First-in-human, real-time artificial intelligence assisted cerebral aneurysm coiling: a preliminary experience

BACKGROUND

Neuroendovascular procedures require careful and simultaneous attention to multiple devices on multiple screens. Overlooking unintended device movements can result in complications. Advancements in artificial intelligence (AI) have enabled real-time notifications of device movements during procedures. We report our preliminary experience with real-time AI-assisted cerebral aneurysm coiling in humans.

METHODS

A real-time AI-assistance software (Neuro-Vascular Assist, iMed technologies, Tokyo, Japan) was used during coil embolization procedures in nine patients with an unruptured aneurysm. The AI system provided real-time notifications for 'coil marker approaching', 'guidewire movement', and 'device entry' on biplane fluoroscopic images. The efficacy, accuracy, and safety of the notifications were evaluated using video recordings.

RESULTS

The AI system functioned properly in all cases. The mean number of notifications for coil marker approaching, guidewire movement, and device entry per procedure was 20.0, 3.0, and 18.3, respectively. The overall precision and recall were 92.7% and 97.2%, respectively. Five of 26 true positive guidewire notifications (19%) resulted in adjustment of the guidewire back toward its original position, indicating the potential effectiveness of the AI system. No adverse events occurred.

CONCLUSIONS

The software was sufficiently accurate and safe in this preliminary study, suggesting its potential usefulness. To the best of our knowledge, this is the first reported use of a real-time AI system for assisting cerebral aneurysm coiling in humans. Large scale studies are warranted to validate its effectiveness. Real-time AI assistance has significant potential for future neuroendovascular therapy.

Enhancing thromboresistance of neurovascular nickel-titanium devices with responsive heparin hydrogel coatings

BACKGROUND

Neurointerventional devices, particularly laser-cut thin-strut stents made of self-expanding nickel-titanium alloy, are increasingly utilized for endovascular applications in intracranial arteries and dural venous sinuses. Preventing thrombosis and stroke necessitates systemic anticoagulant and antiplatelet therapies with the risk of bleeding complications. Antithrombotic coatings present a promising solution.

METHODS

In this study, we investigated the potential of hydrogels composed of four-armed poly(ethylene glycol) (starPEG) and heparin, with or without coagulation-responsive heparin release, as coatings for neurovascular devices to mitigate blood clot formation. We evaluated the feasibility and efficacy of these coatings on neurovascular devices through in vitro Chandler-Loop assays and implantation experiments in the supra-aortic arteries of rabbits.

RESULTS

Stable and coagulation-responsive starPEG-heparin hydrogel coatings exhibited antithrombotic efficacy in vitro, although with a slightly reduced thromboprotection observed in vivo. Furthermore, the hydrogel coatings demonstrated robustness against shear forces encountered during deployment and elicited only marginal humoral and cellular inflammatory responses compared with the reference standards.

CONCLUSION

Heparin hydrogel coatings offer promising benefits for enhancing the hemocompatibility of neurointerventional devices made of self-expanding nickel-titanium alloy. The variance in performance between in vitro and in vivo settings may be attributed to differences in low- and high-shear blood flow conditions inherent to these models. These models may represent the differences in venous and arterial systems. Further optimization is warranted to tailor the hydrogel coatings for improved efficacy in arterial applications.

Mid-term safety and efficacy in small intracranial aneurysm coiling: results from TARGET® nano prospective independent core lab adjudicated multicenter registry

Background

The primary objective is to evaluate the safety and effectiveness of Stryker second generation Target® Nano Coils in the treatment of ruptured and unruptured small (<7 mm) intracranial aneurysms.

Methods

The TARGET Registry is a prospective, two-arm study with independent medical event monitoring and core-lab adjudication. This paper describes the second arm of the TARGET registry. Patients with de novo intracranial aneurysms were embolized with 2nd generation TARGET Nano coils in 12 US centers. The primary efficacy outcome was adequate aneurysm occlusion (RR occlusion grade I-II) on follow-up. Primary safety outcome was treatment-related morbidity and mortality. Secondary outcomes included aneurysm packing density immediately post-procedure, immediate adequate occlusion, aneurysm re-access rate, retreatment rate and clinical outcomes using modified ranking scale. A secondary analysis investigated the influence of using Nano-predominant coils (≥2/3 of total coil-length) vs. non-Nano-predominant coils (<2/3 of total length).

Results

150 patients with 155 aneurysms met the inclusion and exclusion criteria. (31%) patients with ruptured and (69%) with unruptured aneurysms were treated using TARGET coils. Median age was 58.8 (SD 12.7), 74.7% were females, and 80% were Caucasians. Mean follow-up was 5.23 (SD 2.27) months. Peri-procedural mortality was seen in 2.0% of patients. Good outcome at discharge (mRS 0-2) was seen in 81.3% of the cohort. The median packing density (SD) was 29.4% (14.9). Mid-term complete/near complete occlusion rate was seen in 96% of aneurysms and complete obliteration was seen in 75.2% of aneurysms. Patients treated predominantly with Nano coils had higher PD (32.6% vs. 26.1%, p < 0.001). There was no significant difference in clinical and angiographic outcomes. The mid-term mRS0-2 was achieved in 106/109 (97.2%) patients. All-cause mortality was 5/115 (4.3%).

Conclusion

In the multicenter TARGET Registry, 75.8% of aneurysms achieved mid-term complete occlusion, and 96% achieved complete/near complete occlusion with excellent independent functional outcome.

