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BACKGROUND AND PURPOSE: CTA has shown limited accuracy and reliability in distinguishing tandem occlusions and pseudo-occlusions on initial acute stroke imaging. The utility of early and delayed contrast-enhanced MRA in this setting is unknown. We aimed to assess the accuracy and reliability of early and delayed contrast-enhanced MRA for carotid bulb patency in patients with acute ischemic stroke. MATERIALS AND METHODS: We retrospectively reviewed patients who had ICA occlusion and underwent thrombectomy with preprocedural early and delayed contrast-enhanced MRA in a single comprehensive stroke center. During 2 sessions, 10 raters independently assessed 32 cases with early contrast-enhanced MRA (with an additional delayed contrast-enhanced MRA sequence during the second reading session). Their judgments were compared with DSA as a reference standard. Accuracy and interrater agreement were measured. Five raters undertook a third reading session to assess intrarater agreement. RESULTS: Accuracy for the assessment of carotid bulb patency with early contrast-enhanced MRA was limited (69%; 95% CI, 59%–79%), with moderate interrater agreement (κ = 0.42; 95% CI, 0.27–0.55). The second reading with an additional delayed contrast-enhanced MRA sequence improved both accuracy (82%; 95% CI, 73%–91%; P < .001) (raters corrected 43%–77% of incorrect diagnoses with early contrast-enhanced MRA alone; mean = 59%) and interrater agreement (κ = 0.56; 95% CI, 0.41–0.73; P = .07). Intrarater agreement was almost perfect, substantial, and moderate for 3, 1, and 1 raters. CONCLUSIONS: Early contrast-enhanced MRA has limited accuracy and repeatability for the evaluation of carotid bulb patency in acute ischemic stroke. The additional delayed contrast-enhanced MRA sequence may improve accuracy and reliability.

OBJECTIVES To determine how measurements of the internal carotid artery (ICA) cross-sectional area will differ systematically when obtained by grayscale, color Doppler, and power Doppler imaging. METHODS A total of 451 patients had greater than 40% diameter stenosis in at least a single ICA. Anteroposterior and transverse luminal diameters were measured in 609 arteries on grayscale, color, and power Doppler transverse images of the carotid bulb and proximal and distal ICAs. Cross-sectional areas were calculated and compared by a repeated-measures analysis of variance model to assess for significant differences. RESULTS Mean ICA cross-sectional areas ± SDs as measured by grayscale, power Doppler, and color Doppler imaging were 122 ± 81, 122 ± 79, and 125 ± 79 mm2 , respectively. The mean ICA area estimated by color Doppler imaging was significantly greater than that estimated by power Doppler imaging (P

The objectives of this study are to (1) examine the “10-year cardiovascular risk” in the common carotid artery (CCA) versus carotid bulb using an integrated calculator called “AtheroEdge Composite Risk Score 2.0” (AECRS2.0) and (2) evaluate the performance of AECRS2.0 against “conventional cardiovascular risk calculators.” These objectives are met by measuring (1) image-based phenotypes and AECRS2.0 score computation and (2) performance evaluation of AECRS2.0 against 12 conventional cardiovascular risk calculators. The Asian–Indian cohort (n = 379) with type 2 diabetes mellitus (T2DM), chronic kidney disease (CKD), or hypertension were retrospectively analyzed by acquiring the 1516 carotid ultrasound scans (mean age: 55 ± 10.1 years, 67% males, ∼92% with T2DM, ∼83% with CKD [stage 1-5], and 87.5% with hypertension [stage 1-2]). The carotid bulb showed a higher 10-year cardiovascular risk compared to the CCA by 18% ( P < .0001). Patients with T2DM and/or CKD also followed a similar trend. The carotid bulb demonstrated a superior risk assessment compared to CCA in patients with T2DM and/or CKD by showing: (1) ∼13% better than CCA (0.93 vs 0.82, P = .0001) and (2) ∼29% better compared with 12 types of risk conventional calculators (0.93 vs 0.72, P = .06).

Aberrant vertebral artery (VA) origins are uncommon, and those arising from the carotid bulb are exceedingly rare. We report a 79-year-old man with a right thalamic stroke and subsequent amaurosis fugax that was found to have severe right carotid bulb and internal carotid artery stenoses, as well as an aberrant VA arising from the bulb. He underwent carotid endarterectomy including eversion endarterectomy of the VA and had no recurrence of amaurosis fugax or posterior circulation symptoms at the 1-year follow-up. We also present a comprehensive review of the literature, focusing on symptomatic cases and those arising from the carotid bulb.

