Grading Of Carotid Artery Stenosis Research Articles

Prospective Analysis of Prevalence of Carotid Artery Disease and Neurological Outcomes After CABG in Patients with Significant Carotid Artery Disease

CABG surgery is the utmost frequently performed major cardiovascular operation. Carotid artery stenosis is present-day in 6% to 8% of all patients undergoing CABG and is related with an increased risk of stroke during and after CABG. It is well recognized that the presence of carotid artery stenosis is a significant forecaster of poor consequences in patients undergoing coronary bypass graft surgery (CABG). The incidence of coexisting coronary and carotid artery disease varies between 2% and 14% and approximately 8% of patients undergoing CABG have a significant stenosis in an extra cranial carotid artery. The stated occurrence of carotid artery disease in patients experiencing cardiac surgery has diverse from 2 to 22%, with an average of 8% increasing with age. This prospective observational study was conducted in patients undergoing off-pump coronary artery bypass grafting with carotid artery stenosis from May 2015 to Feb 2017. A total of 2126 patients were observed and classified to three groups based on the grade of carotid artery stenosis in which 221 patients (group A) were Symptomatic or (asymptomatic with ≥ 70% carotid stenosis, unilateral or bilateral), 583 patients (group B) 70% carotid stenosis group (p=0.0004). In our study 6 patients (2.71%) presented with stroke in group A. The frequency in group B and C were 0.69% and 0.08% respectively, and were statistically (p=<0.001). Most of the patients in group A had experienced concomitment endarctectomy of carotid with (4.52%) compared to group B and C (0.17% and 0%). The occurrence of previous history of stroke/TIA was higher in group A compared to other groups (p<0.001) [Previous h/o stroke was seen in 74 (6.3%), 32 (5.4%) and 29 (2.19%) patients in respective groups]. Previous history of stroke has proved a vital role in decisive the outcome of these patients. Higher grade of Carotid stenosis doesn’t affect mortality, ICU stay and the need for dialysis as proved in this study.

Neutrophil Gelatinase Associated Lipocalin (NGAL) for Identification of Unstable Plaques in Patients with Asymptomatic Carotid Stenosis

Neutrophil gelatinase associated lipocalin (NGAL) and matrix metalloproteinase (MMP)-9/NGAL complex were investigated in asymptomatic patients with carotid artery stenosis including gender specific differences aiming at vulnerable plaques prone to embolisation. Serum NGAL and MMP-9/NGAL levels were analysed in 83 patients with asymptomatic carotid artery stenosis. Pre-operative ultrasound and post-endarterectomy histology of carotid atherosclerotic lesions were evaluated. Patients with vulnerable plaques, as determined by ultrasound (plaques with decreased echogenicity) and histological analysis (type VI according to the classification of the American Heart Association), displayed the highest levels of NGAL and MMP-9/NGAL complex (p=.0003 and p=.0078, respectively). Grade VI plaques were primarily detected in patients with "soft" plaques (12 type VI plaques in 25 patients), but also in patients with mixed (four of 19) and calcified (three of 39) plaques according to ultrasound. Higher grade carotid artery stenosis (≥90%) was not associated with elevated NGAL levels. The receiver operating characteristic curve analysis detecting grade VI lesions yields an area under the curve (AUC)=0.85, with respect to soft plaque on ultrasound the AUC=0.86. There were no gender specific differences in levels of NGAL 80.9 (37.7) ng/mL in women vs. 76.7 (36.3) ng/mL in men, p=.607) nor of MMP-9/NGAL 33.0 (18.2-55.5) ng/mL in women vs. 36.7 (20.2-54.0) ng/mL in men, p=.969. Likewise, there were no gender associated differences in vulnerable plaque characteristics: either for grade VI plaques (17.9% vs. 27.3%, p=.582) or for the presence of soft plaques as evaluated by ultrasound (35.9% vs. 25%, p=.503). Circulating NGAL and MMP-9/NGAL are significantly increased in asymptomatic patients with vulnerable carotid atherosclerotic plaques independent of gender. Accordingly, serum NGAL may be proposed as a valuable biomarker for the detection of unstable carotid plaques in asymptomatic patients, who can then be selected for early carotid endarterectomy or stenting.

