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Purpose: The aim of this study was to assess vascular changes and blood flow abnormalities in the common carotid arteries of patients with head and neck cancers after external radiotherapy, using color Doppler ultrasonography. Methods: We studied 24 patients treated with external radiotherapy for various head and neck cancers. In order to study the acute effects of irradiation on common carotid blood flow and arterial diameter changes, color Doppler ultrasonography parameters such as peak systolic velocity, end diastolic velocity, mean velocity, systolic-to-diastolic velocity (S/D) ratio, pulsatility index (PI), resistive index (RI), and instantaneous diameter changes were evaluated before and after external radiotherapy. Additionally, the blood volume flow (VF) values in the peak systolic and end diastolic phases, as well as mean velocity, were evaluated throughout three cardiac cycles using B-mode ultrasonic image processing. Results: The findings showed significant changes in the S/D ratio, PI, and RI of the common carotid arteries before and after external radiotherapy (P<0.05). Moreover, a significant decrease in artery diameter and blood VF was observed after radiotherapy relative to the pretreatment values. A significant correlation was found between the blood VF values estimated using ultrasonic measurements and mathematical methods throughout three cardiac cycles. Conclusion: The hemodynamic parameters of the common carotid arteries changed during radiotherapy. These arterial changes may lead to late adverse effects of radiotherapy, such as ischemic strokes and ischemic attacks. [ABSTRACT FROM AUTHOR]

Objective In this study, we sought to investigate the feasibility of fast carotid artery MR angiography (MRA) by combining three-dimensional time-of-flight (3D TOF) with compressed sensing method (CS-3D TOF). Materials and methods A pseudo-sequential phase encoding order was developed for CS-3D TOF to generate hyper-intense vessel and suppress background tissues in under-sampled 3D k-space. Seven healthy volunteers and one patient with carotid artery stenosis were recruited for this study. Five sequential CS-3D TOF scans were implemented at 1, 2, 3, 4 and 5-fold acceleration factors for carotid artery MRA. Blood signal-to-tissue ratio (BTR) values for fully-sampled and under-sampled acquisitions were calculated and compared in seven subjects. Blood area (BA) was measured and compared between fully sampled acquisition and each under-sampled one. Results There were no significant differences between the fully-sampled dataset and each under-sampled in BTR comparisons ( P > 0.05 for all comparisons). The carotid vessel BAs measured from the images of CS-3D TOF sequences with 2, 3, 4 and 5-fold acceleration scans were all highly correlated with that of the fully-sampled acquisition. The contrast between blood vessels and background tissues of the images at 2 to 5-fold acceleration is comparable to that of fully sampled images. The images at 2 × to 5 × exhibit the comparable lumen definition to the corresponding images at 1 ×. Conclusion By combining the pseudo-sequential phase encoding order, CS reconstruction, and 3D TOF sequence, this technique provides excellent visualizations for carotid vessel and calcifications in a short scan time. It has the potential to be integrated into current multiple blood contrast imaging protocol. [ABSTRACT FROM AUTHOR]

Background and purpose: Techniques to stratify subgroups of patients with asymptomatic carotid artery disease are urgently needed to guide decisions on optimal treatment. Reliance on estimates of % luminal stenosis has not been effective, perhaps because that approach entirely disregards potentially important information on the pathological process in the wall of the artery. Methods: Since plaque lipid is a key determinant of plaque behaviour we used a newly validated, high-sensitivity T2-mapping MR technique for a systematic survey of the quantity and distribution of plaque lipid in patients undergoing endarterectomy. Lipid percentage was quantified in 50 carotid endarterectomy patients. Lipid distribution was tested, using two imaging indices (contribution of the largest lipid deposit towards total lipid (LLD %) and a newly-developed LAI ‘lipid aggregation index’). Results: The bifurcation contained maximal lipid volume. Lipid percentage was higher in symptomatic vs. asymptomatic patients with degree of stenosis (DS ≥ 50%) and in the total cohort (P = 0.013 and P = 0.005, respectively). Both LLD % and LAI was higher in symptomatic patients (P = 0.028 and P = 0.018, respectively), suggesting that for a given plaque lipid volume, coalesced deposits were more likely to be associated with symptomatic events. There was no correlation between plaque volume or lipid content and degree of luminal stenosis measured on ultrasound duplex (r = -0.09, P = 0.53 and r = -0.05, P = 0.75), respectively. However, there was a strong correlation in lipid between left and right carotid arteries (r = 0.5, P <0.0001, respectively). Conclusions: Plaque lipid content and distribution is associated with symptomatic status of the carotid plaque. Importantly, plaque lipid content was not related to the degree of luminal stenosis assessed by ultrasound. Determination of plaque lipid content may prove useful for stratification of asymptomatic patients, including selection of optimal invasive treatments. [ABSTRACT FROM AUTHOR]

Background: Image-based computational models are widely used to determine atherosclerotic plaque stress/strain conditions and investigate their association with plaque progression and rupture. However, patient-specific vessel material properties are in general lacking in those models, limiting the accuracy of their stress/strain measurements. A noninvasive approach of combining in vivo 3D multi-contrast and Cine magnetic resonance imaging (MRI) and computational modeling was introduced to quantify patient-specific carotid plaque material properties for potential plaque model improvements. Vessel material property variation in patients, along vessel segment, and between baseline and follow up were investigated. Methods: In vivo 3D multi-contrast and Cine MRI carotid plaque data were acquired from 8 patients with follow-up (18 months) with written informed consent obtained. 3D thin-layer models and an established iterative procedure were used to determine parameter values of the Mooney-Rivlin models for the 81slices from 16 plaque samples. Effective Young’s Modulus (YM) values were calculated for comparison and analysis. Results: Average Effective Young’s Modulus (YM) and circumferential shrinkage rate (C-Shrink) value of the 81 slices was 411kPa and 5.62%, respectively. Slice YM value varied from 70 kPa (softest) to 1284 kPa (stiffest), a 1734% difference. Average slice YM values by vessel varied from 109 kPa (softest) to 922 kPa (stiffest), a 746% difference. Location-wise, the maximum slice YM variation rate within a vessel was 311% (149 kPa vs. 613 kPa). The average slice YM variation rate for the 16 vessels was 134%. The average variation of YM values for all patients from baseline to follow up was 61.0%. The range of the variation of YM values was [-28.4%, 215%]. For plaque progression study, YM at follow-up showed negative correlation with plaque progression measured by wall thickness increase (WTI) (r = -0.7764, p = 0.0235). Wall thickness at baseline correlated with WTI negatively, with r = -0.5253 (p = 0.1813). Plaque burden at baseline correlated with YM change between baseline and follow-up, with r = 0.5939 (p = 0.1205). Conclusion: In vivo carotid vessel material properties have large variations from patient to patient, along the diseased segment within a patient, and with time. The use of patient-specific, location specific and time-specific material properties in plaque models could potentially improve the accuracy of model stress/strain calculations. [ABSTRACT FROM AUTHOR]

Objective Although carotid artery stenting (CAS) has been gaining popularity as an alternative to carotid endarterectomy (CEA), perioperative stroke rate following contemporary CAS remains significantly higher than stroke rate after CEA. The purpose of this study was to assess perioperative (within 30 days) therapeutic results in patients with carotid stenosis (CS) after introduction of preoperative carotid magnetic resonance imaging plaque evaluation in a single center performing both CEA and CAS. Methods Based on prospectively collected data for patients with CS who were scheduled for carotid revascularization, retrospective analysis was conducted of 295 consecutive patients with CS. An intervention was selected after consideration of periprocedural risks for both CEA and CAS. Concerning risk factors for CAS, results of magnetic resonance imaging plaque evaluation were emphasized with a view toward reducing embolic complications. Results CAS was performed in 114 patients, and CEA was performed in 181 patients. Comparing baseline characteristics of the 295 patients, age, T1 signal intensity of plaque, symptomatic CS, urgent intervention, and diabetes mellitus differed significantly between CAS and CEA groups. Among patients who underwent CAS, new hyperintense lesions on diffusion-weighted imaging were confirmed in 47 patients. New hyperintense lesions on diffusion-weighted imaging were recognized in 21.4% of patients who underwent CEA ( n = 39), significantly less frequent than in patients who underwent CAS. Conclusions The overall short-term outcome of CEA and CAS is acceptable. Preoperative carotid magnetic resonance imaging evaluation of plaque might contribute to low rates of ischemic complications in CAS. [ABSTRACT FROM AUTHOR]