This chapter includes (1) Occipital artery arising from the carotid bulb, (2) Occipital artery arising from the cervical internal carotid artery, (3) Ascending pharyngeal artery arising from the internal carotid artery, and (4) Persistent stapedial artery (Middle meningeal artery arising from the petrous internal carotid artery). There are 10 figures.

Carotid web (CW) is an atypical form of intimal fibromuscular dysplasia that occurs at the level of the carotid bulb. It is associated with ischemic strokes. The first report of this association was in 1967 and it is currently known to represent a significant percentage of cryptogenic stroke. We report the case of a young female patient with a history of transient ischemic attack who presented a cerebral infarction of the territory of the left middle cerebral artery. The diagnosis of CW was suggested by the findings of the ultrasound carotid duplex and was confirmed by digital subtraction angiography. Likewise, brain magnetic resonance angiography showed an incipient alteration in the morphology of the wall of the left internal carotid artery in its intracranial segment. Aspirin treatment was started and there was no recurrence up to two years of follow-up. CW represents a diagnostic challenge; it should be suspected in young adults with ischemic stroke. In them, studies of the supra-aortic vessels should be performed. Ultrasound carotid duplex can be a useful diagnostic tool.

The carotid bulb has a high density of baroreceptors that play an important role in maintaining blood pressure. We hypothesized that atherosclerosis of the carotid bulb would reflect the severity of orthostatic hypotension more accurately than would atherosclerosis of other carotid artery segments.This cross-sectional study included 198 non-diabetic adults. We measured the cardio-vascular ankle index as an index of arterial stiffness, intima-media thickness in each carotid artery segment (internal carotid artery, carotid bulb, distal and proximal portions, respectively, of the common carotid artery) as a measure of atherosclerosis, and heart rate variability as a measure of cardiac autonomic function. The sit-to-stand test was used to assess severity of orthostatic hypotension.Intima-media thickness of the carotid bulb was correlated with orthostatic systolic blood pressure change (r = -0.218, p = 0.002), cardio-ankle vascular index (r = 0.365, p0.001) and heart rate variability parameters. Multivariate regression analysis revealed that among all of the segments, only intima-media thickness of the carotid bulb was an independent predictor of orthostatic systolic blood pressure change (p = 0.022).Atherosclerosis of the carotid bulb was associated with severity of orthostatic hypotension, arterial stiffening and cardiac autonomic dysfunction than that of other carotid artery segments.

Objective: To evaluate the safety and outcomes of surgical revascularization for patients with symptomatic kinking of the internal carotid artery (ICA). Methods: Twenty-five consecutive patients presented with symptomatic kinking of the ICA and a history of transient ischemic attack (TIA) or stroke were prospectively enrolled in this study. All patients were treated with ICA transection and end-to-side reimplantation at the level of the carotid bulb. Patients were followed up for a median of 32 months. Results: There were no deaths or strokes within the 30 days of the treatment. No postprocedural thrombosis or narrowing of the ipsilateral ICA was observed. One (4%) patient had temporary recurrent nerve palsy, which was completely recovered at 4-week follow-up. One (4%) patient had a myocardial ischemic event. At the end of the 32-month follow-up, 1 (4%) patient developed ipsilateral minor stroke. No recurrent stenosis was detected by Doppler ultrasound. Conclusion: Surgical treatment for isolated, symptomatic kinking of the ICA and a history of TIA or stroke is safe, and the outcomes are acceptable.

Patients with Klippel-Feil syndrome (KFS) have an increased incidence of vascular anomalies as well as vertebral artery (VA) anomalies. In this article, we presented imaging findings of a 15-year-old female patient with KFS with a rare association of extraforaminal cranially ascending right VA that originated from the ipsilateral carotid bulb. Trifurcation of the carotid bulb with VA is a very unusual variation and to the best of our knowledge, right-sided one has not been reported in the literature.