Initial Experiences with the Trenza Embolization Device for the Treatment of Wide-Neck Intracranial Aneurysms: A 12-Patient Case Series

The Trenza embolization device is a frame coil implant with flow-disruption properties and is a new alternative to treat challenging mid-to-large-sized broad-neck bifurcation or sidewall aneurysms. We conducted an observational single-center retrospective study of 12 consecutive patients treated for 10 unruptured and 2 ruptured 6- to 12-mm broad-neck bifurcation or sidewall aneurysms with the Trenza device during 2022-2023. The median patient age was 64 years (interquartile range, 59-70 years), 58% were women, the median largest aneurysm diameter was 9.6 mm (interquartile range, 7.5-11.9 mm), the median dome-to-neck ratio was 1.8 (interquartile range, 1.6-1.9), the most common aneurysm locations were the anterior communicating artery (33%) and basilar artery tip (33%). After a median follow-up of 6.5 months, adequate aneurysm occlusion was achieved in 83%. There were 3 major ischemic complications (25%), leading to 2 permanent neurologic deficits (17%) and 1 transient neurologic deficit (8%). There was 1 fatal rupture of a treated aneurysm 1.6 months after the index treatment. Two patients were retreated (17%). Ischemic complications occurred in patients after a too-dense coil packing at the base of the aneurysm. No technical issues related to the device were encountered. In summary, an adequate aneurysm occlusion rate was achieved using the Trenza-assisted coiling technique for otherwise challenging mid-to-large-sized broad-neck aneurysms. Ischemic complications seemed to occur following overdense coiling at the base of the aneurysm.

Clinical and angiographic characteristics of ruptured and unruptured distal cerebral aneurysms: a review of a large series of cases in a high-volume center

OBJECTIVE

To evaluate clinical, angiographic features, and endovascular approach of ruptured and unruptured distal intracranial aneurysms (DIAs).

METHODS

From January 2013 to February 2022, details of all consecutive intracranial aneurysms (IAs) treated endovascularly in our center were collected and retrospectively reviewed. IAs involving the anterior cerebral artery, middle cerebral artery, and posterior cerebral artery (distal to anterior communicating artery, limen insula, and P1 segment, respectively), and those distal to superior cerebellar artery, anterior-inferior cerebellar artery, and posterior inferior cerebellar artery's first segment were classified based on their etiology, location, size, and shape. Demographic, clinical, angiographic, and procedural variables, as well as follow-up outcomes were evaluated.

RESULTS

Of 2542 IAs, 151 (5.9%) DIAs were counted (average size 5.4±2.9 mm), including 61 (40.4%) unruptured and 90 (59.6%) ruptured. No difference in the aneurysmal size was observed, but aneurysms smaller than 4 mm were observed more frequently in the ruptured group (36.7% vs 18%; P=0.01). In addition, ruptured DIAs were more often non-saccular (40% vs 18%; P=0.004) and irregular (93.3% vs 59%; P<0.001), They were treated mostly by coiling, glue, and parent artery sacrifice (P=0.02, P=0.006, and P=0.001), whereas unruptured DIAs were treated by stent-assisted coiling and flow-diverter stents (P=0.001 and P<0.001, respectively), without any differences in occlusion (81.6% vs 82.5%) and recanalization (21.1% vs 17.5%) rates. Procedure-related complications occurred in 20/151 (13.2%) patients, without any differences between subgroups. Ruptured DIAs were more often re-treated (18.4% vs 5.3%, P=0.02). In multivariate analyses, irregular shape appeared as an independent predictor of ruptured presentation (OR=8.1, 95% CI 3.0 to 21.7; P<0.001).

CONCLUSIONS

Compared with unruptured DIAs, ruptured DIAs were more often non-saccular, irregular, and smaller than 4 mm. Despite different therapeutical approaches, ruptured and unruptured DIAs presented comparable occlusion and recanalization rates.

Endovascular Treatment of Small Anterior Communicating Artery Aneurysms: Safety and Efficacy in a Contemporary Cohort

BACKGROUND AND OBJECTIVES

Endovascular treatment (EVT) of small anterior communicating artery (ACoA) aneurysms accompanies a high risk of intraprocedural rupture (IR) because of anatomic location and aneurysm orientation. In this study, we aimed to investigate the safety and efficacy of EVT for small ACoA aneurysms in a contemporary cohort.

METHODS

ACoA aneurysms treated at the Medical University of South Carolina between April 2012 and March 2022 were retrospectively analyzed. Periprocedural baseline characteristics, aneurysm size, and clinical and radiological outcomes were collected. Aneurysms were dichotomized into <4 and ≥4 mm in maximum size. The IR rate, favorable occlusion rate (Raymond-Roy I and II), and the favorable outcome defined as modified Rankin Scale 0-2 were compared.

RESULTS

A total of 174 patients were identified, of whom 111 (63.8%) were female, and the median age was 57.7 (interquartile range 50.6-69.6) years. 98 (56.3%) aneurysms were ruptured, and 53 (30.5%) were <4 mm. IR was not observed in unruptured ACoA aneurysms, and there was no significant difference in the IR rates between <4 mm and ≥4 mm ruptured aneurysms (6.5% vs 4.5%, P = .65). Favorable occlusion rate and favorable outcome were observed in 94.7% and 78.2% of patients, respectively.

CONCLUSION

EVT of small ACoA aneurysms is safe and effective.

Woven EndoBridge Device for Unruptured Wide-Neck Bifurcation Aneurysm: A Multicenter 5-Year Follow-up

BACKGROUND AND OBJECTIVES

This multicenter study aimed to assess the safety and efficacy of the Woven EndoBridge (WEB) device for treating unruptured wide-neck intracranial bifurcation aneurysms (WIBAs) with short-, mid-, and long-term follow-ups (FUPs).

METHODS

Consecutive patients with unruptured WIBAs treated with WEB between December 2014 and January 2018 were included. Patient, aneurysm, and device characteristics were collected and analyzed retrospectively. Morbidity and mortality rates were determined by collecting intraprocedural, periprocedural, and delayed complications. Aneurysm occlusion was assessed at 1, 3, and 5 years using a 3-grade scale: complete occlusion, neck remnant, and residual aneurysm. Complete occlusion and neck remnant were considered as adequate occlusion. Patients who received re-treatment were also evaluated.

RESULTS

The study included 104 consecutive patients (55.8% female, mean age 58.6 ± 11.8 years). Aneurysm maximum size, neck, and dome-to-neck mean were, respectively, 6.9 ± 2.1 mm, 4.5 ± 1.2 mm, and 1.4 ± 0.3 mm. One-year FUP was collected for 95 patients, and 3- and 5-year FUPs were collected for 83 patients. Adequate occlusion was observed at 1-year FUP in 90.5% (86/95), 91.6% (76/83) was observed at 3-year FUP, and 92.8% (77/83) at 5-year FUP. None of the aneurysms bled after treatment. During FUP, 6/83 patients (7.2%) were re-treated for residual aneurysm. Morbidity and mortality rates closely related to aneurysm occlusion were 0% (0/104).