Background Carotid intima-media thickness ( IMT) and plaque are recognized markers of increased risk for cerebrovascular events. Accurate visualization of the IMT and plaques is dependent upon image quality. Ultrasound contrast agents improve image quality during echocardiography-this study assessed whether contrast-enhanced ultrasound ( CEUS) improves carotid IMT visualization and plaque detection in an asymptomatic population. Methods & Results Individuals free from known cardiovascular disease, enrolled in a community study, underwent B-mode and CEUS carotid imaging. Each carotid artery was divided into 10 segments (far and near walls of the proximal, mid and distal segments of the common carotid artery, the carotid bulb, and internal carotid artery). Visualization of the IMT complex and plaque assessments was made during both B-mode and CEUS imaging for all enrolled subjects, a total of 175 individuals (mean age 65±9 years). Visualization of the IMT was significantly improved during CEUS compared with B-mode imaging, in both near and far walls of the carotid arteries (% IMT visualization during B-mode vs CEUS imaging: 61% vs 94% and 66% vs 95% for right and left carotid arteries, respectively, P<.001 for both). Additionally, a greater number of plaques were detected during CEUS imaging compared with B-mode imaging (367 plaques vs 350 plaques, P=.02). Conclusion Contrast-enhanced ultrasound improves visualization of the intima-media complex, in both near and far walls, of the common and internal carotid arteries and permits greater detection of carotid plaques. Further studies are required to determine whether there is incremental clinical and prognostic benefit related to superior plaque detection by CEUS. [ABSTRACT FROM AUTHOR]

Purpose: We propose a magnetic resonance (MR) imaging protocol for the characterization of carotid web morphology, composition, and vessel wall dynamics. The purpose of this case series was to determine the feasibility of imaging carotid webs with MR imaging. Methods: Five patients diagnosed with carotid web on CT angiography were recruited to undergo a 30-min MR imaging session. MR angiography (MRA) images of the carotid artery bifurcation were acquired. Multi-contrast fast spin echo (FSE) images were acquired axially about the level of the carotid web. Two types of cardiac phase resolved sequences (cineFSE and cine phase contrast) were acquired to visualize the elasticity of the vessel wall affected by the web. Results: Carotid webs were identified on MRA in 5/5 (100%) patients. Multi-contrast FSE revealed vessel wall thickening and cineFSE demonstrated regional changes in distensibility surrounding the webs in these patients. Conclusion: Our MR imaging protocol enables an in-depth evaluation of patients with carotid webs: morphology (by MRA), composition (by multi-contrast FSE), and wall dynamics (by cineFSE). [ABSTRACT FROM AUTHOR]

Carotid atherosclerotic disease constitutes a major modern health problem whose diagnosis primarily relies on imaging. Grading of stenosis has been long used as the main factor for risk stratification and guiding of management. Nevertheless, increasing evidence has shown that additional plaque characteristics such as plaque composition and surface morphology play an important role in the occurrence of symptoms, justifying the term 'vulnerable plaque'. Carotid plaque surface characteristics either in the form of surface irregularities or ulceration represent an important factor of vulnerability and are associated with the occurrence of neurologic symptoms. The delineation of the carotid plaque surface can be performed with virtually all imaging modalities including ultrasound, contrast-enhanced ultrasound, multi-detector computed tomography angiography, magnetic resonance angiography and the traditional reference method of angiography. These techniques have shown varying levels of diagnostic accuracy for the identification of ulcerated carotid plaques or plaque surface irregularities. As a consequence and given its high clinical significance, radiologists should be familiar with the various aspects of this entity, including its definition, classification, imaging findings on different imaging modalities and associations. The purpose of this review is to present the current literature regarding carotid plaque ulcerations and present illustrative images of ulcerated carotid plaques. Teaching Points : • Plaque surface and ulceration represent risk factors for stroke in carotid disease. • Characterisation of the plaque surface and ulcerations can be performed with every modality. • US is the first-line modality for carotid disease and identification of ulcerations. • The administration of microbubbles increases US accuracy for diagnosis of carotid ulceration. • MDCTA and MRA are valuable for diagnosing ulceration and evaluating plaque composition. [ABSTRACT FROM AUTHOR]

Photoacoustic imaging (PAI) may have the ability to reveal the composition and the anatomical structure of carotid plaques, which determines its mechanical properties and vulnerability. We used PAI and plane wave ultrasound (PUS) imaging to obtain three-dimensional (3-D) images of endarterectomy samples ex vivo and compared the results with histology to investigate the potential of PAI-based identification of intraplaque hemorrhage. Seven carotid plaque samples were obtained from patients undergoing carotid endarterectomy and imaged with a fully integrated hand-held photoacoustic (PA) probe, consisting of a pulsed diode laser (t PULSE = 130 ns, EPULSE = 1 mJ, λ = 808 nm) and a linear array transducer (f c = 7.5 MHz). The samples were rotated 360 deg with 10 deg steps, and data were spatially compounded to obtain complete 3-D images of the plaques. Areas of high absorption in the 3-D datasets were identified and compared to histological data of the plaques. Data in six out of seven endarterectomy samples revealed the presence of intraplaque hemorrhages that were not visible in the PUS images. Due to the noninvasive nature of PAI, this ex vivo study may elucidate preclinical studies toward the in vivo, noninvasive, vulnerability assessment of the atherosclerotic carotid plaque. [ABSTRACT FROM AUTHOR]

Background and purpose: Small deep brain infarcts are often caused by two different vascular pathologies: branch atheromatous disease (BAD) and lipohyalinotic degeneration (LD). In this study, we compare the clinical characteristics of BAD and LD and investigate the role of C-reactive protein (CRP), homocysteine (Hcy), and carotid artery intima-media thickness (IMT) in the prognosis of patients with BAD and LD.Methods: Of 262 adult patients with small deep infarcts, 104 were considered BAD and 158 were considered LD. Data compared included clinical information, prevalence of lacune and leukoaraiosis, Hcy, CRP, carotid artery IMT, deterioration during admission, and recurrence of ischemic stroke (IS) within 1 year.Results: Patients with LD have severe leukoaraiosis and higher prevalence of lacune and intracerebral hemorrhage compared with those with BAD. Patients with BAD have higher initial National Institutes of Health Stroke Scale scores and incidence of progressive motor deficits compared with those with LD; CRP is associated with the progression in both groups. There is no statistical difference of recurring risk of IS within 1 year between the two groups; by multivariable logistic regression analysis, carotid artery IMT was an independent risk factor for recurrence of IS in 1 year in patients with BAD.Conclusion: BAD as an independent clinical entity has different clinical and radiological characteristics compared with LD. Carotid artery IMT is an independent risk factor for recurrence of IS in patients with BAD. [ABSTRACT FROM PUBLISHER]

Purpose To demonstrate the feasibility of measuring the common carotid artery ( CCA) lumen dynamics using a black-blood cine ( BB-cine) imaging method. Methods Motion-sensitized driven-equilibrium ( MSDE) prepared spoiled gradient sequence was used for the BB-cine imaging. CCAs of eleven healthy volunteers were studied using this method. Lumen dynamics, including lumen area evolution waveforms and distension values, were measured and evaluated by comparing this method with bright-blood cine (BrB-cine) imaging. Results Compared with the BrB-cine images, flow artifacts were effectively suppressed in the BB-cine images. BrB-cine images generally show larger lumen areas than BB-cine images. The lumen area waveforms and distension measurements from BB-cine imaging showed smaller variances among different subjects than BrB-cine imaging. Conclusions The proposed BB-cine imaging technique can suppress the flow artifacts effectively and reduce the partial volume effects from the vessel wall. This might allow more accurate lumen dynamics measurements than traditional BrB-cine imaging, which may further be valuable for investigating biomechanical and functional properties of the cardiovascular system. [ABSTRACT FROM AUTHOR]

