Spontaneous asymptomatic common carotid artery dissection resembling a carotid web: illustrative case.

BACKGROUND: Carotid artery dissection is a common cause of ischemic stroke, predominantly affecting the internal carotid artery, with rare involvement of the common carotid artery (CCA). The limited literature makes diagnosis and management challenging, particularly in asymptomatic patients. In this report, the authors present a unique case of spontaneous, asymptomatic CCA dissection that resembled a carotid web, shedding light on its clinical spectrum and management. OBSERVATIONS: A 70-year-old man was diagnosed with an intimal flap in the left CCA. Although the findings resembled those of a carotid web, cerebral angiography confirmed the presence of an intimal flap and arterial wall irregularities indicative of vascular dissection. Endarterectomy successfully prevented the stroke, and the postoperative recovery was uneventful. Pathological examination confirmed the diagnosis of CCA dissection. LESSONS: Spontaneous CCA dissection, though rare, presents significant diagnostic and therapeutic challenges. Because of morphological similarities, differentiating the diagnosis from a carotid web can be difficult. Available treatment strategies include antiplatelet therapy and surgical intervention. In this case, endarterectomy was chosen to avoid antithrombic treatment in anticipation of further invasive treatments for other conditions. The successful outcome highlights the potential as a treatment option, emphasizing the need for an individualized approach to each patient. https://thejns.org/doi/10.3171/CASE24344.

De novo formation of a carotid web in an adult: A longitudinal observation.

BACKGROUND: Carotid web is a thin shelf-like fibrointimal membrane arising from the posterior or posterolateral wall of the carotid bulb. Webs cause stroke, especially in younger adults with high risk of recurrence. METHODS: To report the first case of de-novo formation of an asymptomatic carotid web and describe longitudinal clinical-angiographic follow-up. RESULTS: A previously healthy 50-year-old White female presented with acute vestibular syndrome. Brain MRI showed no brain infarction. An arch-to-vertex CT angiogram showed normal posterior circulation, however, the left internal carotid artery bulb had a thin shelf-like projection into the lumen arising from the posterior wall of the artery - an incidental carotid web. A CT angiogram performed seven years earlier showed normal carotid arteries. The three-year angiographic follow-up showed an unchanged angiographic appearance of the carotid web. The patient preferred staying on aspirin and suffered no retinal or cerebral ischemic event during the 5-year clinic follow-up. CONCLUSION: Our case suggests de novo (acquired) formation of a carotid web in an adult. This challenges the prevailing theory that carotid web is a congenital/developmental lesion.

A case of carotid web with rapid thrombus expansion following mechanical thrombectomy with pathological evaluation by carotid endarterectomy.

A 48-year-old man with no history of diagnosis with any abnormality was admitted to our hospital 43 min after onset of stroke. He had a right conjugate deviation and severe left hemiparesis, and his initial National Institutes of Health Stroke Scale (NIHSS) score was 13. Computed tomography (CT) of the head revealed no early ischemic changes, while CT angiography showed occlusion of the M1 proximal segment of the right middle cerebral artery. Intravenous thrombolysis was administered within 27 min of admission, and mechanical thrombectomy was performed. Effective reperfusion was achieved 55 min after puncture. Carotid web (CaW) at the root of the right internal carotid artery was suspected to be the source of the embolus. Carotid ultrasonography (CUS) on the following day revealed an oval-shaped structure of equal intensity rising from the far wall. The structure enlarged over time, despite the administration of an antiplatelet agent. In addition to thrombi, intramural hematoma and neoplastic lesions were considered in the differential diagnosis. Carotid endarterectomy was performed on day 6. Pathologically, a mixed thrombus was identified adhering to the CaW; however, no neoplastic changes were observed. There were no postoperative complications, and the patient was discharged without neurological deficits on day 14. The CaW has anatomical factors morphologically associated with a high risk of thrombus formation. Pathologically, the involvement of hydrodynamic factors was considered more significant than the influence of the CaW surface morphology. CUS is a useful tool for assessing thrombus morphology.

Treatment of symptomatic carotid webs.

