Atypical Carotid Webs: An Elusive Etiology of Ischemic Stroke

OBJECTIVE

Typical carotid webs are nonatherosclerotic shelf-like projections of fibromyxoid tissue extending from the posterior wall of the proximal internal carotid artery. Carotid webs may precipitate acute embolic stroke, especially in younger patients. We describe our experience with pathology-proven carotid webs of atypical appearance, or atypical carotid webs (ACWs), a subset of carotid webs exhibiting abnormal location, morphology, or association with atherosclerotic changes.

METHODS

Our electronic medical record database was queried for all imaging impressions containing "carotid web," "shelf," or "protrusion" from 2018 to 2024. Imaging was reviewed by an experienced neuroradiologist and neurosurgeon. Patients with typical carotid webs or those with different diagnoses (e.g. dissection/thrombus) were excluded.

RESULTS

Twenty-seven patients were treated for typical carotid webs; 24 were treated with carotid endarterectomy (CEA) and had pathology-confirmed webs. Five patients (3 male) were identified to have ACWs and included in this report. The mean age was 43.6 years. All ACWs were identified by computed tomography angiography. All patients presented with acute ischemic stroke or transient ischemic attack. One web was located on the anterior internal carotid artery wall, 3 were of abnormal morphology different from a "shelf-like" projection, and one was associated with atherosclerotic change. No patients experienced a further stroke or transient ischemic attack following CEA.

CONCLUSIONS

ACWs may precipitate ischemic stroke and can be treated and definitively diagnosed with CEA. Due to their unusual appearance, ACWs may evade radiographic identification or be misdiagnosed. As ACWs have not been previously reported in the literature, awareness of their existence must be raised to increase their detection and treatment.

Carotid web catheter angiography hemodynamic parameters

BACKGROUND

Carotid web (CaW)-related contrast stagnation on digital subtraction angiography (DSA) may be a marker supporting the pathophysiological theory of stasis and thrombosis/embolization. We aim to assess the correlation between DSA hemodynamic parameters with CT angiography (CTA) structural measurements and clinical characteristics.

METHODS

Cross-sectional analysis of consecutive patients with CaW who underwent CTA+DSA. DSA-derived hemodynamic parameters were calculated based on a region of interest at the carotid bulb (time-density curves; TDC). The correlation between duration of contrast stagnation with CaW structural features and with clinical characteristics was evaluated with a mixed effects model.

RESULTS

Sixty patients of mean±SD age 52.2±10.3 years were included, of whom 38 (63.3%) were women, 51 (85%) were black, and 59 (98.3%) had symptomatic lesions. The median CaW base was 2.46 mm (range 1.95-3.76), length 2.7 mm (range 2.15-3.96), thickness (length/base) 1.05 (IQR 0.81-1.36), caudal angle 31.93° (IQR 22.35-43.58), mean±SD distal angle 66.91±15.84°, pocket area 1.62 mm² (0.96-1.62), and pocket perimeter 6.03±2.6 mm. The TDC consistently showed an initial fast decay from the peak concentration followed by a plateau with a negative exponential pattern. The median stagnation time from peak density to 80% contrast clearance was 2.91 s (range 1.81-4.94). No significant associations were observed between the stagnation time and CaW CTA structural measurements (length/base/thickness, caudal and cranial angles web surface angles, web pocket area/perimeter) or clinical characteristics.

CONCLUSIONS

A negative exponential pattern in the DSA contrast clearance of the CaW pocket was observed. There were no morphological or clinical features clearly associated with the duration of contrast stagnation on DSA. The hemodynamic disruption caused by CaW and its thrombotic risk may not be appropriately measured by contrast stagnation time.

Two-stage convolutional neural network for segmentation and detection of carotid web on CT angiography

BACKGROUND

Carotid web (CaW) is a risk factor for ischemic stroke, mainly in young patients with stroke of undetermined etiology. Its detection is challenging, especially among non-experienced physicians.

METHODS

We included patients with CaW from six international trials and registries of patients with acute ischemic stroke. Identification and manual segmentations of CaW were performed by three trained radiologists. We designed a two-stage segmentation strategy based on a convolutional neural network (CNN). At the first stage, the two carotid arteries were segmented using a U-shaped CNN. At the second stage, the segmentation of the CaW was first confined to the vicinity of the carotid arteries. Then, the carotid bifurcation region was localized by the proposed carotid bifurcation localization algorithm followed by another U-shaped CNN. A volume threshold based on the derived CaW manual segmentation statistics was then used to determine whether or not CaW was present.