CONCLUSION

The WEB device was safe and effective for treating unruptured WIBAs, both in short-term and long-term FUPs.

Adverse events during endovascular treatment of ruptured aneurysms: A prospective nationwide study on subarachnoid hemorrhage in Sweden

Introduction

A range of adverse events (AEs) may occur in patients with subarachnoid hemorrhage (SAH). Endovascular treatment is commonly used to prevent aneurysm re-rupture.

Research question

The aim of this study was to identify AEs related to endovascular treatment, analyze risk factors for AEs and how AEs affect patient outcome.

Material and methods

Patients with aneurysmal SAH admitted to all neurosurgical centers in Sweden during a 3.5-year period (2014-2018) were prospectively registered. AEs related to endovascular aneurysm treatment were thromboembolic events, aneurysm re-rupture, vessel dissection and puncture site hematoma. Potential risk factors for the AEs were analyzed using multivariate logistic regression. Functional outcome was assessed at one year using the extended Glasgow outcome scale.

Results

In total, 1037 patients were treated for ruptured aneurysms. Of which, 715 patients were treated with endovascular occlusion. There were 115 AEs reported in 113 patients (16%). Thromboembolic events were noted in 78 patients (11%). Aneurysm re-rupture occurred in 28 (4%), vessel dissection in 4 (0.6%) and puncture site hematoma in 5 (0.7%). Blister type aneurysm, aneurysm smaller than 5 mm and endovascular techniques other than coiling were risk factors for treatment-related AEs. At follow-up, 230 (32%) of the patients had unfavorable outcome. Patients suffering intraprocedural aneurysm re-rupture were more likely to have unfavorable outcome (OR 6.9, 95% CI 2.3-20.9).

Discussion and conclusion

Adverse events related to endovascular occlusion of a ruptured aneurysm were seen in 16% of patients. Aneurysm re-rupture during endovascular treatment was associated with increased risk of unfavorable functional outcome.

Treatment of Ruptured Wide-Necked Aneurysms using a Microcatheter Injectable Biomaterial

Ruptured wide-neck aneurysms (WNAs), especially in a setting of coagulopathy, are associated with significant morbidity and mortality. It is shown that by trapping a sub-millimeter clinical catheter inside the aneurysm sac using a flow diverter stent (FDS), instant hemostasis can be achieved by filling the aneurysm sac using a novel biomaterial, rescuing catastrophic bleeding in large-animal models. Multiple formulations of a biomaterial comprising gelatin, nanoclay (NC), and iohexol are developed, optimized, and extensively tested in vitro to select the lead candidate for further testing in vivo in murine, porcine, and canine models of WNAs, including in a subset with aneurysm rupture. The catheter-injectable and X-ray visible versions of the gel embolic agent (GEA) with the optimized mechanical properties outperform control groups, including a subset that receive a clinically used liquid embolic (Onyx, Medtronic), with and without aneurysm rupture. A combinatorial approach to ruptured WNAs with GEA and FDS may change the standard of medical practice and save lives.

Thromboembolic complications during and after embolization of unruptured aneurysms: A chronological outcome in periprocedural thromboembolic events

Background

Ischemic complications develop after elective coil embolization procedures at a certain rate. The prevention of these events has been a longstanding issue for many interventional neuroradiologists. This study aimed to clarify whether procedural ischemic events after unruptured aneurysm embolization decrease over time with perioperative anti-thromboembolic treatment or surgical experience.

Methods

This study included patients with cerebral aneurysms in our institution between July 2012 and June 2020. Dual-antiplatelet therapy (DAPT) was performed (Phase 1). Thromboembolic events developed at a certain rate; thus, rivaroxaban was administered with single-antiplatelet therapy (SAPT) to improve thromboembolic results (Phase 2), showing better outcomes than in Phase 1. Subsequently, DAPT was administered again (Phase 3). Ischemic complications were evaluated in each phase or compared between the DAPT group and the direct oral anticoagulant (DOAC) with the clopidogrel (DOAC+SAPT) group.

Results

Relatively, fewer symptomatic ischemic events were noted in Phase 2 or the DOAC+SAPT group, but the outcome was not better in Phase 3 than in Phase 2. Symptomatic complications were more common in Phase 3 than in Phases 1 and 2.

Conclusion

Ischemic complications occurred at a certain rate after endovascular procedures for unruptured aneurysms. The incidence did not decrease over time; particularly, standard DAPT plus postoperative anti-thromboembolic medication did not adequately decrease complications in Phase 3 compared to Phases 1 and 2. Therefore, accumulated experience or a learning curve could not explain the results. DOAC administration might decrease the risk of these events, but further accumulation of evidence or prospective investigation is warranted.

Robust critical limb ischemia porcine model involving skeletal muscle necrosis

This work sought to develop a robust and clinically relevant swine model of critical limb ischemia (CLI) involving the onset of ischemic muscle necrosis. CLI carries about 25-40% risk of major amputation with 20% annual mortality. Currently, there is no specific treatment that targets the ischemic myopathy characteristic of CLI. Current swine models of CLI, with tolerable side-effects, fail to achieve sustained ischemia followed by a necrotic myopathic endpoint. Such limitation in experimental model hinders development of effective interventions. CLI was induced unilaterally by ligation-excision of one inch of the common femoral artery (CFA) via infra-inguinal minimal incision in female Yorkshire pigs (n = 5). X-ray arteriography was done pre- and post-CFA transection to validate successful induction of severe ischemia. Weekly assessment of the sequalae of ischemia on limb perfusion, and degree of ischemic myopathy was conducted for 1 month using X-ray arteriography, laser speckle imaging, CTA angiography, femoral artery duplex, high resolution ultrasound and histopathological analysis. The non-invasive tissue analysis of the elastography images showed specific and characteristic pattern of increased muscle stiffness indicative of the fibrotic and necrotic outcome expected with associated total muscle ischemia. The prominent onset of skeletal muscle necrosis was evident upon direct inspection of the affected tissues. Ischemic myopathic changes associated with inflammatory infiltrates and deficient blood vessels were objectively validated. A translational model of severe hindlimb ischemia causing ischemic myopathy was successfully established adopting an approach that enables long-term survival studies in compliance with regulatory requirements pertaining to animal welfare.

