Faculty Bibliography

BACKGROUND:Carotid webs are increasingly recognized as a significant cause of cryptogenic stroke in young adults, yet they remain frequently underdiagnosed due to their subtle radiographic appearance and atypical presentations. The natural history of untreated carotid webs includes high rates of recurrent ipsilateral ischemic events despite optimal medical therapy. OBSERVATIONS/METHODS:The authors present the case of a 44-year-old man with four recurrent right hemispheric ischemic events over 5 years. Despite multiple angiographic studies, an underlying carotid web was initially misinterpreted. Digital subtraction angiography ultimately revealed a subtle posterolateral carotid web. Prior to endarterectomy, intraoperative ultrasound uniquely visualized a large thrombus adherent to the web, a critical finding not appreciated on preoperative angiography. Successful en bloc removal of the web and thrombus was performed with histopathological confirmation. The patient remained stroke free at the 1-year follow-up. LESSONS/CONCLUSIONS:Atypical carotid webs may lack classic radiographic features and can be misclassified on noninvasive imaging. Intraoperative ultrasound provides real-time assessment of thrombus burden not visible on preoperative angiography, allowing for improved surgical planning. This case demonstrates that web-associated thrombi are dynamic and may not be apparent even on high-resolution angiography performed shortly before surgery. Surgical intervention with intraoperative ultrasound guidance offers definitive treatment and excellent long-term outcomes. https://thejns.org/doi/10.3171/CASE2610.

BACKGROUND AND OBJECTIVES/UNASSIGNED:The aim of this study was to assess the limitations of a traditional twice-daily lecture format and evaluate the feasibility and impact of implementing an academic half-day (AHD) for neurology residents at a multisite academic institution. AHD has the potential to improve attendance, satisfaction, and clinical competency compared with traditional didactics in graduate medical education. However, its feasibility and impact within neurology residency programs remain underexplored, with few adopting this model to date. Coverage logistics, faculty availability, and neurologic emergencies continue to pose challenges, particularly in large, multisite institutions. METHODS/UNASSIGNED:A needs assessment survey was administered to 36 neurology residents (postgraduate year [PGY]2-PGY4) in spring 2024 to evaluate attendance, satisfaction, and suggestions for improvement. Attendance was recorded over 1 month (August 2024). Based on survey feedback, a new 3.5-hour AHD curriculum was developed collaboratively by residents and faculty, held Tuesday mornings every week with varied lecture formats. One resident per class covered urgent clinical duties at each of 3 sites, while faculty and advanced practice providers (APPs) independently conducted rounds. Attendance was recorded for one month after implementation (September 2024), and surveys were distributed to assess satisfaction with both the curriculum and the coverage model. Residency In-Training Examination (RITE) scores were compared between the 2022 and 2024 cohorts (before AHD) and the 2025 cohort (after AHD implementation). RESULTS/UNASSIGNED:= 0.0013). Faculty and APPs reported positive or neutral effects on workflow (82.6% and 100%, respectively) and patient safety (95.6% and 100%, respectively). DISCUSSION/UNASSIGNED:Implementation of AHD across a large, multisite neurology residency program was feasible and associated with higher attendance, improved resident satisfaction, and enhanced RITE performance, without adverse effects on workflow or patient safety. Key factors for success included resident involvement, a targeted needs assessment, and strong coverage support from faculty and APPs.

OBJECTIVE:To validate the carotid web (CW) risk stratification assessment described in previous works within a larger cohort of patients with symptomatic and incidentally found asymptomatic CWs. METHODS:A retrospective analysis of our institution's electronic medical records identified all patients with a diagnosis of CW from 2017 to 2024. We included symptomatic patients and those with asymptomatic CWs, that is, incidentally found webs without history of stroke or transient ischemic attack. Patient charts were reviewed for demographics, imaging, comorbidities, and a diagnosis of stroke after diagnosis of asymptomatic CW. All angles were measured as described in previous work on a sagittal reconstruction of neck CT angiography in which the common carotid artery (CCA), external carotid artery, and internal carotid artery (ICA) were well visualized, together with the CW itself. Principal component analysis and logistic regression were performed to evaluate the association between high-risk angles and stroke risk.  RESULTS: Twenty-six symptomatic and 26 asymptomatic patients were identified. Of note, the number of patients with hypertension, hyperlipidemia, and smoking history was 17 (65.0%), 16 (62.0%), and 8 (31.0%) for symptomatic patients and 18 (69.0%), 17 (65.0%), and 15 (58.0%) for asymptomatic patients. All angular measurements showed statistically significant associations with stroke status. The CCA-web-pouch angle showed the strongest association (p=2.07×10⁻⁴), followed by the CCA-pouch-tip angle (p=3.23×10⁻⁴), ICA-web-pouch angle (p=0.004), and ICA-pouch-tip angle (p=0.005). Each additional high-risk angle increased the odds of stroke by 9.47-fold (p<0.0001). The associated probability of stroke increased from 6.3% with no high-risk angles to 39.1% with one high-risk angle and further to 85.9% with two high-risk angles. The model demonstrated high sensitivity, correctly identifying 84.6% of positive cases, and high specificity, correctly identifying 88.5% of negative cases. The F1 score was 0.863, indicating good overall model performance.  CONCLUSION: Given this successful stratification of CWs into high- and low-risk groups, the utilization of geometric CW parameters may play a role in improving patient selection for intervention in the setting of incidentally diagnosed CW. .