RESULTS

We included 58 patients (median (IQR) age 59 (50-75) years, 60% women). The Dice similarity coefficient and 95th percentile Hausdorff distance between manually segmented CaW and the algorithm segmented CaW were 63.20±19.03% and 1.19±0.9 mm, respectively. Using a volume threshold of 5 mm3, binary classification detection metrics for CaW on a single artery were as follows: accuracy: 92.2% (95% CI 87.93% to 96.55%), precision: 94.83% (95% CI 88.68% to 100.00%), sensitivity: 90.16% (95% CI 82.16% to 96.97%), specificity: 94.55% (95% CI 88.0% to 100.0%), F1 measure: 0.9244 (95% CI 0.8679 to 0.9692), area under the curve: 0.9235 (95%CI 0.8726 to 0.9688).

CONCLUSIONS

The proposed two-stage method enables reliable segmentation and detection of CaW from head and neck CT angiography.

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.

CONCLUSION

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 Insights on My Acute Ischemic Stroke Caused by a Carotid Web

Acute ischemic stroke, a medical emergency caused by reduced cerebral blood flow, results in brain cell damage. While commonly associated with older individuals, strokes can also occur in young and middle-aged adults, posing significant socio-economic and health challenges due to the long-term impact of the condition. This poses significant socio-economic and health challenges because stroke is a leading cause of disability and mortality. A carotid web (CaW), a rare form of fibromuscular dysplasia, is increasingly recognized as a cause of cryptogenic stroke in young adults. Characterized by a fibrous intimal flap in the internal carotid artery, a CaW disrupts blood flow, promoting thrombosis and increasing stroke risk. I am a 46-year-old pediatrician with no significant medical history who experienced an ischemic stroke due to a CaW. The onset occurred during a morning jog when I experienced nausea, malaise, and unsteady movement. Although I exhibited no headache or paralysis, my wife observed slurred speech, prompting emergency consultation three hours after onset. Imaging revealed ischemia in the left middle cerebral artery territory. I underwent thrombolysis and mechanical thrombectomy, with good recovery except for mild aphasia. Pathological examination confirmed a CaW in the left carotid artery, with myxoid intimal changes and fibroblast proliferation. While the initial ultrasound (US) failed to detect a CaW, subsequent detailed US identified the lesion. Routine magnetic resonance angiography (MRA) also missed the CaW, highlighting its limitations in detecting such abnormalities. Diagnostic modalities like digital subtraction angiography (DSA) and computed tomography angiography (CTA) are effective but invasive. Non-invasive alternatives, such as US and MRA, are limited by operator dependency and technical constraints. For instance, B-mode US in experienced hands can detect CaWs in longitudinal views, but its diagnostic accuracy is lower than that of CTA and DSA. Advanced imaging, such as contrast-enhanced US and 3D MRA, offers potential improvements but is not yet standard practice. In my case, CTA provided a definitive diagnosis, while initial US and MRA missed smaller lesions. My recovery included intensive rehabilitation to address residual aphasia. Although I resumed professional duties within three months, minor symptoms, such as mild numbness and occasional speech difficulty, persist. This case highlights the diagnostic challenges of CaWs, particularly pre-stroke. Further research is needed to improve non-invasive detection methods and understand the pathogenesis of CaWs in order to facilitate earlier diagnosis and prevention.

Short-term recurrence of stroke following misdiagnosis of carotid web masked by thrombus

Background

Carotid webs are a potential cause of occult cerebral infarction. Although they occur frequently, proper diagnosis and treatment are crucial; surgery has been shown to provide a good outcome. Although thrombus on the carotid web have been reported, digital subtraction angiography (DSA)-confirmed cases of pre-dispersed thrombus are rare. In this study, we report a case in which a thrombus on the carotid web concealed a shelf-like defect, complicating its diagnosis.

Case Description

A 47-year-old woman without stroke risk factors presented to our hospital with aphasia and right hemiplegia. On arrival, the symptoms had improved. Magnetic resonance (MR) imaging showed left middle cerebral artery stenosis; however, there was no cerebral infarction. DSA was performed post-admission to examine middle cerebral artery stenosis, which showed no middle cerebral artery stenosis but left internal carotid artery (ICA) origin stenosis and contrast pooling. We diagnosed a transient ischemic attack due to artery-to-artery embolism caused by left ICA stenosis and accompanied by a contralateral carotid web. The same symptoms appeared 6 days later. MR imaging showed a new cerebral infarction and the left middle cerebral artery occlusion. A mechanical thrombectomy procedure revealed a change in ICA origin shape compared to the 1st time, with a shelf-like defect within the carotid web. She subsequently underwent carotid artery stenting and was discharged with mild dysesthesia in her right fingers (modified Rankin Scale of 1).

