Fritz Wodarg

BACKGROUND AND OBJECTIVES: The Woven Endobridge (WEB) and the Contour Neurovascular System (Contour) are both intrasaccular devices used to treat cerebral aneurysms. We compared outcomes of these 2 devices using data from 2 large registries. METHODS: Data were sourced from the WorldWideWEB Consortium, which included 1363 cases treated with WEB from 2017, and a registry of 277 Contour cases from 10 European centers starting the same year. Patient demographics, aneurysm characteristics, procedural specifics, and outcomes were analyzed. Propensity score matching was applied for comparison. RESULTS: Before matching, the Contour group had more men (37.9% vs 30.8%), more asymptomatic cases (83.4% vs 70.3%), and fewer acute subarachnoid hemorrhage cases (10.8% vs 26.2%). After matching, no significant differences were found in demographics or aneurysm characteristics between groups. The median age was 60 years, and median aneurysm dimensions were comparable. Logistic regression showed no significant differences between WEB and Contour in achieving complete occlusion (odds ratio [OR] = 1.01, 95% CI, 0.67-1.52, P = .971), adequate occlusion (OR = 0.85, 95% CI, 0.41-1.76, P = .665), or achieving modified Rankin Scale 0 to 2 at last follow-up (OR = 0.48, 95% CI, 0.21-1.02, P = .064). Retreatment (OR = 2.23, P = .086), thromboembolic complications (OR = 0.75, P = .452), and adjunctive treatment use (OR = 1.93, P = .141) were also similar. CONCLUSION: The WEB and Contour demonstrated comparable clinical and angiographic outcomes in this large multicenter study comprised majority small, asymptomatic cerebral aneurysms.

Background: Balloon guide catheters (BGCs) are used during mechanical thrombectomy to arrest or reverse blood flow in order to improve revascularization results. Objective: STRAIT was an early post-market study of the new generation BOBBY BGC to evaluate performance and safety in the treatment of anterior circulation large vessel occlusion (LVO). Methods: This prospective, core lab-controlled multicenter study was conducted across nine sites in Germany and Switzerland. Key inclusion criteria were LVO at the distal internal carotid article through proximal M2, symptom onset to treatment initiation within 8 hours, National Institute of Health Stroke Scale (NIHSS) ≥5, and Alberta Stroke Program Early CT Score (ASPECTS) ≥6. Results: After having reached the primary endpoint in the planned interim analysis, enrollment was stopped early. Therefore, STRAIT enrolled 171 subjects from April 2022 to September 2023. Included patients were 49.7% female, median age was 73 years, and median NIHSS was 15. The primary endpoint of successful final reperfusion, as defined by Thrombolysis In Cerebral Infarction (TICI) 2b-3, was achieved in 94.7% of cases (n=161), and modified first pass effect (FPE) was 63.1%, with a median procedure time of 51 min. There were no device malfunction-related serious adverse events or adverse events. At final follow-up, 107/171 subjects (65.2%) had good neurological function (modified Rankin Scale ≤2) and an overall mortality of 8.5%. Conclusion: Mechanical thrombectomy using BOBBY BGC demonstrates high rates of FPE and overall success with a good safety profile, further supporting the additional benefit of the new generation BGCs in interventional stroke treatment. Trial registration number: NCT05361187 .

Objective: In this study, we report our experience with the occurrence of diffusion-weighted imaging (DWI) lesions following aneurysm treatment with Woven EndoBridge (WEB) device and Contour Neurovascular System in elective settings. We compared both techniques in a retrospective single-center analysis, to investigate whether there are significant differences in the incidence of microemboli depending on the device used. Materials and methods: Sixty-two cases treated with Contour were retrospectively compared with 84 WEB cases. Postinterventional MRI was performed in all patients within five days after the angiographic procedure. Only DWI lesions in the dependent vascular territory of the treated aneurysm were considered. Data on occurrence of DWI lesions, device implantation times as well as device change or repositions maneuvers were compared. Results: A total of 146 patients were included in this study. Postinterventional DWI lesions were detected in 33 of the 62 (53.2%) Contour cases and in 36 of the 84 (42.8%) WEB cases with an average lesion number of 1.70 ± 3.45 in our WEB group and 1.68 ± 2.53 in our Contour cohort. Neither periinterventional device changes nor device reposition maneuvers had a significant impact on the occurrence of DWI lesions. Although four patients experienced transient neurological deterioration, the DWI lesions were not clinically relevant at the time of discharge, as the patients’ NIHSS remained stable compared to the preintervention NIHSS in the entire cohort. There was no statistically significant difference between the implantation times of WEB and Contour, although Contour could be implanted slightly faster. Conclusion: Aneurysm treatment with WEB or Contour results in a comparable numbers of procedure-related DWI lesions. This effect was consistent after adjustment for other demographic or technical variables.