Dynamics of brain perfusion and cognitive performance in revascularization of carotid artery stenosis.

IntroductionThere is evidence suggesting a detrimental effect of asymptomatic carotid artery stenosis on cognitive function even in the absence of ischemic cerebral lesions. Hypoperfusion has been suggested as pathophysiological mechanism causing cognitive impairment. We aimed to assess cognitive performance and cerebral perfusion changes in patients with carotid artery stenosis without ischemic lesions by arterial spin labeling (ASL) and contrast enhanced (CE) perfusion MRI before and after revascularization therapy.Methods17 asymptomatic patients with unilateral high-grade (≥70%) carotid artery stenosis without evidence of structural brain lesions underwent ASL and CE perfusion MRI and cognitive testing (MMSE, DemTect, Clock-Drawing Test, Trail-Making Test, Stroop Test) before and 6–8 weeks after revascularization therapy by endarterectomy or stenting. Multiparametric perfusion maps (ASL: cerebral blood flow (ASL-CBF), bolus arrival time (ASL-BAT); CE: cerebral blood flow (CE-CBF), mean transit time (CE-MTT), cerebral blood volume (CE-CBV)) were calculated and analyzed by vascular territory. Relative perfusion values were calculated.ResultsMultivariate analysis revealed a significant impact of revascularization therapy on all perfusion measures analyzed. At baseline post-hoc testing showed significant hypoperfusion in MCA borderzones as assessed by ASL-CBF, ASL-BAT, CE-MTT and CE-CBV. All perfusion alterations normalized after revascularization. We did not observe any significant correlation of cognitive test results with perfusion parameters. There was no significant change in cognitive performance after revascularization.ConclusionWe found evidence of traceable perfusion alterations in patients with high grade carotid artery stenosis in the absence of structural brain lesions, which proved fully reversible after revascularization therapy. In this cohort of asymptomatic patients we did not observe an association of hypoperfusion with cognitive performance.

The clinical implications of adopting new criteria for the grading of internal carotid artery stenosis.

A patient's eligibility for carotid endarterectomy (CEA) is determined primarily by the degree of carotid stenosis detected on duplex ultrasound. The Australasian Society for Ultrasound in Medicine (ASUM) criteria are widely used to grade carotid stenoses in many practices throughout Australasia. We sought to investigate the potential impact on the grading of carotid artery stenosis if practitioners switched from the ASUM criteria to the United Kingdom's joint recommendation (UKJR) criteria by reviewing 100 patients with a haemodynamically significant carotid artery stenosis. We found agreement between the criteria in 100% of cases for stenoses <50%, in 80% of cases for stenoses 50-69%, in 89% of cases for stenoses ≥70% and in 100% of cases for stenoses ≥80%. While there was variation in grading of stenoses in 16% of cases, reclassification resulted in no change in the number of patients eligible for CEA. The UKJR guideline enabled more precise categorisation of haemodynamically significant stenosis into deciles. Because the UKJR guideline is more comprehensive, we believe that adopting this guideline would enable the ultrasound practitioner to grade carotid stenoses more precisely, better understand the nuances of carotid duplex imaging and more successfully navigate and interpret complex carotid examinations, without impacting the number of patients eligible for CEA.

Abstract TMP33: High Intensity Signal in the Plaque on 3DTOF MRA is Associated With Ischemic Stroke in the Patients With Low Grade Carotid Artery Stenosis

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&lt;0.001]. In multivariate logistic regression analysis, HIS (Odds ratio: 77.7, 95%CI: 6.4 - 944.0, p&lt;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.