Conclusion

Thrombus on the carotid web conceals characteristic shelf-like defects and may cause misdiagnosis. However, contrast pooling and contralateral carotid web are important findings for early treatment.

Carotid Web Management in Symptomatic Patients: A Case Report and Literature Review

The carotid web is a rare fibromuscular dysplasia disease of the internal carotid artery wall. It is a cause of thromboembolic stroke in a demographic of patients generally younger than those with atherosclerotic carotid artery disease. It is easy to miss the diagnosis without a high index of suspicion. We present a case of a carotid web in a 36-year-old female who suffered a thromboembolic stroke as a result of an ipsilateral carotid web. This was managed with open surgical resection of the intimal web and bovine patch angioplasty. In addition to highlighting this pathology as a cause of internal carotid artery stenosis, we present a review of the literature and a consensus on management options.

Current Therapy for Carotid Webs

BACKGROUND

Carotid webs are a potential cause of ischemic stroke, particularly in younger patients with few traditional risk factors. Despite advances in imaging technology, the management of carotid webs remains poorly defined due to its rarity, absence of evidence-based guidelines, and the unique challenges presented by these lesions. This narrative review evaluates current knowledge on carotid web management, emphasizing diagnostic features, pathophysiological considerations, and treatment strategies.

METHODS

A literature search was conducted using PubMed and Google Scholar databases with search terms "carotid web management," "carotid web treatment," and "carotid web," focusing on studies published between 2014 and 2024.

RESULTS

Carotid webs are a variant of fibromuscular dysplasia and represent a potential source of embolic strokes. Despite the low overall prevalence, they account for a significant proportion of strokes in younger patients, with a high risk of recurrence when managed medically. Diagnosis often requires advanced imaging, such as computed tomography angiography or magnetic resonance angiography. Treatment options include medical management, carotid endarterectomy, and stenting, though no consensus guidelines exist. Medical management alone has a high recurrent stroke risk.

CONCLUSIONS

Carotid webs should be included in the differential diagnosis of patients with cryptogenic stroke, particularly in younger individuals. Given the high recurrence rates with medical management, both endarterectomy and stenting are recognized as safe and effective treatment options. Future prospective studies are needed to determine the optimal management strategy, including the role of preoperative anticoagulation and comparative outcomes of different treatment modalities.

Optical Coherence Tomography in the Evaluation of Suspected Carotid Webs

BACKGROUND

Carotid web (CaW) is a subtype of fibromuscular dysplasia that predominantly involves the intimal layer of the arterial wall and is commonly overlooked as a separate causative entity for recurrent strokes. CaW is defined as a shelf-like lesion at the carotid bulb, although different morphological features have been reported. Optical coherence tomography (OCT) has been described in the literature as a useful microscopic and cross-sectional tomographic imaging tool. This study aimed to evaluate the potential utility of OCT in characterizing the wall structure features of patients with suspected CaW.

METHODS

Retrospective analysis of patients with suspected CaW who underwent digital subtraction angiography (DSA) coupled with OCT of the carotid bulb from 2018 to 2021 in a single comprehensive stroke center.

RESULTS

Sixteen patients were included. The median age was 56 years (IQR 46-61) and 50% were women. OCT corroborated the diagnosis of CaW in 12/16 (75%) cases and ruled it out in 4/16 (25%) patients in whom atherosclerotic disease was demonstrated. Five of the 12 lesions demonstrated a thick fibrotic ridge consistent with CaW but also showed atherosclerotic changes in the vicinity of the carotid bulb (labeled as "CaW+"). In 4/16 (25%) patients, microthrombi adhered to the vessel wall were noted on OCT (inside the CaW pocket or just distal to the web), none of which were observed on CT angiography or DSA.

CONCLUSIONS

OCT may have value as a complementary imaging tool in the investigation of patients with suspected CaW and atypical morphological features. Further studies are warranted.

Symptomatic carotid webs and patent foramen ovale: RoPE score in competing stroke etiologies

BACKGROUND

Patent foramen ovale (PFO)-associated stroke is diagnosed more frequently in young patients with infrequent vascular risk factors and embolic appearing infarcts. The risk of paradoxical embolism (RoPE) score is used to identify PFO-associated stroke. Patients with symptomatic carotid artery web (CaW) share a very similar risk profile and these lesions are frequently overlooked. In this study, we evaluate the RoPE score profile in patients with suspected symptomatic CaW.

METHODS

Retrospective analysis of prospectively collected data of patients with symptomatic CaW as the presumed cause of stroke presenting to 2 comprehensive stroke centers from 2014 to 2021. CaW was diagnosed using computed tomography angiography (CTA) of the neck & head. Shunt study was done using a transthoracic, transesophageal, and/or transcranial-Doppler with bubbles. RoPE score ≥7 was considered high.

