Multiplane reconstruction modifies the diagnostic performance of CT angiography in carotid webs

INTRODUCTION

Carotid Web (CaW) represents an overlooked stroke etiology and has been associated with high recurrence rates and to be amenable to stenting. We evaluated the diagnostic performance of different computed tomography angiography (CTA) projections in CaW.

METHODS

Consecutive patients <65 years-old with symptomatic CaW (n=31), carotid atherosclerosis (n=27), or normal carotids (n=49) diagnosed with a thin-cut CTA were included. Deidentified CTAs were independently reviewed by three readers, who recorded the diagnosis and level of certainty after evaluating the axial plane alone, after adding sagittal/coronal maximum intensity projection (MIP), then after oblique MPR reformats.

RESULTS

There were 93 total CaW, 81 atherosclerosis, and 147 normal carotid reads. With CTA axial projection alone, less CaW cases (44.1 %) were appropriately diagnosed as compared to atherosclerosis (87.7 %; p<0.001) and normal carotid (83 %; p<0.001) cases. Sagittal/coronal MIPS increased the rate of accurate CaW diagnosis (44.1-76.3 %; p<0.001). Inter-rater agreement in CaW detection increased from k= 0.46 (0.35-0.57) using axial to k= 0.80 (0.69-0.91) with sagittal/coronal planes. The axial projection alone had lower sensitivity (44 % vs. 76 %) but similar specificity (95 % vs. 96 %) in CaW detection compared to axial+ sagittal/coronal MIPS. The accuracy in detecting atherosclerosis or normal carotids did not increase after adding sagittal/coronal MIPS and oblique MPRs. The certainty level for CaW diagnosis was lower when compared to atherosclerosis and normal carotids using axial alone (3.0 [3.0-4.0] vs. 4.0 [3.0-5.0]; p<0.001 and 4.0 [3.0-5.0]; p<0.001) as well as after adding sagittal/coronal MIPS (4.0 [3.0-5.0] vs. 5.0[4.0-5.0]; p=0.01 and 4.0 [4.0-5.0]; p<0.001).

CONCLUSION

CTA axial plane alone was insufficient for CaW detection. CTA sagittal/coronal MIP reconstructions as well as oblique MPR reformats enhanced the accuracy and confidence related to CaW diagnosis.

In-hospital recurrent stroke in ipsilateral carotid web patients undergoing thrombectomy

OBJECTIVE

Carotid artery web is a possible cause of ischemic stroke, especially in young patients who lack conventional risk factors. The immediate and long-term outcomes are not well studied. We aimed to determine the association between an ipsilateral carotid web and in-hospital stroke recurrence.

METHODS

We analyzed data from adult patients admitted with an acute anterior circulation large vessel occlusion at a Comprehensive Stroke Center between July 2015 and March 2023. The primary outcome was in-hospital stroke recurrence and secondary outcome was in-hospital recurrent LVO. Multivariable logistic regression was performed to examine the association between ipsilateral carotid web and recurrent ischemic stroke and recurrent LVO.

RESULTS

Of the 1463 patients with anterior circulation large vessel occlusion, 27 (1.8%) had an ipsilateral carotid artery web. Patients with carotid web were younger (median age (IQR), 60 years (53-67 years) versus 74 years (62-84 years), P < 0.01) and less likely to be Caucasian (60% vs. 80%, p = 0.014). Of the 27 patients with carotid web, 18 (70%) had no identifiable competing stroke mechanism. When compared to patients without ipsilateral carotid web, those with an ipsilateral carotid web had a higher risk of recurrent ischemic stroke (adjusted RR: 4.38, 95% CI: 1.38-13.85) and recurrent ipsilateral large vessel occlusion (adjusted RR: 4.49, 95% CI: 1.41-14.21).

INTERPRETATION

Carotid webs are an under recognized cause of acute large vessel occlusion and are associated with higher risk of early recurrence. Studies are needed to validate our findings and test early revascularization strategies in patients with symptomatic carotid artery webs.

The differences between carotid web and carotid web with plaque: based on multimodal ultrasonic and clinical characteristics

OBJECTIVE

This study aimed to examine the clinical and multimodal ultrasonic characteristics differences between carotid web (CW) and CW with plaque as well as the potential risk factors for stroke caused by CW.

METHODS

We retrospectively enrolled patients diagnosed with CW by CTA or high-resolution MRI (HRMRI) and simultaneously underwent contrast enhanced ultrasound (CEUS) and superb microvascular imaging examinations from January 2015 to October 2022. The CW angle was measured using computer-aided software. The variations between CW and CW with plaque were evaluated, and univariable and multivariable logistic regressions were utilized to identify possible risk predictors for stroke caused by CW.

RESULTS

Two hundred ninety-nine patients with an average age of 60.85 (± 8.77) years were included. Sex, age, history of smoking, alcohol, hypertension, diabetes mellitus, homocysteine level, and treatment, as well as web length and thickness, luminal stenosis, location wall, number, CW angle, and CEUS enhancement, were quite different among CW and CW with plaque patients (p < 0.05). The logistic regression analysis showed that web length was an independent predictor of luminal stenosis in CW patients. For patients with CW and plaque, plaque and web thickness, as well as plaque enhancement, were associated with stenosis. Furthermore, luminal stenosis and plaque length were risk factors for symptoms.

CONCLUSION

The multimodal ultrasonic and clinical manifestations of CW and CW with plaque are quite different. Web length is an independent risk factor for carotid artery stenosis in CW patients, whereas luminal stenosis and plaque length were risk factors for symptoms in CW with plaque patients.

CRITICAL RELEVANCE STATEMENT

Exploring the similarities and differences between the carotid web and the carotid web with plaque, based on the stereo-geometric spatial position relationship and hemodynamic changes, may provide further insights into the underlying mechanisms of stroke occurrence caused by the carotid web.

KEY POINTS

1. Multimodal ultrasonic and clinical manifestations of carotid web and carotid web with plaque are substantially different. 2. A thin triangular endoluminal defect is identified as a typical feature of the web on superb microvascular imaging, and two kinds of typical ultrasonic features of CW with plaque are also identified. 3. Web length is an independent risk factor for carotid stenosis in carotid web patients, whereas luminal stenosis and plaque length are risk factors for symptoms in patients with CW and plaque.

Prevalence and clinical features of carotid artery web in patients undergoing endovascular thrombectomy for acute ischemic stroke

PURPOSE

Carotid artery web (CaW) is a rare focal fibromuscular dysplasia that can lead to embolic strokes with large vessel occlusion. This condition can be effectively treated with endovascular thrombectomy (EVT). Our study aims to assess the prevalence of CaW among patients with acute ischemic stroke (AIS) who underwent EVT and to compare the clinical characteristics of CaW with other carotid artery pathologies.

METHODS

We enrolled consecutive patients with AIS who underwent EVT at a single medical center and two regional teaching hospitals in Taiwan from September 2014 to December 2021. We compared CaW with carotid dissection (CaD) and carotid large artery atherosclerosis (CaLAA) in terms of patient demographics and thrombus histological findings.

RESULTS

Of the 576 AIS patients who underwent EVT, four (mean age: 50 years) were diagnosed with CaW, resulting in a prevalence of 0.69%. Among these four patients, three experienced successful reperfusion after EVT and achieved functional independence (defined as a modified Rankin Scale score ≤2) three months post-stroke. Importantly, none of the CaW patients suffered a recurrent stroke within one year. Patients with CaW were younger than those with CaD or CaLAA, and exhibited fewer vascular risk factors. Additionally, CaW was associated with distal occlusion sites. The thrombus composition in CaW patients was similar to that in CaD patients.

CONCLUSIONS

In conclusion, CaW is a rare finding among Asian patients with carotid artery disease who undergo for AIS. It is more prevalent in younger patients with a limited number of vascular risk factors.

Clinical, imaging, and management features of symptomatic carotid web: Insight from CAROWEB registry

BACKGROUND

Although carotid web (CaW) is increasingly diagnosed as a cause of cryptogenic stroke, data are still limited to monocentric small sample cohort. To broaden knowledge on symptomatic CaW, CAROWEB registry has been recently implemented.

AIMS

In a large cohort of symptomatic CaW patients, we described epidemiologic characteristics, admission clinical and imaging features, and the current management including the secondary preventive strategy choice made in comprehensive French Stroke Units.

METHODS

CAROWEB is an ongoing French observational multicenter registry enrolling consecutive CaW patients diagnosed after an ipsilateral ischemic stroke (IS) or transient ischemic attack (TIA). Submitted cases were validated by two experienced neurologist and neuroradiologist. Clinical, imaging, and management features were collected for this study.