We compared intima-media thickness (IMT) and the prevalence of plaques in the common carotid artery (CCA) and common femoral artery (CFA) in apparently healthy participants. This multicenter study included 322 participants (59.9% female; age 20-78 years, mean 52.1 ± 15.3 years) who underwent Echo-color Doppler examination of the CCA and CFA bilaterally. Prevalence and composition of plaque were recorded. A significant (P < .01) difference between mean CCA-IMT and mean CFA-IMT was detected (0.70 vs 0.73 mm). Plaque prevalence was significantly higher in the CFA compared to the CCA (40.7% vs 30.4%). Atherosclerotic plaques were found in both CFA and CCA in 46% of the cases, solely in CFA in 38%, and in CCA alone in 17%. The observed difference in plaque prevalence was even greater when only fibrolipid isolated plaques were considered (CFA 39.4% vs CCA 22.1%). In a healthy general population, atherosclerotic plaques were present in the CFA but not in the CCA in over onethird of the cases. Further studies must confirm whether ultrasonography of the CFA might be introduced in the screening protocols for cardiovascular risk assessment. [ABSTRACT FROM AUTHOR]

Purpose: We investigated whether laser speckle flowgraphy (LSFG) results are comparable in both eyes and whether it is useful in the diagnosis of disparity in ocular ischemic syndrome (OIS) patients. Methods: We compared the mean blur rate (MBR) value for various fundus regions in both eyes of 41 healthy subjects and 15 internal carotid artery occlusion (ICAO) cases. We calculated the standard value of the Laterality Index (LI), which was the MBR comparison of both eyes in each of the regions, in the control subjects. We then investigated the correlation between both eyes for the LIs in the entire fundus, the degree of ICAO and visual function. Results: The disparity of the LIs in both eyes was least in the entire area of the fundus in control subjects and there was a significant correlation between both eyes of the 41 healthy individuals (P = 0.019). Significant correlations were found for the LI, visual acuity and degree of ICAO. The specificity and sensitivity of LI in the entire area was 93.8% and 100%, respectively. Conclusions: LSFG revealed normal individuals have symmetrical fundus blood flow. LSFG could detect OIS and might be a useful tool for detecting disparities in fundus blood flow. [ABSTRACT FROM AUTHOR]

Objectives: To assess the efficacy and safety profile of stent-retriever thrombectomy (SRT) in acute anterior ischemic stroke patients with tandem occlusion.Materials and Methods: Using the MEDLINE database, we conducted a systematic review and meta-analysis of all studies that included patients with acute ischemic stroke attributable to tandem occlusion who received treatment with SRT between November 2010 and May 2015.Results: The literature search identified 11 previous studies involving a total of 237 subjects out of whom 193 (81.4 %) were treated with acute stent placement for the extracranial internal carotid artery occlusion. Mean initial NIHSS score was 17, and median time from onset to recanalization was 283.5 min. Mean intravenous thrombolysis rate was 63.8 %. In the meta-analysis, the recanalization rate reached 81 % (95 % CI, 73-89). Meta-analysis of clinical outcomes showed a pooled estimate of 44 % (95 % CI, 33-55; 10 studies) for favourable outcome, 13 % (95 % CI, 8-20; 10 studies) for mortality, and 7 % (95 % CI, 2-13; eight studies) for symptomatic intracranial haemorrhage.Conclusion: SRT with emergency carotid stenting is associated with acceptable safety and efficacy in acute anterior stroke patients with tandem occlusion compared to natural history. However, the best modality to treat proximal stenosis is based on an individual case basis.Key Points: • Stent retriever thrombectomy of tandem occlusion is efficient and safe. • Emergent carotid stenting during thrombectomy increase symptomatic intracranial haemorrhage without impact mortality. • Thrombectomy of tandem anterior circulation occlusion may be the first therapeutic option. [ABSTRACT FROM AUTHOR]

Background: The multi-contrast assessment of the carotid artery wall has become an important diagnostic tool for the characterization of atherosclerotic plaque and vessel wall thickening. For providing the required T1-, T2-, and proton density weighted contrast, multi-slice turbo spin echo (TSE) techniques are normally applied. The straightforward extension of the TSE techniques to volumetric imaging of large sections of the carotid arteries is limited by the resulting long acquisition times. Where the acquisition of a T1-weighted contrast can be accelerated by applying a T1-weighted fast gradient echo technique, acceleration of the T2-weighted contrast is not as straightforward.Methods: In this work, the combination of a T2 preparation and a conventional fast gradient echo technique (T2P-3DGE) was evaluated for rapid acquisition of a T2-weighted image contrast. Acquisition parameters were optimized in an initial in vitro study in direct comparison to the conventional T2-weighted TSE (T2W-3DTSE) technique. Subsequently, the T2P-3DGE technique was evaluated in vivo.Results: In direct comparison, the T2P-3DGE sequence provided similar T2 contrast as the respective T2W-3DTSE sequence. After correction of an observed intensity offset, most likely caused by the additional T1-weighting of the T2P-3DGE sequence, no significant difference between the two T2-weighted sequences were observed in phantom data. The good correlation of the image contrast between the two sequences was confirmed in the initial in-vivo study, proving a potential reduction of the scan time for T2P-3DGE to 25% of the respective T2W-3DTSE technique.Conclusion: The in vitro as well as the in vivo results clearly indicate the potential of the T2P-3DGE technique for providing similar T2 image contrast as in the conventional techniques. Thereby, the acquisition times could be substantially reduced to about 25% of the respective 3D-TSE technique. [ABSTRACT FROM AUTHOR]

The aim of the present study was to determine whether preoperative three-dimensional (3D) fast spin-echo (FSE) T1-weighted magnetic resonance (MR) plaque imaging for severely stenotic cervical carotid arteries could accurately predict the development of artery-to-artery emboli during exposure of the carotid arteries in carotid endarterectomy (CEA). Seventy-five patients underwent preoperative MR plaque imaging and CEA under transcranial Doppler ultrasonography of the ipsilateral middle cerebral artery. On reformatted axialMRimage slices showing the maximum plaque occupation rate (POR) and maximum plaque intensity for each patient, the contrast ratio (CR) was calculated by dividing the internal carotid artery plaque signal intensity by the sternocleidomastoid muscle signal intensity. For all patients, the area under the receiver operating characteristic curve (AUC)--used to discriminate between the presence and absence of microembolic signals--was significantly greater for the CR on the axial image with maximum plaque intensity (CRmax intensity) (0.941) than for that with the maximum POR (0.885) (p < 0.05). For 32 patients in whom both the maximum POR and the maximum plaque density were identified, the AUCs for the CR were 1.000. Preoperative 3D FSE T1-weighted MR plaque imaging accurately predicts the development of artery-to-artery emboli during exposure of the carotid arteries in CEA. [ABSTRACT FROM AUTHOR]

As a major application domain of vascular ultrasound, the carotid artery has long been the subject of anthropomorphic phantom design. It is nevertheless not trivial to develop walled carotid phantoms that are compatible for use in integrative imaging of carotid wall motion and flow dynamics. In this paper, we present a novel phantom design protocol that can enable efficient fabrication of walled carotid bifurcation phantoms with: 1) high acoustic compatibility; 2) artery-like vessel elasticity; and 3) stenotic narrowing feature. Our protocol first involved direct fabrication of the vessel core and an outer mold using computer-aided design tools and 3-D printing technology; these built parts were then used to construct an elastic vessel tube through investment casting of a polyvinyl alcohol containing mixture, and an agar-gelatin tissue mimicking slab was formed around the vessel tube. For demonstration, we applied our protocol to develop a set of healthy and stenosed (25%, 50%, and 75%) carotid bifurcation phantoms. Plane wave imaging experiments were performed on these phantoms using an ultrasound scanner with channel-level configurability. Results show that the wall motion dynamics of our phantoms agreed with pulse wave propagation in an elastic vessel (pulse wave velocity of 4.67 ± 0.71 m/s measured at the common carotid artery), and their flow dynamics matched the expected ones in healthy and stenosed bifurcation (recirculation and flow jet formation observed). Integrative imaging of vessel wall motion and blood flow dynamics in our phantoms was also demonstrated, from which we observed fluid-structure interaction differences between healthy and diseased bifurcation phantoms. These findings show that the walled bifurcation phantoms developed with our new protocol are useful in vascular imaging studies that individually or jointly assess wall motion and flow dynamics. [ABSTRACT FROM AUTHOR]