RESULTS

Seventy-five patients had stroke from a symptomatic ipsilateral CaW. Mean age was 49.7±11.2 years and 74.7 % were females. Median RoPE score was 7 [5-8], and 52.0 % had a high RoPE score. PFO was detected in 13.3 % of the patients and 20.5 % within the high RoPE score group. Ten percent of the cases would have been misclassified as PFO-associated strokes based on RoPE score.

CONCLUSION

High RoPE scores were observed in the majority of patients with CaW-attributed stroke, and it should not be used to differentiate CaW- versus PFO-associated stroke. Careful extracranial internal carotid artery evaluation for CaW is warranted in cryptogenic strokes, including in PFO positive patients before defining stroke etiology.

The Carotid Web: A Rare Abnormality of the Intimal Layer Causing Ischemic Stroke in a Young Female Patient

The carotid web represents a specific type of fibromuscular dysplasia that primarily affects the intimal layer and is considered a high-risk factor for cryptogenic ischemic stroke. There is still debate regarding the ideal diagnostic imaging for carotid webs. Computed tomography angiography (CTA) is the preferred method in most studies; however, digital subtraction angiography (DSA) has been proven to offer great-quality images for diagnosing and evaluating the carotid web. Surgical treatment of carotid web is essential in order to avoid recurrent attacks of ischemic stroke. Carotid endarterectomy (CEA) and carotid artery stenting (CAS) are both indicated for the treatment of carotid web; on the other hand, the efficacy of conservative treatment is still debated. We present a case of ischemic stroke in a young female patient that was attributed to a carotid web and was treated successfully with CAS of the right internal carotid artery.

Relationship between carotid web morphology on CT angiography and stroke: A pooled multicenter analysis

BACKGROUND

The Carotid web (CaW) is a cause of stroke, particularly in younger individuals. However, the frequency and the radiological features of the web's morphology associated with stroke risk are uncertain. We determined the CaW radiological features on computed tomography (CT) angiography associated with ipsilateral stroke.

MATERIALS AND METHODS

Data from six studies of patients with acute ischemic stroke were pooled. Identification and measurement of CaWs were performed by experienced readers using baseline neck CT angiography. We assessed six 2D CaW radiological features on sagittal oblique images, namely, main axis length, thickness, height, base width, distance to wall, and angle between the web main axis and carotid wall, and CaW volume on 3D images. CaWs were divided into symptomatic if acute ischemic stroke was in the ipsilateral internal carotid artery territory and its etiology was undetermined and asymptomatic if one condition was unmet. Univariable and multivariable analyses were conducted to assess the association between each radiological CaW feature and symptomatic CaW.

RESULTS

Of the 3442 patients in the pooled data with assessable CTAs, 60 (1.7%) had CaW. In patients with CaW, median age was 59 (interquartile range [IQR]: 50-68) years, 60% were women, and 3 patients had bilateral CaWs. There were 39 (62%) symptomatic and 24 (38%) asymptomatic CaWs. Patients with symptomatic CaW were younger (55 (IQR: 49-61) years versus 69 (IQR: 52-75) years), had lower rates of hypertension (9 (25.0%) versus 12 (57.1%)) and more intracranial large vessel occlusions compared to patients with asymptomatic CaWs. After adjusting for age, hypertension, and occlusion location, CaW length (adjusted odds ratio (aOR) 1.84 (95% confidence interval [CI]: 1.03-3.28)), thickness (aOR: 2.31 (95% CI 1.08-4.97)), volume (aOR: 1.07 per 1 mm3 increment (95% CI: 1.01-1.12)), and angle relative to the carotid wall (aOR: 0.95 (95% CI: 0.91-0.99)) were associated with symptomatic CaW.

CONCLUSION

Radiological assessment of CaW morphology may determine its potential causal role in ischemic stroke etiology. Symptomatic CaWs tend to be longer, larger, and oriented at more acute angles relative to the carotid wall as compared to asymptomatic CaWs.

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.

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.

Brazilian Angiology and Vascular Surgery Society Guidelines for the treatment of extracranial cerebrovascular disease

Extracranial cerebrovascular disease has been the subject of intense research throughout the world, and is of paramount importance for vascular surgeons. This guideline, written by the Brazilian Society of Angiology and Vascular Surgery (SBACV), supersedes the 2015 guideline. Non-atherosclerotic carotid artery diseases were not included in this document. The purpose of this guideline is to bring together the most robust evidence in this area in order to help specialists in the treatment decision-making process. The AGREE II methodology and the European Society of Cardiology system were used for recommendations and levels of evidence. The recommendations were graded from I to III, and levels of evidence were classified as A, B, or C. This guideline is divided into 11 chapters dealing with the various aspects of extracranial cerebrovascular disease: diagnosis, treatments and complications, based on up-to-date knowledge and the recommendations proposed by SBACV.