RESULTS

Between June 2019 and December 2021, 244 cases were submitted by 14 centers, 42 rejected, and 202 included (IS, 91.6%; TIA, 7.9%; retinal infarction, 0.5%; mean age, 50.8 ± 12.2 years; female, 62.9%; Caucasian, 47.5%; Afro-Caribbean, 20.3%). IS patients showed median (interquartile range (IQR)) admission National Institutes of Health Stroke Scale (NIHSS) score, 8 (2-15); intracranial artery occlusion, 71.8%; ipsilateral chronic cerebral infarction (CCI), 16.3%; and reperfusion treatment, 57.3%. CaW was not identified during the mechanical thrombectomy procedure in 30 of 85 (35.3%) patients. Secondary prevention was invasive in 55.6% (stenting, n = 80; surgery, n = 30). In multivariable analysis, the invasive therapeutic option was associated with ipsilateral CCI (odds ratio (OR): 4.24 (1.27-14.2), p = 0.019) and inversely associated with risk factors (OR: 0.47 (0.24-0.91), p = 0.025) and admission NIHSS score (OR: 0.93 (0.89-0.97), p = 0.001).

CONCLUSION

CaW must be considered in all ethnic groups including Caucasians. Secondary prevention is heterogeneous in large French Stroke Centers. The absence of risk factors, milder severity strokes, and ipsilateral CCI were predictive variables of secondary invasive treatment. The high rate of invasive treatment suggests that medical treatment alone is deemed ineffective to avoid recurrence and emphasize the need of randomized trials.

Carotid webs: a review of pathophysiology, diagnostic findings, and treatment options

A carotid web (CaW) is an atypical form of fibromuscular dysplasia characterized by a fibrous, shelf-like intimal flap originating from the posterior wall of the internal carotid bulb projecting into the arterial lumen. CaWs disturb normal blood flow and create stasis between the intimal reflection and the carotid wall, thereby promoting thrombogenesis and increasing the risk of downstream embolic strokes. Observational data have suggested that CaWs are associated with strokes with otherwise unknown etiology, particularly in young patients without other stroke factors, and stroke recurrence rates of symptomatic CaWs have been reported to be as high as 20% over 2 years. Despite its clinical importance, there are currently no clear guidelines on the management of CaWs. In this narrative review, we discuss the epidemiology, pathogenesis, pathophysiology, diagnosis, and treatment options for this under-recognized entity.

Transient ischemic attack and minor stroke as "surgeons affairs": a narrative review

OBJECTIVE

The scope of this paper is to review the subtypes of transient ischemic attack (TIA) and minor stroke (mS) in which a surgical treatment is needed, discussing the importance and the timing of a multidisciplinary approach, in order to achieve an optimized management and prevent major strokes or other critical complications.

MATERIALS AND METHODS

The keywords "transient ischemic attack," "minor stroke," "surgical treatment," "vascular surgery," "heart surgery," "neurosurgery," and "multidisciplinary" were searched using MEDLINE, EMBASE, and Scopus. Relevant search results were discussed by the authors for references inclusion.

RESULTS

Notwithstanding that best medical therapy is usually the first choice for the most part of cases, there are specific but recurrent etiologies that must be properly recognized because of a potential surgical approach, even in urgency. In fact, symptomatic carotid stenosis, or particular cases of hemodynamic cerebrovascular events, should be promptly referred to vascular surgeon, since increasing evidences highlighted a benefit from an early artery revascularization. In addition, beyond arrhythmic causes, cardioembolic events due to bacterial endocarditis and atrial myxoma should be quickly diagnosed, possibly in emergency department, because they are a presumptive urgency for heart surgery. In addition to the above-mentioned conditions, in patients suffering from vertebrobasilar TIA or mS, clinicians should keep in mind the Bow Hunter disease, because surgical artery decompression can represent the only suitable treatment in selected cases.

CONCLUSIONS

TIA and mS require a multidisciplinary in order to discuss therapeutic options, comparing risks and benefits and determining the best timing for an optimized management.

Diagnosis and management of tandem occlusion in acute ischemic stroke

Approximately 20-30% of patients with acute ischemic stroke, caused by large intracranial vessel occlusion, have a tandem lesion, defined as simultaneous presence of high-grade stenosis or occlusion of the cervical internal carotid artery and thromboembolic occlusion of the intracranial terminal internal carotid artery or its branches, usually the middle cerebral artery. Patients with tandem lesions have usually worse outcomes than patients with single intracranial occlusions, and intravenous thrombolysis is less effective in these patients. Although endovascular thrombectomy is currently a cornerstone therapy in the management of acute ischemic stroke due to large vessel occlusion, the optimal management of extracranial carotid lesions in tandem occlusion remains controversial. Acute placement of a stent in the cervical carotid artery lesion is the most used therapeutic strategy compared with stented balloon angioplasty and thrombectomy alone without carotid artery revascularization; however, treatment strategies in these patients are often more complex than with single occlusion, so treatment decisions can change based on clinical and technical considerations. The aim of this review is to analyze the results of different studies and trials, investigating the periprocedural neurointerventional management of patients with tandem lesions and the safety, efficacy of the different technical strategies available as well as their impact on the clinical outcome in these patients, to strengthen current recommendations and thus optimize patient care.

Is carotid web an arterial wall dysplasia? A histological series

INTRODUCTION

Described for 60 years under various names, the carotid web is a suspected cause of cryptogenic stroke, especially in young patients. The web creates an intraluminal protrusion that may contribute to turbulent flow and thrombus embolization into cerebral arteries. Although the carotid web has frequently been related to arterial fibrodysplasia, its natural history and pathological description remain unclear.

PATIENTS

Among all consecutive patients admitted to the stroke unit of Sainte-Anne Hospital and referred to the vascular surgery department from January 2015 to December 2022, we retrospectively identified 9 patients with a carotid web. The surgical specimens of the 9 patients were submitted to systematic pathological analysis.

RESULTS

The patients with a histologically confirmed carotid web were young (median age was 42 years), prominently women (7/9), and presenting with low cardiovascular risk. Eight patients had a stroke proven by a magnetic resonance imaging, and 1 had transient monocular amaurosis. The typical pathological lesion supporting the imaging pattern of the carotid web was a focal eccentric intimal hyperplasia forming a protruding lesion characterized by a population of vascular smooth muscle cells intermingled in an abundant, most often loose extracellular matrix. Pathologically proven thrombus was observed in 4 cases. Importantly atherosclerosis was absent.

CONCLUSION

Histological features in our 9 cases strengthen carotid web characterization as a homogeneous pattern of localized intimal hyperplasia. It is a unique entity consistent with intimal fibroplasia, distinct from medial fibromuscular dysplasia and early atherosclerosis.

New asymptomatic thrombosis caused by carotid web during the acute period of cerebral infarction

BACKGROUND

At present, the carotid web (CaW) as an important cause of cryptogenic ischemic stroke has gradually received clinical attention. CaW is associated with a high risk of stroke and patient is more likely to have recurrent stroke if the CaW is untreated. We report a patient who developed CaW related thrombosis during the acute period of cerebral infarction.

CASE PRESENTATION

A 49-year-old male patient with CaW in the left internal carotid artery was diagnosed by computed tomography angiography (CTA) and had two cerebral infarctions in two years. Within 72 h after thrombolysis for an acute cerebral infarction, acute thrombosis was identified between the web and the posterior wall of the carotid artery on carotid ultrasound. Emergent carotid endarterectomy (CEA) was performed to remove abnormal CaW structures and thrombosis to prevent stroke. The patient recovered well and was asymptomatic at 2 months follow-up.

CONCLUSION

Carotid web related thromboembolism is a rare cause of stroke. Carotid ultrasound plays an important role in the diagnosis of asymptomatic thrombosis caused by carotid web. Carotid endarterectomy is effective for stroke prevention in patient with carotid web related thrombosis.

Symptomatic atherosclerotic plaque accompanied by carotid web

Here, we describe a case of a 67-year-old man who was transferred to our hospital with complaints of sudden upper right limb weakness and ataxia. Scattered acute cerebral infarction was found in the watershed zone between the left anterior cerebral artery and the middle cerebral artery territories. A shelf-like structure at the origin of the left carotid artery and a vulnerable plaque distal to the lesion was found. Symptomatic atherosclerotic plaque with concomitant carotid web was diagnosed. Carotid endarterectomy resulted in good revascularization. Hemodynamic changes associated with vascular stenosis are involved in atherosclerosis. The current case is valuable and shows that carotid web can cause not only embolic infarction but also cerebral thrombosis due to atheroma formation in the carotid artery.

Cerebral infarction caused by coexisting elongated styloid process and carotid web

OBJECTIVE

Elongated styloid process (ESP) and carotid web are rare etiologies of ischemic stroke. We report a rare case of ESP concomitant with carotid web as the cause of recurrent stroke.

CASE PRESENTATION

A 59-year-old man was admitted to our hospital with recurrent numbness and weakness in the right upper extremity. The patient had a long-standing history of lightheadedness and left-side amaurosis with neck flexion. Magnetic resonance imaging (MRI) confirmed scattered infarctions in the left frontal and parietal lobes. After multi-modal imaging we determined that embolic cerebral infarction was most likely to be secondary to the carotid web. Moreover, ESP causes dynamic hypoperfusion during neck flexion. We believe that this is a good reason for dealing with both pathologies during the same surgery. Thus, carotid endarterectomy and styloid process resection were performed at the same time. The previous symptoms during the head position change did not recur, and the right hand weakness was resolved.

CONCLUSION

ESP and carotid web are unusual mechanisms of ischemic stroke. Early diagnosis and timely treatment are essential to prevent subsequent severe strokes.