OBJECTIVE: The present study aims to describe the clinical characteristics and treatment outcomes of patients with symptomatic carotid web treated at a single institution in South America. MATERIALS AND METHODS: Retrospective study of a single-center experience of patients with carotid webs surgically treated from September 2019 to September 2023. RESULTS: 10 patients had carotid webs, six (60%) were females. Median age was 54.5 years (range: 35-77 years). All patients were symptomatic. Diagnosis was made in 90% (n=9) of the patients with either computed tomography angiography or magnetic resonance alone. One (10%) patient underwent angiography for definite diagnosis. The median interval from the first neurological event to intervention was 90 months (range: 3 days- 108 months). Four (40%) patients underwent surgical treatment within one month from symptom onset and carotid web diagnosis, with a median of 3.5 days (range: 3-9 days). Six (60%) patients underwent delayed surgical treatment since the cause of the neurological event was uncertain, with a median of 54 months (range: 6 - 108 months). These six patients had recurrent neurological events. Three (30%) patients underwent carotid endarterectomies with polyurethane patch and three (30%) by eversion technique. Three (30%) patients underwent segmental resection and reanastomosis of the internal carotid artery. One underwent internal carotid artery plasty with saphenous vein. At a median follow-up of 30 months (range: 6-46 months), one patient persists with mild aphasia, another patient has severe aphasia and right hemiparesis, both as sequalae of their initial strokes, and another patient has suffered 3 non-ischemic episodes of brief transient right hemiparesis attributed to epileptic seizures. The other seven patients remain without new neurological events. CONCLUSION: Neurological events of carotid distribution deserve accurate imaging work up, keeping in mind the diagnosis of carotid web. Surgical treatment for carotid web seems effective for preventing recurrences; nevertheless, further studies are warranted to define the best management for these patients.

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.

Managing pregnancy-related stroke risk with known bilateral internal carotid artery webs.

Carotid webs are intraluminal shelf-like projections caused by thickening of the arterial tunica intima. Due to their projections forming a nidus for thrombus formation and subsequent embolus, they are considered to be a rare cause of ischaemic strokes. We report a case of a woman with a background of recurrent ischaemic strokes due to bilateral carotid webs who presented with a twin pregnancy. We use this case to discuss how her pregnancy-related stroke risk was subsequently medically managed.

Histopathological Examination of a Symptomatic Carotid Web: A Case Report.

Carotid webs cause ischemic stroke in young people and are associated with a high rate of stroke recurrence. Histopathological examination is crucial for clarifying the pathogenesis and mechanisms underlying the occurrence of carotid webs, although the mechanisms generally remain unclear. Here, we report a case of a symptomatic carotid web in a woman in her 50s who had a medical history of two ischemic strokes. She was diagnosed with a right carotid web and underwent carotid endarterectomy 18 days after the second stroke. Histopathological examination clearly revealed several phases of intimal hyperplasia. Furthermore, a thrombus attached to the carotid web showed invasion by fibroblasts and capillaries, and organization had begun. We presume that after the appearance of the carotid web, the thrombus formed by stagnant flow and became organized, causing the carotid web to grow and change in shape.

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.

Carotid stenting for symptomatic carotid artery web: Multicenter experience.

OBJECTIVE: Carotid artery webs are an underappreciated cause of recurrent ischemic stroke, and may represent a significant portion of cryptogenic stroke. Evidence-based guidelines for the management of symptomatic carotid webs do not exist. The goal of this study is to audit our local experience for patients with symptomatic carotid artery webs undergoing carotid stenting as a treatment option, along with describing the hypothesized dynamic physiology of carotid webs. METHODS: All patients undergoing stenting for symptomatic carotid artery web at two comprehensive regional stroke centers with high endovascular thrombectomy volume from January 1, 2012 to March 1, 2021 were included. The modified Rankin Scale (mRS) score was used to define functional outcome at 3 months after stenting. RESULTS: Fourteen consecutive patients with symptomatic carotid artery webs underwent stenting. Twelve patients were female (86%), with a median age of 54 (IQR, 48-64) years across all patients. Stroke was the qualifying event in 12 (86%) patients and TIA in 2. Eleven patients (11/14, 79%) achieved a mRS score of 0-2 at 90 days, 2 (14%) were mRS 3-5, and one patient was lost to follow-up. The median follow-up was 12 months (IQR, 10-12). There was no recurrent stroke or TIA like symptoms in any patients. CONCLUSIONS: Carotid stenting appears to be safe at preventing recurrent stroke/TIA with a median follow-up of 12 months in this retrospective multicenter observational study.

