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Tawk, Rabih

A5132731295 | I2801572250

Mayo Clinic

Jacksonville College

Citations 11

Flow Diversion for a Cervical Internal Carotid Artery Aneurysm: A Case Report and Literature Review

Vascular and Endovascular Surgery | September 29, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1177/15385744261494490 | PMID 42809653

Introduction Extracranial internal carotid artery (ICA) aneurysms are rare (<1% of arterial aneurysms) yet clinically significant due to risks of distal embolization, local compressive symptoms, and, less commonly, rupture. High-quality evidence is limited, and no consensus guidelines exist, management is therefore individualized to aneurysm morphology, cervical segment involvement, vessel tortuosity, and operator expertise. Flow diversion with Pipeline Embolization Device (PED) achieves aneurysm exclusion while reconstructing the parent artery and is especially useful in tortuous cervical segments. Clinical Summary A 60-year-old woman with incidentally discovered bilateral cervical ICA aneurysms (left 2.3 cm mid-ICA; right 0.5 cm) and a type III bovine arch underwent PED diversion of the lesion. Via femoral access, a long 6-F Fubuki sheath (Asahi Intecc, Irvine, USA) with Sofia catheter (Micro-Vention, Tustin, USA) support and systemic heparinization (ACT >250 s) enabled deployment of a 5.0 × 25 mm Pipeline Flex (Medtronic Neurovascular, Irvine, USA) across the aneurysm neck. Immediate angiography showed intra-aneurysmal stasis while preserving parent-artery flow . At 12 months, she is asymptomatic with a 70% reduction in the contrast-opacified aneurysm component to 7 mm, and the contralateral small aneurysm remains stable. Conclusion Flow diversion with a PED provided an effective, artery-preserving solution for a mid-cervical ICA aneurysm in tortuous anatomy, achieving immediate flow stasis with parent-artery patency. At 12 months, the patient is asymptomatic with a contrast-opacified component reduced to 7 mm. This case supports using flow diversion for extracranial ICA aneurysms when anatomy is favorable, alongside careful antiplatelet therapy and planned imaging follow-up.
“ICH-CARE”: ICH -integrated C are for A ccelerated R esponse to

No container title available | July 21, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.64898/2026.07.18.26358392

Abstract Introduction Intracerebral hemorrhage (ICH) carries higher morbidity and mortality than ischemic stroke. Recent studies have demonstrated improved patient outcomes by applying ultra-early bundled interventions including blood pressure management, coagulopathy reversal, and osmotic therapy. Effective strategies to deliver these ultra-early treatment options are currently being explored. On December 19th, 2022, the Mayo Clinic Comprehensive Stroke Center (CSC) launched the “ICH Phases” communication system to accelerate ICH patient care. Objective To evaluate adherence to the AHA/ASA guidelines in acute ICH care following the implementation of our novel-tiered paging system. Methods We retrospectively reviewed patients admitted with spontaneous ICH during 2024 and 2025. We excluded traumatic cases. We extracted clinical data such as time to imaging, documentation of ICH score, blood pressure control, reversal of anticoagulation, venous thrombo-embolism (VTE) prophylaxis and discharge disposition. Results Among 67 patients, 68.7% underwent CT imaging within 25 minutes. We documented the ICH score within 6 hours in 82.9% of patients. Nearly 94.7% of patients with SBP>140 mm Hg received antihypertensive therapy, yet only 18% reached target BP within 60 minutes. We completed the reversal of anticoagulation within 120 minutes in 75% of patients. VTE prophylaxis was initiated within 24 hours in 91% of patients. Discussion Our novel system demonstrated adherence to the AHA/ASA guidelines, and time sensitive benchmarks in neuroimaging, reversal of anticoagulation, and VTE prophylaxis. Early BP control remains a challenge, that highlights the discrepancy between guidelines and real-ground implementation. Conclusion A novel tiered paging system is effective for enhancing early ICH care. Such a holistic system remains critical for sustained improvement in quality of care.
Quantitative Prognostic Modeling in Aneurysmal Subarachnoid Hemorrhage: Multicenter Validation of the eSAH Score

No container title available | July 21, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.64898/2026.07.18.26358390

