Shoji Matsumoto

PURPOSE: The Woven EndoBridge (WEB) was introduced in Japan in January 2021 and approved for all subtypes of wide-neck bifurcation aneurysms (WNBA). This retrospective study evaluated the safety and efficacy of the WEB device for all subtypes of WNBA. MATERIALS AND METHODS: All patients treated with the WEB at our facility between January 2021 and May 2024 was reviewed. We selected the WEB device according to an oversizing policy, based on cumulative clinical evidence from global experience. RESULTS: We analyzed 120 aneurysms in 117 patients (56 males and 61 females with a mean age of 65.5±12.7 years). There were 45 anterior communicating artery aneurysms, 27 middle cerebral artery aneurysms, 17 internal carotid artery-posterior communicating artery aneurysms, 15 basilar artery top aneurysms, and 16 aneurysms in other locations. Aneurysm characteristics included a maximum diameter of 6.5 [5.3, 7.7] mm, height of 4.9 [3.9, 6.0] mm, width of 4.8 [4.0, 6.2] mm, and dome/neck ratio of 1.2 [1.1, 1.4]. All data are expressed in median [interquartile range]. Angiographic follow-up at 12 months in 96 cases showed complete obliteration in 68.8% and adequate obliteration in 90.6% of cases. Intraoperative ischemic events occurred in 5 cases (4.2%). Hemorrhagic events occurred in 2 cases (1.7%), with symptoms resolving by discharge, except for 1 case of mild paralysis. During follow-up, 1 patient developed a major stroke, resulting in morbidity (0.8%). Retreatment was required in 3 cases (2.5%). On multivariate analysis for complete occlusion at 12 months following WEB treatment, age was statistically associated with the outcome (odds ratio, 0.957 per year; 95% confidence interval, 0.919-0.996; P=0.033). CONCLUSION: WEB is safe and effective for all subtypes of WNBA, with a low retreatment rate using an oversizing policy. This is the first report in a Japanese population.

Purpose Digital subtraction angiography (DSA) is the gold standard for follow-up evaluation of intracranial aneurysms treated with the Woven EndoBridge (WEB) device. This study aimed to assess the efficacy of high-resolution CT angiography (HR-CTA) as a less invasive alternative by comparing its diagnostic performance with that of DSA. Methods This single-center retrospective study analyzed the angiographic and clinical data of patients treated with the WEB device for cerebral aneurysms between January 2021 and December 2024. Patients who underwent HR-CTA within 2 weeks before or after follow-up DSA were included. Occlusion status was assessed using the Bicêtre Occlusion Scale Score (BOSS) and binary classification. The concordance rate between HR-CTA and DSA was evaluated. Results A total of 54 eligible examinations were identified. Using the BOSS, 46 examinations were concordant, resulting in an agreement rate of 85.2%. The Cohen’s κ coefficient was 0.81 (95% CI 0.69 to 0.93), indicating a very high level of agreement. All discordant cases resulted from HR-CTA overestimating occlusion status; however, HR-CTA accurately identified aneurysm remnants. Univariate analyses identified BOSS 0’ as the only significant factor contributing to discrepancies. In the binary evaluation, all 54 examinations were fully concordant (κ=1.00, 95% CI 1.00 to 1.00). Conclusions HR-CTA demonstrated a high concordance rate with DSA for evaluating occlusion status after WEB placement. Its reliable assessment of aneurysm remnants suggests HR-CTA could serve as a practical and less invasive alternative to DSA in follow-up evaluations.

BACKGROUND: This study aimed to determine the efficacy of flow diverters (FDs) for small/medium (≤10 mm) aneurysms and analyzed the factors that prevent aneurysm occlusion. METHODS: This retrospective single-center study evaluated the angiographic and clinical data of consecutive patients between June 2020 and February 2023. RESULTS: Overall, 121 small/medium aneurysms were observed in 106 patients treated with FDs. The median dome diameter was 6.1 (5.1-7.2) mm. Symptomatic thromboembolic complications were observed in four (3.7 %) patients, and none showed a major ischemic stroke. Intracranial hemorrhage was detected using postprocedural computed tomography in one (0.9 %) patient with asymptomatic subarachnoid hemorrhage. The rate of permanent neurological deficits was 1.8 %, and the mortality rate was 0 %. No delayed ischemic or hemorrhagic complications were observed during follow-up. Angiographic follow-up revealed complete and adequate occlusion (O'Kelly-Marotta grades C and D) rates of 77.5 % and 90.8 %, respectively. On multivariate analysis, incomplete occlusion was only associated with the presence of a branch vessel from the aneurysm dome (P < 0.01). In aneurysms with incorporated branch vessels, univariate analysis revealed that coil usage was a predictor of complete occlusion (P = 0.03). Moreover, even without using coils, effective occlusion was achieved when the branch vessel diameter was small (P = 0.03). CONCLUSIONS: FDs are an effective and safe treatment option for small/medium aneurysms. The presence of incorporated branch vessels can predict incomplete occlusion. Even in aneurysms with incorporated branch vessels, FD can obtain therapeutic effects by adding coil embolization or treating with only FD if the branch vessel diameter is small.

We report a case in which a novel distal access catheter proved successful in the placement of a flow diverter for a challenging distal cerebral artery lesion. We discuss the advantages and pitfalls of this technique and considerations for its use. A 74-year-old female presented with intermittent headaches, and was diagnosed with a dissecting aneurysm at the proximal right posterior cerebral artery with a sharp bleb, measuring 9.8 mm in diameter. Given the complex vascular anatomy, stent-assisted coil embolization was initially considered but deemed high risk for dual catheter for jailing technique with 6-Fr size guiding catheter due to the tortuosity and stenosis of the parent vessel. Therefore, we opted for flow diverter treatment, which presented its challenges during delivery. By employing a low-profile distal access catheter, Phenom Plus (outer diameter: 4.2-Fr. inner diameter: 1.13 mm; Medtronic, Minneapolis, Minnesota, United States), with a minimal ledge between it and the delivery catheter, Phenom 27 (outer diameter: 2.8-Fr, 0.91 mm; Medtronic), we successfully crossed the neck of the aneurysm with Phenom Plus and placed the flow diverter. While acknowledging potential risks, this case demonstrates the value of the neck-crossing technique using a low-profile distal access catheter as an alternative option for treating challenging peripheral artery aneurysms with flow diverters. This technique offers promise in specific situations where conventional methods pose challenges.