Dual-Energy Computed Tomography Angiography of the Head and Neck With Single-Source Computed Tomography

Dual-energy computed tomographic angiography (DE-CTA) has been demonstrated to improve the visualization of the head and neck vessels. The aim of this study was to test the potential of split-filter single-source dual-energy CT to automatically remove bone from the final CTA data set. Dual-energy CTA was performed in 50 consecutive patients to evaluate the supra-aortic arteries, either to grade carotid artery stenosis or to rule out traumatic dissections. Dual-energy CTA was performed on a 128-slice single-source CT system equipped with a special filter array to separate the 120-kV spectrum into a high- and a low-energy spectrum for DE-based automated bone removal. Image quality of fully automated bone suppression and subsequent manual optimization was evaluated by 2 radiologists on maximum intensity projections using a 4-grade scoring system. The effect of image reconstruction with an iterative metal artifact reduction algorithm on DE postprocessing was tested using a 3-grade scoring system, and the time demand for each postprocessing step was measured. Two patients were excluded due to insufficient arterial contrast enhancement; in the remaining 48 patients, automated bone removal could be performed successfully. The addition of iterative metal artifact reduction algorithm improved image quality in 58.3% of the cases. After manual optimization, DE-CTA image quality was rated excellent in 7, good in 29, and moderate in 10 patients. Interobserver agreement was high (κ = 0.85). Stenosis grading was not influenced using DE-CTA with bone removal as compared with the original CTA. The time demand for DE image reconstruction was significantly higher than for single-energy reconstruction (42.1 vs 20.9 seconds). Our results suggest that bone removal in DE-CTA of the head and neck vessels with a single-source CT is feasible and can be performed within acceptable time and moderate user interaction.

Dissociation among hemodynamic measures in asymptomatic high grade carotid artery stenosis

BackgroundCerebral blood flow (CBF) regulation is a critical element in cerebrovascular pathophysiology, particularly in large vessel disease, but the best method to use for hemodynamic assessment is not clear. We examined 4 different blood-flow related measures in patients with unilateral high-grade carotid artery disease, assessing asymmetry between the occluded vs non-occluded side, and the correlations among the measures. MethodsThirty-three patients (age 50–93, 19 M) with unilateral 80–100% ICA occlusion but no stroke underwent: 1) mean flow velocity (MFV) in both middle cerebral arteries by transcranial Doppler (TCD), 2) quantitative resting CBF using pseudo-continuous arterial spin labeling (pCASL) MRI, 3) vasomotor reactivity (VMR) in response to 5% CO2 inhalation, and 4) dynamic cerebral autoregulation (DCA) assessing the counter-regulation of blood flow to spontaneous changes in blood pressure using TCD monitoring and finger photoplethysmography. Paired t-tests and Pearson correlations assessed side-to-side differences within each measure, and correlations between measures. ResultsCBF (p=0.001), MFV (p<0.001), VMR (p=0.008), and DCA (p=0.047) all showed significantly lower values on the occluded side. The 4 measures were independent of each other on correlation analysis, even when controlling for age and anterior circle of Willis collateral (all partial correlations <0.233 and p-values >0.468). ConclusionsThese 4 measures showed high sensitivity to the occluded carotid artery, but their dissociation suggests that any given measure only partially characterizes the hemodynamic state. Additional research is needed to explore the multifaceted biology of cerebral blood flow regulation.

Transatlantic Consensus of Vascular Surgery Consent

was 80e89% and the median stenosis on MRA was high grade. Peri-operative stroke rate was 1.2%. Conclusion: Carotid endarterectomy for symptomatic high grade carotid artery stenosis is carried out in our institution with acceptable peri-operative stroke rates and time interval to surgery. The centralisation of acute surgical services and availability of an emergency theatre, timely access to imaging and the availability of a stroke nurse coordinator may have facilitated faster access to surgery. Carotid disease is best managed with a multidisciplinary approach.

The implications of different criteria for grading carotid artery stenosis by duplex ultrasound.