A tortuous common carotid artery poses a high risk of injury during tracheotomy. Preoperative diagnosis is therefore important to avoid serious complications. We found four cases of tortuous common carotid artery during an anatomical dissection course for students. The first case was a 91-year-old woman who had bilateral tortuous common carotid arteries without arteriosclerosis. Case 2 was a 78-year-old woman who had bilateral tortuous common carotid arteries without arteriosclerosis. Case 3 was an 86-year-old woman who died from bladder cancer and who also had a right tortuous common carotid artery without arteriosclerosis. Case 4 was an 89-year-old woman who had bilateral tortuous common carotid arteries and a tortuous brachiocephalic artery with severe arteriosclerosis. Case 4 was also examined using computed tomography to evaluate the arteriosclerosis. Computed tomography revealed severe calcification of the vascular wall, which was confirmed in the aortic arch and origins of its branches. In all four cases, the tortuosity was located below the level of the thyroid gland. Based on prior study results indicating that fusion between the carotid sheath and visceral fascia was often evident at the level of the thyroid gland, we speculated that the major region in which tortuosity occurs is at the same level or inferior to the level of the thyroid gland. [ABSTRACT FROM AUTHOR]

Carotid plaque ulceration is a well-established feature of vulnerability, associated with high risk for neurological symptoms. From a pathogenetic point of view, the mechanism responsible for occurrence of symptomatology relies on the aggregation of platelets within the ulcer cavity, activation of coagulation mechanism, formation of thrombus and arterioarterial embolization of thrombotic material in the central nervous system. Many imaging modalities including unenhanced ultrasound, computed tomographic angiography and magnetic resonance angiography have been used to image and diagnose carotid plaque ulceration with varying success. Contrast-enhanced ultrasound has been recently introduced in the study of carotid disease offering improved flow visualization and better plaque surface delineation. We present a case where contrastenhanced ultrasound visualized the swirling pattern of movement of the microbubbles within the ulcer cavity. These findings illustrate the underlying hemodynamic mechanism of arterio-arterial embolization and can be proposed as a new finding of plaque ulcerations on contrast-enhanced ultrasound. [ABSTRACT FROM AUTHOR]

An ultrasonic image speckle noise removal method by using total least squares model is proposed and applied onto images of cardiovascular structures such as the carotid artery. On the basis of the least squares principle, the related principle of minimum square method is applied to cardiac ultrasound image speckle noise removal process to establish the model of total least squares, orthogonal projection transformation processing is utilized for the output of the model, and the denoising processing for the cardiac ultrasound image speckle noise is realized. Experimental results show that the improved algorithm can greatly improve the resolution of the image, and meet the needs of clinical medical diagnosis and treatment of the cardiovascular system for the head and neck. Furthermore, the success in imaging of carotid arteries has strong implications in neurological complications such as stroke. [ABSTRACT FROM AUTHOR]

Purpose: The study aimed to explore whether GSM based on 3D-ultrasound could predict rupture of carotid plaques and to quantitatively evaluate the vulnerability of carotid plaques. Materials and Methods: 22 Patients with carotid plaques enrolled received 3D-US and 3.0T MRI examinations with intervals less than 48h. Images from two modalities were compared plane by plane. Based on the MRI analysis of plaques tissue compositions, images were divided into 4 groups: fibrous group, lipid core group, calcification group and hybrid group. GSM differences among groups were analyzed and 95% CI was calculated. Based on CAS(carotid atherosclerosis score)system, MRI images were divided into low risk group, medium-low risk group, medium-high risk group and high risk group. GSM differences were compared among groups and 95% CI was calculated. The correlation between GSM and LRNC% (lipid-rich necrotic core%) was analyzed in medium-high risk group and high risk group. Coefficient of variation(CoV) was used to compare the reproducibility of GSM in calcification group and lipid core group. Results: A total of 164 images were matched between 3D-US and MRI. In the classification of plaque tissue composition, GSM was the highest in calcification group (n=29, 95%CI: 57.28-70.38) with a significant difference from other groups, whereas the lowest in lipid core group (n=78, 95% CI:41.79-49.36), but with no significance compared with the fibrous group and hybrid group. In CAS system, GSM was the lowest in high risk group (n=19, 95% CI: 26.44-36.56) and there were significant differences among each group (p<0.05). In high risk group and medium-high risk group, GSM was negatively correlated with lipid core ratio (r=-0.46, p=0.003). CoV of GSM in the calcification group(10.87%) was better than in lipid core group(13.02%), both of them were acceptable. Conclusion: GSM obtained by 3D-US VPQ could evaluate the plaque vulnerability and be served as a new promising method to predict plaque rupture. [ABSTRACT FROM AUTHOR]

Background/Aim. Increasing evidence points to the inflammatory character of atherosclerosis and several parameters of inflammation have been proposed as cerebrovascular risk markers. The objective of the research was to examine the connection of serum inflammatory parameters and ultrasound (US) characteristics of the structure and size of carotid plaque. We assumed that the number of leukocytes (Le) was an indicator of carotid plaque instability and an increased risk of stroke. Methods. Serum inflammatory parameters: erythrocyte sedimentation rate in the first (ESR I) and second hour (ESR II), the number of Le, high sensitivity C-reactive protein (hsCRP) and fibrinogen were measured by standard methods. All the subjects (n = 75) were divided into 3 groups (symptomatic, asymptomatic and control). US evaluation of extracranial carotid arteries was performed in a duplex system. Plaques were classified into categories according to stenosis percentage (⩾ 50%, < 50%) and pursuant to echomorphological characteristics (Gray- Weale classification). In the subjects with stroke an ischemic lesion was confirmed by computed tomography. Results. The average values of biochemical parameters in the symptomatic group were: ESR I 29.57 ± 29.87 cm, ESR II 51.60 ± 36.87 cm, the number of Le 10.10 ± 3.20 ' 10-9 U/L, hs- CRP 8.15 ± 5.50 mg/L and fibrinogen 4.03 ± 0.70 g/L. The average values of all testing biochemical parameters in symptomatic patients were significantly higher than in the asymptomatic ones and the control group: for ESR I (p < 0.05) and ESR II (p < 0.05); for the number of Le (p < 0.001); for hsCRP (p < 0.001) and fibrinogen (p < 0.001). Category I of echomorphological characteristics in the symptomatic group was present in 66.7% of the cases and it was significantly higher than in the asymptomatic (40.0%; p < 0.05) and the control group (20.0%; p < 0.01). Univariate logistic regression analysis confirmed that all testing biochemical parameters are indicators of stroke risk. Multivariate logistic regression analysis confirmed a statistically significant correlation of the number of Le and stroke risk, while the increase in the value by a unit of measurement was associated with the growth of risk by 3.22 times (from 1.67 to 6.22). Conclusion. The number of Le is associated with the phenomenon of carotid plaque instability and may be a useful additional marker of increased risk for developing acute cerebral infarction. [ABSTRACT FROM AUTHOR]

Objectives: To assess the performance of a simplified MRI protocol consisting of a contrast-enhanced three-dimensional MR angiography (CE-MRA) in association with a post-contrast T1-weighted sequence (T1WIV) for the detection of HNPGLs in SDHx mutation carriers.Methods: This retrospective sub-study is based on the multicenter PGL.EVA cohort, which prospectively enrolled SDHx mutation carriers from 2005 to 2009; 157 index cases or relatives were included. CE-MRA and the T1WIV images were read solely with knowledge of the clinical data but blind to the diagnosis. Sensitivity, specificity and likelihood ratios for the simplified MRI protocol were compared to the full MRI protocol reading results and to the gold standard status obtained through the consensus of an expert committee.Results: The sensitivity and specificity of the readings of the simplified MRI protocol were, respectively, 88.7 % (95 % CI = 78.1-95.3) and 93.7 % (95 % CI = 86.8-97.7) versus 80.7 % (95 % CI = 68.6-89.6) and 94.7 % (95 % CI = 88.1-98.3) for the readings of the full MRI protocol.Conclusions: The simplified post-contrast MRI with shorter duration (5 to 10 minutes) showed no performance difference compared to the lengthy standard full MRI and can be proposed for the detection of head and neck paragangliomas (HNPGLs) in SDHx mutation carriers.Key Points: • Rapid angio-MRI protocol and the usual lengthy protocol show equal diagnostic performance. • The CE-MRA is the key sequence for the detection of HNPGLs. • The T1WIV sequence assists in localizing HNPGLs. [ABSTRACT FROM AUTHOR]

