Moderate Internal Carotid Artery Stenosis Research Articles

Internal Carotid Artery Stenosis and Ipsilateral Subretinal Drusenoid Deposits.

Subretinal drusenoid deposits (SDDs) in age-related macular degeneration (AMD) are strongly associated with vasculopathies such as myocardial infarction and ischemic stroke. This study evaluates ischemic stroke subjects for SDDs to determine whether ocular hypoperfusion from internal carotid artery (ICA) stenosis is associated with ipsilateral SDDs. A cross-sectional study at Mount Sinai Hospital recruited 39 subjects with ischemic stroke (aged 52-90; 18 women, 21 men); 28 completed all study procedures. Computed tomography (CT) of the head and neck evaluated 54/56 ICAs for stenosis criteria: none (n = 33), mild (n = 12), moderate (n = 3), severe (n = 3), and complete (n = 3). Spectral-domain optical coherence tomography (SD-OCT) scans were read to consensus by two masked graders for soft drusen, SDDs and choroidal thickness (CTh; choroidal thinning = CTh < 250µm). Univariate testing was done with Fisher's exact test. Multivariate logistic regression models tested age, gender, and ICA stenosis as covariates. Moderate or more ICA stenosis (≥50%-69%) was significantly associated with ipsilateral choroidal thinning (P = 0.021) and ipsilateral SDDs (P = 0.005); the latter were present distal to six of nine stenosed ICAs versus five of 33 normal ICAs. Mild ICA stenosis (≥1%-49%) was not significantly associated with ipsilateral SDDs. Multivariate regression found that older age (P = 0.015) and moderate or more ICA stenosis (P = 0.011) remained significant independent risks for ipsilateral SDDs. At least moderate ICA stenosis (≥50%-69%) is strongly associated with ipsilateral SDDs and choroidal thinning, supporting downstream ophthalmic artery and choroidal hypoperfusion from ICA stenosis as the mechanism for SDD formation. SDDs may thus serve as sensitive biomarkers for ischemic stroke and other vascular diseases.

Retinal microvasculature and cerebral hemodynamics in patients with internal carotid artery stenosis

PurposeTo investigate the relationship between retinal microvasculature and cerebral hemodynamics in patients with internal carotid artery (ICA) stenosis.MethodsPatients with unilateral moderate or severe ICA stenosis(≥50%) from West China hospital, Sichuan university were consecutively and prospectively recruited enrolled in the current study. En face angiograms of the superficial vascular complex (SVC), deep vascular complex (DVC), superficial vascular plexus (SVP), intermediate capillary plexus (ICP), and deep capillary plexus (DCP) were generated by automatic segmentation using swept-source optical coherence tomography angiography (SS-OCTA) to assess the retinal microvascular perfusion. The cerebral blood flow perfusion on bilateral middle cerebral artery territories measured at the basal ganglia level was assessed by brain computed tomography perfusion (CTP). CTP data were postprocessed to generate maps of different perfusion parameters including cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), mean transit time (MTT) and permeability surface(PS). Relative perfusion parameters (rPS, rCBF, etc.) were calculated as the ratio of the value on the contralateral side to that on the ipsilateral side.ResultsIn the final analysis, 31 patients were included, of whom 11 patients had a moderate ICA stenosis (50–69%) and 20 with a severe ICA stenosis(≥70%). A total of 55 eyes were analyzed in the study, 27 eyes from the ipsilateral side (ie, side with stenosis) and 28 eyes from the contralateral side. In the patients with ICA stenosis, there was a strong correlation between the retinal microvascular perfusion of SVC with rCBV(B = 0.45, p = 0.03), rCBF(B = 0.26, p = 0.02) and rPS(B = 0.45, p < 0.001) after adjustment for age, sex and vascular risk factors. Similar correlations were also found between microvasculature in SVP and cerebral perfusion changes. There were no any significant associations of microvascular perfusion in both DVC and DCP with CTP parameters(all p > 0.05).ConclusionsRetinal perfusion changes in superficial vascular layer (SVC and SVP) were correlated with brain hemodynamic compromise in patients with unilateral moderate or severe ICA stenosis(≥50%). Given the limited size of our study, future studies with larger sample size are needed to confirm our findings.

Natural History of Asymptomatic Moderate Carotid Artery Stenosis in a Large Community-Based Cohort.

