scholarly journals Quantitative susceptibility mapping improves the detection of calcified carotid vessels by multi-contrast MRI using computed tomography angiography as the reference standard

2021 ◽  
Author(s):  
Thanh D Nguyen ◽  
Yan Wen ◽  
Jingwen Du ◽  
Pascal Spincemaille ◽  
Yi Wang ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Carotid Artery ◽  
Vessel Wall ◽  
Carotid Arteries ◽  
Susceptibility Mapping ◽  
Reference Standard ◽  
Quantitative Susceptibility Mapping ◽  
Vessel Detection ◽  
Carotid Vessel Wall ◽  
Carotid Vessels

The objective of this study was to evaluate initial feasibility and improvement in the detection of calcified carotid arteries by including quantitative susceptibility mapping (QSM) in the carotid vessel wall multi-contrast MRI (mcMRI) protocol using CTA as the reference standard. In a pilot cohort of ten patients with significant carotid artery stenosis, calcified vessel detection by mcMRI achieved 64.7% sensitivity and 100% specificity. Adding QSM to mcMRI improved sensitivity to 100% while not affecting specificity.

scholarly journals Quantitative Susceptibility Mapping and Vessel Wall Imaging as Screening Tools to Detect Microbleed in Sentinel Headache

2020 ◽  
Vol 9 (4) ◽  
pp. 979
Author(s):  
Daizo Ishii ◽  
Daichi Nakagawa ◽  
Mario Zanaty ◽  
Jorge A. Roa ◽  
Sami Al Kasab ◽  
...  
Keyword(s):  
Predictive Value ◽  
Vessel Wall ◽  
Susceptibility Mapping ◽  
Vessel Wall Imaging ◽  
Screening Tools ◽  
Diagnostic Strategy ◽  
Quantitative Susceptibility Mapping ◽  
Post Contrast ◽  
Aneurysm Wall ◽  
Wall Imaging

Background: MR-quantitative susceptibility mapping (QSM) can identify microbleeds (MBs) in intracranial aneurysm (IA) wall associated with sentinel headache (SH) preceding subarachnoid hemorrhage. However, its use is limited, due to associated skull base bonny and air artifact. MR-vessel wall imaging (VWI) is not limited by such artifact and therefore could be an alternative to QSM. The purpose of this study was to investigate the correlation between QSM and VWI in detecting MBs and to help develop a diagnostic strategy for SH. Methods: We performed a prospective study of subjects with one or more unruptured IAs in our hospital. All subjects underwent evaluation using 3T-MRI for MR angiography (MRA), QSM, and pre- and post-contrast VWI of the IAs. Presence/absence of MBs detected by QSM was correlated with aneurysm wall enhancement (AWE) on VWI. Results: A total of 40 subjects harboring 51 unruptured IAs were enrolled in the study. MBs evident on the QSM sequence was detected in 12 (23.5%) IAs of 11 subjects. All these subjects had a history of severe headache suggestive of SH. AWE was detected in 22 (43.1%) IAs. Using positive QSM as a surrogate for MBs, the sensitivity, specificity, positive predictive value, and negative predictive value of AWE on VWI for detecting MBs were 91.7%, 71.8%, 50%, and 96.6%, respectively. Conclusions: Positive QSM findings strongly suggested the presence of MBs with SH, whereas, the lack of AWE on VWI can rule it out with a probability of 96.6%. If proven in a larger cohort, combining QSM and VWI could be an adjunctive tool to help diagnose SH, especially in cases with negative or non-diagnostic CT and lumbar puncture.