Duplex ultrasound is the first-line mode of investigation for carotid stenosis, whose severity could be graded according to NASCET or St. Mary's ratio criteria. The aim of this study was to compare these two methods and review the literature. All patients who had carotid duplex ultrasound in a 1-month period were included. The reports and images were retrospectively reviewed, and the grade of carotid artery stenosis was then recalculated using the St. Mary's Ratio. A total of 245 (160 men) patients with a mean age 70.4 years (±11.5) were assessed, and 469 extracranial carotid systems were analyzed. Pearson's Coefficient revealed strong correlation (r = 0.79, p = 0.05) between the two methods. In 114 (24.3%) internal carotid arteries, results were different. Of these, 26 (22.8%) would have gone for surgery had they been assessed using the St. Mary's Ratio and not the NASCET grading criteria. Conversely, two internal carotid arteries (1.75%) went for surgery using the NASCET grading criteria that would not have had to should the St. Mary's Ratio been used. Although there is a strong level of correlation between the two criteria, choosing one or the other would have a significant impact on the patient' selection for surgery.

Treatment of hypertension in patients with coronary artery disease: A scientific statement from the American Heart Association, American College of Cardiology, and American Society of Hypertension

Neutrophil gelatinase associated lipocalin (NGAL) and matrix metalloproteinase (MMP)-9/NGAL complex were investigated in asymptomatic patients with carotid artery stenosis including gender specific differences aiming at vulnerable plaques prone to embolisation.Serum NGAL and MMP-9/NGAL levels were analysed in 83 patients with asymptomatic carotid artery stenosis. Pre-operative ultrasound and post-endarterectomy histology of carotid atherosclerotic lesions were evaluated.Patients with vulnerable plaques, as determined by ultrasound (plaques with decreased echogenicity) and histological analysis (type VI according to the classification of the American Heart Association), displayed the highest levels of NGAL and MMP-9/NGAL complex (p = .0003 and p = .0078, respectively). Grade VI plaques were primarily detected in patients with “soft” plaques (12 type VI plaques in 25 patients), but also in patients with mixed (four of 19) and calcified (three of 39) plaques according to ultrasound. Higher grade carotid artery stenosis (≥90%) was not associated with elevated NGAL levels. The receiver operating characteristic curve analysis detecting grade VI lesions yields an area under the curve (AUC) = 0.85, with respect to soft plaque on ultrasound the AUC = 0.86. There were no gender specific differences in levels of NGAL 80.9 (37.7) ng/mL in women vs. 76.7 (36.3) ng/mL in men, p = .607) nor of MMP-9/NGAL 33.0 (18.2–55.5) ng/mL in women vs. 36.7 (20.2–54.0) ng/mL in men, p = .969. Likewise, there were no gender associated differences in vulnerable plaque characteristics: either for grade VI plaques (17.9% vs. 27.3%, p = .582) or for the presence of soft plaques as evaluated by ultrasound (35.9% vs. 25%, p = .503).Circulating NGAL and MMP-9/NGAL are significantly increased in asymptomatic patients with vulnerable carotid atherosclerotic plaques independent of gender. Accordingly, serum NGAL may be proposed as a valuable biomarker for the detection of unstable carotid plaques in asymptomatic patients, who can then be selected for early carotid endarterectomy or stenting.

Ocular blood flow and carotid artery malfunction

to evaluate ocular hemodynamics and informativity of estimated individual normal range of intraocular pressure (IOP). A total of 12 patients (22 eyes) with carotid artery malfunction were examined. Ocular blood flow (OBF) and IOP were measured with Ocular Blood Flow Analyzer. Actual OBF was then compared with what is considered normal for a given axial length (AL). Individual normal range of IOP was calculated according to an original formula (described in previous publications). Doppler imaging of ocular vessels enabled blood flow velocity measurement. Morphological parameters and functional status of the retina and optic nerve were judged on automated perimetry (Octopus 900) and optical coherence tomography (Cirrus HD-OCT) findings. Statistical analyses were performed using Statistica 10 software. Generally, OBF showed no correlation with the grade of carotid artery stenosis (p < 0.05), however, was significantly reduced as compared to its AL-dependent norm in patients with greater than 85% narrowing of the internal carotid artery, which can cause misestimating of their individual normal range of IOP. A negative relationship was established between the blood flow velocity in short posterior ciliary arteries and the grade of internal carotid artery stenosis (p < 0.005). Ocular blood flow deficit relative to the AL-dependent norm correlated with ophthalmic artery resistance index. OBF-based estimation of individual normal range of IOP is inexpedient in patients with greater than 80% carotid artery stenosis due to its possible influence on ocular hemodynamics. In most cases of less than 80% carotid artery stenosis OBF is adequate or slightly reduced as compared to its AL-dependent norm and thus, has no significant impact on estimated individual normal range of IOP.