Moderate carotid artery stenosis is a poorly defined risk factor for ischemic stroke. As such, practice recommendations are lacking. In this study, we describe the long-term risk of stroke in patients with moderate asymptomatic stenosis in an integrated health care system. All adult patients with asymptomatic moderate (50%-69%) internal carotid artery stenosis between 2008 and 2012 were identified, with follow-up through 2017. The primary outcome was acute ischemic stroke attributed to the ipsilateral carotid artery. Stroke rates were calculated using competing risk analysis. Secondary outcomes included disease progression, ipsilateral intervention, and long-term survival. Overall, 11 614 arteries with moderate stenosis in 9803 patients were identified. Mean age was 74.2±9.9 years with 51.4% women. Mean follow-up was 5.1±2.9 years. There were 180 ipsilateral ischemic strokes (1.6%) identified (crude annual risk, 0.31% [95% CI, 0.21%-0.41%]), of which thirty-one (17.2%) underwent subsequent intervention. Controlling for death and intervention as competing risks, the cumulative incidence of stroke was 1.2% (95% CI, 1.0%-1.4%) at 5 years and 2.0% (95% CI, 1.7%-2.4%) at 10 years. Of identified strokes, 50 (27.8%) arteries had progressed to severe stenosis or occlusion. During follow-up, there were 17 029 carotid studies performed in 5951 patients, revealing stenosis progression in 1674 (14.4%) arteries, including 1614 (13.9%) progressing to severe stenosis and 60 (0.5%) to occlusion. The mean time to stenosis progression was 2.6±2.1 years. Carotid intervention occurred in 708 arteries (6.1%). Of these, 66.1% (468/708) had progressed to severe stenosis. The overall mortality rate was 44.5%, with 10.5% of patients lost to follow-up. In this community-based sample of patients with asymptomatic moderate internal carotid artery stenosis followed for an average of 5 years, the cumulative incidence of stroke is low out to 10 years. Future research is needed to optimize management strategies for this population.

Changes of retinal structure and function in patients with internal carotid artery stenosis

BackgroundTo investigate the structural and functional changes of the retina in patients with different degrees of internal carotid artery (ICA) stenosis.MethodsThis cross-sectional study included patients with varying degrees ICA stenosis. Clinical characteristics of 41 patients were collected after being divided into four groups according to the ICA stenosis indicated by computed tomographic angiography (Group 0: without ICA stenosis, Group 1: ipsilateral slight ICA stenosis, Group 2: ipsilateral moderate ICA stenosis, Group 3: ipsilateral severe ICA stenosis). Retinal vessel caliber (RVC) was measured quantitatively with the Integrative Vessel Analysis software. The retinal sensitivity was examined with the MP-3 microperimeter. The relationships among central retinal artery equivalent (CRAE), central retinal vein equivalent, arteriole to venule ratio (AVR), mean retinal sensitivity (MS) and ICA stenosis degree were analysed.ResultsThe CRAE in Group 3 were significantly smaller compared with Group 0, Group 1 and Group 2 (P < 0.001, P < 0.001, P = 0.002). Significant decrease was found between Group 3 with other groups in MS at fovea (P < 0.001, P < 0.001, P = 0.002). Moreover, there was a positive correlation found between MS and CRAE (Beta = 0.60, P < 0.001 at fovea; Beta = 0.64, P < 0.001 at 2 degree; Beta = 0.60, P < 0.001 at 4 degree; Beta = 0.55, P < 0.001 at 8 degree; Beta = 0.53, P < 0.001 at 12 degree).ConclusionsThe present study revealed smaller CRAE and AVR in ipsilateral severe ICA stenosis patients. And the MS decreased in patients with severe ICA stenosis. In addition, MS had a positive correlation with CRAE.

Anatomical features of the occipital artery on CTA and differences between patients with/without stenosis and occlusion of the internal carotid artery.

The understanding of the basic anatomy of the occipital artery (OA) is crucial, and computed tomography angiography is an effective tool for this purpose. In the present study, a comparison between healthy subjects and patients with internal carotid artery (ICA) stenosis and occlusion was made. The following parameters were measured: Age, sex, diameters and lengths of the OA in different locations, distance from the edge of the foramen magnum to the OA and the distance from the midline to the OA at the level of the superior nuchal line. A total of 205 participants who met the inclusion criteria were selected for further investigation. In addition, 50 healthy subjects (100 sides, left and/or right) were selected as the control group. A total of 155 patients (180 sides, left and/or right) were selected as the stenosis and occlusion groups, including the mild and moderate ICA stenosis group (50 sides, left and/or right), severe ICA stenosis group (80 sides, left and/or right) and the ICA occlusion group (50 sides, left and right). General information, measured parameters and statistical analysis results are provided for these groups. No significant differences were observed in the anatomical parameters of the OA among these groups. Thus, in addition to providing anatomical data, the present study demonstrates that stenosis and the occlusion of the ICA do not significantly alter the anatomy of the OA.