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.

Symptomatic carotid webs require aggressive intervention.

OBJECTIVE: Carotid web (CaWeb) is a rare form of fibromuscular dysplasia that can produce embolic stroke. Misdiagnosis of symptomatic CaWeb as "cryptogenic stroke" or "embolic stroke of unknown source" is common and can lead to recurrent, catastrophic neurologic events. Reports of CaWeb in the literature are scarce, and their natural history is poorly understood. Appropriate management remains controversial. METHODS: CaWeb was defined as a single, shelf-like, linear projection in the posterolateral carotid bulb causing a filling defect on computed tomography angiography (CTA) or cerebral angiography. Cases of symptomatic CaWeb at a single institution with a high-volume stroke center were identified through collaborative evaluation by vascular neurologists and vascular surgeons. RESULTS: Fifty-two patients with symptomatic CaWeb were identified during a 6-year period (2016-2022). Average age was 49 years (range, 29-73 years), 35 of 52 (67%) were African American, and 18 of 52 (35%) were African American women under age 50. Patients initially presented with stroke (47/52; 90%) or transient ischemic attack (5/52; 10%). Stenosis was <50% in 49 of 52 patients (94%) based on NASCET criteria, and 0 of 52 (0%) CaWebs were identified with carotid duplex. Definitive diagnosis was made by CTA examined in multiple planes or cerebral angiography examined in a lateral projection to adequately assess the posterolateral carotid bulb, where 52 of 52 (100%) of CaWebs were seen. Early in our institutional experience, 10 of 52 patients (19%) with symptomatic CaWeb were managed initially with dual antiplatelet and statin therapy or systemic anticoagulation; all suffered ipsilateral recurrent stroke at an average interval of 43 months (range, 1-89 months), and five were left with permanent deficits. Definitive treatment included carotid endarterectomy in 27 of 50 (56%) or carotid stenting in 23 of 50 (46%). Two strokes were irrecoverable, and intervention was deferred. Web-associated thrombus was observed in 20 of 50 (40%) on angiography or grossly upon carotid exploration. Average interval from initial stroke to intervention was 39 days. After an average follow-up of 38 months, there was no reported postintervention stroke or mortality. CONCLUSIONS: To our knowledge, this is the largest single-institution analysis of symptomatic CaWeb yet reported. Our series demonstrates that carotid duplex is inadequate for diagnosis, and that medical management is unacceptable for symptomatic CaWeb. Recurrent stroke occurred in all patients managed early in our experience with medical therapy alone. We have since adopted an aggressive interventional approach in cases of symptomatic CaWeb, with no postoperative stroke reported over an average follow-up of 38 months. In younger patients presenting with cryptogenic stroke, especially African American women, detailed review of lateral cerebral angiography or multi-planar, fine-cut CTA images is required to accurately rule out or diagnose CaWeb and avoid recurrent neurologic events.

Breakthrough of dual-phase CT angiography features of carotid web and its correlation with ischemic stroke.

PURPOSE: To investigate the diagnostic value of dual phase CT angiography (CTA) in carotid web and its correlation with ischemic stroke. METHODS: The imaging data of 726 patients with cervical CTA from January 2015 to November 2019 in Taizhou People's hospital were retrospectively and consecutively analyzed. A total of 16 patients with 23 carotid webs were obtained. The location, morphology and clinical data of 16 patients were observed. Carotid web was identified by two experienced radioimaging 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: In the arterial phase, 23 carotid webs in 16 patients showed membrane like separation in the lumen of the posterior wall of the carotid bulb, and one web extended into the internal and external carotid arteries in a "Y" shape. There were 9 males and 7 females. In venous phase, 16 carotid webs showed linear enhancement, and 15 sites showed delayed emptying of contrast medium at the lateral margin. Five patients were acute or chronic ischemic stroke. The kappa coefficient for interobserver agreement in diagnosing carotid web was 0.79. CONCLUSION: Dual-phase CTA is effective and reliable method to identifying carotid webs, which may be associated with ischemic stroke.