Abstract Background aneurysmal subarachnoid hemorrhage (aSAH) is neurological emergency associated with substantial mortality and disability. Current grading systems such as the modified Fisher Scale (mFS) and World Federation of Neurological Societies (WFNS) score, rely on semiquantitative and examination based assessments. Hence, they demonstrate limited predictive precision. The enhanced subarachnoid hemorrhage (eSAH) score is a simplified quantitative model integrating age, Glasgow Coma Scale (GCS), and cisternal subarachnoid hemorrhage volume (SAHV) to predict clinical outcomes after aSAH. Methods We performed a retrospective multicenter cohort study that included 1088 patients across three tertiary-care centers the United States. Predictive performance for unfavorable functional outcome, in-hospital mortality and delayed cerebral ischemia (DCI) was evaluated using receiver operating characteristic (ROC) analysis and area under the curve (AUC). Comparative analyses were performed and compared to the WFNS and mFS grading systems. Results the eSAH score demonstrated excellent discrimination for unfavorable functional outcome at discharge ( AUC 0.89 ) and in-hospital mortality (AUC 0.87). The DCI subscore demonstrated good discriminatory performance for predicting DCI (AUC 0.77). Compared with conventional grading systems, this was superior to both the WFNS (AUC 0.75) and the mFS ( AUC 0.70). increasing eSAH scores were additionally associated with progressively higher rates of mortality and unfavorable functional outcomes. Conclusion the eSAH score demonstrates strong external validity, reproducibility and superior predictive performance compared with conventional grading systems in a large multicenter cohort. These findings support the clinical utility of quantitative hemorrhage burden integration for early risk stratification in patients with aSAH.
From CHESS to CHECKMATE: A Practical Score for Predicting Shunt Dependency Following Subarachnoid Hemorrhage

No container title available | July 21, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.64898/2026.07.18.26358389

Abstract Objective Shunt-dependent hydrocephalus is a common and costly complication of aneurysmal subarachnoid hemorrhage (aSAH), affecting up to 28% of survivors. Existing prediction tools, including the Chronic Hydrocephalus Ensuing from SAH Score (CHESS), have limited discriminative accuracy. We developed the CHECKMATE score, a clinically practical tool to improve prediction of ventriculoperitoneal shunt dependency after aSAH. Methods In this multicenter retrospective cohort of 486 patients with aSAH from Mayo Clinic (January 1, 2006-December 31, 2021), we used multivariable logistic regression and machine learning to identify independent predictors of ventriculoperitoneal shunt placement. The CHECKMATE score was derived from 5 weighted variables: symptomatic hydrocephalus (10 points), intraventricular hemorrhage (5 points), SAH volume greater than 10 mL (3 points), neutrophil-to-lymphocyte ratio greater than 12 (2 points), and 10-year incremental age thresholds starting at older than 60 years (1 point each). Results Of 486 patients (mean age, 56.3 years; 64.6% female), 137 (28.2%) required ventriculoperitoneal shunt placement. The CHECKMATE score achieved an area under the curve of 0.808 (compared to 0.737 for CHESS), with a sensitivity of 0.85, specificity of 0.67, and negative predictive value of 0.92 at the optimal cutoff of 14 points. Conclusions The CHECKMATE score outperforms CHESS for predicting ventriculoperitoneal shunt dependency after aSAH and is easily used at the bedside. Its high negative predictive value helps identify low-risk patients who may benefit from earlier external ventricular drain weaning and shorter hospital stays.
Predictive modeling of long-term improvement in occlusion outcomes following Woven EndoBridge treatment of cerebral aneurysms: A machine learning approach

Interventional Neuroradiology | November 3, 2025 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1177/15910199251391915 | PMID 41182964

Background The Woven EndoBridge (WEB) device represents an innovative solution for cerebral aneurysm occlusion, particularly for challenging wide-neck bifurcation aneurysms. However, factors affecting sustained occlusion remain poorly understood. We utilized machine learning to attempt to identify predictors of favorable long-term outcomes following WEB treatment. Methods In this multicenter retrospective study, we collected patient demographics, aneurysm characteristics, procedural details, and clinical outcomes. The primary endpoint was improvement in occlusion status, defined as maintained Raymond-Roy Occlusion Classification (RROC) grade 1, or improvement from grade 2 to 1, or from grade 3 to either 2 or 1 on final angiographic follow up. The dataset was split into training (75%) and validation (25%) sets. The CatBoost algorithm was selected based on performance metrics, with Shapley Additive exPlanations (SHAP) values calculated to determine feature importance. Furthermore, a multivariable binomial logistic regression model was performed to validate machine learning findings. Results Among 720 aneurysms from 36 hospitals, 84% showed improvement in occlusion at follow up. Both machine learning and multivariable logistic regression identified aneurysm height as the most consistent correlate of nonimprovement (odds ratio (OR) 0.90 per mm, p = 0.022). In the CatBoost model, the highest-ranking features by SHAP included aneurysm height, patient age, treatment acuity, ACom location, WEB-SLS device, bifurcation anatomy, aneurysm multiplicity, baseline modified Rankin Scale, access route, and partial thrombosis. Conclusions Machine-learning and regression analyses identified consistent predictors of occlusion improvement after WEB treatment, with aneurysm height most strongly linked to nonimprovement. These insights may guide patient selection and follow up. Findings require cautious interpretation and external validation in larger cohorts.
Dramatic Reanimation and Spontaneous Re-Canalization of a Fourth Ventricular Hemorrhage: “REVIVE” Phenomenon

