISs in carotid plaque were present in 27 (44%) of 61 carotid arteries in 60 patients. Prior ipsilateral ischemic strokes occurred more frequently in HIS positive group (17 of 27, 63%) than HIS negative group (3 of 34; 9%) [p<0.001]. In multivariate logistic regression analysis, HIS was the only independent predictor of prior ischemic strokes after being adjusted by age, cardiovascular risk factors, degree of stenosis and history of ischemic heart disease [Odds ratio: 23.0 (95%CI: 5.1 - 103.1), p<0.001]. Conclusions: HISs in carotid plaques on 3DTOF-MRA MIP images are the only independent determinant of prior ischemic strokes, and they can potentially provide a reliable risk stratification of carotid plaques.



2021 ◽  
pp. 1-6
Author(s):  
Keisuke Tokunaga ◽  
So Tokunaga ◽  
Kenta Hara ◽  
Masahiro Yasaka ◽  
Yasushi Okada ◽  
...  

OBJECTIVE To test the hypothesis that intraplaque hemorrhage is a predictor of restenosis after carotid artery stenting (CAS), the association between intraplaque high-intensity signal (HIS) on time-of-flight MR angiography (TOF-MRA), as a marker of intraplaque hemorrhage, and restenosis after CAS was assessed in the present observational study. METHODS Consecutive patients who underwent initial CAS for atherosclerotic stenosis in the cervical internal carotid artery in the authors’ department were enrolled. Of these, patients without preprocedural cervical TOF-MRA were excluded. Outcome measures were ≥ 50% restenosis, defined as a peak systolic velocity of > 1.3 m/sec; or occlusion and ≥ 70% restenosis, defined as a peak systolic velocity of > 2.1 m/sec; or occlusion on carotid duplex ultrasound. RESULTS Of 230 consecutive patients who underwent initial CAS, 22 without preprocedural cervical TOF-MRA were excluded. Of the remaining 208 patients (mean age 73 years; 33 women), 46 had intraplaque HIS. Ultrasound follow-up was not performed in 4 patients. The median follow-up duration was 3.2 years (interquartile range 1.7–5.1 years). During the follow-up period, 102 patients had ≥ 50% restenosis and 36 had ≥ 70% restenosis. Intraplaque HIS was significantly associated with increased risk of ≥ 50% restenosis (adjusted hazard ratio 2.18; 95% CI 1.28–3.68) and ≥ 70% restenosis (adjusted hazard ratio 3.12; 95% CI 1.32–7.52). CONCLUSIONS Intraplaque HIS on TOF-MRA was associated with increased risk of restenosis after CAS. The present results indicate that intraplaque hemorrhage is a predictor of restenosis after CAS.



Stroke ◽  
2011 ◽  
Vol 42 (11) ◽  
pp. 3132-3137 ◽  
Author(s):  
Shinichi Yoshimura ◽  
Kiyofumi Yamada ◽  
Masanori Kawasaki ◽  
Takahiko Asano ◽  
Masayuki Kanematsu ◽  
...  


2021 ◽  
Vol 84 (2) ◽  
pp. 119-123
Author(s):  
Mami Ishikawa ◽  
Satoshi Terao ◽  
Hiroshi Kagami ◽  
Makoto Inaba ◽  
Heiji Naritaka

<b><i>Background:</i></b> Patients with moyamoya disease often develop cerebral infarction and hemorrhage, but the ischemic and hemorrhagic subtypes are difficult to diagnose prior to disease onset. We aimed to differentiate the ischemic and hemorrhagic subtypes of moyamoya disease by analyzing the intralateral and perilateral ventricular arteries on the original axial magnetic resonance angiography (MRA) images. <b><i>Methods:</i></b> We retrospectively analyzed the intralateral and perilateral ventricular arteries on the original axial time-of-flight (TOF)-MRA images of 18 patients with hemorrhagic moyamoya disease, 25 patients with ischemic moyamoya disease, and 22 control patients with unruptured aneurysms. <b><i>Results:</i></b> There were significantly more intralateral and perilateral ventricular arteries on the original axial MRA images in the patients with hemorrhagic moyamoya disease (6.3 ± 2.7) than in those with ischemic moyamoya disease (0.8 ± 0.9) and those with unruptured aneurysms (0.4 ± 0.8). <b><i>Conclusion:</i></b> The intralateral and perilateral ventricular arteries on the original axial TOF-MRA images might suggest the hemorrhagic type of moyamoya disease prior to onset.



2021 ◽  
Vol 8 ◽  
Author(s):  
Feifei Zhang ◽  
Yuncai Ran ◽  
Ming Zhu ◽  
Xiaowen Lei ◽  
Junxia Niu ◽  
...  