Purpose: The contour neurovascular system (CNS) is an intrasaccular flow-disrupting device designed for the treatment of intracranial wide-necked bifurcation aneurysms. Metal artifacts limit magnetic resonance imaging (MRI) accessibility after implantation. The purpose of this in vitro study was to evaluate non-invasive imaging alternatives to digital subtraction angiography (DSA). Material and methods: Three aneurysms of patients originally treated with CNS were three-dimensional (3D)-printed (one at the basilar tip and two at the middle cerebral artery bifurcation). CNS devices were implanted under fluoroscopic control into the 3D models. Post-implantation two-dimensional-DSA, flat panel computed tomography angiography (CTA), MRI, and spectral CTA were performed. Results: Time of flight angiography and T1 weighted sequences showed large susceptibility artifacts at the detachment zone of the devices. A thin-sliced T2 weighted sequence in cross-sectional orientation to the aneurysm allowed visualization of the aneurysm dome, but the aneurysm neck and parent vessel could not be assessed. Focused spectral CTA, especially a 40 keV reconstruction with a metal artifact reduction algorithm (orthopedic metal artifact reduction (OMAR)), showed only minor artifacts at the detachment zone. This approach achieved a very similar result to DSA and flat panel computed tomography, enabling the assessment of the device structure, aneurysm perfusion, and parent vessel perfusion. Discussion and conclusion: For non-invasive follow-up of CNS, focused 40 keV CTA with OMAR seems to be a valuable option. MRI can be valuable for larger aneurysms to assess the aneurysm dome, but was not suitable for evaluating the parent vessels and aneurysm neck after CNS implantation in this study.

Background and purpose: Mechanical thrombectomy (MT) for acute ischemic stroke (AIS) relies on efficient tracking of aspiration catheters through complex vascular anatomies. Differences in catheter design lead to variation in tracking performance which may only become apparent after use in patients. We developed an in-vitro methodology for evaluating aspiration catheter performance under a variety of pre-defined circumstances, that can be used during catheter development for design optimization. Methods: Validation of the in-vitro methodology involved testing four large bore aspiration catheters on recreated challenging vascular access routes derived from patient angiograms. Two experienced neurointerventionalists conducted the tests under controlled physiological and procedural conditions. Each catheter design was evaluated across 30 unique anatomy-procedural set-up combinations. A fifth, prototype large bore catheter was evaluated by trained engineers to assess the applicability of the in-vitro test. Results: Results from statistical analysis using a general linear model demonstrated the methodology's effectiveness in detecting significant tracking differences among catheter designs ( p < 0.01). Minimal inter-operator variability was observed ( p = 0.304), while procedural techniques significantly influenced tracking performance ( p < 0.01). The tortuosity of the arterial access route notably impacted catheter performance ( p < 0.01), with anatomical features revealing varying degrees of influence on desirable and undesirable catheter design aspects. Conclusion: We successfully developed a test methodology for evaluating the trackability of large bore aspiration catheters intended for treating acute ischemic stroke with large vessel occlusions. This methodology offers a robust approach to pre-clinical design assessment, utilizing anatomical models that simulate real-world vascular challenges to enhance catheter optimization.

Background The Woven EndoBridge (WEB) device is designed to treat wide-necked bifurcation aneurysms. The WEB 17 is the latest iteration and can be delivered through a 0.017″ microcatheter. The CLEVER study demonstrated that WEB 17 is safe and effective for providing protection against bleeding or rebleeding at 1 month and 1 year. Objective To evaluate angiographic stability at 1 year. Methods The CLEVER study was a prospective multicenter study conducted in 17 European centers, involved 163 subjects, comprising 60 ruptured and 103 unruptured aneurysms. Independent assessment of 1-year follow-up imaging was incorporated into the study design. Results Aneurysm diameters ranged from 2.0 to 9.2 mm, with 95.7% being broad-based (dome-to-neck ratio Conclusion Delivery of the WEB 17 via 0.017 inch catheters represents a significant evolution of the WEB design. The results of CLEVER presented here demonstrate that it maintains the same efficacy as previous generations of WEB.

