Aneurysm Occlusion Research Articles

The pEGASUS-HPC stent system for stent-assisted coiling of cerebral aneurysms: a multicenter case series

BackgroundStent-assisted coiling (SAC) is a well-established method for treatment of wide-necked intracranial aneurysms. In this multicenter, retrospective case series we evaluated SAC with a new low-profile, laser-cut stent with an...

Vanguard Study: Initial experience with the new fourth generation Pipeline Vantage Flow Diverter (PVFD): 6-month results, technical and clinical considerations

BackgroundThe Pipeline Embolization Device has proven to be a safe and effective device for the treatment of intracranial aneurysms. The Pipeline Vantage Flow Diverter (PVFD) with Shield Technology is the...

Woven EndoBridge versus stent-assisted coil embolization for the treatment of ruptured wide-necked aneurysms: A multicentric experience.

The potentially higher risk of hemorrhagic complications is of concern in stent-assisted coiling (SAC) of ruptured wide-necked intracranial aneurysms (IAs). The Woven EndoBridge (WEB) is considered an appealing alternative since antiplatelet therapy is not required. Herein, we aimed to compare the safety and effectiveness of WEB vs. SAC for the treatment of ruptured wide-necked IAs. This was an international cross-sectional study of consecutive patients treated for ruptured wide-neck IAs with WEB or SAC at four high-volume neurovascular centers between 2019 and 2022. Primary and secondary efficacy outcomes were radiographic aneurysm occlusion at follow-up and functional status at last follow-up. Safety outcomes included periprocedural hemorrhagic/ischemia-related complications. One hundred five patients treated with WEB and 112 patients treated with SAC were included. The median procedure duration of endovascular treatment was shorter for WEB than for SAC (69 vs. 76 min; p = 0.04). There were no significant differences in complete aneurysm occlusion rates (SAC: 64.5% vs. WEB: 60.9%; adjusted OR [aOR] = 0.70; 95%CI 0.34-1.43; p = 0.328). SAC had a significantly higher risk of complications (23.2% vs. 9.5%, p = 0.009), ischemic events (17% vs. 6.7%, p = 0.024), and EVD hemorrhage (16% vs. 0%, p = 0.008). The probability of procedure-related complications across procedure time was significantly lower with WEB compared with SAC (aOR = 0.40; 95%CI 0.20-1.13; p = 0.03). WEB and SAC demonstrated similar obliteration rates at follow-up when used for embolization of ruptured wide-necked IAs. However, SAC showed higher rates of procedure-related complications primarily driven by ischemic events and higher rates of EVD hemorrhage. The overall treatment duration was shorter for WEB than for SAC.

Endovascular complications: Antiplatelet management for flow diversion

Up to 3−5% of the general population is affected by cerebral aneurysms that are associated with both modifiable as well as non-modifiable risk factors ranging from familial to acquired neurovascular conditions. The initial treatment option was aneurysm clipping and evolved to including primary or adjuvant endovascular treatment. Aneurysm re-rupture, although rare, can have devastating consequences such as intracranial bleeding and carotidcavernous fistula. Emergent surgery in view of delayed aneurysm rupture in patients maintained on dual antiplatelet therapy presents with the need to carefully assess the procedure-related risk factors and evaluate the patients’ platelet function. With the advent of novel technology, flow diverters came into play. These devices utilize the deployment of metallic stents into the parent artery that serves the diversion of blood flow away from the pouching aneurysm. Despite their efficacy, flow diverter insertion and catheter manipulation come with a risk of developing ischemia and stroke, hemorrhage and aneurysm re-rupture, in-stent thrombosis and stenosis, and aneurysmal occlusion amongst other complications. The prospect of thromboembolic events necessitates the use of aggressive antiplatelet regimen with the dual antiplatelet regimen utilizing clopidogrel and aspirin used most frequently. Prasugrel and Ticagrelor have been shown to be superior to Clopidogrel in terms of thromboembolic consequences in cardiovascular literature. Given their potential benefit over the current standard of treatment in this patient population, more extensive randomized-controlled studies are warranted for the evaluation of the efficacy and non-inferiority of Prasugrel and Aspirin or Ticagrelor and Aspirin to Clopidogrel and Aspirin.