The carotid web: Current research status and imaging features

The carotid web is commonly found in the carotid bulb or the beginning of the internal carotid artery. It presents as a thin layer of proliferative intimal tissue originating from the arterial wall and extending into the vessel lumen. A large body of research has proven that the carotid web is a risk factor for ischemic stroke. This review summarizes the current research status of the carotid web and focuses on its imaging presentation.

Comparative analysis between 1-D, 2-D and 3-D carotid web quantification

BACKGROUND

Carotid webs (CaW) are now recognized as a cause of ischemic stroke in young patients. The thromboembolic potential appears related to the CaW's morphology and consequent impact on local flow dynamics. We aim to evaluate the reliability of different measurement methods for the quantification of CaW and their relationship to symptomatic status, presence of large vessel occlusion stroke (LVOS), clot burden and final infarct volume.

METHODS

This was a retrospective analysis of the local comprehensive stroke center CaW database (September 2014-July 2019). CT angiograms (CTAs) were reviewed independently by two raters, blinded to the clinical information and laterality of the stroke/transient ischemic attack. CaW were quantified with 1-D (length), 2-D (area) and 3-D (volume) measurements via Osirix software. Final infarct volume was calculated on MRI. Patients with superimposed CaW thrombus and no repeat imaging were excluded.

RESULTS

Forty-eight CaW (37 symptomatic and 11 contralateral/asymptomatic) in 38 patients were included. Mean age (±SD) was 48.7 (±8.5) years, 78.9% were women and 77.1% were black. Inter-rater agreement was 0.921 (p<0.001) for 1-D, 0.930 (p<0.001) for 2-D, and 0.937 (p<0.001) for 3-D CaW measurements. When comparing symptomatic with asymptomatic CaW, mean web length was 3.2 mm versus 2.5 mm (p<0.02), median area was 5.8 versus 5.0 mm² (p=0.35) and median volume was 15.0 versus 10.6 mm³ (p<0.04), respectively. CaW with a thinner profile (longer intraluminal projection compared with the base) were more likely to be symptomatic (0.67±0.17 vs 0.88±0.37; p=0.01). Average CaW 1-D and final infarct volume had a weak but positive association (Κ=0.230, p<0.05), while no association among web measurements and the presence of LVOS or clot burden was observed.

CONCLUSION

CaW dimension quantification (1-D, 2-D and 3-D) is highly reproducible. Linear and volumetric measurements were more strongly associated with symptoms. The impact of CaW size on the presence of LVOS, clot burden and final infarct volume is unclear.

Systematic review and meta-analysis of ipsilateral and contralateral carotid web prevalence in embolic supratentorial strokes of undetermined source

OBJECTIVES

A carotid web isdefined as an abnormal shelf-like projection of intimal fibrous tissue into the carotid bulb. Its presence may be an under-recognised source of embolic stroke of undetermined source (ESUS). The aim of this study was to investigate its prevalence in previously reported studies.

MATERIALS AND METHODS

A systematic literature review of Pubmed, EMBASE, and Scopus was conducted up until the 4/12/2021 using variations of the search terms - 'carotid web' and 'ischemic stroke'. Inclusion criteria were studies reporting carotid web prevalence in an ESUS cohort aged >18 years with adequate imaging. Secondary measures such as age, gender, ethnicity, and laterality were recorded. A meta-analysis of proportions was used to summarise the prevalence of webs along with a random-effects model to calculate the relative risk of ipsilateral and contralateral webs in ESUS.

RESULTS

The initial search yielded 361 articles, with 11 remaining post the inclusion and exclusion criteria. A meta-analysis of allage groups yielded a total carotid web prevalence among patients with stroke of unknown cause of 9.58 % (95 % CI 5.62 - 15.85). Carotid webs were more often detected in females (76.5 % ± 22.3 %), and in those of African heritage (58 % ± 39 %). In comparison with patients without an ischemic stroke, there was a significant association found for an ipsilateral carotid web (risk ratio of 2.74 (95 % CI: 2.14 - 3.51)) but no association found for contralateral webs (risk ratio of 1.50 (95 % CI: 0.94 - 2.40)).

CONCLUSION

The prevalence of ipsilateral carotid webs associated with ESUS is substantial, and may be more common in females and in individuals of African descent.

Dual-layer carotid stenting for symptomatic carotid web: Results from the Caroweb study

BACKGROUND & PURPOSE

Carotid Web (CaW) is a growingly recognized cause of ischemic stroke, associated with a high recurrence risk. Several therapeutic strategies have been proposed as a tertiary prevention including carotid stenting, endarterectomy and antithrombotic medications. Among these, carotid stenting with dual-layer stent may be promising to adequately cover the focal arterial dysplasia. Our aim was to investigate the safety and efficacy of the Casper stent in the treatment of symptomatic CaW.

METHODS

We conducted a retrospective analysis of consecutive patients presenting with a symptomatic CaW and included in the ongoing prospective observational multicenter CAROWEB registry. The study period was January 2015 to December 2021. Inclusion criteria were CaW treated with dual-layer Casper stent. Patients treated with other types of carotid stent, endarterectomy or antithrombotic medication were excluded. Clinical and radiological initial data and outcomes were recorded.

RESULTS

twenty-seven patients (with 28 caw) were included. median age was 52 (iqr: 46-68). median delay between index cerebrovascular event and cervical stenting was 9 days (IQR: 6-101). In all cases, the cervical carotid stenting was successfully performed. No major perioperative complication was recorded. No recurrent stroke or transient ischemic attack was observed during a median follow-up time of 272 days (IQR: 114-635). Long-term imaging follow-up was available in 25/28 (89.3%) stented CaW with a median imaging follow-up of 183 days (IQR: 107-676; range: 90-1542). No in-stent occlusion or stenosis was detected.

CONCLUSION

In this study, carotid stenting with dual-layer Casper stent in the treatment of symptomatic CaW was effective regarding stroke recurrence prevention and safe, without procedural nor delayed detected adverse event. However, the optimal therapeutic approach of symptomatic CaW still needs to be explored through randomized trials.

Uncommon Female-Predominant Etiologies of Cryptogenic Stroke

The etiologies of cryptogenic stroke are complex and heterogeneous. A number of uncommon etiologies are not fully recognized, some of which predominantly affect females. Most of these etiologies are closely related to the hormonal level, reproductive factors, coagulation function, and medications of females. Moreover, once cryptogenic stroke is diagnosed, females tend to have worse outcomes. Therefore, prompt etiological recognition and treatment are crucial for good recovery. The aim of this article is to review advances in exploring uncommon female-predominant etiologies of cryptogenic stroke. These etiologies are categorized into arterial, cardiac, and venous sources. Arterial vasoconstrictive narrowing, intimal injury, and intimal developmental abnormality can cause brain ischemia or artery-to-artery cerebral embolism. Myocardial contraction dysfunction, cardiac wall injury, and developmental abnormality can induce intracardiac thrombosis and lead to cardiac embolism. In addition, cortical venous thrombosis and occult venous thromboembolism via intracardiac or extracardiac channels also account for cryptogenic stroke in females. Due to the lack of knowledge, in clinical practice, the above etiologies are seldom assessed. The low incidence rate of these etiologies can lead to missed diagnosis. This review will provide novel clinical clues for the etiological diagnosis of cryptogenic stroke and will help to improve the management and secondary prevention of stroke in the female population. In the future, more studies are needed to explore the etiology and prevention strategies of cryptogenic stroke.

Carotid web: the challenging diagnosis of an under-recognized entity

BACKGROUND

Determining the cause of acute ischemic stroke is crucial for patient management, particularly for preventing future stroke. In recent years, carotid web (CW), a non-atherosclerotic disorder of the carotid wall, has been found to be an underestimated source of cerebral emboli.

OBJECTIVE

The present study aimed to analyze the clinical, radiological, and pathological findings, along with the treatments performed in patients with CW and ipsilateral ischemic events.

METHODS

Patients with anterior circulation ischemic stroke or transient ischemic attack and ipsilateral CW were prospectively included from January 2019 to December 2021.

RESULTS

Nine patients were enrolled. The median age was 55 (43-62) years, with a female-to-male ratio of 3.5:1. Of the total, seven patients (78%) consulted for recurrent ipsilateral ischemic events. Despite medical treatment, 44% of the patients experienced new episodes. Computed tomographic angiography was suggestive of CW in all cases in which it was performed. The interval between the first ischemic event and diagnosis of CW was of 13 (6-68) months. After ruling out any other possible etiology, every patient underwent carotid revascularization, one underwent stenting and eight underwent carotidectomy. No severe or long-term complications were noted. Histological studies confirmed the diagnosis of CW. There were no recurrences after carotid revascularization during a follow-up of 24 (13-35) months.

CONCLUSION

Knowledge of CW and differentiating it from atheroma plaques is essential, as medical management seems to be insufficient in many cases. Revascularization, which has been shown to be safe and effective, might be the best treatment modality.