Grading of Carotid Artery Stenosis in the Presence of Extensive Calcifications: Dual-Energy CT Angiography in Comparison with Contrast-Enhanced MR Angiography

We investigated the agreement of dual-energy computed tomography angiography (DE-CTA) and contrast-enhanced magnetic resonance angiography (CE-MRA)in the quantitative measurement of stenoses of the internal carotid artery in comparison with digital subtraction angiography (DSA). A total of 21 patients with stenoses of the external carotid artery were investigated with a DE-CTA and CE-MRA before undergoing carotid angioplasty. The grade of the stenoses was assessed in axial multiplanar reformations (MPR) before and multi-intensity projections (MIP) after plaque subtraction (PS) and compared with results from CE-MRA and DSA according to the North American Symptomatic Carotid Endarterectomy Trial. Average grades of stenoses were 80.7 ± 16.1 % (DSA), 81.4 ± 15.3 % (MRA), 80.0 ± 16.7 % (DE-CTA-MPR), and 85.2 ± 14.7 % (DE-CTA-PS-MIP). Of 21 stenoses, 6 were filiform (stenosis grade, 99 %) in the DSA examination. Five of these cases were identified as pseudo-occlusions in MRA, while four were considered as occlusions in DE-CTA-PS-MIP. Another four cases were identified as pseudo-occlusion in DE-CTA-PS-MIP, which were identified as 90 % stenosis in the DSA examination. In comparison with the gold standard DSA, DE-CTA-MPR had a slightly better agreement in measuring the degree of stenosis of the internal carotid arteries than CE-MRA. In DE-CTA-PS-MIP images, a systematic overestimation has to be taken into account due to partial extinction of the lumen by the PS algorithm. Nevertheless, DE-CTA should be preferred in imaging patients with carotid artery stenosis in the presence of extensive calcifications.

The role of C-reactive protein genetic variability in the onset of carotid artery disease and renal function impairment in patients with diabetes mellitus type 2