Introduction: The present study was aimed to assess the in vivo hamster pial microvessel alterations due to 30 min transient bilateral common carotid artery occlusion (BCCAO) and reperfusion (60 min); moreover, the neuroprotective effects of Vaccinium myrtillus extract, containing 34.7% of anthocyanins, were investigated. Materials and Methods: Two groups of male hamsters were used: the first fed with control diet and the other with Vaccinium myrtillus supplemented diet. Hamster pial microcirculation was visualized by fluorescence microscopy through an open cranial window. Pial arterioles were classified according to Strahler’s method. Results: In age-matched control diet-fed hamsters, BCCAO caused a decrease in diameter of all arterioles. At the end of reperfusion, the reduction of diameter in order 3 arterioles was by 8.4 ± 3.1%, 10.8 ± 2.3% and 12.1 ± 1.1% of baseline in the 2, 4 and 6 month control diet-fed hamsters, respectively. Microvascular permeability and leukocyte adhesion were markedly enhanced, while perfused capillary length (PCL) decreased. The response to acetylcholine and papaverine topical application was impaired; 2’-7’-dichlorofluoresceine-diacetate assay demonstrated a significant ROS production. At the end of BCCAO, in age-matched Vaccinium myrtillussupplemented diet-fed hamsters, the arteriolar diameter did not significantly change compared to baseline. After 60 min reperfusion, order 3 arterioles dilated by 9.3 ± 2.4%, 10.6 ± 3.1% and 11.8 ± 2.7% of baseline in the 2, 4 and 6 month Vaccinium myrtillus supplemented diet-fed hamsters, respectively. Microvascular leakage and leukocyte adhesion were significantly reduced in all groups according to the time-dependent treatment, when compared with the age-matched control diet-fed hamsters. Similarly, the reduction in PCL was progressively prevented. Finally, the response to acetylcholine and papaverine topical application was preserved and there was no significant increase in ROS production in all groups. Conclusions: In conclusion, Vaccinium myrtillusextract protected pial microcirculation during hypoperfusion-reperfusion, preventing vasoconstriction, microvascular permeability, leukocyte adhesion, reduction in PCL and preserving the endothelium function. [ABSTRACT FROM AUTHOR]

Purpose: Carotid artery diseases due to plaque buildup at the carotid bifurcation are a leading cause of stroke. Accurate plaque quantification and characterization of plaque composition and morphology by magnetic resonance imaging(MRI) is essential to identifying high-risk patients. Difficulties in detecting plaque, which is physically small, and the unique physiological structure of the carotid artery make use of a radio frequency (RF) coil array with high resolution, large longitudinal coverage, and deep penetration ideal for clinical examinations. The goal of this project was to design and fabricate a sensitive RF coil array with sufficient imaging coverage and signal-to-noise ratio(SNR) for carotid arteryimaging at 3 T. Methods: Based on clinical requirements and the anatomical structure of the human carotid artery, an 8-channel carotid coil array was designed and fabricated for 3 T MRI of the carotid artery in humans. The performance of the proposed 8-channel carotid coil array was validated through bench tests and MR imaging experiments on a 3 T whole body MRI scanner. Its performance was also compared experimentally to the performance of a commercial 4-channel phased array carotid coil designed by Machnet BV (Machnet BV coil, Roden, Netherlands). Results: The 8-channel carotid coil array performed significantly better in imaging the carotid artery than the commercial 4-channel Machnet BV coil in terms of the SNR, coverage, and penetration depth. In parallel imaging, the proposed 8-channel carotid coil array demonstrated a much lower maximum value and average value of the geometry factor in the region of interest. Carotid arteryimages acquired in vivo using the proposed 8-channel carotid arterycoil and the commercial 4-channel Machnet BV coil were also compared, demonstrating the former's potential for clinical diagnosis. Conclusions: Based on the analyses of phantom and in vivoimaging studies, the proposed 8-channel carotid coil array has the potential for use in clinical diagnosis, performing better in terms of SNR,imaging coverage, and penetration depth than the commercial 4-channel carotid arterycoil array at 3 T. In future studies, the proposed 8-channel carotid coil array can also serve as an important part of a large-scale multichannel coil array for imaging the whole carotid artery system, including the extracranial and intracranial arteries. [ABSTRACT FROM AUTHOR]

Objectives: To determine the frequency of carotid atherosclerosis in obese patients having hepatic steatosis and its effect on the development of MI. Design: Crosssectional study. Setting: Department of Radiology Allied Hospital, Faisalabad. Period: From January 2012 to June 2013, Patients and method: A total of 96 patients were included in this study. LOGIC 5 Doppler ultrasound machine was used. B-mode ultrasonography of common carotid arteries was performed on both sides with a 7.5 MHz linear array transducer. Ultrasound was done in supine position & elevation of chest by pillow. Patient head will be turned to the opposite side. Intima media thickness was accessed in the distal wall of common carotid artery of both sides 1.0 cm proximal to carotid bulb. Results: Mean age of the patients was 46.69±11.86 years. Out of 96 patients, 51 (53.1%) were males while remaining 45 patients (46.9%) were females. Presence of carotid atherosclerosis was noted in 96 patients (100.0%). Out of these patients, myocardial infarction was present in 81 patients (84.4%). Mean BMI was 30.67±0.47, mean weight was 91.86±7.57 Kg and intima media thickness was 0.84±0.12 mm. Conclusion Prevalence of atherosclerotic changes in carotid arteries detected by Doppler ultrasound among obese patients having hepatic steatosis and its effect on the development of MI is remarkable [ABSTRACT FROM AUTHOR]

Objective: Duplex US (DUS) is increasingly utilised as a first-line investigation for the assessment of carotid disease. For clinical decision-making, DUS assessment must be accurate and reproducible to ensure reliability. We aimed to investigate the variability in peak systolic velocity (PSV) measurement in a multi-site vascular network. Methods: DUS measurements of PSV were taken from continuous and pulsatile flow, generated by a high fidelity phantom, by 12 experienced vascular scientists across four hospitals. Participants were blinded to the actual PSV value (50 cm/s). Results: We observed an average error of 13.2% (± 8.3) and 11.6% (± 7.5) in PSV measurements taken from pulsatile and continuous waveforms, respectively. Measurements of PSV using the pulsatile waveform demonstrated statistically significant variation across all hospitals; ((hospital/mean) A 43.9 cm/s, B 61.7 cm/s, C 57.4 cm/s, D 47.7 cm/s, p=0.001). Further analysis demonstrated statistically significant variation in 4 instrumentation-related factors when measuring from a pulsatile waveform (Doppler angle, angle of insonation, velocity range, scale range). Conclusion: We observed a significant level of error and variation in PSV measurements across four sites within our vascular network. Variation in instrumentation-related factors may be accountable for this. In light of the centralisation of vascular services, it is increasingly important to unify and implement scanning protocols in order to reduce error and inter-site variability. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to evaluate the clinical features of hyperdense internal carotid artery sign (HICAS), hyperdense middle cerebral artery sign (HMCAS) and MCA dot sign to understand their effect on the outcomes of acute ischemic stroke patients treated with intravenous recombinant tissue plasminogen activator (iv rtPA). Methods: Computed tomography (CT) scans, clinical features and outcomes of 252 patients with anterior circulation acute ischemic stroke treated with iv rtPA were evaluated. Initial CT scans were evaluated for hyperdense artery sign (HAS). Recanalization was evaluated with transcranial Doppler (TCD) in all available patients. Results: 99 of 252 patients had HAS; 12 had HICAS, 64 had HMCAS and 23 had MCA dot sign. None of the HICAS+ patients had a favorable outcome at three months. HMCAS+ patients achieved significantly less favorable outcomes. Mortality increased significantly in HICAS+ and HMCAS+ patients. MCA dot sign did not make a significant difference on baseline neurological status, recanalization, favorable outcome or mortality. At three months, there was no significant differences between HICAS and HMCAS whereas the MCA dot sign patients had better mRS scores compared with HICAS and HMCAS patients. HMCAS presence, baseline glucose levels and baseline NIHSS scores were all independent predictors of poor outcome. Conclusion: In acute ischemic stroke patients treated with iv rtPA, the presence of HICAS or HMCAS was found to be associated with insufficient recanalization and poor outcome, whereas MCA dot sign was a different entity and did not significantly influence the clinical course or outcome. [ABSTRACT FROM AUTHOR]

Carotid artery atherosclerosis is an important source of mortality and morbidity in the Western world with significant socioeconomic implications. The quest for the early identification of the vulnerable carotid plaque is already in its third decade and traditional measures, such as the sonographic degree of stenosis, are not selective enough to distinguish those who would really benefit from a carotid endarterectomy. MRI of the carotid plaque enables the visualization of plaque composition and specific plaque components that have been linked to a higher risk of subsequent embolic events. Blood suppressed T1 and T2 weighted and proton density-weighted fast spin echo, gradient echo and time-of-flight sequences are typically used to quantify plaque components such as lipid-rich necrotic core, intraplaque haemorrhage, calcification and surface defects including erosion, disruption and ulceration. The purpose of this article is to review the most important recent advances in MRI technology to enable better diagnostic carotid imaging. [ABSTRACT FROM AUTHOR]