Web Browsing: High-Speed Diagnosis and Treatment of Carotid Artery Web

Background: Although carotid artery web (CaW) was initially described in 1973 as a potential etiology of ischemic stroke, it still remains underrecognized. Because CaW is a membrane affixed perpendicularly from the carotid wall that projects out into the lumen above the bifurcation, it typically is not stenotic, and hence, utilizing only 1 vessel imaging modality during conventional stroke workup may instead lead to a diagnosis of ESUS: embolic stroke of undetermined source. The term ESUS was created in 2014 by researchers to define a subset of cryptogenic, nonlacunar (embolic-appearing) strokes without clear cardiac or vascular cause. Purpose: In this review, we describe how, after multiple evaluations of vessels, CaW was diagnosed in relatively young patients (age 39-47 years old, without significant vascular risk factors) in whom otherwise were considered embolic stroke of undetermined source. This observation dovetails with the accompanying  Neurohospitalist article entitled, “Delayed Thrombus Formation on Carotid Web and Its Medical and Endovascular Management for Secondary Stroke Prevention.” Research Design: Not applicable. Case review. Results/Conclusion: This report demonstrates the futility of antiplatelet therapy for a young patient with CaW-related stroke. Based on these collective experiences and review of the literature, we postulate that: (1) multiple vascular imaging modalities during stroke workup may result in a CaW diagnosis instead of ESUS; (2) young stroke patients without traditional vascular risk factors are candidates for this “web browsing” of extended imaging of vessels; and (3) carotid artery stenting (CAS) or carotid endarterectomy (CEA) may be preferred as first-line over medical therapy alone (ie, antiplatelet or anticoagulation) because CEA/CAS addresses the stroke etiology, CaW, definitively.

The Value of Contrast-Enhanced Ultrasound in the Evaluation of Carotid Web

Objectives

The purpose of this study was to investigate whether contrast-enhanced ultrasound (CEUS) is more advantageous than conventional ultrasound in the diagnosis of carotid web (CaW) and to compare the clinical characteristics of patients in different age groups.

Methods

Seventeen patients admitted to the hospital from October 2019 to December 2021 were included in our study. Patients were initially diagnosed with CaW using digital subtraction angiography (DSA), and conventional ultrasound and CEUS were completed. Baseline patient data were analyzed and compared between the <60 years old CaW group and the ≥60 years old CaW group to explore the differences between the two groups. Then, comparing the accuracy of conventional ultrasound and CEUS.

Results

A total of 17 CaW patients participated in this study, including 4 female patients (23.5%) and 13 male patients (76.5%), with an average age of 59.41 (±10.86) years. There were 9 patients (52.9%) with left CaW and 8 patients (47.1%) with right CaW. Acute ischemic stroke (AIS) occurred in 14 patients (82.4%). Thrombosis occurred in five of 17 patients (29.4%). There was a significant statistical difference about the thrombosis between the <60 years old CaW group and the ≥60 years old CaW group [<60 years group: 0 (0%), ≥60 years group: 5 (62.5%), P = 0.005]. Seven patients (41.2%) received medical management, nine patients (52.9%) had carotid artery stenting (CAS), and one patient (5.9%) had carotid endarterectomy (CEA). None of the patients had recurrent stroke during the follow-up period. The diagnostic rate of CaW and thrombus by CEUS was higher than that by conventional ultrasound, and there was a significant statistical difference in the diagnosis of thrombus between CEUS and conventional ultrasound (χ2 = 4.286, P = 0.038).

Conclusions

CEUS may have a higher diagnostic accuracy for CaW with thrombosis, and it has a higher clinical application prospect.

Advances in Recurrent Stroke Prevention: Focus on Antithrombotic Therapies

The past decade has seen significant advances in stroke prevention. These advances include new antithrombotic agents, new options for dyslipidemia treatment, and novel techniques for surgical stroke prevention. In addition, there is greater recognition of the benefits of multifaceted interventions, including the role of physical activity and dietary modification. Despite these advances, the aging of the population and the high prevalence of key vascular risk factors pose challenges to reducing the burden of stroke. Using a cause-based framework, current approaches to prevention of cardioembolic, cryptogenic, atherosclerotic, and small vessel disease stroke are outlined in this paper. Special emphasis is given to recent trials of antithrombotic agents, including studies that have tested combination treatments and responses according to genetic factors.

Evolution of Extracranial Internal Carotid Artery Disease in Children With Sickle Cell Anemia

BACKGROUND

Cerebral arteriopathy in patients with sickle cell anemia mainly affects the intracranial anterior circulation. However, the extracranial internal carotid artery (eICA) can also be stenosed and responsible for ischemic lesions. In children with sickle cell anemia, we perform routine annual Doppler ultrasound assessment of the eICA and magnetic resonance imaging with 3-dimensional time-of-flight magnetic resonance angiography of the Willis circle and neck arteries in those with abnormal velocity. Our aim was to report the evolution of eICA stenoses from 2011 to the present as a function of therapy in a retrospective case-series study. We hypothesized that chronic transfusion (CTT) would be more effective than hydroxyurea and simple observation on the evolution of eICA stenosis.

METHODS

Eligibility criteria were a history of eICA velocity ≥160 cm/s with a minimum Doppler and magnetic resonance imaging follow-up of 1 year. eICAs were graded for stenosis according to NASCET (The North American Symptomatic Carotid Endarterectomy Trial). Magnetic resonance imaging was investigated for ischemic lesions. Treatment with hydroxyurea and CTT were obtained from the chart review.

RESULTS

Fifty-four patients were included. Eight patients had a stroke history. The median (range) follow-up was 4.7 years (1.1-9.2 years). On the first neck magnetic resonance angiography, stenosis was present in 48/54 (89%) patients. Kinking was found in 39/54 (72%) patients. On the last neck magnetic resonance angiography, the proportion of patients with eICA stenosis decreased to 39/54 (72%). ICA occlusion occurred in 5 patients despite CTT. Three patients had carotid webs without intracranial stenosis. The proportion of patients with improvement in stenosis score was 8% with no treatment intensification, 20% with hydroxyurea, and 48% with CTT (P=0.016). The mean (SD) change per year in stenosis score was 0.40 (0.60) without intensification, 0.20 (0.53) with hydroxyurea, and -0.18 (0.55) with CTT (P=0.006). Ischemic lesions were present initially in 46% of patients, and the incidence of progressive ischemic lesions was 2.5 events/100 patient-years. Cox regression analysis showed that the initial score for eICA stenosis was a significant predictive factor for the risk of new silent cerebral infarct events.

CONCLUSIONS

Our study reinforces the need to assess cervical arteries for better prevention of cerebral ischemia and encourage initiation of CTT in sickle cell anemia children with eICA stenosis.

Multimodality imaging of carotid web: A case report and literature review

Objectives

The carotid web is a compelling potential mechanism of cryptogenic stroke. It is easy for it to escape diagnosis or be misdiagnosed, since it rarely causes hemodynamic stenosis. Currently, there is a lack of consensus on the prevalence, etiology, imaging evaluation, and treatment strategy of carotid artery. We aimed to present the multimodal imaging of carotid web and comprehensively review the characteristics of carotid web.

Methods

A 38 year-old man with carotid web, who presented with acute left hemispheric syndrome, was not identified by computed tomography angiography and high-resolution magnetic resonance imaging in the initial report, but were identified in retrospect and then confirmed by digital subtraction angiography and histopathology. A literature review of carotid web was performed to identify prevalence, nature history, imaging tools, and optimal management of carotid web.

Results

80 reports including 681 patients with carotid web were identified. The prevalence of symptomatic carotid web was 1.2% in patients with transient ischemic attack/stroke, 6.4% in patients with cryptogenic ischemic stroke, 1.1% in patients with large vessel occlusion stroke, and 4.4% in patients who operated on for carotid stenosis. A total of 23.0% patients had bilateral carotid web. In most patients, carotid web was located on the posterior wall (87.3%) of the carotid artery (98.7%). The mean length was 3.3 mm and mean stenosis rate was 20.9%. A total of 31.6% percent patients had thrombus trapped in carotid web and 75.9% patients had large vessel occlusion. Computed tomography angiography and digital subtraction angiography were favorable tools to detect carotid web. There were rare periprocedural complications and no recurrent strokes in carotid revascularization patients.

Conclusions

carotid web is an under-recognized cause of ischemic stroke. It is easy to be missed or misdiagnosed. Carotid revascularization can effectively prevent recurrent stroke for patients with symptomatic carotid web. Clinicians should strength their learning and understanding of carotid web.

Carotid Web Phenotype Is Uncommonly Associated With Classic Fibromuscular Dysplasia: A Retrospective Observational Study

BACKGROUND AND PURPOSE

Carotid web (CaW) is an intimal form of fibromuscular dysplasia (FMD) involving the carotid bulb which has been increasingly recognized as a potential cause of recurrent ischemic strokes. It is overlooked as a separate entity and often dismissed if no coexistent signs of classic FMD changes are observed. We aim to evaluate the frequency of classic FMD in high-yield vascular territories in patients with symptomatic CaW.