Typical carotid webs are nonatherosclerotic shelf-like projections of fibromyxoid tissue extending from the posterior wall of the proximal internal carotid artery (ICA). 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. Our electronic medical record database was queried for all imaging impressions containing "carotid web," "shelf," or "protrusion" from 2018-2024. 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. Twenty-seven patients were treated for typical carotid webs; 24 were treated with carotid endarterectomy (CEA) and had pathology-confirmed webs. Five patients (three male) were identified to have ACWs and included in this report. Mean age was 43.6 years. All ACWs were identified by computed tomography angiography (CTA). All patients presented with acute ischemic stroke or transient ischemic attack (TIA). One web was located on the anterior ICA wall, three were of abnormal morphology different from a "shelf-like" projection, and one was associated with atherosclerotic change. No patients experienced a further stroke or TIA following CEA. 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.

Large vessel occlusion stroke due to underlying intracranial atherosclerotic disease (ICAD-LVO) is prevalent in 10 to 30% of LVOs depending on patient factors such as vascular risk factors, race and ethnicity, and age. Patients with ICAD-LVO derive similar functional outcome benefit from endovascular thrombectomy as other mechanisms of LVO, but up to half of ICAD-LVO patients reocclude after revascularization. Therefore, early identification and treatment planning for ICAD-LVO are important given the unique considerations before, during, and after endovascular thrombectomy. In this review of ICAD-LVO, we propose a multistep approach to ICAD-LVO identification, pretreatment and endovascular thrombectomy considerations, adjunctive medications, and medical management. There have been no large-scale randomized controlled trials dedicated to studying ICAD-LVO, therefore this review focuses on observational studies.

BACKGROUND:Intracranial stenosis (ICAS) is a common cause of stroke worldwide and patients with symptomatic ICAS exhibit a high rate of recurrence, particularly in the early period after the initial event. In this study, we aimed to study the association between borderzone infarct and recurrent ischemic stroke in patients hospitalized with symptomatic ICAS. METHODS:This is a retrospective single center study that included patients hospitalized with acute ischemic stroke in the setting of intracranial stenosis (50% or more and an acute ischemic stroke in the territory supplied by the stenosed artery) over a 32-month period. We excluded patients who did not receive a brain MRI or did not have an infarct on brain imaging. The primary predictor is infarct pattern (any borderzone vs. no borderzone infarct) and the primary outcome was recurrent cerebrovascular events (RCVE) within 90 days. We used unadjusted, and age and sex adjusted logistic regression models to determine associations between infarct pattern and RCVE at 90-days. RESULTS:Among 99 patients who met the inclusion criteria (4 tandem), the mean age was 70.1 ± 11.2 years and 41.4% were women; 43 had borderzone infarcts and 19 had RCVE. In adjusted binary logistic regression analysis, borderzone infarct was associated with increased risk of RCVE (adjusted OR 4.00 95% CI 1.33-11.99, p=0.013). The association between borderzone infarction and RCVE was not different among anterior circulation ICAD (adjusted HR 2.85 95% CI 0.64-12.76, p=0.172) vs. posterior circulation ICAD (adjusted HR 6.69 95% CI 1.06-42.11, p=0.043), p-value for interaction = 0.592. CONCLUSION/CONCLUSIONS:In real world post-SAMMPRIS medically treated patients with ICAD, the borderzone infarct pattern was associated with 90-day RCVE. Borderzone infarcts are likely a surrogate marker of impaired distal blood flow, highlighting the importance of targeting stroke mechanisms and developing alternative treatment strategies for high-risk cohorts.