Results of Balloon Angioplasty in the Carotid Arteries

1996 ◽  
Vol 3 (1) ◽  
pp. 22-30 ◽  
Author(s):  
Reiner Kachel
Keyword(s):  
Computed Tomography ◽  
Carotid Artery ◽  
Percutaneous Transluminal Angioplasty ◽  
Carotid Arteries ◽  
Photon Emission ◽  
Transluminal Angioplasty ◽  
Emission Computed Tomography ◽  
Carotid Angioplasty ◽  
Carotid Stenoses ◽  
Percutaneous Transluminal

Purpose: To report the experiences to date with percutaneous transluminal angioplasty (PTA) of the carotid artery and other supra-aortic vessels. A new coaxial dilatation system for carotid angioplasty with temporary balloon occlusion to avoid cerebral embolization is presented. Methods: PTA was performed in 220 patients with 245 stenosed or occluded supra-aortic arteries; among these were 74 carotid stenoses in the proximal common (n = 5), distal common (n = 1), internal (n = 65), and external (n = 3) carotid arteries. Duplex and B-mode ultrasonography, computed tomography, magnetic resonance imaging, single-photon emission computed tomography, indium 111-labeled platelet scintigraphy, and/or angiography were used before and after PTA. Intravascular ultrasound imaging was also recently added for monitoring angioplasty results. Results: All patients but one with carotid lesions had symptoms of cerebrovascular insufficiency. Angioplasty was successful in 69 of the 74 carotid stenoses: proximal common (n = 5), distal common (n = 1), internal (n = 60), and external (n = 3). There were only 1 major (hemiparesis) and 2 minor complications. During the average 70-month observation period, restenosis has not occurred in any treated carotid artery. In a literature review of > 500 patients undergoing carotid angioplasty, the complication rate appears very low (mortality 0%; morbidity 2.1%) and comparable to that for carotid endarterectomy. Conclusions: Results of this review suggest that percutaneous transluminal angioplasty of the carotid artery is an effective alternative method to vascular surgery, particularly for patients with comorbidities that elevate the risks of surgery.

CD36 Mediated Reactive Oxygen Species Formation Contributes to Thrombosis.

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 1901-1901
Author(s):  
Wei Li ◽  
Maria Febbraio ◽  
Roy L. Silverstein
Keyword(s):  
Reactive Oxygen Species ◽  
Carotid Artery ◽  
Vessel Wall ◽  
Carotid Arteries ◽  
Reactive Oxygen ◽  
Radical Scavenger ◽  
Oxygen Species ◽  
Carotid Artery Injury ◽  
Artery Injury ◽  
Ros Formation

Abstract We previously showed that mice in which the CD36 gene was deleted had significantly prolonged time to form an occlusive thrombus in response to FeCl3-induced vascular injury than wild type (WT) mice. In other studies we and others have shown that CD36 promotes reactive oxygen species (ROS) formation in murine models of cerebral and cardiac ischemia. In this study, we examined the formation and roles of ROS in FeCl3-induced carotid artery injury and thrombosis using CD36 null and WT mice. Hydroethidine, a fluorescent superoxide indicator, was injected via the jugular vein and then carotid artery injury was induced in the contralateral artery by direct topical application of FeCl3 at concentrations of 7.5% or 12.5%. Fluorescence images were monitored with intravital microscopy. FeCl3 dose dependently induced significant accumulation of ROS in the vessel wall; however, the degree was significantly less in CD36 null mice than in WT mice exposed to the lower dose of FeCl3. Direct injection of Edavarone (1 mg/Kg body weight), a free radical scavenger, significantly elongated the time to thrombosis in WT mice. Thrombosis time was also increased in the CD36 null mice, but not to the same extent as WT. We also found fewer endothelial cell-derived microparticles (CD105 positive) in plasma of CD36 null mice 3 minutes after injury with the low dose of FeCl3. Immunoblots of lysates prepared from carotid arteries with thrombi or from untreated normal carotid arteries showed that levels of peroxiredoxin 2 (Prx 2), an antioxidant enzyme known to detoxify ROS, were lower in the thrombi formed from CD36 null mice, but higher in the normal vessel wall, suggesting that an anti-oxidative system may exist in the vessel wall of CD36 null mice. We conclude that CD36 plays a role in ROS formation during thrombosis and may also sensitize the vessel to injury induced by FeCl3. High Prx 2 expression in the vessel wall in CD36 null mice may contribute to the anti-oxidative effect observed in these mice.