METHODS

This was a retrospective analysis of a symptomatic CaW database of 2 comprehensive stroke centers (spanning September 2014-October 2020). The diagnosis of a CaW during a stroke workup was defined as the presence of a shelf-like linear filling defect in the posterior aspect of the carotid bulb on computed tomography angiography in patients with acute ischemic stroke or transient ischemic attack of undetermined cause after a thorough evaluation. Neck computed tomography angiography and renal conventional angiography images were independently evaluated by two readers blinded to the laterality and clinical details to inspect the presence of underlying classic FMD.

RESULTS

Sixty-six patients with CaW were identified. Median age was 51 years (interquartile range, 42-57), and 74% were women. All patients had neck computed tomography angiography (allowing for bilateral vertebral and carotid evaluation), whereas 47 patients had additional digital subtraction angiography (which evaluated 47 carotids ipsilateral to the stroke and 10 contralateral carotids). Internal carotid artery classic FMD changes were noted in only 6 out of 66 (9%) in the ipsilateral carotids. No contralateral carotid or vertebral artery classic FMD changes were observed. Renal artery catheter-based angiography was obtained in 16 patients/32 arteries and only 1 patient/2 renal arteries demonstrated classic FMD changes.

CONCLUSIONS

CaW phenotype is uncommonly associated with classic FMD changes. Coexistent classic FMD does not constitute a useful marker to corroborate or exclude CaW diagnosis.

Embolectomy of acute embolic stroke associated with ipsilateral carotid web: a case report and literature review

A carotid web is a thin intraluminal protrusion located in the posterolateral wall of the carotid bulb, which might be a risk factor for cryptogenic stroke. The mechanism of ischemic stroke caused by carotid web is still unclear, but it might be related to hemodynamic changes distal to the web, resulting in flow forces and remote embolization of fibrin-based clots. The diagnosis of a carotid web mainly depends on carotid artery imaging examinations. The main therapeutic strategies include medical treatment with oral antiplatelet agents and anticoagulants, and operative treatment, such as carotid endarterectomy and carotid artery stenting. Few cases of acute large-vessel occlusion undergoing mechanical thrombectomy in the setting of carotid web as the etiology have been reported. We report here a case of a 37-year-old woman who underwent stent retriever embolectomy after acute ischemic stroke. Carotid artery imaging examinations, including digital subtraction angiography and magnetic resonance imaging, and pathology showed that a carotid web was located at the proximal right internal carotid artery. We also discuss the clinical pathophysiological and imaging features, and the treatment of carotid web as described in the currently available literature.

Prevalence and site of predilection of carotid webs focusing on symptomatic and asymptomatic Japanese patients

OBJECTIVE

Carotid webs (CWs) have increasingly been recognized as a cause of recurrent ischemic stroke. However, the natural history and clinical course of CWs remain unclear. The authors aimed to clarify the prevalence, imaging features, and optimal treatment of CWs in a Japanese cohort study.

METHODS

A series of 444 consecutive Japanese patients who had undergone CTA of the head and neck between April 2011 and October 2016 was retrospectively reviewed. CW was diagnosed on CT angiograms as a membrane-like intraluminal filling defect along the posterior wall of the carotid bulb or the origin of the internal carotid artery (ICA) on oblique sagittal images and a corresponding thin septum on axial images.

RESULTS

Two patients with CWs were identified among 132 patients with suspected stroke. The prevalence of CWs among symptomatic patients with suspected stroke was 1.5%. The prevalence of asymptomatic CWs was 2.2% (7 of 312 cases). The CWs were located in the posterior wall of the carotid bulb in 7 patients and just distal to the ICA origin in 2 patients. There were no apparent differences in the location or lesion length between symptomatic and asymptomatic CWs. Four of the 7 asymptomatic CWs remained asymptomatic for at least 2 years of follow-up. Two patients with symptomatic CWs developed recurrent cerebral infarction and transient ischemic attack despite being on a regimen of oral antiplatelet agents, and carotid endarterectomy was performed as radical treatment. Patients with CWs were younger than controls (median age 55 vs 69 years, p = 0.003) and were less frequently male than controls (33% vs 72%, p = 0.025). CW cases showed significantly fewer common atherosclerosis risk factors than the control group (p < 0.05).

CONCLUSIONS

Although limited to CTA patients, this study reported on the prevalence and common site of CWs, focusing on symptomatic and asymptomatic Japanese patients. Extensive cross-sectional and prospective observational studies are warranted to elucidate the overall prevalence and natural history of CWs.

Fibromuscular Dysplasia/Carotid Web in Angio-CT Imaging: A Rare Cause of Ischemic Stroke

Background and Objectives: Carotid web (CaW) is an intimal variant of fibromuscular dysplasia and may constitute as one of rare causes of acute ischemic stroke (AIS). The objective of this study was to determine the prevalence of CaW in patients with AIS or transient ischemic attack (TIA) based on head/neck CT angiography (CTA) in a Polish cohort study. Materials and Methods: A retrospective study was performed by analyzing 1480 electronic clinical and imaging data regarding patients with AIS or TIA, hospitalized in the years 2018–2020 in the authors’ institution. The final sample consisted of 181 patients who underwent head/neck CTA; aged 67.81 ± 13.51 years (52% were women). All head/neck CTA studies were independently evaluated by two radiologists. The patient’s clinical condition was assessed with the National Institutes of Health Stroke Scale (NIHSS, 5.76 ± 4.05 and 2.88 ± 3.38 at admission and at discharge, respectively). Results: 27 patients were identified with CaW. The prevalence of CaW in the final sample (181 pts with good quality CTA) was 14.9%. In the CaW group, 89% patients had AIS, including 26% diagnosed with recurrent and 11% with cryptogenic strokes. There were no significant differences between the presence of CaW and gender, age, NIHSS score, recurrent or cryptogenic stroke. Conclusions: Our study demonstrated that CaW may be an underrecognized entity leading to cerebrovascular events. The diagnosis of CaW depends on a high level of awareness and a comprehensive analysis of the neuroimaging studies. Our findings support the hypothesis that it is worthwhile to perform CTA to determine the etiology of ischemic stroke, particularly if predicting factors were not identified.

Imaging and clinical features of cervical artery web: report of 41 cases and literature review

This study investigated the imaging and clinical features of cervical artery web to improve disease diagnosis. Imaging and clinical data of 41 patients with cervical artery web were retrospectively analyzed and summarized in the context of the literature. Of the 8653 patients who underwent carotid computed tomography angiography (CTA) in the past 3 years at our hospital, 41 (0.47%) were diagnosed with cervical artery web. Among the 41 patients, there were 38 web structures in typical position, including 26 web structures located in the internal carotid artery and 12 in the proximal bifurcation of the common carotid artery. And the other three web structures were located outside carotid artery, including two in the subclavian artery and one in the vertebral artery. There were 47 web structures in 41 cases of cervical artery web; 35/41 (85.3%) were unilateral and 6/41 (14.7%) were bilateral. Among 41 patients, there were 20 patients who had cerebral infarction, 14 who experienced transient ischemic attack, 3 patients with cerebral hemorrhage; and 4 with other manifestations. Cervical artery web showed typical imaging features in the carotid CTA. Cervical artery web was most common in the internal carotid artery and at the bifurcation of the common carotid artery. It was also occasionally found in other rare artery such as vertebral and subclavian artery. Based on the various locations of web structure, we think it is necessary to rename carotid web as cervical artery web. Most of the attachment sites of the web structures were located in the posterior wall of the lumen, followed by the lateral wall; sites on the anterior wall were rare. Cervical artery web may be an underappreciated risk factor for stroke. And hypertension can increase the incidence of ischemic stroke in patients with cervical artery web.

Ipsilateral internal carotid artery web and acute ischemic stroke: A cohort study, systematic review and meta-analysis

Introduction

The carotid web is a compelling potential mechanism of embolic ischemic stroke. In this study, we aim to determine the prevalence of ipsilateral carotid web in a cohort of ischemic stroke patients and to perform a systematic review and meta-analysis of similar cohorts.

Patients & methods

We performed a retrospective, observational, cohort study of acute ischemic stroke patients admitted to a comprehensive stroke center from June 2012 to September 2017. Carotid web was defined on computed tomography angiography (CTA) as a thin shelf of non-calcified tissue immediately distal to the carotid bifurcation. We described the prevalence of carotid artery webs in our cohort, then performed a systematic review and meta-analysis of similar cohorts in the published literature.

Results

We identified 1,435 potentially eligible patients of whom 879 met criteria for inclusion in our analysis. An ipsilateral carotid web was detected in 4 out of 879 (0.45%) patients, of which 4/4 (1.6%) were in 244 patients with cryptogenic stroke and 3/4 were in 66 (4.5%) patients <60 years old with cryptogenic stroke. Our systematic review yielded 3,192 patients. On meta-analysis, the pooled prevalence of ipsilateral carotid web in cryptogenic stroke patients <60 was 13% (95% CI: 7%-22%; I² = 66.1%). The relative risk (RR) of ipsilateral versus contralateral carotid web in all patients was 2.5 (95% CI 1.5–4.2, p = 0.0009) whereas in patients less than 60 with cryptogenic stroke it was 3.0 (95% CI 1.6–5.8, p = 0.0011).