The Woven EndoBridge for intracranial aneurysms: Radiological outcomes and factors influencing occlusions at 6 and 24 months

PURPOSE

To identify factors influencing short- and mid-term radiological outcomes of intracranial aneurysms (IAs) treated with the Woven EndoBridge (WEB).

METHODS

A total of 112 patients were treated for IAs with the WEB in at our institution between 2013 and 2020. Patients with 6- and/or 24-months follow-up data were included in the study. Aneurysm occlusion was evaluated using the Raymond-Roy occlusion classification (RR). RR 1 and RR 2 were considered as adequate outcomes, while RR 3 inadequate.

RESULTS

Data were available for 91 patients (56 females, 62%) at 6 months and 62 of those patients (39 females, 58%) at 24 months. The adequate occlusion (RR 1/RR 2) rate was 89% (n = 81/91) at the 6-months follow-up and 91% (n = 56/62) at the 24-months follow-up. The treatment-related morbidity rate was 4% (n = 4/91), and mortality rate was 1% (n = 1/91). The predictor for inadequate occlusion at the 6-months follow-up was the lobular shape of an aneurysm (p = .01). The aneurysm's height (p = .02), maximal diameter (p = .001), width (p = .002), aspect ratio (p = .03), dome-to-neck ratio (p = .04), and lobular shape (p= .03) were predictive factors for inadequate occlusion at 24 months. All the thrombosed aneurysms (n = 3) showed unfavorable radiological outcomes and required re-treatment within 24 months. None of the patient-related factors were significant.

CONCLUSIONS

The WEB provides favorable occlusion rates and low complications for both ruptured and unruptured wide-necked IAs. Unfavorable radiological outcomes after WEB treatment may be related to aneurysm morphology and size.

Impact of Very Small Aneurysm Size and Anterior Communicating Segment Location on Outcome after Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Very small anterior communicating artery aneurysms (vsACoA) of <5 mm in size are detected in a considerable number of patients with aneurysmal subarachnoid hemorrhage (aSAH). Single-center studies report that vsACoA harbor particular risks when treated.

OBJECTIVE

To assess the clinical and radiological outcome(s) of patients with aSAH diagnosed with vsACoA after aneurysm treatment and at discharge.

METHODS

Information on n = 1868 patients was collected in the Swiss Subarachnoid Hemorrhage Outcome Study registry between 2009 and 2014. The presence of a new focal neurological deficit at discharge, functional status (modified Rankin scale), mortality rates, and procedural complications (in-hospital rebleeding and presence of a new stroke on computed tomography) was assessed for vsACoA and compared with the results observed for aneurysms in other locations and with diameters of 5 to 25 mm.

RESULTS

This study analyzed n = 1258 patients with aSAH, n = 439 of which had a documented ruptured ACoA. ACoA location was found in 38% (n = 144/384) of all very small ruptured aneurysms. A higher in-hospital bleeding rate was found in vsACoA compared with non-ACoA locations (2.8 vs 2.1%), especially when endovascularly treated (2.1% vs 0.5%). In multivariate analysis, aneurysm size of 5 to 25 mm, and not ACoA location, was an independent risk factor for a new focal neurological deficit and a higher modified Rankin scale at discharge. Neither very small aneurysm size nor ACoA location was associated with higher mortality rates at discharge or the occurrence of a peri-interventional stroke.

CONCLUSION

Very small ruptured ACoA have a higher in-hospital rebleeding rate but are not associated with worse morbidity or mortality.

Assessment of balloon remodeling techniques in endovascular treatment of wide-neck intracranial aneurysms (WN-IAs)

OBJECTIVES

To evaluate the clinical, technical, and angiographic results in endovascular management of wide-neck intracranial aneurysms (WN-IAs) using the balloon-remodeling technique.

METHODS

This study was a prospective, single-center study that was carried out over a period of three years from January 2019 to December 2021 at the Neuro-Interventional Unit at our hospital. Patients who presented with WNIAs and were eligible for endovascular treatment using the balloon-remodeling approach were included in the study.

RESULTS

We included 37 patients with a mean age of 49.7 ± 12.3 years. About 91.9% of the participants had SAH, 5.4% had unruptured aneurysms, and 2.7% had intracranial hemorrhage. The mean time to treatment was 6.97 ± 7.35 days, the mean aneurysm diameter was 5.7 ± 1.7 mm, and the mean neck diameter was 3.8 ± 1.0 mm. The majority of the patients had a dom-to-neck ratio of less than 2 (89.2%). We have used hyper form balloons in 48.6%, hyper glide in 43.2%, Copernic balloons in 5.4%, and eclipse in 2.7%. According to the Raymond-Roy occlusion classification, 86.5% of the patients had complete obliteration, 10.8% had residual neck, and 2.7% had a residual aneurysm. Almost 91.9% had no complications, 2.7% had ischemia, and 5.4% had mild rupture by wire, treated by 5 min hyperinflation of the balloon till hemorrhage stopped.

CONCLUSIONS

Balloon-assisted detachable coiling is an important option in the treatment of WN-IAs. We found that this technique allowed safe and efficient treatment of aneurysms when conventional treatment had failed due to WN. Endovascular coiling using the balloon remodeling technique of wide neck showed a high technical success rate and good short-term clinical outcomes. A good selection of patients with WN-IAs treated by endovascular coiling using balloon remodeling technique and a good selection of materials used help in decreasing the complications.

Long term WEB results - still going strong at 5 years?

OBJECTIVE

The aim of our multi-center study is to examine 5-year radiological outcomes of intracranial aneurysms (IAs) treated with the Woven EndoBridge (WEB).

METHODS

All patients treated with WEB between January 2013 and December 2016 were included. Patient and aneurysm characteristic data was collected from the electronic patient record. Aneurysm occlusion was assessed using a 3-grade scale: complete occlusion, neck remnant, and aneurysm remnant. Complete occlusion and neck remnant were considered as adequate occlusion, whereas aneurysm remnant was assessed as an inadequate occlusion.