Computational Fluid Dynamics of Carotid Arteries After Carotid Endarterectomy or Carotid Artery Stenting Based on Postoperative Patient-Specific Computed Tomography Angiography and Ultrasound Flow Data

Neurosurgery ◽  
2011 ◽  
Vol 68 (4) ◽  
pp. 1096-1101 ◽  
Author(s):  
Hitoshi Hayase ◽  
Koji Tokunaga ◽  
Toshio Nakayama ◽  
Kenji Sugiu ◽  
Ayumi Nishida ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computed Tomography ◽  
Computational Fluid Dynamics ◽  
Carotid Artery ◽  
Internal Carotid Artery ◽  
Carotid Arteries ◽  
Internal Carotid ◽  
Patient Specific ◽  
Flow Data ◽  
Simulation Results

Abstract BACKGROUND: There are significant differences in the postoperative morphological and hemodynamic conditions of the carotid arteries between carotid artery stenting (CAS) and endarterectomy (CEA). OBJECTIVE: To compare the postoperative rheological conditions after CAS with those after CEA with patch angioplasty (patch CEA) through the use of computational fluid dynamics (CFD) based on patient-specific data. METHODS: The rheological conditions in the carotid arteries were simulated in 2 patients after CAS and in 2 patients after patch CEA by CFD calculations. Three-dimensional reconstruction of the carotid arteries was performed with the images obtained with computed tomography angiography. The streamlines and wall shear stress (WSS) were calculated by a supercomputer. Adequate boundary conditions were determined by comparing the simulation results with ultrasound flow data. RESULTS: CFD was successfully calculated for all patients. The differences between the flow velocities of ultrasound data and those of the simulation results were limited. In the streamline analysis, the maximum flow velocities in the internal carotid artery after patch CEA were around two-thirds of those after CAS. Rotational slow flow was observed in the internal carotid artery bulb after patch CEA. WSS analysis found regional low WSS near the outer wall of the bulb. High WSS was observed at the distal end of the arteriotomy after patch CEA and at the residual stenosis after CAS. CONCLUSION: CFD of postoperative carotid arteries disclosed the differences in streamlines and WSS between CAS and patch CEA. CFD may allow us to obtain adequate rheological conditions conducive to achieving the best clinical results.

scholarly journals Carotid Artery Disease and Stroke: Assessing Risk with Vessel Wall MRI

2012 ◽  
Vol 2012 ◽  
pp. 1-13 ◽  
Author(s):  
William S. Kerwin
Keyword(s):  
Risk Factors ◽  
Carotid Artery ◽  
Vessel Wall ◽  
Carotid Arteries ◽  
Carotid Atherosclerosis ◽  
Carotid Artery Disease ◽  
Size Composition ◽  
Clinical Role ◽  
Additional Risk ◽  
Artery Disease

Although MRI is widely used to diagnose stenotic carotid arteries, it also detects characteristics of the atherosclerotic plaque itself, including its size, composition, and activity. These features are emerging as additional risk factors for stroke that can be feasibly acquired clinically. This paper summarizes the state of evidence for a clinical role for MRI of carotid atherosclerosis.

scholarly journals Quantitative susceptibility mapping of carotid arterial tissue ex vivo: assessing sensitivity to vessel microstructural composition

2021 ◽  
Author(s):  
Alan J. Stone ◽  
Brooke Tornifoglio ◽  
Robert D. Johnston ◽  
Karin Shmueli ◽  
Christian Kerskens ◽  
...  
Keyword(s):  
Magnetic Susceptibility ◽  
Carotid Arteries ◽  
Ex Vivo ◽  
Enzymatic Digestion ◽  
Susceptibility Mapping ◽  
Specific Marker ◽  
Quantitative Susceptibility Mapping ◽  
Healthy Human ◽  
Significant Difference ◽  
Arterial Tissue