Use of Carotid Web Angioarchitecture for Stroke Risk Assessment.

OBJECTIVE: To examine the usefulness of carotid web (CW), carotid bifurcation and their combined angioarchitectural measurements in assessing stroke risk. METHODS: Anatomic data on the internal carotid artery (ICA), common carotid artery (CCA), and the CW were gathered as part of a retrospective study from symptomatic (stroke) and asymptomatic (nonstroke) patients with CW. We built a model of stroke risk using principal-component analysis, Firth regression trained with 5-fold cross-validation, and heuristic binary cutoffs based on the Minimal Description Length principle. RESULTS: The study included 22 patients, with a mean age of 55.9 ± 12.8 years; 72.9% were female. Eleven patients experienced an ischemic stroke. The first 2 principal components distinguished between patients with stroke and patients without stroke. The model showed that ICA-pouch tip angle (P = 0.036), CCA-pouch tip angle (P = 0.036), ICA web-pouch angle (P = 0.036), and CCA web-pouch angle (P = 0.036) are the most important features associated with stroke risk. Conversely, CCA and ICA anatomy (diameter and angle) were not found to be risk factors. CONCLUSIONS: This pilot study shows that using data from computed tomography angiography, carotid bifurcation, and CW angioarchitecture may be used to assess stroke risk, allowing physicians to tailor care for each patient according to risk stratification.

Management of a recurrent stroke due to a carotid web.

Carotid web is a rare intraluminal parietal protrusion in the carotid artery. This vascular anomaly mostly occurs at the bifurcation causing turbulent flow, and is responsible of thrombi formation associated with embolic ischemic events. We report the case of a 35-year-old woman, with no medical history, who presented a recurrent middle cerebral artery (MCA) occlusion within twelve hours caused by a carotid bulb web. Although considered as a rare entity, carotid web is associated with the risk of recurrent strokes in the MCA territory and especially in the absence of the typically recognized risk factors. The key imaging is the CT angiography that shows the web, the cerebral artery occlusion, and the outcome appreciation. Therapeutic strategy associates antithrombotic treatment and operative management with stenting of the carotid web or endarterectomy.

The case of treatment for carotid web - Double-layer micromesh stent implantation in our hospital.

Background: A carotid web is a shelf-like structure on the posterior wall of the origin of the internal carotid artery, and it is believed to cause cerebral infarction due to thrombus formed by turbulent flow with stagnation of blood flow. Recently, it has been suggested that recurrent cerebral infarction cannot be prevented in patients with a symptomatic carotid web by conventional medical management alone. However, there is still no consensus on the treatment of carotid webs. Carotid artery stenting (CAS) with the CASPER stent (Microvention, Terumo, Tustin, CA, USA) was performed in six consecutive patients with symptomatic carotid webs, and the results are reported along with a review of the literature. Methods: Six consecutive patients with a diagnosis of internal carotid artery stenosis due to a carotid web on magnetic resonance imaging and digital subtraction angiography (DSA) were included in this study. All patients underwent dual antiplatelet therapy approximately 10 days before surgery and after 6 months, and then, a CASPER stent was implanted under general anesthesia. All patients were evaluated postoperatively by DSA 6 months after treatment. Results: In all patients, no in-stent stenosis was seen 6 months after the operation, and no symptomatic cerebral infarction occurred within 1 year after the procedure. Conclusions: CASPER stent implantation may be effective for treating carotid webs.

Carotid web arising in the common carotid artery and adjacent to a transverse process of the cervical spine: A case report.