RESULTS

A total of 66 patients (72.7% female) with 66 IAs (n = 25 acutely ruptured) were treated with WEB. The mean age of patients was 55.6 years (range: 36-71 years). The mean width of the aneurysm neck was 4.5 mm (range: 2-9 mm). 5-year imaging follow-up data was not available for 16.6% patients (n = 11). During the follow up period, 14.5% of IAs (n = 8/55) required retreatment within 24 months of initial treatment with the WEB. A total of 55 IAs were analyzed for 5-year radiological outcome. Of these, including IAs required retreatment, 47.3% of IAs (n = 26/55) were occluded completely, 36.4% (n = 20/55) had neck remnant and 16.3% (n = 9/55) had recanalized. 83.7% of IAs were occluded adequately. None of the IAs rebled after initial treatment with WEB.

CONCLUSION

WEB can provide acceptable adequate occlusion rates at 5 years. Furthermore, recanalization appears to be unlikely after the first two years post-treatment. The results of large studies are needed to confirm these promising long term radiological outcomes.

Three-dimensional printing-assisted precision microcatheter shaping in intracranial aneurysm coiling

Optimal microcatheter shaping is essential for successful endovascular coiling procedures which is sometimes challenging. Our aim was not only to introduce a new shaping method using three-dimensional (3D) printed vessel models but also to prove its feasibility, efficiency and superiority. This was a retrospective cohort study. From September 2019 to March 2021, 32 paraclinoid aneurysms managed with endovascular coiling were retrospectively included and identified. Sixteen aneurysms were coiled using 3D microcatheter shaping method (3D shaping group), and traditional manual shaping method using shaping mandrels was adopted for another 16 patients (control group). The cost and angiographical and clinical outcomes between the two groups were compared, and the feasibility and effectiveness of the new 3D shaping method were evaluated and described in detail. With technical success achieved in 93.75%, most of the 16 shaped microcatheters using new shaping method could be automatically navigated into the target aneurysms without the assistance of microguidewires and could be assessed with favorable accessibility, positioning and stability. Twenty-seven out of 32 aneurysms (84.38%) were completely occluded with the rate of perioperative complications being 12.50%. Although there was no significant difference between the occlusion rates and complication rates of the two groups, the new shaping method could dramatically decrease the number of coils deployed and reduce the overall procedure time. Patient specific shaping of microcatheters using 3D printing may facilitate easier and safer procedures in coil embolization of intracranial aneurysms with shorter surgery time and less coils deployed.

Patient and aneurysm factors associated with aneurysm recanalization after coiling

BACKGROUND

One limitation of the endovascular treatment of intracranial aneurysms is aneurysm recanalization. The Analysis of Recanalization after Endovascular Treatment of intracranial Aneurysm (ARETA) study is a prospective multicenter cohort study evaluating the factors associated with recanalization after endovascular treatment.

METHODS

The current analysis is focused on patients treated by coiling or balloon-assisted coiling (BAC). Postoperative, mid-term vascular imaging, and evolution of aneurysm occlusion were independently evaluated by two neuroradiologists. A 3-grade scale was used for aneurysm occlusion (complete occlusion, neck remnant, and aneurysm remnant) and for occlusion evolution (improved, stable, and worsened). Recanalization was defined as any worsening of aneurysm occlusion.

RESULTS

Between December 2013 and May 2015, 16 French neurointerventional departments enrolled 1289 patients. A total of 945 aneurysms in 908 patients were treated with coiling or BAC. The overall rate of aneurysm recanalization at mid-term follow-up was 29.5% (95% CI 26.6% to 32.4%): 28.9% and 30.3% in the coiling and BAC groups, respectively. In multivariate analyses factors independently associated with recanalization were current smoking (36.6% in current smokers vs 24.5% in current non-smokers (OR 1.8 (95% CI 1.3 to 2.4); p=0.0001), ruptured status (31.9% in ruptured aneurysms vs 25.1% in unruptured (OR 1.5 (95% CI 1.1 to 2.1); p=0.006), aneurysm size ≥10 mm (48.8% vs 26.5% in aneurysms <10 mm (OR 2.6 (95% CI 1.8 to 3.9); p<0.0001), wide neck (32.1% vs 25.8% in narrow neck (OR 1.5 (95% CI 1.1 to 2.1); p=0.02), and MCA location (34.3% vs 28.3% in other locations (OR 1.5 (95% CI 1.0 to 2.1); p=0.04).

CONCLUSIONS

Several factors are identified by the ARETA study as playing a role in aneurysm recanalization after coiling: current smoking, aneurysm status (ruptured), aneurysm size (≥10 mm), neck size (wide neck), and aneurysm location (middle cerebral artery). This finding has important consequences in clinical practice.

TRIAL REGISTRATION NUMBER

URL: http://www.clinicaltrials.gov; Unique Identifier: NCT01942512.

The Woven Endobridge as a treatment for acutely ruptured aneurysms: A review of the literature

The Woven Endobridge (WEB; Microvention, Aliso Viejo, California, USA) is a relatively new device which has been shown to be safe and effective for the treatment of wide necked bifurcation aneurysms in multiple prospective Good Clinical Practice studies. However, the vast majority of aneurysms included in these studies have been unruptured. The aim of this review is to summarise the current evidence available on the treatment of ruptured aneurysms with the WEB.

CLinical Assessment of WEB device in Ruptured aneurYSms (CLARYS): results of 1-month and 1-year assessment of rebleeding protection and clinical safety in a multicenter study

Background

The primary goal of the CLARYS study is to assess the protection against rebleeding when treating ruptured bifurcation aneurysms with the Woven EndoBridge (WEB) device.

Methods

The CLARYS study is a prospective, multicenter study conducted in 13 European centers. Patients with ruptured bifurcation aneurysms were consecutively included between February 2016 and September 2017. The primary endpoint was defined as the rebleeding rate of the target aneurysm treated with the WEB within 30 days postprocedure. Secondary endpoints included periprocedural and postprocedural adverse events, total procedure and fluoroscopy times, and modified Rankin Scale score at 1 month and 1 year.