A 52-year-old woman without cardiovascular risk factors presented with an acute middle cerebral artery infarction. An ipsilateral thin, smooth, membrane-like intraluminal filling defect along the posterior wall of the internal carotid bulb compatible with carotid web (CW) was observed on Doppler ultrasound, CT, and magnetic resonance angiography (figure). No other abnormalities were found on extensive diagnostic workup. CW is thought to represent an intimal variant of fibromuscular dysplasia.1,2 Although data are scarce, CW may be associated with increased stroke risk in young patients with cryptogenic anterior circulation infarction and with a high risk of stroke recurrence.2

Background: Carotid web is a shelf-like lesion in the posterior aspect of the internal carotid bulb and represents an intimal variant of fibromuscular dysplasia. Carotid webs have been associated with recurrent strokes and traditionally treated with surgical excision. We report a multicenter experience of stenting in patients with symptomatic carotid webs. Methods: Retrospective review of patients admitted to three comprehensive stroke centers identified to have a carotid web with otherwise negative stroke workup that underwent stenting. A carotid web was defined by the presence of a shelf-like/linear, smooth filling defect in the posterior aspect of the carotid bulb diagnosed by neck CT/MR angiography and confirmed with conventional angiography. Results: Twenty patients with symptomatic (80% Stroke/20% TIA) carotid webs were stented. Median age was 48[41-61] years, 7(35%) were male, and 15(75%) Black. Median NIHSS was 11[2-16] while ASPECTS 8[7-8]. Eight (40%) received intravenous thrombolysis and 10 (50%) thrombectomy. All patients were stented on dual antiplatelets (aspirin and clopidogrel[17] or ticagrelor[3]) at a median 9[4-30]days after the last vascular event. Closed-cell stents were used in 75% of cases (XACT [14] and Wallstent [1]) while open-cell stents in 25% (Acculink[5]). No cases required angioplasty for residual stenosis had to be performed. DIstal embolic protection was used in 19 cases (SpiderFX[18] and Emboshield_NAV6[1]) while proximal protection in 1 (MoMa). No periprocedural events occurred with the exception of two cases of hypotension/bradycardia (one requiring 24-hour vasopressors). No parenchymal hematomas were observed but one patient developed vaginal hemorrhage requiring discontinuation of one antiplatelet at 2 months. Modified Rankin Scale 0-2 (independence) at 90 days was recorded in 95% of patients. Clinical follow-up post stent occurred for a median of 4 [2-12] months and no follow-up cerebrovascular events were noted. Follow-up vascular imaging was performed in 95% patients at a median of 3[2-12]months and were all unremarkable. Conclusions: Stenting for symptomatic carotid web appears to be a valid, safe, and effective alternative to surgical piecemeal resection. Further studies are warranted.

Carotid artery ultrasound is a non-invasive and reproducible technique used for early atherosclerotic assessment. Intimal flap has been described in the presence of dissection or mobile plaque rupture, however presence of carotid thin fluttering bands (TFBs) have not been described yet. To investigate frequency, characteristics and impact of TFBs in carotid lumen of patients who underwent carotid ultrasound scan (CUS). 3341 patients were admitted from January 2009 to January 2014. Patients with history of cerebral ischemia (CI) were excluded. In the cases in which TFBs were observed, a 3-months clinical and CUS follow-up (FU) was performed. TFBs were found in 71 patients (2.1%). The mean age was 63.41 ± 11.20 years (range 42-89). All patients showed a mean increase in intima-media thickness. We identified two subgroups: in 22 patients the TFB was related to a carotid plaque while in 49 no carotid plaque was found. TFB mostly originated in the carotid bulb (88.7%) and was similarly located in carotid arteries (49.3% left-side and 50.7% right-side). CUS and clinical FU were available for all patients (mean duration 25.34 months, median 19). CI occurred in none of the patients. TFB disappeared in 13 patients (18.3%) with no sign or symptoms of CI. In 3 of 49 patients without carotid plaque (6.1%), progressive thickening beneath TFB was observed. TFB is a rare finding. Longer FU is needed to evaluate its prognosis. To date, the pathophysiology is unknown, however it could be related to vascular remodeling.