The Neurohospitalist | October 5, 2024 | Volume: 15 | Issue: 2 | Pages: 202-205

10.1177/19418744241289972 | PMID 39544273

Background Intraventricular hemorrhage is a calamitous type of stroke where bleeding into the ventricular system can be defined as: primary, if confined within the ventricles; or secondary, due to intracerebral hemorrhage extending from adjacent parenchyma. Intraventricular blood clot can lead to secondary insult and inflammatory responses that culminates in hydrocephalus as the most common cause of death. Purpose THerein, we report a patient with a high modified Graeb scale and low Glasgow coma scale. She spontaneously recanalized her fourth ventricle, decompressed her reticular activating system with remarkable spontaneous bilateral eye opening, and a consequently experienced a halfway drop in her mGS. Results This is the first reported case of a spontaneous recanalization of 4th ventricle obstruction secondary to IVH without intervention and subsequent dramatic neurological improvement. We believe that the apixaban primarily preserved the liquid state of hemorrhage and her presumed elevated ICP was sufficient to push out the liquified blood in the 4th ventricle into the upper spinal canal , recanalizing the 4th ventricle by continuously creating downward CSF pressure waves. Given the RAS location around the 4th ventricle, we hypothesize spontaneous decompression from the clot lysis triggered the RAS activation with sudden arousal manifested as spontaneous bilateral eyes opening. Hence, we refer to this as the reticular activating system reactivation after ventricular hemorrhage evacuation, or simply the “REVIVE” phenomenon. Conclusion This dramatic improvement from coma to awake state is worthy of recognition for future neurotherapeutic interventions.
Creation of a predictive calculator to determine adequacy of occlusion of the woven endobridge (WEB) device in intracranial aneurysms—A retrospective analysis of the WorldWide WEB Consortium database

Interventional Neuroradiology | August 10, 2024 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1177/15910199241267320 | PMID 39127463

Background Endovascular treatment with the woven endobridge (WEB) device has been widely utilized for managing intracranial aneurysms. However, predicting the probability of achieving adequate occlusion (Raymond–Roy classification 1 or 2) remains challenging. Objective Our study sought to develop and validate a predictive calculator for adequate occlusion using the WEB device via data from a large multi-institutional retrospective cohort. Methods We used data from the WorldWide WEB Consortium, encompassing 356 patients from 30 centers across North America, South America, and Europe. Bivariate and multivariate regression analyses were performed on a variety of demographic and clinical factors, from which predictive factors were selected. Calibration and validation were conducted, with variance inflation factor (VIF) parameters checked for collinearity. Results A total of 356 patients were included: 124 (34.8%) were male, 108 (30.3%) were elderly (≥65 years), and 118 (33.1%) were current smokers. Mean maximum aneurysm diameter was 7.09 mm (SD 2.71), with 112 (31.5%) having a daughter sac. In the multivariate regression, increasing aneurysm neck size (OR 0.706 [95% CI: 0.535–0.929], p = 0.13) and partial aneurysm thrombosis (OR 0.135 [95% CI: 0.024–0.681], p = 0.016) were found to be the only statistically significant variables associated with poorer likelihood of achieving occlusion. The predictive calculator shows a c-statistic of 0.744. Hosmer–Lemeshow goodness-of-fit test indicated a satisfactory model fit with a p-value of 0.431. The calculator is available at: https://neurodx.shinyapps.io/WEBDEVICE/ . Conclusion The predictive calculator offers a substantial contribution to the clinical toolkit for estimating the likelihood of adequate intracranial aneurysm occlusion by WEB device embolization.
Stent-assisted Woven EndoBridge device for the treatment of intracranial aneurysms: an international multicenter study

Journal of Neurosurgery | October 21, 2023 | Volume: 140 | Issue: 4 | Pages: 1071-1079