Subjects with carotid webs demonstrate pro-thrombotic hemodynamics compared to subjects with carotid atherosclerosis

Carotid artery webs (CaW) are non-atherosclerotic projections into the vascular lumen and have been linked to up to one-third of cryptogenic strokes in younger patients. Determining how CaW affects local hemodynamics is essential for understanding clot formation and stroke risk. Computational fluid dynamics simulations were used to investigate patient-specific hemodynamics in carotid artery bifurcations with CaW, bifurcations with atherosclerotic lesions having a similar degree of lumen narrowing, and with healthy carotid bifurcations. Simulations were conducted using segmented computed tomography angiography geometries with inlet boundary conditions extracted from 2D phase contrast MRI scans. The study included carotid bifurcations with CaW (n = 13), mild atherosclerosis (n = 7), and healthy bifurcation geometries (n = 6). Hemodynamic parameters associated with vascular dysfunction and clot formation, including shear rate, oscillatory shear index (OSI), low velocity, and flow stasis were calculated and compared between the subject groups. Patients with CaW had significantly larger regions containing low shear rate, high OSI, low velocity, and flow stasis in comparison to subjects with mild atherosclerosis or normal bifurcations. These abnormal hemodynamic metrics in patients with CaW are associated with clot formation and vascular dysfunction and suggest that hemodynamic assessment may be a tool to assess stroke risk in these patients.

Application of bolus tracking: The effect of ROI positions on the images quality of cervicocerebral CT angiography

Background

Cervicocerebral CT angiography (CTA) using the bolus tracking technique has been widely used for the assessment of cerebrovascular diseases. Regions of interest (ROI) can be placed in the descending aorta, ascending aorta, and the aortic arch. However, no study has compared the arteries and veins display when when the region of interest (ROI) is placed at different sites. In this study, we showed the impact of ROI positions on the image quality of cervicocerebral CTA.

Methods

Two hundred and seventy patients who underwent cervicocerebral CTA with bolus tracking technique were randomly divided into three groups based on the position of the ROI placement: ascending aorta (Group 1, n = 90), aortic arch (Group 2, n = 90), and descending aorta (Group 3, n = 90). The scanning parameters and contrast agent injection protocols were consistent across all groups. Three observers independently assessed the objective image quality, while two observers jointly assessed the subjective image quality using a grade scale: poor (grade 1), average (grade 2), good (grade 3), and excellent (grade 4). The differences in intravascular CT values, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), AVCR (arterial venous contrast ratio), and subjective image quality scores were compared among the three groups.

Results

The CT values of the intracranial veins (superior sagittal sinus, ethmoid sinus and great cerebral vein) in group 1 were significantly lower than those in group 3 (p < 0.001). However, no significant differences were observed in CT values, SNR and CNR in the internal carotid artery and middle cerebral artery among the three groups. The proportion of images with grade 4 was significantly higher in group 1 than group 2 and 3 (41.1% vs 15.6% and 13.3%, p < 0.001). The proportion of images with grade 1 was significantly lower in group 1 than group 2 and 3 (1.1% vs 6.6% and 17.8%, p < 0.001).

Conclusion

The ROI positions for cervicocerebral CTA did not affect the arterial image quality, but venous structures imaging was affected when the ROI was placed in the ascending aorta.

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.

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.

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.

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.

Impact on hemodynamics in carotid arteries with carotid webs at different locations: A Numerical Study Integrating Thrombus Growth Model

OBJECTIVE

Carotid webs (CWs), lesions in the carotid arteries, are gaining research interest due to the unclear link to ischemic stroke. Similarity to atherosclerosis in lesion location adds the complexity. The main purpose of study is to investigate the hemodynamic effects of CWs at different locations in carotid arteries.

METHODS

Three types of models with CWs were reconstructed from the CTA dataset of 8 healthy carotid arteries (Models A: CWs at the common carotid artery; B: at the origin of internal carotid artery; C: at the carotid sinus). Wall shear stress (WSS)-based parameters, including time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), relative residence time (RRT), and endothelial cell activation potential (ECAP) were analyzed. A thrombus growth model was also incorporated to assess long-term thrombus formation across different carotid webs locations.