Retinal vessel oxygen saturation in patients with unilateral internal carotid artery stenosis: a pilot study.

To investigate the retinal vessel oxygen saturation in patients with internal carotid artery stenosis (ICAS). This is a cross-sectional study. Sixteen patients with unilateral moderate or worse ICAS (≥50%) and no fundus diseases were included in the study. Sixteen gender- and age-matched healthy subjects were selected as controls. The mean oxygen saturation and vessel diameters of the retinal arterioles and venules were obtained using a dual-wavelength spectrophotometric retinal oximeter. In the eye of the stenotic side, the retinal vessel oxygen saturation was 100.14±10.27% in the arterioles and 56.50±10.79% in the venules, and the arteriovenous (A-V) difference was 43.63±7.71%. In the eye of the contralateral side, the oxygen saturation was 96.55±7.50% in the arterioles and 57.42±9.84% in the venules, and the A-V difference was 39.39±6.33%. In healthy subjects, the oxygen saturation was 93.22±5.98% in the arterioles and 56.57±7.05% in the venules, and the A-V difference was 36.65±7.33%. The arteriolar oxygen saturation in the stenotic side was higher than that in the contralateral side (p=0.025) and that in the healthy subjects (p=0.027), and the A-V difference in the stenotic side was significantly higher than that in the contralateral side (p=0.009) and that in the healthy subjects (p=0.013). The diameters of the arterioles in the stenotic side were smaller than those in the healthy subjects (p=0.030). Patients with ICAS had decreased retinal arteriole diameters and increased retinal vessel oxygen saturation in the arterioles and A-V differences, suggesting the presence of microcirculation disorder and hyperoxia in the retina.

Computed Tomography Perfusion Imaging Quality Affected by Different Input Arteries in Patients of Internal Carotid Artery Stenosis.

BackgroundThe aim of this study was to explore the influence of different input arteries on the parameters of computed tomography (CT) perfusion imaging for patients with different degree of stenosis of internal carotid artery (ICA).Material/MethodsForty patients were enrolled in the present study and divided into mild, moderate, severe stenosis and occlusion groups respectively with each 10 patients in each group. In reconstruction of cerebral CT perfusion (CTP) images, each raw perfusion image was reconstructed 3 times based on different reference input artery, including bilateral middle cerebral artery (MCA) and basilar arteries (BA). Region of interest (ROI) was drawn in the central territories of bilateral anterior cerebral artery, middle cerebral artery and posterior cerebral artery. And regional cerebral blood flow (rCBF) regional cerebral blood volume (rCBV), mean transit time (MTT), time to peak (TTP) and delay time (DT) were obtained from those ROI corresponding perfusion images.ResultsIn patients with mild and moderate ICA stenosis, there was no significant difference of perfusion parameters based on different input arteries (P>0.05). However, in severe ICA stenosis and occlusion CBF, MTT, and DT were significant different in affect side of the MCA group compared to the others (P<0.05).ConclusionsLarge intracranial artery can be selected as the input artery for patients with mild to moderate ICA stenosis, while for patients with severe stenosis and occlusion of ICA, the contra lateral middle cerebral artery or basilar artery would be better choice.

Abstract TP147: Relationship Between Carotid Artery Atherosclerosis and Hyoid Anatomy: Results From a Cross-sectional and Longitudinal Cohort Study