Results

Sixty patients with 60 ruptured bifurcation aneurysms to be treated with the WEB were included. A WEB device was successfully implanted in 93.3%. The rebleeding rate at 1 month and 1 year was 0%. The mean fluoroscopy time was 27.0 min. Twenty-three periprocedural complications were observed in 18 patients and resolved without sequelae in 16 patients. Two of these complications were attributed to the procedure and/or the use of the WEB, leading to a procedure/device-related intraoperative complication rate of 3.3%. Overall mortality at 1 month and 1 year was 1.7% and 3.8%, respectively and overall morbidity at 1 month and 1 year was 15% and 9.6%, respectively. WEB-related 1-month and 1-year morbidity and mortality was 0%.

Conclusions

The interim results of CLARYS show that the endovascular treatment of ruptured bifurcation aneurysms with the WEB is safe and effective and, in particular, provides effective protection against rebleeding. It may induce profound change in the endovascular management of ruptured bifurcation aneurysms.

Safety and Efficacy of the Woven EndoBridge Device for Treatment of Ruptured Intracranial Aneurysms: A Systematic Review and Meta-analysis

BACKGROUND

The Woven EndoBridge device has been increasingly used to treat wide-neck aneurysms, particularly ruptured ones.

PURPOSE

Our aim was to investigate the safety and efficacy of the Woven EndoBridge device in the treatment of ruptured intracranial aneurysms.

DATA SOURCES

All studies evaluating the outcomes of Woven EndoBridge device use in the treatment of ruptured intracranial aneurysms from inception through 2020 were searched on Ovid Evidence-Based Medicine Reviews, EMBASE, MEDLINE, Scopus, and the Web of Science Core Collection.

STUDY SELECTION

Eighteen studies encompassing 487 patients with 496 ruptured aneurysms treated with the Woven EndoBridge device were included.

DATA ANALYSIS

We studied rates of rerupture and retreatment, angiographic outcomes at the last follow-up point, complications, and mortality rates. Data were collected on anticoagulation and antiplatelet use. Meta-analysis was performed using the random effects model.

DATA SYNTHESIS

The rate of late rebleeding was 1.1% (95% CI, 0.1%-2.1%). The treatment-related perioperative complication rate and the overall clinical complication rate were 13.2% (95% CI, 9.2%-17.2%) and 3.2% (95% CI, 1.6%-4.7%), respectively. Thirteen hemorrhagic (2%; 95% CI, 0.8%-3.3%) and 41 thromboembolic (6.8%; 95% CI, 4.6%-9%) complications occurred. Favorable clinical outcomes were achieved in 85% of patients. Procedure-related mortality and overall mortality rates were 2.1% (95% CI, 0.8%-3.3%) and 11.5% (95% CI, 7%-16%), respectively. At last follow-up, an adequate occlusion rate was 87.3% (95% CI, 82.1%-92.4%) and the retreatment rate was 5.1% (95% CI, 3%-7.3%).

LIMITATIONS

Our meta-analysis is limited by selection bias and high heterogeneity.

CONCLUSIONS

This meta-analysis demonstrated the safety and efficacy of the Woven EndoBridge device in the management of ruptured aneurysms, but further studies are needed.

Aneurysm treatment with WEB in the cumulative population of two prospective, multicenter series: 3-year follow-up

BACKGROUND

WEB treatment is an endovascular approach for wide-neck bifurcation aneurysms that has demonstrated high safety and good efficacy in mid-term follow-up. While evaluating safety in the long term is important to determine if delayed adverse events occur affecting late morbidity and mortality, the most important point to evaluate is the long-term stability of aneurysm occlusion. The current analysis reports the 3-year clinical and anatomical results of WEB treatment in the combined population of two European trials (WEBCAST (WEB Clinical Assessment of Intrasaccular Aneurysm Therapy) and WEBCAST-2).

METHODS

Aneurysm occlusion was evaluated using a 3-grade scale: complete occlusion, neck remnant, and aneurysm remnant.

RESULTS

The safety population comprised 79 patients. The efficacy population comprised 61 aneurysms. Aneurysm locations were middle cerebral artery in 32/61 aneurysms (52.5%), anterior communicating artery in 13/61 (21.3%), basilar artery in 9/61 (14.8%), and internal carotid artery terminus in 7/61 (11.5%). No adverse events related to the device or procedure occurred between 2 and 3 years. At 3 years, complete occlusion was observed in 31/61 (50.8%) aneurysms, neck remnant in 20/61 (32.8%), and aneurysm remnant in 10/61 (16.4%). Between 1 year and 3 years, aneurysm occlusion was improved or stable in 53/61 (86.9%) aneurysms and worsened in 8/61 (13.1%). Worsening was mostly from complete occlusion to neck remnant in 6/61 (9.8%) aneurysms. The retreatment rate at 3 years was 11.4%.

CONCLUSIONS

This analysis confirms the high safety profile of WEB. Moreover, evidence demonstrates the great stability of aneurysm occlusion with adequate occlusion (complete occlusion or neck remnant) in 83.6% of aneurysms.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. WEBCAST and WEBCAST-2: Unique identifier: NCT01778322.

Comaneci Device for Temporary Coiling Assistance for Treatment of Wide-Necked Aneurysms: Initial Case Series and Systematic Literature Review

BACKGROUND

Coiling of wide-necked aneurysms requires high-density packing of coils within the aneurysm, which necessitates adequate microcatheter access and navigability. The Comaneci device, introduced in the United States in 2019, is a retrievable stent that can be used as an adjunct to coiling of a wide-necked aneurysm without limiting flow. We present a case series and systematic review of use of this device.

METHODS

All cases involving use of the device at our institute between May 1, 2019, and April 30, 2020, were reviewed. A comprehensive systematic review of the literature was conducted using PubMed and EMBASE and a review of eligible article bibliographies.

RESULTS

Five patients underwent Comaneci-assisted wide-necked aneurysm coiling during the study period; 4 were treated via a radial artery approach, and 1 was treated via a femoral artery approach. Two patients presented with subarachnoid hemorrhage: 1 had a ruptured posterior inferior cerebellar artery aneurysm (Hunt-Hess 5, Fisher 4), and 1 had a ruptured middle cerebral artery aneurysm (Hunt-Hess 2, Fisher 1). Mean aneurysmal neck size was 4.4 ± 0.8mm; mean aspect ratio was 1.2 ± 0.3. Raymond-Roy 1 occlusion was achieved in all aneurysms except the posterior inferior cerebellar artery aneurysm. Systematic literature review identified 4 articles that found use of the Comaneci device to treat wide-necked aneurysms to be effective.