RESULTS

Models A exhibited helical flow, whereas models B and C showed disturbed flow in the carotid sinus. Recirculation in Models A and B was mainly downstream of CWs, while Models C had both upstream and downstream recirculation. In addition, models A had higher overall TAWSS levels, with the smallest region of TAWSS < 0.4 pa (7.78 ± 8.35%). In contrast, Models C had larger areas with TAWSS < 0.4 pa, RRT > 100, and ECAP > 1.5, accounting for 14.18 ± 5.28%, 1.51 ± 1.17%, and 10.36 ± 4.10%, respectively. Noting that thrombus volume was highest in Models C (7.20 ± 3.95%).

CONCLUSIONS

Numerical simulations indicate that: 1) CWs have less hemodynamic impact when located in the CCA, but may increase flow resistance leading to distal branch ischemia; 2) CWs contribute to thrombus formation, primarily downstream in the common carotid artery and internal carotid artery origin, and both upstream and downstream in the sinus; 3) CWs at the origin of the ICA are more likely to result in disturbed blood flow patterns and thrombus aggregation than the other two locations, which may increase the risk of ischemic stroke in distal cerebral arteries.

Multimodal Neuroimaging Reveals and Guides Treatment of a Middle Cerebral Artery Web

This case report describes how neuroimaging was used to determine treatment for episodic sudden-onset weakness and numbness in the left limbs.

Recurrent stroke shortly after mechanical thrombectomy secondary to carotid web: A case report

RATIONALE

Carotid web, a known source of thrombus for embolic stroke, presents a considerable risk of stroke recurrence. While case reports have demonstrated the safety and effectiveness of mechanical thrombectomy in treating carotid web-related stroke, the need for concurrent carotid artery stenting to prevent recurrent stroke immediately after thrombectomy remains unclear. This study aims to underscore the importance of immediate carotid artery stenting in preventing recurrent stroke following mechanical thrombectomy in patients with carotid web-related stroke.

PATIENT CONCERNS

A 43-year-old woman with acute onset of left limb weakness and slurred speech within 3 hours was admitted to the emergency department.

DIAGNOSES

Computed tomographic angiography confirmed the M1 segment occlusion of the right middle cerebral artery.

INTERVENTIONS

The patient received intravenous thrombolysis in the local hospital and mechanical thrombectomy in our stroke center.

OUTCOMES

Three days post-mechanical thrombectomy, there was a sudden exacerbation of her neurological deficit symptoms. A reexamination via computed tomographic angiography revealed a re-occlusion in M1 segment of the right middle cerebral artery, despite the implementation of stringent anticoagulation therapy for carotid web-related stroke.

LESSONS

Stroke patients with carotid web had a high risk of stroke recurrence and it was necessary to conduct carotid artery stenting to prevent stroke recurrence secondary to the carotid web immediately after mechanical thrombectomy.

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.

The efficacy and safety of general anesthesia vs. conscious sedation for endovascular treatment in patients with acute ischemic stroke: a systematic review and meta-analysis

Background

Endovascular thrombectomy (EVT) is an important treatment for patients with acute ischemic stroke (AIS). A number of studies have suggested that anesthesia type (conscious sedation vs. general anesthesia) during intra-arterial treatment for acute ischemic stroke has implications for patient outcomes.

Methods

PubMed, EMBASE, Cochrane Library and clinicaltrials.gov were searched for randomized controlled trials (RCTs) that were performed to evaluate general anesthesia (GA) and conscious sedation (CS) up to May 30, 2023. Review Manager 5.3 software was used to assess the data. The risk ratio (RR) and mean difference (MD) were analyzed and calculated with a fixed effect model.

Results

We pooled 930 patients from seven RCTs. We conducted a meta-analysis comparing the outcomes of GA and CS in the included trials. The rate of functional independence in the GA group was higher than that in the CS group (RR: 1.17, 95% CI: 1.00-1.35; P = 0.04; I2 = 16%). The GA group had a higher successful recanalization rate than the CS group (RR: 1.15, 95% CI: 1.08-1.22; P < 0.0001; I2 = 26%). The GA group had a higher pneumonia rate than the CS group (RR: 1.69, 95% CI: 1.22-2.34; P = 0.002; I2 = 26%). In addition, there was no significant difference between GA and CS with respect to the National Institutes of Health Stroke Scale (NIHSS) score at 24 h (P = 0.62), Modified Rankin Scale (mRS) score at 90 days (P = 0.25), intracerebral hemorrhage (P = 0.54), and mortality at 3 months (P = 0.61).

Conclusion

GA demonstrated superiority over CS in achieving successful recanalization and functional independence at 3 months when performing EVT in AIS patients. However, it was also associated with a higher risk of pneumonia. Further studies, particularly those with long-term follow-ups, are necessary to identify precise strategies for selecting the appropriate anesthetic modality in EVT patients.