Importance/UNASSIGNED:In the Platelet-Oriented Inhibition in New TIA and Minor Ischemic Stroke (POINT) trial, acute treatment with clopidogrel-aspirin was associated with significantly reduced risk of recurrent stroke. There may be specific patient groups who are more likely to benefit from this treatment. Objective/UNASSIGNED:To investigate whether the association of clopidogrel-aspirin with stroke recurrence in patients with minor stroke or high-risk transient ischemic attack (TIA) is modified by the presence of infarct on imaging attributed to the index event (index imaging) among patients enrolled in the POINT Trial. Design, Setting, and Participants/UNASSIGNED:In the POINT randomized clinical trial, patients with high-risk TIA and minor ischemic stroke were enrolled at 269 sites in 10 countries in North America, Europe, Australia, and New Zealand from May 28, 2010, to December 19, 2017. In this post hoc analysis, patients were divided into 2 groups according to whether they had an acute infarct on index imaging. All POINT trial participants with information available on the presence or absence of acute infarct on index imaging were eligible for this study. Univariable Cox regression models evaluated associations between the presence of an infarct on index imaging and subsequent ischemic stroke and evaluated whether the presence of infarct on index imaging modified the association of clopidogrel-aspirin with subsequent ischemic stroke risk. Data were analyzed from July 2020 to May 2021. Exposures/UNASSIGNED:Presence or absence of acute infarct on index imaging. Main Outcomes and Measures/UNASSIGNED:The primary outcome is whether the presence of infarct on index imaging modified the association of clopidogrel-aspirin with subsequent ischemic stroke risk. Results/UNASSIGNED:Of the 4881 patients enrolled in POINT, 4876 (99.9%) met the inclusion criteria (mean [SD] age, 65 [13] years; 2685 men [55.0%]). A total of 1793 patients (36.8%) had an acute infarct on index imaging. Infarct on index imaging was associated with ischemic stroke during follow-up (hazard ratio [HR], 3.68; 95% CI, 2.73-4.95; P < .001). Clopidogrel-aspirin vs aspirin alone was associated with decreased ischemic stroke risk in patients with an infarct on index imaging (HR, 0.56; 95% CI, 0.41-0.77; P < .001) compared with those without an infarct on index imaging (HR, 1.11; 95% CI, 0.74-1.65; P = .62), with a significant interaction association (P for interaction = .008). Conclusions and Relevance/UNASSIGNED:In this study, the presence of an acute infarct on index imaging was associated with increased risk of recurrent stroke and a more pronounced benefit from clopidogrel-aspirin. Future work should focus on validating these findings before targeting specific patient populations for acute clopidogrel-aspirin treatment.

PURPOSE OF REVIEW/OBJECTIVE:Patent foramen ovale (PFO) is widely prevalent and studies have suggested an association with ischemic stroke. In this review, we aim to highlight current management of patients with ischemic stroke in the setting of PFO and discuss some areas of controversy. RECENT FINDINGS/RESULTS:Upon reviewing the literature, we have found that the evidence regarding the management of patients with cryptogenic stroke and PFO has come a long way in the past several years, and many uncertainties remain in clinical practice. The Risk of Paradoxical Embolism (RoPE) score helps to predict the probability of a pathogenic PFO, and recent trial data confirms the benefit of closure in carefully selected patients. The benefit of closure in older patients and in patients with alternate, competing mechanisms is still uncertain, and the long-term risks of closure are not known. Finally, the efficacy of direct oral anticoagulants (DOACs) in this patient population as compared to other medical therapy or mechanical closure has not yet been investigated. Randomized data is needed to help answer these questions. PFO closure is a safe and effective strategy in reducing stroke risk in carefully selected patients with cryptogenic stroke in the setting of a PFO. More studies are needed to test optimal medical treatment strategies and the safety and efficacy of PFO closure in patient subgroups not included in prior PFO closure trials.

Since the onset of the COVID-19 pandemic, a substantial proportion of COVID-19 patients had documented thrombotic complications and ischemic stroke. Several mechanisms related to immune mediated thrombosis, the renin angiotensin system, and the effect of SARS-CoV-2 in cardiac and brain tissue may contribute to the pathogenesis of ischemic stroke in patients with COVID-19. Simultaneously, significant strains on global healthcare delivery, including ischemic stroke management, have made treatment of stroke in the setting of COVID-19 particularly challenging. In this review we summarize the current knowledge on epidemiology, clinical manifestation and pathophysiology of ischemic stroke in patients with COVID-19 to bridge the gap from bench to bedside and clinical practice during the most challenging global health crisis of the last decades.