Ultrasound reports describe carotid plaque as being located within the bulb or bifurcation. These terms are used interchangeably; however they refer to two distinct regions. The purpose of this study was to determine the presence of a bulbous region within the common (CCA), internal (ICA) or external (ECA) carotid arteries by using ultrasound. Ultrasound images were examined from 100 carotid systems from 53 males and 47 females ranging in age from 17–88 years (mean age 65 ± 15 years). An outward dilation, consistent with the expected appearance of a carotid bulb, was observed in the ICA in 49 patients. Nineteen patients had a bulb in both the ECA and ICA. In 10 patients, a bulb was present within both the ICA and CCA. In 5 patients, the CCA, ICA and ECA all contained bulbous regions. A bulb was present only within the CCA in five patients and only within the ECA in three patients. No bulb was present in nine patients. These data reveal that a bulbous region occurs in multiple segments. Defining plaque as being present within the carotid bulb is ambiguous since this applies to more than one vessel. Based on these findings, it is more appropriate to define plaque by using terms such as proximal, mid or distal. Carotid bifurcation refers to a specific anatomic region and would be acceptable as defining the location of disease. However, given carotid bulb variability, the term “carotid bulb” should be removed from common use within carotid duplex interpretations.

Carotid webs are an uncommon cause of recurrent ischaemic strokes. They are considered a form of fibromuscular dysplasia, possibly developmental in origin, with non-inflammatory and non-atherosclerotic features and a characteristic appearance on CT angiography. They have been described as a thin intraluminal filling defect along the posterior wall of the carotid bulb in oblique sagittal reformats and a septum on axial CT angiography. Here we summarize two cases of ischaemic strokes secondary to carotid webs with characteristic images. Detection and awareness of carotid webs and their imaging features among radiologists and physicians are important as it is associated with a high risk of recurrent cerebrovascular events.

BACKGROUND AND PURPOSE: Carotid webs are intraluminal shelf-like filling defects at the carotid bulb with recently recognized implications in patients with recurrent ischemic stroke. We sought to determine whether carotid webs are an under-recognized cause of “cryptogenic” ischemic stroke and to estimate their prevalence in the general population. MATERIALS AND METHODS: A retrospective review of neck CTA studies in young patients with cryptogenic stroke over the past 6 years (n = 33) was performed to determine the prevalence of carotid webs compared with a control group of patients who received neck CTA studies for reasons other than ischemic stroke (n = 63). RESULTS: The prevalence of carotid webs in the cryptogenic stroke population was 21.2% (95% CI, 8.9%–38.9%). Patients with symptomatic carotid webs had a mean age of 38.9 years (range, 30–48 years) and were mostly African American (86%) and women (86%). In contrast, only 1.6% (95% CI, 0%–8.5%) of patients in the control group demonstrated a web. Our findings demonstrate a statistically significant association between carotid webs and ischemic stroke (OR = 16.7; 95% CI, 2.78–320.3; P = .01). CONCLUSIONS: Carotid webs exhibit a strong association with ischemic stroke, and their presence should be suspected in patients lacking other risk factors, particularly African American women.

Introduction: Carotid Web (CW) is a rare form of focal fibromuscular dysplasia that results in an abnormal shelf-like projection of intimal fibrous tissue into the carotid bulb. It is theorized that CW leads to ischemic stroke secondary to blood flow stasis and subsequent embolization. There is uncertainty in diagnosis, prognosis, and optimal management of this uncommon entity. To address this knowledge gap, we performed a systematic literature review (SLR) of CW. Methods: Our literature search for CW and related terms yielded 1017 results. After a preliminary assessment of all 1017 retrieved manuscripts; 72 manuscripts were reviewed in detail. A total of 31 manuscripts met entry criteria and were included in our SLR. We present the demographics, cardiovascular (CV) risk factors, neuroimaging findings, stroke recurrence or stroke free-duration, and treatment modality of CW patients. Results: Our SLR resulted in 104 patients with CW, (median age at presentation: 45.7 [IQR 45-57], 52.3% female). The majority (68.3%) of CW patients did not have CV risk factors, however, 22.2% of patients were smokers. 47.8% of patients suffered recurrent stroke. The majority of patients were ultimately treated with antiplatelet therapy (94.4%) and 21.2% underwent carotid revascularization (4.8% carotid stenting, 16.3% carotid endarterectomy). None of the patients who underwent revascularization had a reported stroke recurrence. See Table. Conclusions: CW is a rare disease leading to ischemic stroke in younger patients without typical CV risk factors. CW patients in our SLR were at extremely high risk for recurrent stroke (47.8%). Aggressive secondary stroke prevention measures are indicated in this patient population, however, the optimal treatment strategies remain unclear. Carotid revascularization may be the definitive treatment for certain patients with CW, but further studies are needed as incomplete reporting and potential publication bias limit our findings.