Background Intrasaccular devices have become increasingly popular in the treatment of cerebral aneurysms, particularly at the bifurcation. Here we evaluate the Contour Neurovascular System, an intrasaccular device for the endovascular treatment of cerebral aneurysms, in a multicenter cohort study, the largest to the best of our knowledge. Methods Consecutive patients with intracranial aneurysms treated with the Contour Neurovascular System between February 2017 and October 2022 at 10 European neurovascular centers were prospectively collected and retrospectively reviewed. Patient and aneurysm characteristics, procedural details, and angiographic and clinical outcomes were evaluated. Results During the study period, 279 aneurysms (median age of patients 60 years, IQR 52–68) were treated with Contour. In 83.2% of patients the device was placed electively, whereas the remaining patients were treated in the setting of acute subarachnoid hemorrhage. The most common locations were the middle cerebral artery (26.5%) followed by the anterior communicating region (26.2%). Median aneurysm dome and neck size were 5.2 mm (IQR 4.2–7) and 3.9 mm (IQR 3–5). Contour size 7 (39%) and 9 (25%) were most used. Thromboembolic and hemorrhagic complications occurred in 6.8% and 0.4% of aneurysms, respectively. Raymond-Roy 1 and 2 occlusions at last follow-up were achieved in 63.2% and 28.3%, respectively, resulting in adequate occlusion of 91.5% of aneurysms. Conclusion This is the largest multicenter study reporting the outcome on the Contour Neurovascular System. At 1 year, the self-evaluated data on safety and efficacy are comparable to data of existing intrasaccular devices. Contour is a promising technology in the treatment of cerebral aneurysms.

Introduction: Treatment of basilar apex aneurysms will remain challenging regarding the nobility of the parent vessel and their often wide-necked configuration. With endovascular techniques being the treatment approach of choice, novel intrasaccular flow-disruption devices constitute an endovascular embolization option. In this research, we report our experiences in embolizing basilar tip aneurysms with the novel Contour device. Material and methods: Retrospective analysis of eight patients after Contour implantation into a basilar apex aneurysm. Periprocedural data on intervention times, radiation dose, procedural success and complications were gathered. All patients received follow-up digital subtraction angiography after six months. Further follow-up examination results were analysed given their availability. Results: Contour implantation was successful in all patients. The mean device instrumentation time was 18.8 ± 7.7 min with a mean full intervention time of 100 ± 65.8 min. The mean full procedure radiation dose was 1917 (421–5107) cGy/cm ² . After six months, six aneurysms were occluded (Raymond Roy Scale (RRS) 1/2), one showed perfusion inside the device (RRS 3a) and one patient had undergone reintervention due to progression. The aneurysm with constant perfusion at six months was seen to be occluded after 24 months. Conclusion: Contour device implantation is a promising feasible alternative endovascular method for embolization of intracranial aneurysms located in the basilar tip with short intervention times and low radiation dosages. Short- and medium-term follow-ups show promising results concerning aneurysm occlusion and reinterventions, however further research is needed to show long-term stability.

Background Intrasaccular flow disruption is an endovascular approach for the treatment of wide-neck aneurysms and, more specifically, wide-neck bifurcation aneurysms, which are challenging to treat with previously developed technologies. The Woven EndoBridge (WEB) device has demonstrated its efficacy and safety, for both unruptured and ruptured aneurysms. Methods The CLEVER study was an observational, multicenter, prospective study conducted in 17 European investigational sites using the WEB 17 device, for the treatment of ruptured and unruptured aneurysms. The study objective was to provide safety and efficacy data on the WEB 17 device in the treatment of wide-neck bifurcation aneurysms. Imaging results were assessed independently by a Corelab and adverse events adjudicated by a Clinical Event Adjudicator. This analysis reports procedural results and safety at 30 days and 12 months. Results A total of 163 patients (mean age 58.1 years; 68.1% women) with 103 unruptured aneurysms and 60 ruptured aneurysms were enrolled. Most aneurysms were located on the anterior communicating artery (ACom) (37.4%) or the middle cerebral artery (MCA) bifurcation (30.1%). Aneurysm widths ranged from 2.0–9.2 mm, and the mean sac width was 5.0 mm. The WEB procedure was successfully completed in 163 patients (100%). At the 12-month follow-up, major stroke events occurred in 3 of 163 patients (1.8%), and no device-related mortality was observed. Conclusion Endovascular treatment of ruptured and unruptured wide-neck bifurcation aneurysms using WEB 17 is safe, with a low complication rate and no device-related mortality. In particular, none of the ruptured aneurysms bled again up to 1 year of follow-up. Trial registration number NCT03844334.