The role of diabetes mellitus (DM) in cardiovascular disease is well established and currently is considered as an equivalent of coronary artery disease. Studies have also reported that DM is associated with the prevalence of occlusive carotid artery disease (AD) [ [1] Kuebler T.W. Bendick P.J. Fineberg S.E. et al. Diabetes mellitus and cerebrovascular disease: prevalence of carotid artery occlusive disease and associated risk factors in 482 adult diabetic patients. Diabetes Care. 1983; 6: 274-278 Crossref PubMed Scopus (21) Google Scholar ] as well as the grade carotid artery stenosis [ [2] Göksan B. Erkol G. Bozluolcay M. Ince B. Diabetes as a determinant of high-grade carotid artery stenosis: evaluation of 1,058 cases by Doppler sonography. J Stroke Cerebrovasc Dis. 2001; 10: 252-256 Abstract Full Text Full Text PDF PubMed Scopus (19) Google Scholar ]. In addition, DM is related to impaired renal function via several mechanisms [ [3] Vallon V. Thomson S.C. Renal function in diabetic disease models: the tubular system in the pathophysiology of the diabetic kidney. Annu Rev Physiol. 2012; 74: 351-375 Crossref PubMed Scopus (237) Google Scholar ]. During the last years novel data have arisen for the role of genetics in the initiation and progression of carotid AD [ 4 Pessi T. Eklund C. Huhtala H. et al. CRP and FCGR2A genes have an epistatic effect on carotid artery intima-media thickness: the Cardiovascular Risk in Young Finns Study. Int J Immunogenet. 2009; 36: 39-45 Crossref PubMed Scopus (6) Google Scholar , 5 Jylhävä J. Eklund C. Pessi T. et al. Genetics of C-reactive protein and complement factor H have an epistatic effect on carotid artery compliance: the Cardiovascular Risk in Young Finns Study. Clin Exp Immunol. 2009; 155: 53-58 Crossref PubMed Scopus (16) Google Scholar , 6 Bleil M.E. Ferrell R.E. Sutton-Tyrrell K. Muldoon M.F. Manuck S.B. Apolipoprotein E polymorphism and preclinical carotid artery disease in untreated hypertensive men. Eur J Cardiovasc Prev Rehabil. 2006; 13: 98-100 Crossref PubMed Scopus (4) Google Scholar , 7 Losito A. Selvi A. Jeffery S. Afzal A.R. Parente B. Cao P.G. Angiotensin-converting enzyme gene I/D polymorphism and carotid artery disease in renovascular hypertension. Am J Hypertens. 2000; 13: 128-133 Crossref PubMed Scopus (16) Google Scholar , 8 Diamantopoulos E.J. Andreadis E. Kakou M. et al. Atherosclerosis of carotid arteries and the ace insertion/deletion polymorphism in subjects with diabetes mellitus type 2. Int Angiol. 2002; 21: 63-69 PubMed Google Scholar ] as well as for impaired renal function [ 9 Hung A.M. Ikizler T.A. Griffin M.R. et al. CRP polymorphisms and chronic kidney disease in the third national health and nutrition examination survey. BMC Med Genet. 2011; 12: 65 Crossref PubMed Scopus (11) Google Scholar , 10 Cooper Worobey C. Fisher N.D. Cox D. Forman J.P. Curhan G.C. Genetic polymorphisms and the risk of accelerated renal function decline in women. PLoS One. 2009; 4: e4787 Crossref PubMed Scopus (12) Google Scholar ]. However, scarce data exist regarding genetic polymorphisms in patients with diabetes mellitus and their role in carotid artery disease and renal function. Thus, in the present study we examined the potential role of a single nucleotide polymorphism (SNP) on C-reactive protein (CRP) gene in the onset of carotid AD and impaired renal function in patients with diabetes mellitus type 2.

Abstract TP168: Angiography-Like Grading of Carotid Artery Stenosis with B-Flow Ultrasound: 3D-Ultrasound Supported Comparison with Computer Tomography Angiography Results in a High Accuracy

Background: Evaluation of various imaging modalities for grading internal carotid artery (ICA) stenosis can be performed by comparison of minimal lumen diameters (MLD) as well as percent ICA-stenosis calculated with a healthy distal reference segment (NASCET method). The two dimensional B-Flow (BF) ultrasound (US) imaging method displays stenoses in a similar fashion as reference methods like multi-slice CT-angiography (MS CTA) and in part like catheter angiography. Aim: to evaluate the accuracy of BF-US carotid stenosis grading at NASCET locations adjusted with 3D-color-Doppler ultrasound by comparison with MSCTA. Methods: Patients were screened by doppler US velocity criteria after informed consent. 3D-US was made for distance taking and search for anatomical markers. CTA were compared with BF-US in 91 ICA stenoses of 69 patients at identical projections of longitudinal sections. 58 low to high grade ICA stenoses were imaged by selective angiography and compared with CTA. Diameters of stenosed ICA were rendered coaxial on CTA. Angiography was made with AXIOM (Siemens, Germany), MSCTA with SOMATOM (Siemens, Germany); Ultrasound Logic 9 with 8 Mhz linear scanner for BF-US and a 10 Mhz 3D-US probe, GE, USA. All readings were by two independent observers for each technique. Quantitative angiography was done with MEDIS software (Netherlands), Bland-Altman analysis and statistics with SPSS (USA). Identical planes were finally confirmed by overlay technique of BF with 3D-US and CTA in addtition to the use of anatomical markers. Results: Degree of stenosis was slightly understimated by CTA compared with angiography with mean differences (±SD) of -0.4% (±6.1%) for longitudinal sections. In this cohort, discrimination of binary 50% NASCET stenosis with BF-US had a 90% sensitivity, 94% specifity and an accuracy of 91%; discrimination of binary 70% NASCET stenosis with BF-US had a sensitivity of 88%, specifity of 93% and an accuracy of 92%. Conclusion: diagnostic performance of CTA proved to be excellent compared with angiography and 3D-US adjusted BF-US measurements were highly accurate, when using corresponding projections. BF-US may be a valuable additional tool for screening and confirmation of CAS for therapeutic stratification.