Introduction: Carotid Webs (also termed “atypical FMD”) are characterized by a focal, intraluminal filling defect along the posterior wall of the carotid bulb. They have been reported in association with recurrent stroke in young patients without atherosclerotic risk factors and may represent an unrecognized and potentially treatable cause of stroke. Stroke mechanism appears to be related to sluggish blood flow and thrombi formation. The purpose of our study was to determine the prevalence of carotid webs in patients with cryptogenic stroke after standard complete stroke evaluation. Methods: Retrospective analysis of all patients under age 55 presenting with ischemic strokes 9/2009- 8/2015. CTA has been found to be reliable in detecting webs, so was chosen as the modality for interpretation. 119 cryptogenic stroke patients were identified; 41 of these had CTA. De-identified CTAs were evaluated on TerraRecon by two experienced, board certified, fellowship trained neuroradiologists, with disagreement adjudicated by a third neuroradiologist. Readers were blinded to age, gender, and laterality of stroke. Results: Carotid webs were identified in 7 (17%) cases. Presenting stroke was on the same side as the carotid web in all cases. One case had superimposed thrombus, zero had atherosclerosis, and zero had classic features of fibromuscular dysplasia. One patient had recurrent strokes in the territory. Mean age of patients with carotid web was 38.3 years (range 30-41) with 6 (86%) women and 1 (14%) male. Five patients (71%) were African American. Discussion: Carotid webs were identified in a significant portion of strokes previously diagnosed as cryptogenic. More research is needed to determine the natural history and optimal treatment of patients with carotid webs and more detailed carotid evaluation to identify webs should be considered as part of the stroke evaluation.

Carotid body tumors (CBT), are rare neoplasms arising from the chemoreceptor cells of the carotid bulb. We report a case of CBT in a 41 year old female, who presented with a painless, pulsatile, gradually progressive lateral neck swelling. Diagnosis was suspected on the basis of history, clinical and radiological examination findings and a successful surgical excision of the tumor was performed. Histopathological examination confirmed the diagnosis of CBT. We also present a brief literature about CBT in terms of its clinical presentation, evaluation and management.

A 64-year-old man was admitted with massive hemoptysis caused by oropharyngeal carcinoma. Angiography revealed active extravasation from the left carotid bulb. Covered stent-graft placement resolved the bleeding, but the patient presented with recurrent hemorrhage two hours later and was treated with another stent-graft.

Tonsillectomy, though a popular surgery, has now downsized to limited indications. Although rare, this surgery may cause trauma to the great vessels leading to life-threatening hemorrhage. The congenitally tortuous internal carotid artery (ICA) is an unusual but important anomaly, especially when it is situated in the tonsillar fossae. About 1%–16% of patients have a surgically vulnerable ICA manifested clinically. Here, we present the first reported case of carotid bulb in the right tonsillar fossa. A 7-year-old female child underwent tonsillectomy for obstructive sleep apnea syndrome. Intraoperatively, she was found to have a carotid bulb in both tonsillar fossae, right more prominent than left one. Computed tomography angiogram confirmed the presence of a prominent carotid bulb in the right tonsillar fossa at the C2level. This case report highlights the importance of a heightened awareness of the anatomic variations of carotid artery, in particular, the carotid bulb. This is of critical significance for a safe tonsillectomy as well as any procedure performed in the oropharyngeal region.

Fibromuscular dysplasia (FMD) is known as rare cause ischemic stroke and usually involves the internal carotid or vertebral arteries in middle age women. A poorly known type of FMD located at the carotid bulb is called atypical fibromuscular dysplasia. We present the case of 3 young black patients suffering from recurrent ischemic strokes in the same middle cerebral artery territory. Computed tomographic angiography and arteriography showed a moderate diaphragmatic stenosis of the carotid bulb. After surgical removal of the dysplasia, postoperative course was uneventful without any recurrence. Pathologic examination confirmed atypical FMD. Carotid-bulb atypical FMD is a rare cause of stroke and concerns mostly young black patients. Surgical approach should be recommended to avoid recurrent stroke.