Pipeline embolization device dynamics: prediction of incomplete occlusion by elongation from nominal length.

According to benchtop studies, the oversizing of a Pipeline embolization device (PED) relative to the parent artery leads to a significant increase in porosity and potentially compromises aneurysm occlusion as well as transitional zone (TZ) formation around the neck of aneurysms. However, no clinical assessment has been reported. Here this potential was studied by measuring the dynamic changes of PEDs in the clinical time course. The authors retrospectively examined 124 anterior circulation unruptured aneurysms in 114 consecutive patients treated with a PED between July 2015 and December 2020 at their institution. The authors excluded 77 cases of 68 patients with adjunctive coil embolization or multiple stents that could affect the PED dynamics and measurements, and 47 aneurysms in 46 patients were included. Measurements were performed before, immediately after, and 6 months after treatment, and then at intervals of 6 months to 1 year after that for nonocclusion cases. Complete occlusion was achieved in 79.0% and incomplete occlusion in 21.0% at last follow-up. The PED length immediately after deployment was 136% nominal length. A multivariable regression analysis revealed that age (OR 1.11/year; p = 0.02) and PED elongation from nominal length (OR 1.31/mm; p = 0.012) were independently associated with a higher rate of incomplete occlusion at the last follow-up. TZ formation did not affect the occlusion rate. PED elongation from the nominal length is a new predictor of incomplete aneurysm occlusion. The PED showed vascular remodeling by changing its diameter and length in the clinical course. TZ formation was remodeled and did not affect the occlusion rate.

Predictors of occlusion, long-term outcomes, and safety in a cohort of 674 aneurysms treated with the Pipeline embolization device.

By providing a more physiological approach to the treatment of intracranial aneurysms, the Pipeline embolization device (PED) has revolutionized the endovascular treatment of aneurysms. Although there are many flow diverters on the market, the authors report their experience with the PED, the first flow diverter to be approved by the Food and Drug Administration. They aimed to assess the efficacy and safety of PED flow diversion for the treatment of a wide range of aneurysms, as well as to look at factors affecting occlusion. This is a retrospective study of a prospectively maintained database of patients treated with the PED between January 2011 and December 2019. Charts were reviewed for patient, aneurysm, and procedure characteristics. The primary outcomes of interest were complication rates, occlusion outcomes (O'Kelly-Marotta grading scale), and functional outcomes (modified Rankin Scale [mRS]). Secondary outcomes included predictors of incomplete occlusion at 6 and 24 months of follow-up. The study cohort included 581 patients with 674 aneurysms. Most aneurysms (90.5%) were in the anterior circulation and had a saccular morphology (85.6%). Additionally, 638 aneurysms (94.7%) were unruptured, whereas 36 (5.3%) were acutely ruptured. The largest mean aneurysm diameter was 8.3 ± 6.1 mm. Complications occurred at a rate of 5.5% (n = 32). The complete occlusion rate was 89.3% at 24 months' follow-up, and 94.8% of patients had a favorable neurological outcome (mRS score 0-2) at the last follow-up. On multivariate analysis, predictors of incomplete aneurysm occlusion at 6 months were hypertension (OR 1.7, p = 0.03), previous aneurysm treatment (OR 2.4, p = 0.001), and increasing aneurysm neck diameter (OR 1.2, p = 0.02), whereas a saccular morphology was protective (OR 0.5, p = 0.05). Predictors of incomplete occlusion at 24 months were increasing aneurysm neck diameter (OR 1.2, p = 0.01) and previous aneurysm treatment (OR 2.3, p = 0.01). The study findings are corroborated by those of previous studies and trials. The complete occlusion rate was 89.3% at 24 months' follow-up, with 94.8% of patients having favorable functional outcomes (mRS score 0-2). Aneurysm treatment before PED deployment and an increasing aneurysm neck diameter increase the risk of incomplete occlusion at 6 and 24 months.