Discussion

Carotid webs are more common in young patients with cryptogenic stroke than in other stroke subtypes. Future studies concerning the diagnosis and secondary prevention of stroke associated with carotid web should focus on this population.

Carotid Web Diagnosed by Ultrasound Carotid Duplex in a Patient With Ischemic Stroke

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.

Nonstenotic Carotid Plaques in Ischemic Stroke: Analysis of the STRATIS Registry

BACKGROUND AND PURPOSE

Few studies assess nonstenotic carotid plaques on CTA, and the causative role of these plaques in stroke is not entirely clear. We used CTA to determine the prevalence of nonstenotic carotid plaques (<50%), plaque features, and their association with ipsilateral strokes in patients with cardioembolic and cryptogenic strokes.

MATERIALS AND METHODS

Data were from the Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke (STRATIS) registry, a prospective, nonrandomized registry of patients undergoing thrombectomy with the Solitaire device. The prevalence of nonstenotic carotid plaques ipsilateral and contralateral to the stroke was compared in patients with cryptogenic and cardioembolic strokes. Plaque features were further compared within both subgroups between patients with and without ipsilateral stroke. Adjusted associations among nonstenotic carotid plaque, plaque characteristics, and ipsilateral stroke in both subgroups were determined with logistic regression.

RESULTS

Of the 946 patients in the data base, 226 patients with cardioembolic stroke (median age, 72 years) and 141 patients with cryptogenic stroke (median age, 69 years) were included in the analysis. The prevalence of nonstenotic carotid plaque in the cardioembolic and cryptogenic subgroups was 33/226 (14.6%) and 32/141 (22.7%), respectively. Bilateral nonstenotic carotid plaques were seen in 10/226 (4.4%) patients with cardioembolic and 13/141 (9.2%) with cryptogenic strokes. Nonstenotic carotid plaques were significantly associated with ipsilateral strokes in the cardioembolic stroke (adjusted OR = 1.91; 95% CI, 1.15-3.18) and the cryptogenic stroke (adjusted OR = 1.69; 95% CI, 1.05-2.73) groups. Plaque irregularity, hypodensity, and per-millimeter increase in plaque thickness were significantly associated with ipsilateral stroke in the cryptogenic subgroup.

CONCLUSIONS

Nonstenotic carotid plaques were significantly associated with ipsilateral stroke in cardioembolic and cryptogenic stroke groups, and there was an association of plaque irregularity and hypodense plaque with ipsilateral stroke in the cryptogenic group, suggesting these plaques could be a potential cause of stroke in these patient subgroups.

Turbulence Intensity as an Indicator for Ischemic Stroke in the Carotid Web

OBJECTIVE

Carotid web (CaW) is reported as one of the causes of cryptogenic strokes. However, its pathophysiology is not known, which makes clinicians debate CaW treatment. The current study presents the mechanism of ischemic stroke in CaW and finds a potential indicator for ischemic stroke in CaW.

METHODS

Computational fluid dynamics (CFD) was applied to computer-aided artificial human CaW models to investigate the correlation between stenosis rate and CaW angle. The CFD results were compared with stroke or symptomatic CaW including adequate reported images for anatomic analysis of the stenosis rate and CaW angle.

RESULTS

The CFD result of the CaW models shows that the velocity decreases and the turbulence generation of blood flow increases in the area under CaW (AuCaW). In AuCaW, turbulence intensity (TI) is high in the high stenosis rate and small angle conditions. Moreover, TI remained high in the AuCaW throughout the cardiac cycles. The analysis of 67 anatomic figures appeared in 36 articles merged with CFD results, and a CaW scoring system was introduced for clinicians to determine patients with CaW with a high risk of ischemic stroke.

CONCLUSIONS

This study is believed to be the first to apply TI to CaW. Because most ischemic strokes in CaW occurred at a high stenosis rate and small angle, TI may be used as a potential indicator of ischemic stroke in CaW. Furthermore, TI is easily used in the daily clinical field by applying CaW scores.

Endarterectomy for symptomatic internal carotid artery web

OBJECTIVE

The carotid web (CW) is an underrecognized source of cryptogenic, embolic stroke in patients younger than 55 years of age, with up to 37% of these patients found to have CW on angiography. Currently, there are little data detailing the best treatment practices to reduce the risk of recurrent stroke in these patients. The authors describe their institutional surgical experience with patients treated via carotid endarterectomy (CEA) for a symptomatic internal carotid artery web.

METHODS

A retrospective, observational cohort study was performed including all patients presenting to the authors' institution with CW. All patients who were screened underwent either carotid artery stenting (CAS) or CEA after presentation with ischemic stroke from January 2019 to February 2020. From this sample, patients with suggestive radiological features and pathologically confirmed CW who underwent CEA were identified. Patient demographics, medical histories, radiological images, surgical results, and clinical outcomes were collected and described using descriptive statistics.

RESULTS

A total of 45 patients with symptomatic carotid lesions were treated at the authors' institution during the time period. Twenty patients underwent CAS, 1 of them for a CW. Twenty-five patients were treated via CEA, and of these, 6 presented with ischemic strokes ipsilateral to CWs, including 3 patients who presented with recurrent strokes. The mean patient age was 55 ± 12.6 years and 5 of 6 were women. CT angiography or digital subtraction angiography demonstrated the presence of CWs ipsilateral to the stroke in all patients. All patients underwent resection of CWs using CEA. There were no permanent procedural complications and no patients had stroke recurrence following intervention at the latest follow-up (mean 6.1 ± 4 months). One patient developed mild tongue deviation most likely related to retraction, with complete recovery at follow-up.

CONCLUSIONS

CEA is a safe and feasible treatment for symptomatic carotid webs and should be considered a viable alternative to CAS in this patient population.

Assessment of Recurrent Stroke Risk in Patients With a Carotid Web

Importance

A carotid web (CW) is a shelf-like lesion along the posterior wall of the internal carotid artery bulb and an underrecognized cause of young stroke. Several studies suggest that patients with symptomatic CW have a high risk of recurrent stroke, but high-quality data are lacking.

Objective

To assess the 2-year risk of recurrent stroke in patients with a symptomatic CW.

Design, Setting, and Participants

A comparative cohort study used data from the MR CLEAN trial (from 2010-2014) and MR CLEAN Registry (from 2014-2017). Data were analyzed in September 2020. The MR CLEAN trial and MR CLEAN Registry were nationwide prospective multicenter studies on endovascular treatment (EVT) of large vessel occlusion (LVO) stroke in the Netherlands. Baseline data were from 3439 consecutive adult patients with anterior circulation LVO stroke and available computed tomography (CT)-angiography of the carotid bulb. Two neuroradiologists reevaluated CT-angiography images for presence or absence of CW and identified 30 patients with CW ipsilateral to the index stroke. For these 30 eligible CW participants, detailed follow-up data regarding stroke recurrence within 2 years were acquired. These 30 patients with CW ipsilateral to the index stroke were compared with 168 patients without CW who participated in the MR CLEAN extended follow-up trial and who were randomized to the EVT arm.

Main Outcomes and Measures

The primary outcome was recurrent stroke occurring within 2 years after the index stroke. Cox proportional hazards regression models were used to compare recurrent stroke rates within 2 years for patients with and without CW, adjusted for age and sex. The research question was formulated prior to data collection.

Results

Of 3439 patients with baseline CT-angiography assessed, the median age was 72 years (interquartile range, 61-80 years) and 1813 (53%) were men. Patients with CW were younger (median age, 57 [interquartile range, 46-66] years vs 66 [interquartile range, 56-77] years; P = .02 and more often women (22 of 30 [73%] vs 67 of 168 [40%]; P = .001) than patients without CW. Twenty-eight of 30 patients (93%) received medical management after the index stroke (23 with antiplatelet therapy and 5 with anticoagulant therapy). During 2 years of follow-up, 5 of 30 patients (17%) with CW had a recurrent stroke compared with 5 of 168 patients (3%) without CW (adjusted hazard ratio, 4.9; 95% CI, 1.4-18.1).

Conclusions and Relevance

In this study, 1 of 6 patients with a symptomatic CW had a recurrent stroke within 2 years, suggesting that medical management alone may not provide sufficient protection for patients with CW.

Carotid webs in large vessel occlusion stroke: Clinical, radiological and thrombus histopathological findings

BACKGROUND

Carotid webs are an under-recognized embolic source in patients with cryptogenic stroke. Limited resources currently exist to assist clinicians in stroke prevention for patients with symptomatic carotid webs (SCW). We aimed at analysing the clinical, radiological and procedural features of stroke patients with SCW undergoing endovascular thrombectomy (EVT), and to describe the histopathological composition of their occlusive thrombi.

METHODS

In a single-center observational study on consecutive patients with ischemic stroke treated by EVT, carotid web was defined symptomatic when it was ipsilateral to the ischemic lesion in a patient classified with stroke of otherwise undetermined etiology. Clinical, radiological and procedural data of patients with SCW were evaluated. Histopathological examination of the retrieved thrombi was performed.