Automated detection of the carotid bulb edge, which is considered a reference marker for measurements of the cIMT.Automated segment-based cIMT measurement system which estimates the cIMT for different segments of the carotid artery proximal to the bulb edge.Segmental-IMT (sIMT) allows us to measure IMT in 10 mm segments (namely: s1, s2 and s3) proximal to the bulb edge.The proposed fully automated bulb detection system achieved 92.67% precision against ideal bulb edge locations in the bulb transition zone and holds a significant promise for risk stratification tool for carotid disease. Background and objectivesStandardization of the carotid IMT requires a reference marker in ultrasound scans. It has been shown previously that manual reference marker and manually created carotid segments are used for measuring IMT in these segments. Manual methods are tedious, time consuming, subjective, and prone to errors. Bulb edge can be considered as a reference marker for measurements of the cIMT. However, bulb edge can be difficult to locate in ultrasound scans due to: (a) low signal to noise ratio in the bulb region as compared to common carotid artery region; (b) uncertainty of bulb location in craniocaudal direction; and (c) variability in carotid bulb shape and size. This paper presents an automated system (a class of AtheroEdge system from AtheroPoint, Roseville, CA, USA) for locating the bulb edge as a reference marker and further develop segmental-IMT (sIMT) which measures IMT in 10mm segments (namely: s1, s2 and s3) proximal to the bulb edge. MethodsThe patented methodology uses an integrated approach which combines carotid geometry and pixel-classification paradigms. The system first finds the bulb edge and then measures the sIMT proximal to the bulb edge. The system also estimates IMT in bulb region (bIMT). The 649 image database consists of varying plaque (light, moderate to heavy), image resolutions, shapes, sizes and ethnicity. ResultsOur results show that the IMT contributions in different carotid segments are as follows: bulb-IMT 34%, s1-IMT 29.46%, s2-IMT 11.48%, and s3-IMT 12.75%, respectively. We compare our automated results against reader's tracings demonstrating the following performance: mean lumen-intima error: 0.01235 0.01224mm, mean media-adventitia error: 0.020933 0.01539mm and mean IMT error: 0.01063 0.0031mm. Our system's Precision of Merit is: 98.23%, coefficient of correlation between automated and Reader's IMT is: 0.998 (p-value < 0.0001). These numbers are improved compared to previous publications by Suri's group which is automated multi-resolution conventional cIMT. ConclusionsOur fully automated bulb detection system reports 92.67% precision against ideal bulb edge locations as marked by the reader in the bulb transition zone.

The observed co-localization of disturbed flow and lesion prevalence at predisposed districts such as the carotid bifurcation has led to the identification of the wall shear stress (WSS) as biomechanical localizing factor of vascular dysfunction. In particular, a proatherogenic role is attributed to low and oscillatory WSS. However, the endothelial cells (ECs) are exposed to a complex hemodynamic milieu that can be only partially described by low/oscillatory WSS. Recently, in the attempt to close this gap, descriptors of the complex multidirectional nature of WSS have been proposed, i.e., the axial component of WSS (aligned with the vessel׳s centerline, to quantify flow reversal), and the transverse WSS (transWSS, quantifying the WSS component orthogonal to the cycle averaged WSS direction). Here we explore the relationship between recently-proposed indicators quantifying WSS multidirectionality and "established" WSS-based hemodynamic descriptors of low/oscillatory WSS, in a representative sample (N=46) of subject-specific computational hemodynamics models of ostensibly normal carotid bifurcations. To do it, we quantitatively assess the co-localization of those descriptors at the luminal surface, aiming at providing connections among the peculiar hemodynamic features captured by the different descriptors. According to our findings: (1) regions of flow reversal are moderately co-localized with low WSS; (2) high WSS oscillations (quantified by the oscillatory shear index, OSI) at the carotid bulb are prevalently aligned with the main flow, where flow reversal is predominant; (3) regions where transWSS is high do not co-localize with the other descriptors. We suggest that the investigated WSS-based descriptors might represent different hemodynamic disturbances with different impact on ECs homeostasis, potentially being part of WSS phenotypes more effective in localizing the map of vascular atherosclerotic lesions.