BACKGROUND AND IMPORTANCE: A carotid web (CaW) is an intraluminal membrane-like filling defect typically located in the posterior wall of the proximal internal carotid artery and is increasingly recognized as a potential cause of embolic stroke. We herein reported a case of a CaW that has an unusual location at the CCA; furthermore, an elongated transverse process of the cervical spine was adjacent to the CaW at the CCA. CLINICAL PRESENTATION: An 87-year-old woman with a history of minor stroke underwent thorough radiological examinations of her CCA lesion. Radiological examinations, including duplex ultrasonography, digital subtraction angiography (DSA), computed tomography, and magnetic resonance angiography, revealed that the morphological characteristics of the lesion were compatible with those of a typical CaW except for its location at the CCA. Furthermore, three-dimensional DSA revealed that the lesion was adjacent to the transverse process of the sixth cervical spine (C6), suggesting mechanical damage by the spinal transverse process as a possible pathogenesis of this CaW. CONCLUSION: This is the rare case of a CaW located in the CCA, far from the carotid bulb. Arterial dissection due to mechanical damage by the spinal transverse process may be a possible causative mechanism of the CaW in the present case.

Assessment of Complex Flow Patterns in Patients With Carotid Webs, Patients With Carotid Atherosclerosis, and Healthy Subjects Using 4D Flow MRI.

BACKGROUND: Carotid webs (CaWs) are fibromuscular projections in the internal carotid artery (ICA) that cause mild luminal narrowing (<50%), but may be causative in up to one-third of seemingly cryptogenic strokes. Understanding hemodynamic alterations caused by CaWs is imperative to assessing stroke risk. Time-Average Wall Shear Stress (TAWSS) and Oscillatory Shear Index (OSI) are hemodynamic parameters linked to vascular dysfunction and thrombosis. PURPOSE: To test the hypothesis: "CaWs are associated with lower TAWSS and higher OSI than mild atherosclerosis or healthy carotid bifurcation." STUDY TYPE: Prospective study. POPULATION: A total of 35 subjects (N = 14 bifurcations with CaW, 11F, age: 49 ± 10, 10 mild atherosclerosis 6F, age: 72 ± 9, 11 healthy 9F, age: 42 ± 13). FIELD STRENGTH/SEQUENCE: 4D flow/STAR-MATCH/3D TOF/3T MRI, CTA. ASSESSMENT: 4D Flow velocity data were analyzed in two ways: 1) 3D ROI in the ICA bulbar segment (complex flow patterns are expected) was used to quantify the regions with low TAWSS and high OSI. 2) 2D planes were placed perpendicular to the centerline of the carotid bifurcation for detailed analysis of TAWSS and OSI. STATISTICAL TESTS: Independent-samples Kruskal-Wallis-H test with 0.05 used for statistical significance. RESULTS: The percent surface area where low TAWSS was present in the ICA bulb was 12.3 ± 8.0% (95% CI: 7.6-16.9) in CaW subjects, 1.6 ± 1.9% (95% CI: 0.2-2.9) in atherosclerosis, and 8.5 ± 7.7% (95% CI: 3.6-13.4) in healthy subjects, all differences were statistically significant (ƞ2 = 0.3 [95% CI: 0.05-0.5], P-value CaW vs. healthy = 0.2). OSI had similar values in the CCA between groups (ƞ2 = 0.07 [95% CI: 0.0-0.2], P-value = 0.5), but OSI was significantly higher downstream of the bifurcation in CaW subjects compared to atherosclerosis and normal subjects. OSI returned to similar values between groups 1.5 diameters distal to the bifurcation (ƞ2 = 0.03 [95% CI: 0.0-0.2], P-value = 0.7). CONCLUSION: Lower TAWSS and higher OSI are present in the ICA bulb in patients with CaW when compared to patients with atherosclerotic or healthy subjects. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.

[A case of recurrent stroke with carotid-web despite dabigatran treatment successfully treated by carotid endarterectomy].

We present a case of a 41-year-old female presenting with recurrence of ischemic stroke on subtherapeutic doses of dabigatran. She had a history of embolic stroke of undetermined sources at the age of 40, and underwent implantable cardiac monitor implantation and had started dabigatran. One year after the first ischemic stroke, she presented with sudden dysarthria and left hemiparesis and was admitted to our hospital. An MRI of the head revealed acute cerebral infarction in the right corona radiata, and an MR angiography revealed right M2 occlusion. Cervical 3D-CTA revealed a protruding structure on the posterior wall of the carotid artery bulb, which was diagnosed as carotid web. She underwent carotid endarterectomy, and the specimen was pathologically confirmed to be vascular malformation due to fibromuscular dysplasia.

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.