CONCLUSIONS

This device can be used with transfemoral and transradial approaches, allowing for continued flow through the parent vessel during the coiling procedure while providing a scaffold for dense coiling of the aneurysm and its neck.

Immediate post-operative aneurysm occlusion after endovascular treatment of intracranial aneurysms with coiling or balloon-assisted coiling in a prospective multicenter cohort of 1189 patients: Analysis of Recanalization after Endovascular Treatment of intracranial Aneurysm (ARETA) Study

BACKGROUND

Coiling, including balloon-assisted coiling (BAC), is the first-line therapy for ruptured and unruptured aneurysms. Its efficacy can be clinically evaluated by bleeding/rebleeding rate after coiling, and anatomically evaluated by aneurysm occlusion post-procedure and during follow-up. We aimed to analyze immediate post-coiling aneurysm occlusion and associated factors within the Analysis of Recanalization after Endovascular Treatment of intracranial Aneurysm (ARETA) population.

METHODS

Between December 2013 and May 2015, 16 neurointerventional departments prospectively enrolled participants treated for ruptured and unruptured aneurysms (ClinicalTrials.gov: NCT01942512). Participant demographics, aneurysm characteristics, and endovascular techniques were recorded. In patients with aneurysms treated by coiling or BAC, immediate post-operative aneurysm occlusion was independently evaluated by a core lab using a 3-grade scale: complete occlusion, neck remnant, and aneurysm remnant.

RESULTS

Of 1135 participants (age 53.8±12.8 years, 754 women (66.4%)), 1189 aneurysms were analyzed. Treatment modality was standard coiling in 645/1189 aneurysms (54.2%) and BAC in 544/1189 (45.8%). Immediate post-operative aneurysm occlusion was complete occlusion in 57.8%, neck remnant in 34.4%, and aneurysm remnant in 7.8%. Adequate occlusion (complete occlusion or neck remnant) was significantly more frequent in aneurysms with size <10 mm (93.1% vs 86.3%; OR 1.8, 95% CI 1.1 to 3.2; p=0.02) and in aneurysms with a narrow neck (95.8% vs 89.6%; OR 2.5, 95% CI 1.5 to 4.1; p=0.0004). Patients aged <70 years had significantly more adequate occlusion (92.7% vs 87.2%; OR 1.9, 95% CI 1.1 to 3.4; p=0.04).

CONCLUSIONS

Immediately after aneurysm coiling, including BAC, adequate aneurysm occlusion was obtained in 92.2%. Age <70 years, aneurysm size <10 mm, and narrow neck were factors associated with adequate occlusion.

TRIAL REGISTRATION NUMBER

NCT01942512, http://www.clinicaltrials.gov.

Surface-modified flow diverter p48-MW-HPC: Preliminary clinical experience in 28 patients treated in two centers

BACKGROUND AND PURPOSE

Flow diversion is increasingly used for endovascular treatment of distal intracranial aneurysms and has led to the development of small diameter flow diverters such as p48-MW (phenox, Bochum, Germany). Use of flow diverters is limited, however, as patients require dual antiplatelet treatment to avoid thromboembolic complications. Hydrophilic Polymer Coating was developed to reduce platelet aggregation on the p48-MW (p48-MW-HPC). This study reports preliminary experience with p48-MW-HPC in aneurysm treatment in two centers.

MATERIALS AND METHODS

Patients with ruptured, unruptured, and recanalized aneurysms treated with p48-MW-HPC were prospectively included and retrospectively analyzed for safety and efficacy. Safety was evaluated by analyzing intra- and postoperative complications as well as thromboembolic events depicted by DWI in the 72 h post-procedure. Efficacy was evaluated at 6 months based on aneurysm occlusion.

RESULTS

From April 2019 to May 2020, 28 patients aged 25-82 years with 29 aneurysms were treated. Two thromboembolic events (7.1%) were reported with good clinical outcome. Final morbidity and mortality were both 0.0%. Post-operative DWI-MRI was depicting lesions in 70.0% of patients. Short-term (6 months) anatomical results were complete aneurysm occlusion in 87.0% of aneurysms, neck remnant in 8.7%, and aneurysm remnant in 4.3%.

CONCLUSION

This preliminary clinical evaluation conducted in a relatively small sample size shows high feasibility (100.0%) of p48-MW-HPC aneurysm treatment, without morbidity or mortality, and high efficacy (complete occlusion in 90.0%). Additional larger comparative studies are needed to confirm these results and optimize perioperative antiplatelet treatment.

Increased rupture risk in small intracranial aneurysms associated with methamphetamine use

BACKGROUND

Aneurysmal subarachnoid hemorrhage (SAH) is the most common cause of nontraumatic SAH. Current guidelines generally recommend observation for unruptured intracranial aneurysms smaller than 7 mm, for those are considered at low risk for spontaneous rupture according to available scoring systems.

OBJECTIVE

We observed a tendency for SAH in small intracranial aneurysms in patients who are methamphetamine users. A retrospective, single center study to characterize the size and location of ruptured and unruptured intracranial aneurysms in methamphetamine users was performed.

MATERIALS AND METHODS

Clinical characteristics and patient data were collected via retrospective chart review of patients with intracranial aneurysms and a history of methamphetamine use with a specific focus on aneurysm size and location.

RESULTS

A total of 62 patients were identified with at least one intracranial aneurysm and a history of methamphetamine use, yielding 73 intracranial aneurysms (n = 73). The mean largest diameter of unruptured aneurysms (n = 44) was 5.1 mm (median 4.5, SD 2.5 mm), smaller than for ruptured aneurysms (n = 29) with a mean diameter of 6.3 mm (median 5.5, SD 2.5 mm). Aneurysms measuring less than 7 mm presented with SAH in 36.5%. With regard to location, 28% (n = 42) of anterior circulation aneurysms less than 7 mm presented with rupture, in contrast to 70% (n = 10) of posterior circulation aneurysms which were found to be ruptured.

CONCLUSIONS

Methamphetamine use may be considered a significant risk factor for aneurysmal SAH at a smaller aneurysm size than for other patients. These patients may benefit from a lower threshold for intervention and/or aggressive imaging and clinical follow-up.