Purpose. To evaluate the repeatability and reproducibility of intima thickness (IT) measurements at different sites along the common carotid artery and compare with intima–media thickness (IMT) measurements. Methods. Ultrasound examinations of common carotid artery were performed in 30 healthy subjects and 20 patients with diabetes mellitus. Carotid IT and IMT were measured at 10 mm, 13 mm, and 16 mm upstream from the carotid bulb. Each subject was scanned by three operators to evaluate inter-operator reproducibility. Each operator scanned the subjects twice to evaluate intra-operator repeatability. Inter-equipment reproducibility of the measurements was evaluated. Results. The inter-operator reproducibility for measuring carotid IT at the three sites was 81.5%, 81.9% and 69.1%, respectively, slightly lower than carotid IMT measurement (89.7%, 86.5%, 75.2%, respectively). The intra-operator repeatability for carotid IT measurement at the three sites ranged 76.9–89.5%, 67.4–90.3%, and 55.2–70.5%, respectively, and was lower than for IMT measurement (86.5–96.9%, 87.6–95.7%, 79.9–86.5%, respectively). The inter-equipment reproducibility of IMT (75.7–86.6%) was slightly better than for IT measurement (71.4–75.9%). Conclusions. Ultrasonographic measurement of carotid IT is repeatable and reproducible, although not as good as IMT. Measurements preformed 10 mm to 13 mm upstream from the carotid bulb yield more repeatable and reproducible results. © 2011 Wiley Periodicals, Inc. J Clin Ultrasound 40:79–84, 2012

Anomalous origin of vertebral arteries is not common and usually seen as an incidental finding on imaging. We report a case of anomalous origin of left vertebral artery from left carotid bulb ("trifurcation" of left common carotid artery) on magnetic resonance angiography in a 64-year old male who also had ipsilateral thalamic acute infarct.

ventricular assist devices: A novel observation John T. Reul, George J. Reul, MD, and O.H. Frazier, MD From the Center for Cardiac Support, Texas Heart Institute at St. Luke’s Hospital, Houston, Texas; Division of Cardiovascular Surgery, Texas Heart Institute at St. Luke’s Hospital, Houston, Texas; and the Peripheral Vascular Laboratory, Texas Heart Institute at St. Luke’s Hospital, Houston, Texas

Black blood MRI is an attractive tool for monitoring normal and pathological wall thickening; however, limited spatial resolutions can conspire with complex vascular geometries to distort the appearance of the wall in ways hitherto unclear. To elucidate this, a thin-walled cylinder model was developed to predict the composite effects of obliqueness, in-plane resolution and voxel anisotropy on the accuracy of MRI-derived wall thickness measurements. These predictions were validated by means of imaging of a thin-walled carotid bifurcation phantom. Typical thick-slice axial acquisitions were found to result in artifactual wall thickening at the carotid bulb, owing to its obliqueness to the nominal imaging plane. Obliqueness was less problematic for near-isotropic resolutions; however, the obligatory reduction of in-plane resolution served to inflate wall thicknesses uniformly by up to 50%. Moreover, the nonlinear relationship between wall thickness and its overestimation served to mask genuine differences in wall thickness, an effect predicted to be worse for thinner coronary artery walls and plaque caps. Therefore, care must be taken when interpreting black blood MRI wall thickness measurements in the presence—or absence—of observed differences within or between individuals. Magn Reson Med 60:1020–1028, 2008. © 2008 Wiley-Liss, Inc.

The contribution of carotid baroreceptor feedback in preventing or potentially contributing to the essential hypertensive cascade is poorly understood. It is clear the carotid sinus nerve action potentials are triggered by carotid bulb stretch rather than pressure and are only sustained during pulsatile increases in pressure. In addition, the carotid baroreceptor negative feedback is gradually extinguished in hypertension patients (a phenomenon known as "resetting"). We report a case of significant reduction in blood pressure in a patient with true resistant hypertension after change in the carotid bulb pulsatile strain patterns following the implant of an intravascular prosthesis.