Systematic review registration

INPLASY202370116.

[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.

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.

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.

Neuroinflammation and anti-inflammatory therapy for ischemic stroke

Stroke remains one of the most devastating and challenging neurological diseases worldwide. Inflammation, as well as oxidative stress is one of the main contributors to post-stroke injuries, and oxidative stress can further induce inflammation. Moreover, the inflammatory response is closely related to immune modulation in ischemic stroke progression. Hence, major ischemic stroke treatment strategies include targeting inflammatory responses, immune modulation (especially immune cells), and inflammatory response to suppress stroke progression. To date, several drugs have demonstrated clinical efficacy, such as Etanercept and Fingolimod. However, only edaravone dexborneol has successfully passed the phase III clinical trial and been approved by the National Medical Products Administration (NMPA) to treat ischemic stroke in China, which can restore redox balance and regulate inflammatory immune responses, thus providing neuroprotection in ischemic stroke. In this review, we will comprehensively summarize the current advances in the application of inflammatory biomarkers, neuroinflammation and neuro-immunotherapeutic scenarios for ischemic stroke, thus aiming to provide a theoretical basis and new prospects and frontiers for clinical applications.

TRIM67 alleviates cerebral ischemia‒reperfusion injury by protecting neurons and inhibiting neuroinflammation via targeting IκBα for K63-linked polyubiquitination

BACKGROUND

Excessive and unresolved neuroinflammation plays an important role in the pathophysiology of many neurological disorders, such as ischemic stroke, yet there are no effective treatments. Tripartite motif-containing 67 (TRIM67) plays a crucial role in the control of inflammatory disease and pathogen infection-induced inflammation; however, the role of TRIM67 in cerebral ischemia‒reperfusion injury remains poorly understood.

RESULTS

In the present study, we demonstrated that the expression level of TRIM67 was significantly reduced in middle cerebral artery occlusion and reperfusion (MCAO/R) mice and primary cultured microglia subjected to oxygen-glucose deprivation and reperfusion. Furthermore, a significant reduction in infarct size and neurological deficits was observed in mice after TRIM67 upregulation. Interestingly, TRIM67 upregulation alleviated neuroinflammation and cell death after cerebral ischemia‒reperfusion injury in MCAO/R mice. A mechanistic study showed that TRIM67 bound to IκBα, reduced K48-linked ubiquitination and increased K63-linked ubiquitination, thereby inhibiting its degradation and promoting the stability of IκBα, ultimately inhibiting NF-κB activity after cerebral ischemia.

CONCLUSION

Taken together, this study demonstrated a previously unidentified mechanism whereby TRIM67 regulates neuroinflammation and neuronal apoptosis and strongly indicates that upregulation of TRIM67 may provide therapeutic benefits for ischemic stroke.

Carotid Web as an Embolic Source of Acute Ischemic Stroke

INTRODUCTION

Carotid webs are shelf-like projections of the carotid bulb lumen associated with ipsilateral ischemic stroke in young patients. Given its rarity, a limited number of studies have evaluated the optimal management of symptomatic carotid webs to prevent further ischemic stroke.

CASE REPORT

A 40-year-old Caucasian man presented with a sudden onset of left-sided facial droop, hemiparesis, and dysarthria. Computed tomography angiography revealed occlusion of the distal M1 and proximal M2 segments of the right middle cerebral artery and a small intimal flap at the right internal carotid artery origin. Intravenous alteplase was administered without clinical improvement. The patient underwent successful mechanical thrombectomy with complete revascularization of the middle cerebral artery and no residual neurologic deficits. Magnetic resonance angiography confirmed a curvilinear, shelf-like projection from the right carotid bulb posterior wall, consistent with a carotid web. The patient underwent carotid endarterectomy with no complications and was discharged home with no residual deficits or recurrence of stroke.

CONCLUSION

No randomized, controlled prospective studies have compared the efficacy of endarterectomy to carotid artery stenting in patients with symptomatic carotid web. This case emphasizes the importance of considering carotid web as an embolic source of stroke in the young and provides support for revascularization as a safe and effective mean of secondary stroke prevention.

Use of intravascular optical coherence tomography to confirm the diagnosis of a carotid web in a patient with recurrent ipsilateral embolic strokes and evaluate the response to stenting

A Carotid web (CaW) is defined as a focal shelf-like projection of non-atheromatous, fibrous tissue along the posterior wall of the carotid bulb. CaW are rare and commonly overlooked lesions increasingly recognized as a cause of stroke in otherwise healthy patients. Intravascular imaging modalities such as intravascular ultrasound and optical coherence tomography (OCT) have been proposed as an adjunct to digital subtraction angiography for the evaluation of CaW. However, the use of OCT in CaW has yet to be described. This report investigated the utility of OCT as an adjunct imaging modality in the evaluation of CaW morphology in a young patient with recurrent ischemic 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.