10.3171/2023.8.jns235 | PMID 37862717

OBJECTIVE The Woven EndoBridge (WEB) device is an intrasaccular flow disruptor designed for wide-necked bifurcation aneurysms. These aneurysms may require the use of a concomitant stent. The objective of this study was to determine the clinical and radiological outcomes of patients undergoing stent-assisted WEB treatment. In addition, the authors also sought to determine the predictors of a concomitant stent in aneurysms treated with the WEB device. METHODS The data for this study were taken from the WorldWideWEB Consortium, an international multicenter cohort including patients treated with the WEB device. Aneurysms were classified into two groups based on treatment: stent-assisted WEB and WEB device alone. The authors compared clinical and radiological outcomes of both groups. Univariable and multivariable binary logistic regression analyses were performed to determine factors that predispose to stent use. RESULTS The study included 691 intracranial aneurysms (31 with stents and 660 without stents) treated with the WEB device. The adequate occlusion status did not differ between the two groups at the latest follow-up (83.3% vs 85.6%, p = 0.915). Patients who underwent stenting had more thromboembolic (32.3% vs 6.5%, p < 0.001) and procedural (16.1% vs 3.0%, p < 0.001) complications. Aneurysms treated with a concomitant stent had wider necks, greater heights, and lower dome-to-neck ratios. Increasing neck size was the only significant predictor for stent use. CONCLUSIONS This study demonstrates that there is no difference in the degree of aneurysm occlusion between the two groups; however, complications were more frequent in the stent group. In addition, a wider aneurysm neck predisposes to stent assistance in WEB-treated aneurysms.
Intrasaccular flow disruption for ruptured aneurysms: an international multicenter study

Journal of NeuroInterventional Surgery | July 22, 2022 | Volume: 15 | Issue: 9 | Pages: 844-850

10.1136/jnis-2022-019153 | PMID 35868856

Background The Woven EndoBridge (WEB) device is a novel intrasaccular flow disruptor tailored for bifurcation aneurysms. We aim to describe the degree of aneurysm occlusion at the latest follow-up, and the rate of complications of aneurysms treated with the WEB device stratified according to rupture status. Methods Our data were taken from the WorldWideWeb Consortium, an international multicenter cohort including patients treated with the WEB device. Aneurysms were classified into two groups: ruptured and unruptured. We compared clinical and radiologic outcomes of both groups. Propensity score matching (PSM) was done to match according to age, gender, bifurcation, location, prior treatment, neck, height, dome width, daughter sac, incorporated branch, pretreatment antiplatelets, and last imaging follow-up. Results The study included 676 patients with 691 intracranial aneurysms (529 unruptured and 162 ruptured) treated with the WEB device. The PSM analysis had 55 pairs. In both the unmatched (85.8% vs 84.3%, p=0.692) and matched (94.4% vs 83.3%, p=0.066) cohorts there was no significant difference in the adequate occlusion rate at the last follow-up. Likewise, there were no significant differences in both ischemic and hemorrhagic complications between the two groups. There was no documented aneurysm rebleeding after WEB device implantation. Conclusion There was no significant difference in both the radiologic outcomes and complications between unruptured and ruptured aneurysms. Our findings support the feasibility of treatment of ruptured aneurysms with the WEB device.
Prevalence of Intracranial Aneurysms in Patients with Infrarenal Abdominal Aortic Aneurysms: A Multicenter Experience

International Journal of Angiology | June 27, 2020 | Volume: 29 | Issue: 04 | Pages: 229-236

10.1055/s-0040-1713139 | PMID 33268973

AbstractPrior studies suggest high prevalence of intracranial aneurysms (IA) in patients with infrarenal abdominal aortic aneurysms (AAA). We reviewed our multicenter experience in clinical detection/treatment of IAs in AAA patients and estimated the risk of IA in patients with AAA relative to patients without AAA. We reviewed cases of vascular surgery infrarenal AAA repairs at three Mayo Clinic sites from January 1998 to December 2018. Concurrent controls were randomly matched in a 1:1 ratio by age, sex, smoking history, and head imaging characteristics. Conditional logistic regression was used to calculate odds ratios. We reviewed 2,300 infrarenal AAA repairs. Mean size of AAA at repair was 56.9 ± 11.4 mm; mean age at repair, 75.8 ± 8.0 years. 87.5% of the cases (n = 2014) were men. Head imaging was available in 421 patients. Thirty-seven patients were found to have 45 IAs for a prevalence of 8.8%. Mean size of IA was 4.6 ± 3.5 mm; mean age at IA detection, 72.0 ± 10.8 years. Thirty (81%) out of 37 patients were men. Six patients underwent treatment for IA: four for ruptured IAs and two for unruptured IAs. All were diagnosed before AAA repair. Treatment included five clippings and one coil-assisted stenting. Time from IA diagnosis to AAA repair was 16.4 ± 11.0 years. Two of these patients presented with ruptured AAA, one with successful repair and a second one that resulted in death. Odds of IA were higher for patients with AAA versus those without AAA (8.8% [37/421] vs. 3.1% [13/421]; OR 3.18; 95% confidence interval, 1.62–6.27, p < 0.001). Co-prevalence of IA among patients with AAA was 8.8% and is more than three times the rate seen in patients without AAA. All IAs were diagnosed prior to AAA repair. Surveillance for AAA after IA treatment could have prevented two AAA ruptures and one death.