Objective: To investigate the incidence of carotid artery (CA) and vertebral artery (VA) stenosis by contrast-enhanced MR angiography (CE-MRA) in patients with nasopharyngeal carcinoma (NPC) after radiotherapy. Methods: 72 patients with NPC after radiotherapy more than 3?years ago were recruited as irradiation group to investigate the incidence and degree of CA and VA stenosis by CE-MRA. The results were compared with those of the control group, which comprised 50 newly diagnosed patients with NPC who had not received radiotherapy. Results: There was a higher incidence of CA and VA stenosis in the irradiation group than in the control group in terms of patient number as well as vessel involvement. The incidence of significant (>50%) CA and VA stenosis, except for the basilar artery, was also higher in the irradiation group than in the control group. The most commonly detected stenosis in the irradiation group was found in the internal CA (ICA) and VA, followed by the external CA and common CA (CCA). CCA and/or ICA (CCA/ICA) stenosis was present in 67 (93.1%) of 72 patients, with 27 (37.5%) patients having significant CCA/ICA stenosis. The statistical analysis demonstrated that age at receiving CE-MRA scanning and time interval from radiotherapy were the independent predictors of significant CCA/ICA stenosis. Conclusion: The CE-MRA scanning results showed that the incidence of stenosis seems to exist in a wider range of CAs and VAs in the patients with NPC after radiotherapy than in the patients who had not received radiotherapy, and the incidence of significant CCA/ICA stenosis is higher in patients with older age and longer interval from radiotherapy. Advances in knowledge: Radiation-induced CA and VA stenosis exists widely in patients with NPC after radiotherapy, and its prevalence is more common in patients with older age and longer interval from radiotherapy. [ABSTRACT FROM AUTHOR]

Background: Both airflow limitation and smoking are established cardiovascular risk factors. However, their interaction as risk factors for the development of atherosclerosis in coronary artery disease patients remains unclear. Objectives: To evaluate the effect of the interaction between airflow limitation and smoking status on the severity of carotid atherosclerosis. Methods: We categorized the 234 enrolled patients with coronary artery disease into four groups: never-smokers with normal pulmonary function (group A), never-smokers with airflow limitation (group B), ever-smokers with normal pulmonary function (group C), and ever-smokers with airflow limitation (group D). Results: The prevalence of airflow limitation in the enrolled patients was 23.1% (ever-smokers: 15.8%, never-smokers: 7.3%). The prevalence of severe carotid atherosclerosis was 28.2, 29.4, 41.3, and 45.9%, respectively, in the four groups (group D vs. group A, p = 0.035). Even after multivariate adjusting for confounding factors, ever-smokers with airflow limitation were independently associated with severe carotid atherosclerosis (odds ratio 2.89, 95% confidence interval, 1.19-7.00, p = 0.019). Conclusions: Ever-smokers with airflow limitation were significantly associated with severe carotid atherosclerosis among patients with coronary artery disease. These findings also provide additional insight into the correlation between airflow limitation and poor cardiovascular clinical outcomes. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The current observational study was conducted to evaluate the morphology of extracranial parts of carotid arteries by colour doppler in patients of stroke and to assess the peak systolic velocity ratio of internal carotid artery/common carotid artery and its utility in diagnosis of the carotid arterial disease. Duplex ultrasound is an inexpensive, non-invasive method that can provide functional and anatomical information about vessel stenosis and plaque morphology. It is a sensitive method for detection of atherosclerotic plaque and provides considerable information about the extent and severityof plaque as well as the resulting diminution of arterial lumen.The study of Colour Doppler of carotid arteries was carried on 35 patients presenting with stroke. The data gathered included grey scale and Doppler findings of common carotid, internal carotid and external carotid arteries. In this study, the commonest lesion found was the atherosclerotic plaque. Most common risk factor for increased intima -media thickness of carotid vessel is found in patients with history of smoking > 10 years. Atheromatous plaque was most commonly found in the left carotid and bilateral system (41.1%). Most common site for atheromatous plaque was found to be carotid bifurcation (48.5%). Significant stenosis (i.e. >40%) was found in 24(64%) of the cases. Peak systolic velocity ratio showed significant stenosis in 24 (68.5%) of patients. The role of carotid Doppler in detecting the site and morphology of atherosclerotic plaque with quantifying the amount of stenosis is very well-justified. In addition carotid Doppler can also be used to assess the prognosis in potential symptomatic and asymptomatic patients with one or the other risk factors for cerebrovascular disease. [ABSTRACT FROM AUTHOR]

Ischemic stroke from thromboembolic sources is linked to carotid artery atherosclerotic disease with a trend toward medical management in asymptomatic patients. Extent of disease is currently diagnosed by non-invasive imaging techniques that measure luminal stenosis, but it has been suggested that a better biomarker for determining risk of future thromboembolic events is plaque morphology and composition. Specifically, plaques that are composed of mechanically soft lipid/necrotic regions covered by thin fibrous caps are the most vulnerable to rupture. An ultrasound technique that non-invasively interrogates the mechanical properties of soft tissue, called acoustic radiation force impulse (ARFI) imaging, has been developed as a new modality for atherosclerotic plaque characterization using phantoms and atherosclerotic pigs, but the technique has yet to be validated in vivo in humans. In this preliminary study, in vivo ARFI imaging is presented in a case study format for four patients undergoing clinically indicated carotid endarterectomy and compared with histology. In two type Va plaques, characterized by lipid/necrotic cores covered by fibrous caps, mean ARFI displacements in focal regions were high relative to the surrounding plaque material, suggesting soft features were covered by stiffer layers within the plaques. In two type Vb plaques, characterized by heavy calcification, mean ARFI peak displacements were low relative to the surrounding plaque and arterial wall, suggesting stiff tissue. This pilot study illustrates the feasibility and challenges of transcutaneous ARFI for characterizing the material and structural composition of carotid atherosclerotic plaques via mechanical properties, in humans, in vivo . [ABSTRACT FROM AUTHOR]

The pathophysiology of ischemic leukoaraiosis (ILA) is unknown. It was recently found that ILA patients have increased aortic stiffness. Carotid stiffness is a more specific parameter and could have value as a non-invasive diagnostic value for ILA. Therefore, using color-coded duplex sonography, we compared local carotid stiffness parameters of 59 patients with ILA with those of 45 well-matched controls. The diagnosis of ILA was based on exclusion of other causes of white matter changes seen on magnetic resonance imaging. Pulse wave velocity β (PWVβ, m/s), pressure–strain elasticity modulus ( E p , kPa), β index and augmentation index ( A ix , %) values were higher and arterial compliance (AC, mm 2 /kPa) values were lower in the ILA group; however, only E p and PWVβ reached statistical significance ( p ≤ 0.05). β, E p and PWVβ exhibited an increasing trend with higher Fazekas score, though only E p reached significance ( p = 0.05). The main conclusion was that E p and PWVβ could have a diagnostic role in patients with ILA. [ABSTRACT FROM AUTHOR]

Ehlers-Danlos syndrome (EDS) type IV is a collagen vascular disease with an autosomal dominant inheritance caused by COL3A1 mutation. Patients with EDS type IV can present with organ rupture, spontaneous arterial dissections and ruptured aneurysms. Because of their propensity to form arterial dissections, aneurysms and rupture, they can develop carotid- cavernous fistula (CCF) after minor trauma or spontaneously. In EDS, it has been reported that even conventional catheter diagnostic angiography may result in large artery dissections and vessel rupture. In addition, the treatment of CCF in EDS type IV can result in up to 59% mortality after initial treatment, of which 23% is attributed to direct complications of treatment. We present the case of a patient with EDS type IV who previously had spontaneous dissection and multiple pseudoaneurysms of both the iliac and femoral arteries and the distal abdominal aorta. Several years later the patient developed a direct type A CCF which was successfully treated with endovascular embolization using a transvenous approach with detachable coils. The literature pertaining to CCF in EDS type IV and its treatment is reviewed. [ABSTRACT FROM AUTHOR]