Background: Asymmetric internal carotid artery (ICA) plaque is common and are not fully explained by carotid geometry. Case reports have identified an increased risk of ICA injury and atherosclerosis with shorter hyoid wing-ICA distances. However, this relationship has not been characterized on a population level. Hypothesis: Shorter hyoid-ICA distances will be associated with greater ICA plaque and accelerated plaque formation over time. Methods: Retrospective cross-sectional and longitudinal cohort designs were used to evaluate consecutive adult patients at 3 hospitals who underwent 2 computed tomography angiography (CTA) studies of the neck ≥2 years apart (01/2000-07/2017). Patients with pre-existing neck or ICA surgery, dissection, or occlusion were excluded. Moderate ICA plaque (≥3mm), plaque characteristics, and stenosis at the level of the greater hyoid wing were compared by hyoid-ICA distance; and comparisons were made over time. Results: Sixty-six patients were included, with a median age of 64 years (IQR 53-73), 37 (56.1%) female, and 28 (42.4%) non-white. The median hyoid-ICA distance was 3.06mm (IQR 1.27-6.20mm), and when the hyoid-ICA distance was less than the median, moderate plaque was not more common (53.0% vs. 48.5%, p=0.601), and this remained non-significant after multivariable adjustment (OR 0.88, 95%CI 0.37-2.07, p=0.765) or when analyzed by hyoid-ICA distance quartile (adjusted p=0.586; Figure 1A). After a median follow-up of 1002 days (range 392-3,397 days), the odds of plaque progression (increase by ≥0.5mm) were not significantly greater when the hyoid-ICA distance was less than the median (adjusted OR 0.74, 95%CI 0.30-1.83, p=0.513), or when compared across distance quartiles (adjusted p=0.795; Figure 1B). Conclusion: In this cross-sectional and longitudinal cohort study, there was no association between hyoid wing proximity and ICA plaque thickness or stenosis.

IL-6 promoter polymorphism increased risks of recurrent stroke in the young patients with moderate internal carotid artery stenosis.

Interleukin-6 (IL-6) is a pleiotropic cytokine with both pro-inflammatory and anti-inflammatory properties. Increased serum IL-6 is associated with higher risk of cerebral vascular diseases, however, the circulating levels of IL-6 vary greatly between individuals for bioenvironmental or genetic interferes by IL-6 transcription, therefore, this study was to investigate if IL-6 promoter polymorphisms predict the recurrence of young stroke. A total of 94 patients with moderate internal carotid artery stenosis and 94 healthy subjects were selected. Color Doppler was used to screen internal carotid artery stenosis, PCR restriction enzyme fragment length polymorphism for genotypes. Stroke recurrence rates in patients with different genotypes of IL-6 promoter were evaluated by 1-year follow-up. The frequencies of 634C/G genotype of IL-6 promoter were CC 38.29%, CG 46.81%, and GG 14.90%, while CC 59.51%, CG 35.11%, GG 6.38% in the control group (P < 0.01). The frequency of G allele was significantly higher than that in the control group (38.30% vs 21.28%, P < 0.01). The relative risk was 2.2838, and 95% confidence interval was 1.0026 to 5.2026, adjusted age, sex, blood pressure, BMI, blood lipid levels and IL-6 (P < 0.05). The recurrent rate was 25.53% at 1-year follow-up; the recurrent rate among carriers with wild-type G allele (CG + GG genotype) was 32.76%, but CC 13.89% (P < 0.01). IL-6 G allele promoter increased stroke recurrent risk, therefore, it would be a predictor for recurrence of stroke in the young with moderate internal carotid artery stenosis.

Ultrasonographical Features Associated with Progression of Atherosclerosis in Patients with Moderate Internal Carotid Artery Stenosis.

Carotid artery stenosis (CAS) is a leading cause of ischemic stroke. Plaque stabilization is a major management approach. Information about the ultrasonographical and clinical features associated with the progression of moderate internal carotid artery (ICA) stenosis (50-69%) could assist with prognostication and risk factor modifications. We evaluated 287 patients with moderate ICA stenosis (50-69%) and subsequently evaluated them at follow-up points at 12, 24, and 36months. Patients were divided into three groups according to the degree of ICA stenosis: progression (70-99%, n = 48), stable (50-69%, n = 210), and regression (< 50%, n = 29). Responsible plaque thickness (RPT) across groups during follow-up was compared using a repeated measure ANOVA test. An ordinal regression was subsequently applied to identify risk factors for atherosclerosis progression. Male (P = 0.04), hypoechoic plaque (P < 0.01), smoking (P = 0.02), plaque ulceration (P = 0.05), and contralateral severe CAS or occlusions (P = 0.04) on ultrasound was more frequent in the progression group vs. other two groups. The ordinal regression revealed that only hypoechoic plaque (OR, 7.03; 95% CI, 3.34-14.81; P < 0.01) and contralateral ICA severe stenosis or occlusion (OR, 2.86; 95% CI, 1.41-5.80; P < 0.01) were independently associated with stenosis progression, while statin use was inversely associated with stenosis progression (OR, 0.26; 95% CI, 0.13-0.54; P < 0.01). Of note, symptomatic vs. asymptomatic moderate CAS at baseline was not associated with progression. For patients with moderate CAS, hypoechoic plaque, contralateral severe stenosis or occlusion on ultrasonography, and statin use are independently related to stenosis progression. Statin use may delay the progression of carotid stenosis.