RESULTS

Out of 1430 patients with large vessel occlusion stroke treated by EVT, 11(0.7%) were found to have a SCW. Patients with SCW had a median age of 47 years old (IQR 38-50), they were prevalently women (55%), mostly of African ethnicity (91%). Each of the 11 patients achieved successful angiographic reperfusion (mTICI 2b-3) after EVT. For secondary prevention, elective endovascular carotid stenting was performed in 5 (55%) patients, while 1 (9%) was treated by surgical endoarterectomy. Histological analysis of the retrieved thrombi performed in 4 patients showed a mixed composition with variable red blood cell content.

CONCLUSIONS

EVT is feasible in large vessel occlusion stroke related to SCW. Procedures of carotid revascularization appear to be feasible therapeutic options for secondary prevention. The histopathological analysis of cerebral thrombi may provide new insights on stroke pathogenesis in patients with SCW.

Stroke Recurrence in First-Ever Symptomatic Carotid Web: A Cohort Study

Background and Purpose

Carotid web (CaW) is an intimal variant of fibromuscular dysplasia responsible for ipsilateral cerebral ischemic events (CIE). Symptomatic CaW likely has a high risk of recurrent CIE, but no salient prospective data are available. We aimed to assess recurrence rate and its predictors after a first-ever CIE.

Methods

Consecutive Afro-Caribbean patients who had cryptogenic first-ever CIEs (ischemic stroke [IS] or transient ischemic attack [TIA]) associated with ipsilateral CaW were included in this multicenter observational cohort study. The follow-up (January 2008 to March 2019) focused on CIE recurrences. Kaplan-Meier method assessed rates of recurrences and Cox proportional hazards regression analyzed risk factors.

Results

Ninety-two patients (79 first-ever ISs and 13 TIAs; mean age±standard deviation, 49.8±9.9 years; 52 [56.5%] women) were included. During a mean follow-up of 50.5±29.6 months, 19 (20.7%) patients experienced recurrent ipsilateral CIEs (16 ISs and three TIAs). Of 23 patients receiving surgery/stenting treatment, no recurrence occurred after the intervention (median follow-up, 39.8 months [interquartile range, 27.6 to 72.4]). Under medical treatment alone, the annual recurrent CIE rate was 6.9%, and the cumulative rate was 4.4% at 30-day, 10.8% at 1-year, 19.8% at 2-year, 23.2% at 3-year, and 27.3% at 5-year. Presence of silent cerebral infarctions was the only independent risk factor of CIE recurrences (hazard ratio, 6.99; 95% confidence interval, 2.4 to 20.4; P=0.004).

Conclusions

Under medical treatment alone, symptomatic CaW was associated with a high rate of recurrence that reached 27.3% at 5-year. Surgery/stenting seems to be efficient, and randomized control trials are required to confirm the benefit of these interventions.

Prevalence of carotid web in a French cohort of cryptogenic stroke

BACKGROUND AND PURPOSE

Carotid webs (CaW) may be an under-recognized cause of anterior circulation cryptogenic ischemic stroke (ACIS). Prevalence is still unknown in European patients with ACIS.

OBJECTIVE

To evaluate the prevalence of CaW in ACIS and describe patients with CaW phenotype in a cohort of patients from a French stroke center.

METHODS

We conducted a retrospective monocentric cohort study from 01/01/2015 to 31/12/2019 (Montpellier University Hospital, France), in consecutive anterior ischemic stroke (AIS) patients ≤65 years old from a prospective stroke database. Using ASCOD phenotyping, ACIS patients were selected and cervical CTA were reviewed to find CaW.

RESULTS

Among 1053 consecutive AIS patients, 266 ACIS patients with CTA were included. Among patients included (mean age 50, women 58%), CaW was in the ipsilateral carotid (iCaW) in 21 patients: 7.9% (95%CI [4.6-11.1]), (mean age 51, 11 women, 16 Caucasian). iCaW were uncovered during study review of CTA in 6/21 (29%) patients. Comparison between patients with iCaW and those without iCaW showed no differences except that of a higher rate of intracranial large vessel occlusion (LVO) (62.4 vs 37.6%; p = 0.03). Patients with iCaW under conservative medical therapy had an annualized stroke recurrence rate (SRR) of 11.4% (95%CI [8.4-15.1].

CONCLUSIONS

iCaW was identified as a source of stroke in about 8% of a French population ≤65 years with ACIS. iCaW was associated with a higher rate of LVO and a high SRR under conservative medical therapy.

Baseline Characteristics of Patients with Symptomatic Carotid Webs: A Matched Case Control Study

BACKGROUND AND PURPOSE

The baseline characteristics of patients with symptomatic carotid web (CaW) are unclear. We investigate demographic and cerebrovascular risk factors in patients with this overlooked stroke etiology.

METHODS

We identified consecutive patients diagnosed with symptomatic CaW at a comprehensive stroke center from July 2014-December 2018. These patients were matched at a 1:4 ratio (based on age and NIHSS scores) to create a control group of acute ischemic stroke (AIS) patients with non-CaW etiologies from the local GetWithTheGuidelines stroke database.

RESULTS

Thirty patients with symptomatic CaW were compared to 120 AIS patients with non-CaW etiologies. Symptomatic CaW patients were more likely to be female (73.3 vs. 44.2%; p = 0.004) and black (86.7 vs. 64.2%; p = 0.02). Symptomatic CaWs patients had a fewer absolute number of modifiable cerebrovascular risk factors (1.7±1.1 vs. 2.5±1.2; p = 0.002), lower rates of hypertension (43.4 vs. 63.3%; p = 0.04), and a more favorable lipid profile with lower average LDL (89.5±30.3 vs. 111.2±43.7 mg/dL; p = 0.01) and higher average HDL (47.9±11.3 vs. 42.2±13.8 mg/dL; p = 0.01) as compared to strokes with non-CaW etiology. Symptomatic CaW patients were more likely to have a large vessel occlusion (80.0 vs. 51.7%; p = 0.005), despite similar e-ASPECTS between the groups (8.1±2.1 vs. 8.3±2.2; p = 0.30). On multivariable analysis, symptomatic CaW was an independent predictor of independence at discharge (OR 3.72; 95%CI 1.27-10.94).

CONCLUSION

A gender and racial predilection of symptomatic CaWs may exist as females and blacks were were found to be more likely affected. Symptomatic CaW patients have a more benign cerebrovascular risk factor profile corroborating the proposed mechanism of local stasis and thromboembolism. Despite presenting more commonly with LVO, symptomatic CaW was associated with good functional outcome, warranting further studies.

Extracranial Vascular Disease: Carotid Stenosis and Plaque Imaging

Carotid atherosclerosis is an important contributor to ischemic stroke. When imaging carotid atherosclerosis, it is essential to describe both the degree of luminal stenosis and specific plaque characteristics because both are risk factors for cerebrovascular ischemia. Carotid atherosclerosis can be accurately assessed using multiple imaging techniques, including ultrasonography, computed tomography angiography, and magnetic resonance angiography. By understanding the underlying histopathology, the specific plaque characteristics on each of these imaging modalities can be appreciated. This article briefly describes some of the most commonly encountered plaque features, including plaque calcification, intraplaque hemorrhage, lipid-rich necrotic core, and plaque ulceration.

Diagnostic Yield of Neck CT Angiography in Young Adults With Anterior Circulation Ischemic Stroke: A Community Based Study

Background and Purpose

Few community-based studies investigating young adult strokes exist. The aim of this study was to determine the diagnostic yield of head and neck CTA in evaluation of anterior circulation ischemic stroke in young adults.

Materials and Methods

This retrospective review is limited to patients between the ages of 18-50 presenting to the Mayo Clinic Rochester emergency department or referred from smaller institutions in adjacent counties. Patients with posterior circulation infarcts, amaurosis fugax, central retinal artery occlusion or transient ischemic attacks were excluded. The presence of carotid dissection, webs, plaque, or other high-risk lesions were recorded.

Results

A total of 136 patients met inclusion criteria. Mean degree of carotid stenosis ipsilateral to infarct was 14.1%, compared to 6.5% on the contralateral side (p = .006). Ipsilateral mean carotid wall thickness measured .79 mm, compared to contralateral thickness of .80 mm (p = .51). Ipsilateral low-density plaque was observed in 22 patients (16.2%), and 21 patients (15.4%) on the contralateral side (p = .87). Ipsilateral calcified plaque was observed in 37 patients (27.2%), and 29 patients (21.3%) on the contralateral side (p = .31). 20 (14.7%) ipsilateral dissections were noted, compared to 4 (2.9%) contralateral dissections (p = .001). 3 (2.2%) ipsilateral carotid webs were identified, compared to 0 contralateral webs (p = .25).

Conclusion

Carotid dissection was the most common cause of anterior circulation infarct identified on cervical CTA in this population. Carotid webs and atherosclerosis were not common findings.