Aims/Introduction Measurements of plaque echogenicity, the gray-scale median ( GSM), were shown to correlate inversely with risk factors for cerebro-cardiovascular disease ( CVD). The eicosapentaenoic acid ( EPA)/arachidonic acid ( AA) ratio is a potential predictor of CVD risk. In the present study, we assessed the usefulness of carotid plaque GSM values and EPA/AA ratios in atherosclerotic diabetics. Materials and Methods A total of 84 type 2 diabetics with carotid artery plaques were enrolled. On admission, platelet aggregation and lipid profiles, including EPA and AA, were examined. Using ultrasound, mean intima media thickness and plaque score were measured in carotid arteries. Plaque echogenicity was evaluated using computer-assisted quantification of GSM. The patients were then further observed for approximately 3 years. Results Gray-scale median was found to be a good marker of CVD events. On multivariate logistic regression analysis, GSM <32 and plaque score ≥5 were significantly associated with past history and onset of CVD during the follow-up period, the odds ratios being 7.730 ( P = 0.014) and 4.601 ( P = 0.046), respectively. EPA/AA showed a significant correlation with GSM ( P = 0.012) and high-density lipoprotein cholesterol ( P = 0.039), and an inverse correlation with platelet aggregation ( P = 0.046) and triglyceride ( P = 0.020). Although most patients with CVD had both low GSM and low EPA/AA values, an association of EPA/AA with CVD events could not be statistically confirmed. Conclusions The present results suggest the GSM value to be useful as a reference index for CVD events in high-risk atherosclerotic diabetics. Associations of the EPA/AA ratio with known CVD risk factors warrant a larger and more extensive study to show the usefulness of this parameter. [ABSTRACT FROM AUTHOR]

In Italy the vast majority of TIA and minor strokes are seen in the A&E. Early diagnosis and management of TIA and minor stroke in this setting is habitually difficult and often lead to cost-ineffective hospital admissions. We set up an ultra-rapid TIA service run by neurovascular physicians based on early specialist assessment and ultrasound vascular imaging. We audit the clinical effectiveness and feasibility of the service and the impact of this service on TIA and minor strokes hospital admissions. We compared the rate of TIA and minor stroke admissions/discharges in the year before (T0) and in the year during which the TIA service was operating (T1). At T1 57 patients had specialist evaluation and 51 (89.5 %) of them were discharged home. Two (3.5 %) patients had recurrent symptoms after discharge. Seven had a pathological carotid Doppler ultrasound. Four of them had hospital admission and subsequent carotid endoarterectomy within a week. Taking the whole neurology department into consideration at T1 there was a 30-41 % reduction in discharges of patients with TIA or minor stroke. Taking the stroke unit section into consideration at T1 there was a 25 % reduction in admissions of patients with NIHSS score <4 and 40 % reduction in admissions of patients with Barthel Index above 80. The model of TIA service we implemented based on ultra-rapid stroke physician assessment and carotid ultrasound investigation is feasible and clinically valid. Indirect evidence suggests that it reduced the rate of expensive TIA/minor stroke hospital admissions. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate tracking performance when an extra reference block is added to a basic block-matching method, where the two reference blocks originate from two consecutive ultrasound frames. The use of an extra reference block was evaluated for two putative benefits: (i) an increase in tracking performance while maintaining the size of the reference blocks, evaluated using in silico and phantom cine loops; (ii) a reduction in the size of the reference blocks while maintaining the tracking performance, evaluated using in vivo cine loops of the common carotid artery where the longitudinal movement of the wall was estimated. The results indicated that tracking accuracy improved (mean = 48%, p < 0.005 [ in silico ]; mean = 43%, p < 0.01 [phantom]), and there was a reduction in size of the reference blocks while maintaining tracking performance (mean = 19%, p < 0.01 [ in vivo ]). This novel method will facilitate further exploration of the longitudinal movement of the arterial wall. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the clinical role of the presence of external carotid artery (ECA) plaque on all-cause mortality in patients without internal carotid artery (ICA) or common carotid artery (CCA) plaque. The study is investigated by Doppler waveforms, ultrasonography, and statistical analysis. Results show that the presence of ECA plaque is considered an independent predictor of all-cause mortality.

Noninvasive imaging methods are required to monitor the inflammatory content of atherosclerotic plaques. FEDAA1106 (N-(5-fluoro-2-phenoxyphenyl)-N-(2-(2-fluoroethoxy)-5-methoxybenzyl) acetamide) is a selective ligand for TSPO-18kDa (also known as peripheral benzodiazepine receptor), which is expressed by activated macrophages. We compared 18F-FEDAA1106 and 2-deoxy-2-[18F]fluoro-D-glucose (18F-FDG, a marker of glucose metabolism) for positron emission tomographic (PET) imaging of vascular inflammation. This was tested using a murine model in which focal inflammation was induced in the carotid artery via placement of a constrictive cuff. Immunostaining revealed CD68-positive cells (macrophages) at a disturbed flow site located downstream from the cuff. Dynamic PET imaging using 18F-FEDAA1106 or 18F-FDG was registered to anatomic data generated by computed tomographic (CT)/CT angiography. Standardized uptake values were significantly increased at cuffed compared to contralateral arteries using either 18F-FEDAA1106 (p < .01) or FDG (p < .05). However, the 18F-FEDAA1106 signal was significantly higher at the inflamed disturbed flow region compared to the noninflamed uniform flow regions, whereas differences in FDG uptake were less distinct. We conclude that 18F-FEDAA1106 can be used in vivo for detection of vascular inflammation. Moreover, the signal pattern of 18F-FEDAA1106 corresponded with vascular inflammation more specifically than FDG uptake. [ABSTRACT FROM AUTHOR]

Idiopathic carotidynia is a syndrome characterized by pain and tenderness over the carotid artery without an associated structural luminal abnormality. Controversy exists over whether this is a distinct disease entity or merely a symptom attributable to other causes of neck pain, such as carotid dissection or vasculitis. A 50-year-old woman presented with sudden-onset right neck pain. Imaging studies demonstrated transmural inflammation of the proximal internal carotid artery, without evidence of intraluminal pathology. The patient was placed on low-dose aspirin and ibuprofen. Her symptoms resolved within a week. At 3-month follow-up, her carotid artery appeared normal on duplex ultrasonography. [ABSTRACT FROM AUTHOR]

Abstract: A new approach is introduced for the automatic detection of the lumen axis of the common carotid artery in B-mode ultrasound images. The image is smoothed using a Gaussian filter and then a dynamic programming scheme extracts the dominant paths of local minima of the intensity and the dominant paths of local maxima of the gradient magnitude with the gradient pointing downwards. Since these paths are possible estimates of the lumen axis and the far wall of a blood vessel, respectively, they are grouped together into pairs. Then, a pattern of two features is computed from each pair of paths and used as input to a linear discriminant classifier in order to select the pair of paths that correspond to the common carotid artery. The estimated lumen axis is the path of local minima of the intensity that belongs to the selected pair of paths. The proposed method is suited to real time processing, no user interaction is required and the number of parameters is minimal and easy to determine. The validation was performed using two datasets, with a total of 199 images, and has shown a success rate of 99.5% (100% if only the carotid regions for which a ground truth is available are considered). The datasets have a large diversity of images, including cases of arteries with plaque and images with heavy noise, text or other graphical markings inside the artery region. [Copyright &y& Elsevier]

Abstract: Color flow imaging and pulsed wave (PW) Doppler are important diagnostic tools in the examination of patients with carotid artery disease. However, measurement of the true peak systolic velocity is dependent on sample volume placement and the operator's ability to provide an educated guess of the flow direction. Using plane wave transmissions and a duplex imaging scheme, we present an all-in-one modality that provides both vector velocity and spectral Doppler imaging from one acquisition, in addition to separate B-mode images of sufficient quality. The vector Doppler information was used to provide automatically calibrated (angle-corrected) PW Doppler spectra at every image point. It was demonstrated that the combined information can be used to generate spatial maps of the peak systolic velocity, highlighting regions of high velocity and the extent of the stenotic region, which could be used to automate work flow as well as improve the accuracy of measurement of true peak systolic velocity. The modality was tested in a small group (N = 12) of patients with carotid artery disease. PW Doppler, vector velocity and B-mode images could successfully be obtained from a single recording for all patients with a body mass index ranging from 21 to 31 and a carotid depth ranging from 16 to 28 mm. [Copyright &y& Elsevier]