AbstractPurposeTo characterise microstructural contributions to the magnetic susceptibility of carotid arteries.MethodArterial vessels were scanned using high resolution quantitative susceptibility mapping (QSM) at 7T. Models of vessel degradation were generated using ex vivo porcine carotid arteries that were subjected to several different enzymatic digestion treatments that selectively removed microstructural components (smooth muscle cells, collagen and elastin). Magnetic susceptibilities measured in these tissue models were compared to those in untreated (native) porcine arteries. Magnetic susceptibility measured in native porcine carotid arteries was further compared to the susceptibility of cadaveric human carotid arteries to investigate their similarity.ResultsThe magnetic susceptibility of native porcine vessels was diamagnetic (𝒳native = −0.1820ppm), with higher susceptibilities in all models of vessel degradation (𝒳elastin degraded = −0.0163ppm; 𝒳collagen degraded = −0.1158ppm; 𝒳decellularised = −0.1379ppm; 𝒳fixed native = −0.2199ppm). Magnetic susceptibility was significantly higher in collagen degraded compared to native porcine vessels (Tukey-Kramer, p<0.01) and between elastin degraded and all other models (including native, Tukey-Kramer, p<0.001). The susceptibility of fixed healthy human arterial tissue was diamagnetic and no significant difference was found between fixed human and fixed porcine arterial tissue susceptibilities (ANOVA, p>0.05).ConclusionsMagnetic susceptibility measured using QSM is sensitive to the microstructural composition of arterial vessels – most notably to collagen. The similarity of human and porcine arterial tissue susceptibility values provides a solid basis for translational studies. As vessel microstructure becomes disrupted during the onset and progression of carotid atherosclerosis, QSM has the potential to provide a sensitive and specific marker of vessel disease.

scholarly journals Digital Subtraction Angiogram (DSA) is Superior to Duplex Ultrasound (USD) in Diagnosis of Extracranial Carotid Stenosis - A Comparative Study

1970 ◽  
Vol 12 (1) ◽  
pp. 12-16
Author(s):  
Rajib Nayan Chowdhury ◽  
Kazi Mohibur Rahman ◽  
Shariff Uddin Khan ◽  
Rabindranath Sarker ◽  
Shahriar Nabi ◽  
...  
Keyword(s):  
Carotid Artery ◽  
Carotid Stenosis ◽  
Carotid Arteries ◽  
Duplex Ultrasound ◽  
Diagnostic Efficiency ◽  
Digital Subtraction ◽  
Key Word ◽  
Digital Subtraction Angiogram ◽  
Sensitivity Specificity ◽  
Carotid Vessels

This retrospective crossectional observational study was conducted in the department of Neurology, DMCH, Dhaka from December 2008 to December 2009. This study included a total of 40 patients, out of all, 35 suffered from nondisabling ischaemic stroke, other 5 had TIAs. Patients with ≥50% extracranial carotid stenosis on Duplex Ultrasound were then selected for DSA. DSA was done on these vessels and stenosis was measured using NASCET criteria. Results of USD and DSA were compared to determine the sensitivity, specificity and accuracy of Duplex Ultrasound (USD). ROC graph of RICA and LICA showed that most left and upper point of the curve lies at the level of 70% stenosis. At ≥70% stenosis of RICA and LICA the Sensitivity, Specificity and Accuracy were 91.2%, 50%, 85% and 86.83%, 50%, 85% respectively. This level of diagnostic efficiency of USD is less than that of DSA of carotid arteries. Study revealed that USD underestimates or overestimates degree of carotid stenosis, and DSA is safe and effective in determining stenosis. So before taking any decision to intervene in the form of Carotid endarterectomy or carotid artery stenting, it would be wise to do Digital Subtraction Angiogram of carotid vessels. Key word: Digital Subtraction Angiogram; Duplex Ultrasound; carotid vessels. DOI: 10.3329/jom.v12i1.6926J Medicine 2011; 12 : 12-16

Sign in / Sign up

Export Citation Format

Share Document