Background and Purpose: 3D pointwise encoding time reduction magnetic resonance angiography (PETRA-MRA) is a promising non-contrast magnetic resonance angiography (MRA) technique for intracranial stenosis assessment but it has not been adequately validated against digital subtraction angiography (DSA) relative to 3D-time-of-flight (3D-TOF) MRA. The aim of this study was to compare PETRA-MRA and 3D-TOF-MRA using DSA as the reference standard for intracranial stenosis assessment before and after angioplasty and stenting in patients with middle cerebral artery (MCA) stenosis.Materials and Methods: Sixty-two patients with MCA stenosis (age 53 ± 12 years, 43 males) underwent MRA and DSA within a week for pre-intervention evaluation and 32 of them had intracranial angioplasty and stenting performed. The MRAs' image quality, flow visualization within the stents, and susceptibility artifact were graded on a 1–4 scale (1 = poor, 4 = excellent) independently by three radiologists. The degree of stenosis was measured by two radiologists independently on DSA and MRAs.Results: There was an excellent inter-observer agreement for stenosis assessment on PETRA-MRA, 3D-TOF-MRA, and DSA (ICCs &gt; 0.90). For pre-intervention evaluation, PETRA-MRA had better image quality than 3D-TOF-MRA (3.87 ± 0.34 vs. 3.38 ± 0.65, P &lt; 0.001), and PETRA-MRA had better agreement with DSA for stenosis measurements compared to 3D-TOF-MRA (r = 0.96 vs. r = 0.85). For post-intervention evaluation, PETRA-MRA had better image quality than 3D-TOF-MRA for in-stent flow visualization and susceptibility artifacts (3.34 ± 0.60 vs. 1.50 ± 0.76, P &lt; 0.001; 3.31 ± 0.64 vs. 1.41 ± 0.61, P &lt; 0.001, respectively), and better agreement with DSA for stenosis measurements than 3D-TOF-MRA (r = 0.90 vs. r = 0.26). 3D-TOF-MRA significantly overestimated the stenosis post-stenting compared to DSA (84.9 ± 19.7 vs. 39.3 ± 13.6%, p &lt; 0.001) while PETRA-MRA didn't (40.6 ± 13.7 vs. 39.3 ± 13.6%, p = 0.18).Conclusions: PETRA-MRA is accurate and reproducible for quantifying MCA stenosis both pre- and post-stenting compared with DSA and performs better than 3D-TOF-MRA.





Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Kiyofumi Yamada ◽  
Masanori Kawasaki ◽  
Shigehiro Nakahara ◽  
Yoshikazu Sato ◽  
Kazutaka Uchida ◽  
...  

Background: Carotid artery stenosis is one of the major causes of ischemic strokes. However, degree of stenosis is not always correlated with frequency of ischemic strokes. Recently, it was reported that carotid intraplaque hemorrhage (IPH) was associated with accelerated plaque growth, luminal narrowing and development of symptomatic events. Maximum intensity projection (MIP) images are easily reformatted within from 5 minute, routine time-of-flight (TOF) sequences. The aim of this study was to evaluate the relationships between high intensity signal (HIS) in the carotid plaques on MIP images detected by routine three-dimensional TOF magnetic resonance angiography (3D-TOF MRA) and ischemic strokes. Materials and Methods: One hundred fifty two patients with low-grade carotid artery stenosis (North American Symptomatic Carotid Endarterectomy Trial criteria: 30% - 49%) were included. IPH was defined as the presence of HIS in the carotid plaques on MIP images of 3D-TOF MRA using the previously reported criteria. We analyzed the relationship between the presence of HIS in the plaques and prior ischemic strokes defined as ischemic lesions on diffusion weighed images of the brain. Results: HIS in the carotid plaque was present in 56 (37%) of 152 carotid arteries. Prior ipsilateral ischemic strokes were observed more frequently in HIS-positive group (12 of 56, 21.4%) than HIS-negative group (1 of 34: 2.9%) [p<0.001]. In multivariate logistic regression analysis, HIS (Odds ratio: 77.7, 95%CI: 6.4 - 944.0, p<0.001) and diabetes mellitus type 2 (odds ratio: 10.45, 95%CI: 1.6 - 67.9, p=0.014) were independent determinants of prior ischemic strokes after adjustment for age. Conclusions: HIS in the carotid plaques on MIP images of 3D-TOF MRA was an independent determinant of prior ischemic stroke in patients with low-grade carotid artery stenosis, and this finding may provide a reliable risk stratification of future stroke in patients with low-grade carotid artery stenosis.



Sign in / Sign up

Export Citation Format

Share Document