Poor agreement in carotid artery stenosis detection by ultrasound between external offices and a vascular center

Carotid duplex ultrasonography is the prime investigation used to grade carotid artery stenosis in clinical routine. We compared the carotid ultrasound (US) scans performed externally with our results. This retrospective study included 288 patients who had been referred to our outpatient department and initially presented with an external carotid duplex scan report indicating carotid atherosclerosis. The external scans were analyzed and compared with our scans in respect of the accuracy of identification and quantification of stenosis, the criteria used to grade stenosis and the duplex criteria used. Weighted Kappa coefficients (K) were computed to quantify the agreement between internal and external findings. The majority of the external reports had been performed by radiologists [70.8 % (n = 204)], followed by specialists of internal medicine [19.4 (n = 56)] and by neurologists [9.8 % (n = 28)]. Only slight agreement was registered between the external reports and those performed at our institution with regard to the identification of stenosis (K = 0.2 for the left and K = 0.12 for the right side). Greater agreement was observed in respect of the level of stenosis (K = 0.42 for the right and K = 0.54 for the left side). Overestimation of the level of stenosis was registered for 45 % in the left internal carotid artery (ICA) and 36 % in the right ICA; the overestimation was most pronounced for occlusions and high-grade stenoses, which is a source of great concern for decision-making. The present data indicate only a slight agreement between carotid duplex US imaging performed at medical offices and our results.

Cerebral Hypoperfusion During Carotid Artery Stenosis can Lead to Cognitive Deficits that may be Independent of White Matter Lesion Load

Studies investigating cognitive impairment in stroke-free patients with carotid artery stenosis have led to inconsistent results. Furthermore, the pathophysiological mechanism leading to cognitive impairment remains unclear. Cerebral hypoperfusion and arterio-arterial microembolization are discussed. The aims of our study were (1) to delineate patterns of cognitive impairment in stroke-free patients with carotid artery stenosis and (2) to investigate if cognitive impairment is independent of white matter lesion load in brain MRI. We identified 212 (93 women, mean age 70.2) stroke free, non-demented patients, who were referred for carotid artery stenting or because of subjective cognitive impairment. All patients completed a neurocognitive test battery measuring verbal fluency, constructional praxis, figural memory, verbal short-term- and long-term-memory, verbal recognition memory, semantic processing, speed of cognitive processing and divided attention. Grade of maximum carotid artery stenosis was categorized into three groups (mild, moderate, or severe). White matter lesion load was graded using a visual rating scale. Cognitive test scores of groups with different grades of carotid artery stenosis were compared. Univariate regression analysis was used to measure the predictive value of carotid artery stenosis. Multivariate logistic regression analysis was performed when integrating carotid artery stenosis and white matter lesion load. Carotid artery stenosis negatively correlated with measures of verbal fluency, constructional praxis, verbal short-term-memory, semantic processing, speed of cognitive processing, and divided attention. After adjustment for white matter lesions, carotid artery stenosis did not independently predict divided attention. Significance persisted in all other cognitive domains. In our selected group of patients, a higher grade of carotid artery stenosis is associated with cognitive decline. This process is independent of white matter lesion load. Possible pathophysiological implications are discussed.