Diagnostic Ultrasonography in Neurology

OBJECTIVE

Ultrasonography allows neurologists to complement clinical information with additional useful, easily acquired, real-time data. This article highlights its clinical applications in neurology.

LATEST DEVELOPMENTS

Diagnostic ultrasonography is expanding its applications with smaller and better devices. Most indications in neurology relate to cerebrovascular evaluations. Ultrasonography contributes to the etiologic evaluation and is helpful for hemodynamic diagnosis of brain or eye ischemia. It can accurately characterize cervical vascular atherosclerosis, dissection, vasculitis, or other rarer disorders. Ultrasonography can aid in the diagnosis of intracranial large vessel stenosis or occlusion and evaluation of collateral pathways and indirect hemodynamic signs of more proximal and distal pathology. Transcranial Doppler (TCD) is the most sensitive method for detecting paradoxical emboli from a systemic right-left shunt such as a patent foramen ovale. TCD is mandatory for sickle cell disease surveillance, guiding the timing for preventive transfusion. In subarachnoid hemorrhage, TCD is useful in monitoring vasospasm and adapting treatment. Some arteriovenous shunts can be detected by ultrasonography. Cerebral vasoregulation studies are another developing field of interest. TCD enables monitoring of hemodynamic changes related to intracranial hypertension and can diagnose cerebral circulatory arrest. Optic nerve sheath measurement and brain midline deviation are ultrasonography-detectable signs of intracranial hypertension. Most importantly, ultrasonography allows for easily repeated monitoring of evolving clinical conditions or during and after interventions.

ESSENTIAL POINTS

Diagnostic ultrasonography is an invaluable tool in neurology, used as an extension of the clinical examination. It helps diagnose and monitor many conditions, allowing for more data-driven and rapid treatment interventions.

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.

Importance of multiplanar reformation angiographic images for the detection of carotid web: A case series

Carotid web (CW) is considered a variant of intimal fibromuscular dysplasia. CW represents between 9.4% and 37% of ischemic strokes that were initially misclassified as "cryptogenic." However, in Latin America, there is a lack of detection. We present 5 cases of ischemic stroke due to CW and discuss the usefulness of multiplanar reformatting (MPR) imaging in computed tomography angiography. The identification of CW with the use of tridimensional (3D) reconstructions and maximum intensity projection was 20%, the rest was misdiagnosed as atherosclerotic plaque. With the MPR, the identification of typical CW findings was improved, such as a thin septum, a shelf-like image, and a mountain shadow-like image. However, one must be alert to changes in the 3D disposition of the carotid bifurcation, as they may mask the typical CW findings. A good practice is to align the internal carotid artery exactly posterior to the external carotid artery in the sagittal plane.

Ultrasound characteristics of carotid web

BACKGROUND AND PURPOSE

Carotid web (CaW) is a cause of recurrent ischemic stroke that remains underdiagnosed using Duplex ultrasound (DUS). Improved methods and description of its ultrasound's features could allow better detection of CaW. Ultrasound microflow imaging (MFI) is a blood flow imaging technique sensitive to slow flow that could increase CaW detection. This study aimed to describe ultrasound features of CaW using B-mode imaging and MFI.

METHODS

In a retrospective monocentric study, patients with CaW on CT angiography who underwent DUS examination of carotid arteries were included. DUS was performed by two nonblinded experienced neurosonologists. The specificity of CaW ultrasound features was evaluated using a group of patients with carotid atherosclerotic plaque (AP).

RESULTS

Twenty-four patients with CaW were included. Mean age (standard deviation) was 48 years (11). Seventeen (71%) were females. Fifteen (63%) CaWs were symptomatic. MFI was available for 22 patients. B-mode imaging demonstrated the characteristic CaW appearance in 19/24 (79%) patients as a protruding triangular iso-hypoechoic lesion on longitudinal view. CaW were detected on axial view in only 9/24 (38%) patients. MFI displayed slow blood flow above CaW during systole and allowed it delineation, appearing as a thin triangular endoluminal defect in 18/22 (82%) cases. Based on MFI and B-mode, 21/22 (95%) CaWs were visible, including three CaWs only with MFI. These ultrasound features were not found among 24 patients with AP.

CONCLUSION

We report the ultrasound features from a series of 24 CaW. The use of MFI in addition to B-mode imaging improved the detection rate of CaW.

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.