Current progress in clinical, molecular, and genetic aspects of adult fibromuscular dysplasia

Fibromuscular dysplasia (FMD) is a non-atherosclerotic vascular disease that may involve medium-sized muscular arteries throughout the body. The majority of FMD patients are women. Although a variety of genetic, mechanical, and hormonal factors play a role in the pathogenesis of FMD, overall, its cause remains poorly understood. It is probable that the pathogenesis of FMD is linked to a combination of genetic and environmental factors. Extensive studies have correlated the arterial lesions of FMD to histopathological findings of arterial fibrosis, cellular hyperplasia, and distortion of the abnormal architecture of the arterial wall. More recently, the vascular phenotype of lesions associated with FMD has been expanded to include arterial aneurysms, dissections, and tortuosity. However, in the absence of a string of beads or focal stenosis, these lesions do not suffice to establish the diagnosis. While FMD most commonly involves renal and cerebrovascular arteries, involvement of most arteries throughout the body has been reported. Increasing evidence highlights that FMD is a systemic arterial disease and that subclinical alterations can be found in non-affected arterial segments. Recent significant progress in FMD-related research which has led to improved understandings of the disease's clinical manifestations, natural history, epidemiology, and genetics. Ongoing work continues to focus on FMD genetics and proteomics, physiological effects of FMD on cardiovascular structure and function, and novel imaging modalities and blood-based biomarkers that can be used to identify subclinical FMD. It is also hoped that the next decade will bring the development of multi-centred and potentially international clinical trials to provide comparative effectiveness data to inform the optimal management of patients with FMD.

Carotid web: an under-recognized and misdiagnosed ischemic stroke etiology

BACKGROUND

Carotid web (CaW) constitutes a possible cause of ischemic stroke, particularly large vessel occlusion syndromes. We aim to evaluate misdiagnosis rates and diagnosis trends for CaW.

METHODS

Based on CT angiography (CTA), we prospectively identified a cohort of patients with symptomatic CaW treated at two comprehensive stroke centers (CSC) from 2014 to 2020 to assess misdiagnosis. Official CTA reports from the CSCs and referring hospitals were then reviewed for mention of CaW. For diagnosis trends, we retrospectively analyzed a CSC electronic medical record, identifying patients with CaW mentioned in an official CTA report from 2011 to 2020.

RESULTS

For misdiagnosis, 56 patients with symptomatic CaW were identified in the CSCs; 16 (28%) had bilateral CaW, totaling 72 CaWs. Only one CaW (5.5%) was reported at referring facilities, from 14 patients/18 CaWs imaged with CTA. Conversely, 43 (69%) CaWs were reported from 49 patients/62 CaWs at the CSC (p<0.01). For diagnosis trends, from 2011 to 2020, 242 patients at a CSC accounted for 266 CTA reports mentioning CaW. The majority of these reports (n=206, 77%) were associated with stroke/transient ischemic attack (TIA) ICD-9/ICD-10 codes. The rate of CaW diagnosis adjusted per 1000 patients with stroke/TIA increased over time, 2015 being the most significant point of change ('joinpoint'; p=0.01). The analysis of CaW mentions normalized per 1000 CTA reports also showed increasing rates of diagnosis over time (joinpoint:2014; p<0.02).

CONCLUSION

CaW was predominantly identified in patients with strokes/TIAs rather than asymptomatic patients. CaW was commonly overlooked in facilities with lower levels of cerebrovascular certification. Recognition of CaW at a CSC has significantly increased over time, independent of overall imaging and stroke patient volume.

Carotid webs associated with ischemic stroke. Updated general review and research directions

Carotid web (CaW) is an intimal variant of fibromuscular dysplasia strongly associated with ipsilateral cerebral infarction. Although considered rare, it is a recent and increasing concern for physicians involved in stroke diagnosis and management. The present general review relies on a systematic literature analysis and aims to update readers on the latest knowledge in the field of symptomatic CaW (syCaW). CaW associated with ipsilateral cerebral infarction or transient ischemic attack has been identified in 189 patients. Ischemic strokes (IS) mostly occur in middle age (mean 46 years) and predominately in females (66%). The high frequency of African descendant patients among case reports and series (58%) suggests an ethnic susceptibility for CaW development. CaW features are characterised by a shelf-like intraluminal defect on contrast sagittal imaging, a linear defect that splits the lumen on axial section, a post-contrast stagnation rostral to the lesion and a frequent contralateral mirrored CaW (26.6%). An artery-to-artery embolism mechanism is widely accepted via CaW blood stasis, thrombus formation and clot fragmentation scattered by blood flow. Therefore, cerebral infarctions are often large related to a high proportion of proximal occlusion (62.5%). CaW confers a high rate of IS recurrence despite standard anti-platelet treatment that reaches 33.3% of patients prospectively followed with a median time to event of one year. Although no randomised therapeutic studies are available, surgery (n=39) or stenting (n=50) have been often proposed and seem to avoid recurrences. CaW clearly emerges as a cause of cryptogenic embolic stroke and should be systematically investigated in routine. A large number of points remain to be elucidated and CaW patients should be steadily included in registries and randomised therapeutic studies.

Carotid web: an occult mechanism of embolic stroke

The carotid web is a proposed stroke mechanism that may underlie cryptogenic stroke, particularly in younger patients without vascular risk factors. The web appears as a shelf-like projection into the lumen of the proximal cervical internal carotid artery without evidence of calcification. It is pathologically defined as intimal fibromuscular dysplasia. Altered haemodynamics distal to the web cause flow stagnation and remote embolisation of fibrin-based clots. It is best demonstrated and diagnosed on CT angiography (CTA) of the neck because of its ability to resolve calcium and create multiplanar reconstructions. Although they can be readily visualised on CTA, carotid webs may be missed or misinterpreted because they do not typically cause haemodynamically significant stenosis and can mimic arterial dissection, non-calcified atherosclerotic plaque and intraluminal thrombus. Options for management include antiplatelet therapy, carotid endarterectomy and carotid artery stenting. Modern management strategies for cryptogenic stroke include long-term cardiac monitoring, further investigation for structural cardiac disease and a diagnostic workup for arterial hypercoagulability, however, these strategies are not likely to capture the possibility of a carotid web. Carotid webs should be suspected in a young patient presenting with recurrent unihemispheric strokes particularly when conventional vascular risk factors are not present.

Detection of Carotid Webs by CT Angiography, High-Resolution MRI, and Ultrasound

BACKGROUND AND PURPOSE

We sought to examine carotid webs (intimal variant fibromuscular dysplasia) by studying their clinical features and imaging profiles.

METHODS

All patients (n = 893) of the Department of Neurology at Beijing Tiantan Hospital between January and December 2019 were retrospectively reviewed for computed tomography angiography (CTA), high-resolution magnetic resonance imaging (HRMRI), and Doppler ultrasound data. Carotid webs were identified by two experienced neuroimaging experts according to the characteristics of a thin intraluminal filling defect along the posterior wall of the carotid bulb on sagittal CTA and a septum structure in arteries on axial CTA.

RESULTS

We found eight carotid web patients by CTA and Doppler ultrasound. Four of eight (50%) carotid webs were observed in the bilateral carotid arteries and other four of eight (50%) were ipsilateral. The mean age of the 8 patients was 50.75 (range 38-65) years; two were in women. Six of 8 patients (75%) with carotid webs had acute ischemic stroke. Two-thirds of patients with ischemic stroke were treated with carotid revascularization. Doppler ultrasound indicated that the septum projected into the carotid arteries in all patients. Half of the carotid web patients underwent HRMRI, showing features consistent with CTA findings. The Cohen's kappa coefficient for interobserver agreement in diagnosing carotid webs was .76.

CONCLUSIONS

Doppler ultrasound combined with CTA and HRMRI is effective and reliable method to identifying carotid webs, which may be associated with stroke.

Carotid webs management in symptomatic patients

BACKGROUND

Atypical fibromuscular dysplasia (AFMD), also known as carotid web, is a rare underdiagnosed shelf-like fibrous tissue arising from the posterior carotid artery bulb that is a cause of cryptogenic stroke of the anterior cerebral vascularization. Despite the recurrence and severity of strokes caused by embolization associated with AFMD, there are no recommendations on the best strategy to manage single and bilateral lesions, which have unsatisfactory outcomes when treated with medical treatment exclusively.

METHODS

From January 2016 to April 2019, 365 patients were operated on for a carotid stenosis in our institution. This cohort included 11 patients (3%), with a median age of 41 years (range, 39-51 years), referred by a stroke unit, treated for a symptomatic (10 strokes and 1 recurrent transient ischemic attack) AFMD lesion. Preoperative workup revealed a contralateral similar lesion in 45% of patients (5/11), which all also underwent surgery during a subsequent hospitalization. The diagnosis was confirmed by histologic examination when open surgery was performed. The 30-day and 1-year outcomes were retrospectively reviewed.

RESULTS

Of the 16 AFMD lesions operated, 13 were treated by open surgery (2 by classic endarterectomy and 11 by internal carotid resection-anastomosis) and 3 by carotid artery stenting, respectively, with a mean delay of 85.5 days and 20.5 days after the latest stroke. There was one complication after stenting (external iliac rupture) that was treated by a covered stent, and no perioperative complications after open surgery. The follow-ups at 30 days and 1 year were uneventful for all patients, without any deaths or stroke recurrences.

CONCLUSIONS

Symptomatic AFMD is a rare cause of cryptogenic stroke. Bilateral lesions are frequent. Early intervention is associated with favorable perioperative and 1-year outcomes. Open surgery is the first-line therapeutic option in this young patient population.