Objectives: To investigate the feasibility of using a single-dose injection protocol in CT angiography (CTA) of the carotid and coronary artery with 320-row multidetector CT. Methods: A total of 82 consecutive patients with suspected carotid artery disease underwent an original CTA protocol aiming at capturing the extra-cranial carotid arteries and coronary arteries simultaneously using 320-row MDCT. The image quality, attenuation, and CNRs of the carotid and coronary arteries were assessed. The lag time (between two separated volumetric acquisitions) was compared between patients with and without cardiac venous opacification (CVO). The contrast medium volume and radiation dose were recorded. Results: The image quality was 99.4 % diagnostic in carotid and 86.9 % in coronary artery segments. The mean attenuation of carotid and coronary arteries ranged from 462.2 Hu to 533.7 Hu, 415.9 Hu to 454.7 Hu respectively. The mean CNR of the carotid and coronary artery ranged from 15.8 to 18.9 and 17.7 to 20.4 respectively. The lag time in patients with and without CVO was 5.75 ± 1.64 s vs. 4.21 ± 1.14 s ( p < 0.05). The mean radiation dose was 6.6 ± 4.1 mSv.The mean contrast media volume was 71.9 ± 9.1 ml. Conclusions: The carotid and coronary artery can be imaged simultaneously via our original single-dose injection CTA protocol using 320-row CT with adequate image quality. Key Points: • Carotid and coronary 320-row CTA can be achieved in a single-dose injection. • Longer coverage was achieved with two or more volumes using 320-row CT. • The single-dose protocol allows a reduced contrast agent dose of about 72 ml. [ABSTRACT FROM AUTHOR]

Abstract: To improve our understanding of the mechanical behavior of human atherosclerotic plaque tissue, fully 3-D geometrical, morphological and dynamical information is essential. For this purpose, four-dimensional (3-D+t) strain imaging using an ultrasound tomography approach (echo-computed tomography) was performed in carotid arteries in vitro. The method was applied to a carotid phantom (CPh), a porcine carotid artery (PC) and human carotid atherosclerotic plaque samples (HC, n = 5). Each sample was subjected to an intraluminal pressure, after which 2-D longitudinal ultrasound images were obtained for 36 angles along the circumferential direction. Local deformations were estimated using a 2-D strain algorithm, and 3-D radial strain data were reconstructed. At systole, median luminal strains of 15% (CPh) and 18% (PC) were found, which is in agreement with the stiffness of the material and applied pressure pulse. The elastographic signal-to-noise ratio was consistent in all directions and ranged from 16 to 36 dB. Furthermore, realistic but more complex strain patterns were found for the HC, with 99th percentile systolic strain values ranging from 0.1% to 18%. [Copyright &y& Elsevier]

Abstract: Objective: Development of a fast 3D high-resolution magnetic resonance imaging (MRI) protocol for improved carotid artery plaque imaging. Methods: Two patients with carotid atherosclerosis disease underwent 3D high-resolution MRI which included time-of-flight and T1-weighted variable flip angle, fast-spin-echo (FSE) imaging, pre- and post-intravenous gadolinium-based contrast agent administration. Results: Good quality images with intrinsic blood suppression were obtained pre- and post-contrast administration using a 3D FSE sequence. The plaque burden, lipid core volume, hemorrhage volume and fibrous cap thickness were well determined. Conclusions: 3D high-resolution MR imaging of carotid plaque using TOF and 3D FSE can achieve high isotropic resolution, large coverage, and excellent image quality within a short acquisition time. [Copyright &y& Elsevier]

Purpose: Involuntary movement is a rare symptom of moyamoya disease (MMD). No consensus has been reached regarding its clinical features and pathogenetic mechanism. Therefore, pediatric MMD patients presenting with involuntary movement were retrospectively analyzed, focusing on the image findings. Methods: A total of 513 patients who were treated for MMD were reviewed. After exclusion of MMD syndromes and those with accompanying conditions related to involuntary movements, five patients (mean age: 11.6 years, range: 5-13 years) were evaluated. Results: All of the patients improved their symptoms rapidly after the indirect bypass operations to the contralateral hemisphere. All remained symptom-free during the long follow-up period. Comprehensive evaluation of the preoperative imaging findings failed to suggest a characteristic feature in common, corresponding to the existing hypotheses or a new hypothesis. Only one patient showed infarction preoperatively, and only one patient showed prominently enhanced collateral vessels in the basal ganglia. Although a decrease in vascular reserve was observed in all patients, the location and laterality were nonspecific. Conclusion: There still appears to be confusion regarding the pathogenetic mechanism of involuntary movement in MMD with no repetitive, established imaging features to explain the phenomenon. Nonetheless, with its excellent response to surgical treatment, clinical awareness of this rare symptom of MMD should be emphasized as a differential diagnosis for secondary movement disorder in children. [ABSTRACT FROM AUTHOR]

Background: Cerebral vasculopathy is a serious complication of sickle cell anemia. Overt strokes are largely due to intracranial arteriopathy, detected by routine transcranial Doppler and largely prevented through chronic transfusions. As extracranial internal carotid artery arteriopathy was considered rare, it has not been routinely assessed in sickle cell anemia. Recent cases of overt strokes associated with stenosis/occlusion of the extracranial portion of the internal carotid artery prompted us to include extracranial internal carotid artery assessment to our transcranial Doppler sonography protocol. Objective: The aim of the study was to perform a cross-sectional study in children with sickle cell anemia to evaluate Doppler flow patterns of the extracranial internal carotid arteries and to assess potential associated factors. Materials and methods: Between June 2011 and April 2012, 435 consecutive stroke-free children with sickle cell anemia (200/235 M/F, median age: 7.9 years) were assessed for extracranial internal carotid artery using a 2-MHz transcranial Doppler sonography probe via a submandibular window during routine transcranial Doppler sonography visits. The course of both extracranial internal carotid artery was assessed by color Doppler mapping, and the highest flow velocity was recorded after insonation of the entire length of the artery and analyzed. Intra- and extracranial MR angiographies were available in 104/435 subjects for comparison. Results: Mean (SD) extracranial internal carotid artery time-averaged mean of maximum velocity was 96 (40) cm/s. Extracranial internal carotid artery tortuosities were echo-detected in 25% cases and were more frequent in boys (33% vs.18%; P < 0.001). Velocity ≥160 cm/s in at least one extracranial internal carotid artery was found in 45 out of 435 patients with sickle cell anemia (10.3%) and was highly predictive of MR angiography stenosis. Simultaneous abnormal intracranial velocity (≥200 cm/s) was recorded in 5/45 patients, while 40 patients had isolated extracranial internal carotid artery velocity ≥160 cm/s. Low hemoglobin (odds ratio: 1.9/g/dL, 95% confidence interval (CI): 1.3-2.9; P = 0.001) and tortuosities (odds ratio: 19.2, 95% CI: 7.1-52.6; P < 0.001) were significant and independent associated factors for isolated extracranial internal carotid artery velocities ≥160 cm/s. Conclusion: Adding extracranial internal carotid artery evaluation via the submandibular window to transcranial Doppler sonograpy allowed us to detect 10.3% patients at risk for extracranial internal carotid arteriopathy. Further studies are needed to evaluate the prognosis of these anomalies. [ABSTRACT FROM AUTHOR]

Atherosclerosis is the leading underlying pathologic process that results in cardiovascular diseases, which represents the main cause of death and disability in the world. The atherosclerotic process is a complex degenerative condition mainly affecting the medium- and large-size arteries, which begins in childhood and may remain unnoticed during decades. The intima-media thickness (IMT) of the common carotid artery (CCA) has emerged as one of the most powerful tool for the evaluation of preclinical atherosclerosis. IMT is measured by means of B-mode ultrasound images, which is a non-invasive and relatively low-cost technique. This paper proposes an effective image segmentation method for the IMT measurement in an automatic way. With this purpose, segmentation is posed as a pattern recognition problem, and a combination of artificial neural networks has been trained to solve this task. In particular, multi-layer perceptrons trained under the scaled conjugate gradient algorithm have been used. The suggested approach is tested on a set of 60 longitudinal ultrasound images of the CCA by comparing the automatic segmentation with four manual tracings. Moreover, the intra- and inter-observer errors have also been assessed. Despite of the simplicity of our approach, several quantitative statistical evaluations have shown its accuracy and robustness. [ABSTRACT FROM AUTHOR]