Accuracy of Digital Subtraction Angiography, Computed Tomography Angiography, and Magnetic Resonance Angiography in Grading of Carotid Artery Stenosis in Comparison With Actual Measurement in an In Vitro Model

The aim of this study was to investigate the accuracy of digital subtraction angiography (DSA), computed tomography angiography (CTA), and magnetic resonance angiography (MRA) in grading of carotid stenosis compared with actual measurement in an in vitro model. Various grades of stenosis were created by adhering different amounts of silicone rubber sealant onto the inner wall of clear, radiolucent tubes. After DSA, CTA, and MRA, the tubes were transected with 1-mm interval through the plaques. The cross-sectional areas were digitally photographed, and the percentage of area reduction of every single slide was measured with ImageJ planimetric software. The maximum actual area reduction (AAR) stenosis of each tube was recorded. The differences among DSA, CTA, MRA, and AAR were compared statistically using paired Student t test. Overall, CTA and MRA significantly underestimated the degrees of stenosis compared with AAR (P = 0.001 and P = 0.0009, respectively), and no significant difference was found between DSA and AAR (P = 0.40). In the subgroup with stenosis of <70%, there was no significant difference between DSA, CTA, and MRA versus AAR (P = 0.18, P = 0.16, and P = 0.08, respectively). In the subgroup with severe stenosis of >70%, CTA and MRA significantly underestimated the stenosis versus AAR (P = 0.004, and P = 0.007 respectively), and DSA significantly overestimated the stenosis (P = 0.0007). This in vitro model study demonstrated that CTA and MRA underestimate the lesions in severe stenosis of >70%. DSA tends to overestimate the disease. The accuracy of DSA is affected by plaque morphology, such as mountain-shaped lesions.

Concordance rates of Doppler ultrasound and CT angiography in the grading of carotid artery stenosis: a systematic literature review

Physicians have been increasingly relying on noninvasive imaging methods to grade carotid stenosis. The accuracy of Doppler ultrasound (DUS) and CT angiography (CTA) versus intra-arterial angiography (IA) has been assessed in many studies and at least two meta-analyses. Here, we performed a systematic review of studies that compared DUS to CTA. In a PubMed review of the literature from 2000 to 2009, we found 12 studies that compared DUS and CTA-based grading of carotid stenosis. Only 4 of them included at least 20 patients and provided data to classify the diseased arteries into the following categories: mild, moderate or severe NASCET stenosis or occlusion. We extracted 431 arteries from 244 patients (range per study: 48-164). It was not possible to distinguish symptomatic from asymptomatic stenoses. Nearly half arteries had severe stenosis (46% based on DUS and 43% based on CTA). The weighted kappa was 0.85 (95% CI 0.76-0.94), and the accuracy was 0.78. When the arteries were classified into medical and potentially surgical groups, the kappa was 0.76 (95% CI 0.70-0.83), and the accuracy was 0.89. Overall, 17% of the stenoses classified as medical based on DUS were reclassified as surgical based on CTA and 14% of the stenoses classified as medical based on CTA were reclassified as surgical based on DUS. The sparse available data comparing DUS and CTA suggest that the grading of a carotid stenosis as medical or potentially surgical remains uncertain in a relatively high proportion of patients.

Grading of Carotid Artery Stenosis by Novel Duplex Ultrasound Criteria: Results of the SUPERCAR Study

s S53 important information of a patient’s cardiovascular risk. Our aim was to form risk groups only by using measured US echogenicity values. Material & Methods: Within this study the ultrasound images are acquired with a Logiq 9 system (GE Healthcare) that has a special echo-level acoustic densitometry software implemented. Echo Level measures the average intensity of pixels within an areawithout any influence of observer subjective system settings, like time gain compensation (TGC), gain or dynamic range. Results: Using this method to evaluate the acquired images it seems to be possible to find an inter-observer and system independent parameter to specify the different status of plaque representations. Conclusion:Using this method to evaluate the acquired images it seems to be possible to find an inter-observer and system independent parameter to specify the different status of plaque representations.

PS88. Accuracy of CT Angiography, MR Angiography, and Digital Subtraction Angiography in Grading of Carotid Artery Stenosis: In Comparison with Actual Measurements in an In Vitro Model

PS88. Accuracy of CT Angiography, MR Angiography, and Digital Subtraction Angiography in Grading of Carotid Artery Stenosis: In Comparison with Actual Measurements in an In Vitro Model