Clinical Utility of Preoperative Carotid Duplex Ultrasonography Prior to Operation for Peripheral Artery Disease

Carotid duplex ultrasonography (CDUS) is one of useful screening modality for internal carotid artery stenosis (ICAS) associated with vascular disease. We aimed to clinical utility of CDUS for neurological asymptomatic patient prior to operation for peripheral artery disease (PAD). This study had institutional review board approval, and informed consent was waived. From January 2011 to December 2015, 231 consecutive patients (69.5±7.74 years, male 202 patients) who had undergone preoperative CDUS (Phlilips IU 22 , Philps Healthcare, Amsterdam, Netherland) for peripheral artery disease were included in this study and two radiologists assessed degree of ICAS by using European Carotid Surgery Trial (ECST) with consensus and severe (> 70%) ICAS or moderate ICAS (50-69%) ICAS with vulnerable plaque were defined as significant ICAS. To find out risk factors of asymptomatic significant ICAS, we analyzed demographics, co-existing medial conditions, lesion of PAD, and ankle brachial index (ABI) with multiple logistic regression model. For statistical analysis, data were tested by multiple logistic regression analysis and Chi-square test. Among 231 PAD patients, 35 patients had significant ICAS (15.1%). Multi-level lesion revealed significantly higher incidence of significant ICAS than iliac and infrainguinal lesion (22.5% vs. 9.4% vs. 8%: P = 0.016). Age (OR:1.05, 95% CI: 1.00-1.10: P = 0.035), Chronic kidney disease (CKD, OR:6.19, 95% CI: 1.47-26.06: P = 0.013) and cerebral vascular disease (CVD, OR:4.08, 95% CI: 1.09-15.30: P = 0.037) were significant risk factors of significant ICAS in multivariate analysis. Prevalence of significant ICAS according to ABI in PAD was not significant. CDUS can be a useful non-invasive preoperative screening imaging tool for evaluation of significant ICAS in PAD patients with multi-level lesion, age, CKD, and CVA.

The Influence of Low and Moderate Carotid Stenosis on Neurophysiologic Status of Patients Undergoing on-pump Coronary Artery Bypass Grafting

Background: Significant (>70%) extracranial stenosis of the internal carotid artery (ICA) is a known risk factor for brain damage in patients with coronary heart disease (CHD) undergoing coronary artery bypass grafting (CABG). There is no clear evidence of the low and moderate ICA stenoses influence on the neurophysiologic status of patients after CABG. This work was aimed at studying the influence ICA stenoses (<50%) on the dynamics of neurophysiologic status in patients undergone CABG. Methods: We examined neurophysiologic functions and electroencephalograph in CHD patients (N = 45) aged from 45 to 70 years. All patients were divided into two groups: with ICA stenosis (n = 20) and without one (n = 25). Results: It was established that the group ICA stenosis had a negative dynamics of neurophysiologic status 6 months follow-up after CABG compared with patients without stenosis. Conclusion: Our results suggest that the presence of low and moderate ICA stenosis is one of the factors affecting the neurophysiologic status of CHD patients. It has been assumed that the patients with ≤50% ICA stenoses constitute a high-risk group for cerebral complications after on-pump CABG.

Prevalence of Asymptomatic Carotid Artery Stenosis in the General Population: An Individual Participant Data Meta-Analysis

Conclusion: The prevalence of severe asymptomatic internal carotid artery (ICA) stenosis in the general population ranges from 0% to 3.1%. Summary: The authors sought to determine the prevalence of moderate and severe asymptomatic ICA stenosis using information from four population-based cohort studies. They used pooled cohort data to analyze prevalence of moderate and severe asymptomatic ICA stenosis by age and sex. This was an individual participant data meta-analysis of 23,706 participants from four population-based studies: the Malmo Diet and Cancer Study, Tromoso, Carotid Atherosclerosis Progression Study, and the Cardiovascular Health Study. Moderate asymptomatic ICA stenosis was defined as >50% to 69% stenosis. Severe stenosis was defined as >70% stenosis. Moderate asymptomatic ICA stenosis had a prevalence ranging from 0.2% (95% CI, 0.0%-0.4%) in men aged <50 years to 7.5% (95% CI, 5.2%-10.5%) in men aged ≥80 years. In women, prevalence of asymptomatic ICA stenosis ranged from 0% (95% CI, 0%-0.2%) to 5% (95% CI, 3.1%-7.5%). Severe asymptomatic ICA stenosis ranged from 0.1% to 3.1% (95% CI, 0.0%-0.3%) in men aged <50 years and from 1.7% to 5.3% in men aged >80. In women, the prevalence of severe asymptomatic ICA stenosis increases from 0% (95% CI, 0.0%-0.2%) in those aged <50 years to 0.9% (95% CI, 0.3%-2.4%) in those aged <80 years, respectively. Comment: Screening for asymptomatic ICA stenosis has not been endorsed by the US Preventative Health Services Task Force. There are no data here that will lead to a change in their opinion. Up to age 70 years, the prevalence of high-grade asymptomatic carotid stenosis is <2%. No comorbidity increases that prevalence beyond 2%. Given the relatively benign natural history of asymptomatic ICA stenosis, it seems highly unlikely from these data that screening for asymptomatic high-grade ICA stenosis can be clinically effective or cost-effective in any patient subgroup.