Various mechanical phenomena are thought to contribute to the pathogenesis of atherosclerosis. Most finite-element analyses of arterial-wall mechanics to date have focused on the quantification of mechanical wall stresses, despite an abundance of experimental evidence suggesting that endothelial and smooth muscle cells readily respond to cyclic strain. In this study, we calculate the physiologic cyclic strains in the carotid bifurcation, a common site of disease. Several geometries are constructed in this study, namely (i) a 3-D, but idealized geo- metry of the human carotid bifurcation, (ii) 3-D subject-specific geometries based on in vivo images of healthy volunteers' carotid bifurcations, and (iii) 2-D models based on histology-derived patient-specific anatomy and intra-plaque components. Results in both types of 3-D model show that the highest variations in cyclic strain are found at the adjoining wall of the external-common carotid and at the carotid apex, both frequent sites of early inflammation, as well as immediately distal to the carotid bulb, a site of late-stage disease, suggesting that cyclic strain may play a role in inflammation in that region as well. The 2-D models of diseased arteries show generally muted cyclic strain, but also regions such as in the shoulder regions of a fibrous cap adjacent to a lipid pool where cyclic strains are considerably elevated.

Purpose: This study was designed to determine whether there is a generalized trend of progressive enlargement of the common and internal carotid bulbs after carotid endarterectomy (CEA) reconstruction with saphenous vein patches. Methods: Twenty-nine autologous greater saphenous vein-patched CEAs performed between 1983 and 1994 were examined with five to nine sequential duplex scans each that included B-mode measurements of both the common carotid bulb (CCB) and internal carotid bulb (ICB) diameters. A total of 186 scans of each of the two segments were performed from 2 to 182 months after CEA (mean, 64 months). The time from the first to the last scan ranged from 30 to 120 months (mean, 76 months). Repeated measures analysis of variance was used as a means of testing the relationship of CCB and ICB diameters with time from CEA and with time from the first scan. Simple linear regression was used as a means of analyzing the variability of individual CCB and ICB diameters and pooled normalized diameters in both time frames. Results: The CCB diameters ranged from 8.4 to 18.5 mm (mean, 13.1 mm), and the ICB diameters ranged from 6.4 to 16.0 mm (mean, 11.2 mm). No significant relationship between both CCB and ICB diameters in the time from CEA or the time from the first scan ( P =.643 to.913), for sex ( P =.403 to.917), or for early and late post-CEA time of study onset ( P =.135 to.773) was shown by means of repeated measures analysis. Low R 2 values (CCB mean, 0.17; ICB mean, 0.21) and non-significant P values for regression slope (CCB mean, 0.46; ICB mean, 0.54) were given by means of individual regression analysis. There was no correlation between individual regression coefficients and the mean diameters of the arteries. The mean change in CCB diameter was 0.023 mm/year (range, –0.37 to 0.30 mm/year), and the mean change in ICB diameter was –0.030 mm/year (range, –0.33 to 0.37 mm/year). Regression of normalized CCB and ICB diameters versus time gave R 2 values less than 0.02 and slopes not statistically significantly different from zero. The predicted 10-year average percent change in normalized diameters ranged from 0.8% to 3.3%. Conclusion: In a 15-year period after CEA and a 10-year sequential B-mode scan study period, there was no evidence of significant enlargement of saphenous vein-patched CEAs. This is also true for CEAs in men and women and for subsets with larger and smaller CCB and ICB diameters and early and late scan onset times. Dilatation after saphenous vein patching is most likely a rare isolated event and not the result of generalized or frequent progressive enlargement. (J Vasc Surg 2002;35:131-6.)

Purpose: To compare postoperative morphological and rheological conditions after eversion carotid endarterectomy versus conventional carotid endarterectomy using computational fluid dynamics. Basic methods: Hemodynamic metrics (velocity, wall shear stress, time-averaged wall shear stress and temporal gradient wall shear stress) in the carotid arteries were simulated in one patient after conventional carotid endarterectomy and one patient after eversion carotid endarterectomy by computational fluid dynamics analysis based on patient specific data. Principal findings: Systolic peak of the eversion carotid endarterectomy model showed a gradually decreased pressure along the stream path, the conventional carotid endarterectomy model revealed high pressure (about 180 Pa) at the carotid bulb. Regions of low wall shear stress in the conventional carotid endarterectomy model were much larger than that in the eversion carotid endarterectomy model and with lower time-averaged wall shear stress values (conventional carotid endarterectomy: 0.03–5.46 Pa vs. eversion carotid endarterectomy: 0.12–5.22 Pa). Conclusions: Computational fluid dynamics after conventional carotid endarterectomy and eversion carotid endarterectomy disclosed differences in hemodynamic patterns. Larger studies are necessary to assess whether these differences are consistent and might explain different rates of restenosis in both techniques.