Delayed thromboembolic events after coiling of unruptured intracranial aneurysms in a prospective cohort of 335 patients

BACKGROUND

Coiling is the first-line treatment for the management of unruptured intracranial aneurysms (UIAs), but delayed thromboembolic events (TEEs) can occur after such treatment. ARETA (Analysis of Recanalization after Endovascular Treatment of Intracranial Aneurysm) is a prospective multicenter study conducted to analyze aneurysm recanalization. We analyzed delayed TEEs in the UIA subgroup.

METHODS

Sixteen neurointerventional departments prospectively enrolled patients treated for ruptured and unruptured aneurysms between December 2013 and May 2015. Participant demographics, aneurysm characteristics, and endovascular techniques were recorded. Data were analyzed from participants with UIA treated by coiling or balloon-assisted coiling. We assessed the rates, timing, management, clinical outcomes, and risk factors for delayed TEEs using univariable and multivariable analyses.

RESULTS

The rate of delayed TEEs was 2.4% (95% CI 1.0% to 4.6%) in patients with unruptured aneurysms, with all events occurring in the week following the procedure. In multivariate analysis, two factors were associated with delayed TEEs: autosomal dominant polycystic kidney disease (ADPKD): 20.0% in patients with ADPKD vs 1.9% in patients without ADPKD (OR 27.3 (95% CI 3.9 to 190.2), p=0.0008) and post-procedure aneurysm remnant: 9.4% in patients with post-procedure aneurysm remnant vs 1.6% in patients with adequate occlusion (OR 9.9 (95% CI 1.0 to 51.3), p=0.006). We describe modalities of management as well as clinical outcomes.

CONCLUSIONS

Delayed TEE is a relatively rare complication after coiling of UIAs. In this series, all occurred in the week following the initial procedure. Two factors were associated with delayed TEE: ADPKD and aneurysm remnant at procedure completion.

CLINICAL TRIAL REGISTRATION

NCT01942512.

Safety and efficacy of complete versus near-complete coiling in treatment of intracranial aneurysms

Objective

This study aimed to evaluate the clinical and angiographic outcomes of aneurysms that were completely or near-completely embolized and ascertain whether complete embolization is important in the stent-assisted coiling (SAC) of intracranial aneurysms.

Methods

This retrospective study enrolled 390 patients (417 aneurysms). Among them, complete (100%) or near-complete (>90%) angiographic obliteration of the aneurysms on immediate angiography was accomplished. Baseline characteristics, complications, angiography follow-up results, and clinical outcomes were analyzed.

Results

Cumulative adverse events occurred in 30 patients (7.7%), including thromboembolic complications in 17 (4.4%), intraoperative rupture in 10 (2.6%), and others in 3 (0.8%). Statistical analyses revealed an increased intraprocedural rupture rate in the initial completely occluded aneurysms (5.6% compared with 1.0%). The incidence of cumulative adverse events was higher in patients with completely occluded aneurysms (11.1%) than in those with near-completely occluded aneurysms (5.5%). Angiography follow-up was available for 173 aneurysms. Aneurysm occlusion status at follow-up was correlated with stent placement (p ​= ​0.000, odds ratio ​= ​5.847), size (p ​= ​0.000, odds ratio ​= ​6.446 for tiny aneurysms; and p ​= ​0.001, odds ratio ​= ​5.616 for small aneurysms), and initial aneurysm occlusion status (p ​= ​0.001, odds ratio ​= ​3.436). Complete occlusion at follow-up was seen in 82.6% of the initial complete occlusion group versus 63.0% of the initial near-complete occlusion group. The incidence of complete occlusion at follow-up was higher in the initial completely occluded aneurysms with SAC (100%) than in the initial completely occluded aneurysms with non-SAC (65.2%).

Conclusions

Initial complete treatment may lead to higher complication rates and good clinical outcomes at follow-up. Stent placement may enhance progressive aneurysm occlusion. Initial complete occlusion with SAC can provide durable closure at follow-up.

Rebleeding and bleeding in the year following intracranial aneurysm coiling: analysis of a large prospective multicenter cohort of 1140 patients-Analysis of Recanalization after Endovascular Treatment of Intracranial Aneurysm (ARETA) Study

BACKGROUND

Endovascular treatment is the first line therapy for the management of ruptured and unruptured intracranial aneurysms, but delayed aneurysm rupture leading to bleeding/rebleeding can occur subsequently. ARETA (Analysis of Recanalization after Endovascular Treatment of intracranial Aneurysm) is a prospective, multicenter study conducted to analyze aneurysm recanalization. We analyzed delayed bleeding and rebleeding in this large cohort.

METHODS

16 neurointerventional departments prospectively enrolled patients treated for ruptured and unruptured aneurysms between December 2013 and May 2015 (ClinicalTrials.gov: NCT01942512). Participant demographics, aneurysm characteristics and endovascular techniques were recorded. Data were analyzed from participants with ruptured or unruptured aneurysms treated by coiling or balloon-assisted coiling. Rates of bleeding and rebleeding were analyzed and associated factors were studied using univariable and multivariable analyses.

RESULTS

The bleeding rate was 0.0% in patients with unruptured aneurysms and 1.0% (95% CI 0.3% to 1.7%) in patients with ruptured aneurysms. In multivariate analysis, two factors were associated with rebleeding occurrence: incomplete aneurysm occlusion after initial treatment (2.0% in incomplete aneurysm occlusion vs 0.2% in complete aneurysm occlusion, OR 10.2, 95% CI 1.2 to 83.3; p=0.03) and dome-to-neck ratio (1.5±0.5 with rebleeding vs 2.2±0.9 without rebleeding, OR 0.2, 95% CI 0.04 to 0.8; p=0.03). Modalities of management of aneurysm rebleeding as well as clinical outcomes are described.

CONCLUSIONS

Aneurysm coiling affords good protection against bleeding (for unruptured aneurysms) and rebleeding (for ruptured aneurysms) at 1 year with rates of 0.0% and 1.0%, respectively. Aneurysm occlusion and dome-to-neck ratio are the two factors that appear to play a role in the occurrence of rebleeding.