Fluorine-18-Fluorodeoxyglucose Positron Emission Tomography May Predict the Outcome in Patients With Asymptomatic Mild Stenosis of Internal Carotid Artery -Case Report-

A 47-year-old male presented with asymptomatic mild (45%) internal carotid artery (ICA) stenosis associated with familial hypercholesterolemia. Fluorine-18-fluorodeoxyglucose ([(18)F]FDG) positron emission tomography (PET) showed that the carotid plaque had high uptake of [(18)F]FDG on the initial scan. He was treated with antiplatelet agent, but subsequently developed retinal artery occlusion on the ipsilateral side. The patient safely underwent carotid endarterectomy (CEA). Histological examination revealed that the plaque was rich in lipids and activated macrophages. Previous large randomized clinical trials have clarified that CEA is an effective therapeutic option to reduce the risk for subsequent ischemic stroke in patients with severe (more than 70%) ICA stenosis. The case strongly suggests that [(18)F]FDG PET may be a useful modality to identify inflamed and/or vulnerable carotid plaque and may be useful to predict the risk for subsequent ischemic stroke even in patients with mild to moderate ICA stenosis (less than 70%).

In Vivo Wall Shear Stress Distribution in the Carotid Artery

Background— The purpose of this study was to analyze the in vivo distribution of absolute wall shear stress (WSS abs ) and oscillatory shear index (OSI) in the carotid bifurcation and to evaluate its dependence on bifurcation geometry, the presence of internal carotid artery (ICA) stenosis, and recanalization therapy. Methods and Results— Time-resolved 3D blood flow was acquired with flow-sensitive 4D MRI in 64 normal carotid bifurcations and 17 carotid arteries with moderate ICA stenosis (48±6%) or after surgical recanalization. Among 64 normal arteries, atherogenic wall parameters were consistently concentrated in proximal bulb regions of the common (CCA) and internal (ICA) carotid arteries. The fraction of the carotid bulb exposed to atherosclerosis-prone wall parameters (low WSS abs below and high OSI above group-defined 20% and 10% thresholds) was correlated with the individual bifurcation geometry. Multiple regressions revealed significant ( P &lt;0.01) relationships (β, 0.44 to 0.48) between the areas with atherosclerosis-prone wall parameters and the d ICA /d CCA diameter ratio. The size of regions exposed to high OSI demonstrated highly significant ( P ≤0.01) relationships with all analyzed geometry parameters (d ICA /d CCA β, 0.48; tortuosity β, ≤−0.56; bifurcation angle β, ≥0.47). Moderate ICA stenosis altered the distribution of wall parameters (45%/61% reduction of individually low WSS abs /high OSI in the proximal ICA), which were relocated to segments distal to the arterial stenosis. WSS abs /OSI topology after recanalization was similar compared with the normal wall parameter distribution. Conclusions— Flow-sensitive 4D MRI identified alterations in the segmental in vivo WSS distribution associated with atherosclerotic disease, surgical therapy, and individual bifurcation geometry and could be a valuable technique to assess the individual risk of flow-mediated atherosclerosis and carotid plaque progression.

Magnetic resonance angiography, digital subtraction angiography and Doppler ultrasonography in detection of carotid artery stenosis: a comparison with findings from histological specimens

Patients' life expectancy, clinical symptomatology and the extent of carotid stenosis are the most important factors when deciding whether to perform carotid endarterectomy (CEA) in patients with carotid stenosis. Therefore, the accuracy of measuring carotid stenosis is of utmost importance. Patients with internal carotid artery (ICA) stenosis were investigated by digital subtraction angiography (DSA), Doppler ultrasonography (DUS) and magnetic resonance angiography (MRA). Atherosclerotic plaque specimens were transversally cut into smaller segments and histologically processed. The slides were scanned and specimens showing maximal stenosis were determined; the minimal diameter and the diameter of the whole plaque were measured. DSA, DUS and MRA measurements were obtained in 103 patients. A comparison between preoperative and histological findings was performed. In addition, correlation coefficients were computed and tested. Results show a significant correlation for each of the diagnostic procedures. Mean differences in the whole cohort between preoperative measurements and the histological measurements are as follows: angiographic measurement of carotid stenosis underestimated histological measurement by 14.5% and MRA by 0.7%, but DUS overestimated by 6.6%. The results in severe stenosis (> or =70%) are as follows: angiographic measurement underestimated the histological measurements by 2.3%, but MRA overestimated by 12.1% and DUS by 11.3%. The results in moderate stenosis (50-69%): angiographic measurement underestimated the histological measurements by 12.3%, but MRA overestimated by 0.2% and DUS by 7.2%. The results in mild stenosis (30-49%): angiographic measurement underestimated the histological measurements by 24.7% and MRA by 7.6%, but DUS overestimated by 3.3%. Our study confirms that DSA underestimates moderate and mild ICA stenosis. DUS slightly overestimated moderate ICA stenosis and highly overestimated high-grade ICA stenosis. MRA proved to be accurate in detecting moderate ICA stenosis, but slightly underestimated mild stenosis and overestimated high-grade stenosis. The surgeon should be aware of these discrepancies when deciding whether to perform CEA in patients with ICA stenosis.

Extracranial infected carotid artery aneurysm

Infected aneurysms of the extracranial carotid arteries are rare. This is a case report of a 63-year-old female who developed an infected internal carotid artery aneurysm due to group B Streptococcus ten days after a dental procedure. She was successfully treated with excision of the aneurysm and common to internal carotid artery bypass with greater saphenous vein.

Dynamic cerebral autoregulation in carotid stenosis before and after carotid stenting

Impaired dynamic cerebral autoregulation (DCA) has been shown in patients with severe (> or =70%) internal carotid artery (ICA) stenosis, but DCA in moderate (50% to 69%) ICA stenosis, especially its response to carotid revascularization, has rarely been reported. Our study aimed to characterize DCA in severe and moderate ICA stenosis before and after carotid stenting. This study included 21 patients with ICA stenosis > or =50% who received carotid stenting. Data of arterial blood pressure and cerebral blood flow velocity of the middle cerebral artery, measured by transcranial Doppler, were collected for 10 minutes < or =24 hours before and after stenting. The DCA index, represented as aMx, was assessed by calculating the Pearson product-moment correlation coefficient of spontaneous arterial blood pressure and cerebral blood flow velocity fluctuations. The relationship between aMx and stenotic severity and also alternations of aMx before and after stenting were assessed. Carotid stenting was effective to improve the DCA in the stenting side but not in the contralateral nonstenting side. In considering individual ICAs, the average aMx (mean +/- SD) increased significantly from ICA stenosis <50% (0.117 +/- 0.091) to 50% to 69% (0.349 +/- 0.144), 70% to 99% (0.456 +/- 0.147), and total occlusion (0.557 +/- 0.210; P < .05, P < .01, and P < .01, compared with 50% to 69%, 70% to 99%, or total occlusion with <50% stenosis). The correlation between the degree of ICA stenosis and the aMx was also significant (r = 0.693, P < .005). The aMx improved significantly in the stented side after carotid stenting in both moderate and severe ICA stenosis, and this finding was not affected by age, sex, risk factors, or clinical symptoms. In addition to patients with severe carotid stenosis, patients with moderate carotid stenosis may also have impaired DCA that can be restored after carotid stenting.

Preoperative Doppler sonography for prevention of perioperative stroke in head and neck cancer patients undergoing neck dissection: Is it beneficial?

Journal of Clinical UltrasoundVolume 35, Issue 1 p. 38-39 CorrespondenceFree Access Preoperative Doppler sonography for prevention of perioperative stroke in head and neck cancer patients undergoing neck dissection: Is it beneficial? Mustafa A. Atik, Mustafa A. Atik 8181 Fannin Street, No. 728, Houston, TX 77054Search for more papers by this authorMehmet Ates, Mehmet Ates 8181 Fannin Street, No. 728, Houston, TX 77054Search for more papers by this authorNuri I. Akkus, Nuri I. Akkus 8181 Fannin Street, No. 728, Houston, TX 77054Search for more papers by this authorOzden Altundag, Ozden Altundag 8181 Fannin Street, No. 728, Houston, TX 77054Search for more papers by this authorKadri Altundag, Kadri Altundag 8181 Fannin Street, No. 728, Houston, TX 77054Search for more papers by this author Mustafa A. Atik, Mustafa A. Atik 8181 Fannin Street, No. 728, Houston, TX 77054Search for more papers by this authorMehmet Ates, Mehmet Ates 8181 Fannin Street, No. 728, Houston, TX 77054Search for more papers by this authorNuri I. Akkus, Nuri I. Akkus 8181 Fannin Street, No. 728, Houston, TX 77054Search for more papers by this authorOzden Altundag, Ozden Altundag 8181 Fannin Street, No. 728, Houston, TX 77054Search for more papers by this authorKadri Altundag, Kadri Altundag 8181 Fannin Street, No. 728, Houston, TX 77054Search for more papers by this author First published: 27 November 2006 https://doi.org/10.1002/jcu.20274Citations: 8AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article. REFERENCES 1 Cheng SW, Wu LL, Ting AC, et al. Irradiation-induced extracranial carotid stenosis in patients with head and neck malignancy. Am J Surg 1999; 178: 323. 2 Carmody BJ, Arora S, Avena R, et al. Accelerated carotid artery disease after high-dose head and neck radiotherapy: is there a role for routine carotid duplex surveillance? J Vasc Surg 1999; 30: 1045. 3 Lam WW, Yuen HY, Wong KS, et al. Clinically underdetected asymptomatic and symptomatic carotid stenosis as a late complication of radiotherapy in Chinese nasopharyngeal carcinoma patients. Head Neck 2001; 23: 780. 4 Calliada F, Verga L, Pozza S, et al. Selection of patients for carotid endarterectomy: the role of ultrasound. J Comput Assist Tomogr 1999; 2( Suppl 1): S75. 5 Mansour MA, Littooy FN, Watson WC, et al. Outcome of moderate carotid artery stenosis in patients who are asymptomatic. J Vasc Surg 1999; 29: 217. 6 Olin JW, Fonseca C, Childs MB, et al. The natural history of asymptomatic moderate internal carotid artery stenosis by duplex ultrasound. Vasc Med 1998; 3: 101. 7 Samant S, Robbins KT. Evolution of neck dissection for improved functional outcome. World J Surg 2003; 27: 805. 8 Nosan DK, Gomez CR, Maves MD. Perioperative stroke in patients undergoing head and neck surgery. Ann Otol Rhinol Laryngol 1993; 102: 717. 9 Thompson SK, Southern DA, McKinnon JG, et al. Incidence of perioperative stroke after neck dissection for head and neck cancer: a regional outcome analysis. Ann Surg 2004; 239: 428. Citing Literature Volume35, Issue1January 2007Pages 38-39 ReferencesRelatedInformation

Carotid sonography and transesophageal echocardiography in patients with ischemic stroke or transient ischemic attack in the territory of the carotid artery

To assess the benefit of combining carotid sonography and transesophageal echocardiography (TEE) for the evaluation of patients with stroke or transient ischemic attack (TIA) in the territory of the carotid artery. During a 2-year period in Turku University Hospital, consecutive in patients with stroke or TIA who were candidates for carotid endarterectomy and for oral anticoagulation were evaluated with carotid sonography for symptomatic moderate (50-69%) or severe (>or=70%) internal carotid artery (ICA) stenosis, and with TEE for potential cardiac sources of embolism. In 20% (40/197) of patients, a severe symptomatic ICA stenosis and/or a major risk factor for a cardiac source of embolism were found. In 56% (110/197) of patients, a moderate or severe symptomatic ICA stenosis and/or a potential cardiac source of embolism were found, whereas 11% (21/197) of patients had both a moderate or severe symptomatic ICA stenosis and a potential cardiac source of embolism. This study suggests that the presence of a moderate or severe symptomatic ICA stenosis does not exclude the presence of a potential cardiac source of embolism and vice versa. Carotid sonography and TEE complement each other and are valuable diagnostic tools that should be recommended in patients with ischemic stroke or TIA in the territory of the carotid artery when they are candidates for carotid endarterectomy and for oral anticoagulation.