Treatment Outcome of Flow Diverter Device for Medium-Sized Cerebral Aneurysms: A Single-Center Report.

Flow diverters (FDs), first introduced in Japan in 2015, were initially limited to wide-necked large cerebral aneurysms, which pose a high treatment risk. However, based on the results of the PREMIER study, the indications have expanded since 2020, and the number of treatment cases is increasing in Japan. At our hospital, FD placement with adjunctive coil embolization has been actively performed for medium-sized cerebral aneurysms, as indicated in the PREMIER study; herein, we report the outcomes of this treatment. Of the 25 patients with 28 aneurysms who underwent FD placement at our institution between April 2022 and June 2023, 15 with 17 wide-necked unruptured cerebral aneurysms with a maximum diameter of <12 mm in the internal carotid artery (ICA) or vertebral artery (VA) were included. Postoperative complications were investigated in each case, and the aneurysm occlusion status was assessed using ultrashort echo time (UTE)-MRA at 3 months postoperatively and angiography at 6 months postoperatively. Fifteen patients who underwent coiling or stent-assisted coiling (SAC) for the same criteria during the same period were compared. Baseline characteristics and treatment results were compared between FD and coiling/SAC cases. Four males and 11 females with a mean age of 61.7 ± 12.8 years were included, and the median follow-up period was 9 months (6-18 months). There were 14 aneurysms of the ICA and 3 of the VA, and the mean maximum aneurysm diameter was 7.9 ± 1.7 mm. All patients were treated using the Pipeline Flex with Shield Technology (Medtronic, Minneapolis, MN, USA), and 14 aneurysms (82.4%) were treated with adjunctive coil embolization. There were no symptomatic strokes in the perioperative period; only one patient receiving corticosteroid therapy for thyroid eye disease had asymptomatic ICA occlusion at 3 months. Fifteen aneurysms (88.2%) were not visible on UTE-MRA at 3 months postoperatively, and angiography at 6 months showed complete occlusion in 16 (94.1%) aneurysms. The coiling/SAC group had a smaller neck size and higher volume embolization ratio than the FD group; however, complete occlusion was higher in the FD group. FD placement with adjunctive coil embolization for medium-sized cerebral aneurysms is expected to result in good occlusion rates in the early postoperative period.

Endoscopic Eyebrow Approach for Aneurysms.

Considerable effort has been made to reduce surgical invasiveness, since Axel Perneczky introduced the supraorbital eyebrow approach as a core part of his keyhole concept in neurosurgery. But a limited approach does not facilitate an already serious and demanding task as aneurysm surgery. In this regard, the enhancement of the visual field before, during, and after microsurgical aneurysm occlusion is a safe and effective method to increase the quality of treatment. Indications/Contraindications: Based on the individual anatomical findings, the supraorbital keyhole approach provides access to most aneurysms of the anterior circulation. The approach is not recommended in large complex aneurysms, giant aneurysms, BA aneurysms located beneath the dorsum sellae, as well as cases of severe subarachnoid hemorrhage (SAH) and expected brain edema. Experience with endoscopic procedures in aneurysm surgery is limited to several clinical retrospective articles, and no major complications in conjunction with the endoscope were observed. Outcome and Prognosis: The supraorbital eyebrow approach has a low rate of complications and provides highly favorable cosmetic results. Endoscopic inspection prior to clipping might reduce overexposure and mobilization of the aneurysm. It was found that the rate of intraoperative rupture was decreased. The endoscopic post-clipping control helped significantly to reduce aneurysm remnants and unattended parent, branch, or perforator occlusion. The supraorbital eyebrow approach is a safe, effective and elegant approach in the treatment of most aneurysms of the anterior circulation. The additional enhancement of the visual field provided by the endoscope before, during, and after microsurgical aneurysm clipping might decrease the rate of intraoperative aneurysm ruptures and unexpected findings concerning aneurysm remnant occlusion and compromise of involved parent, branching, and perforating vessels.

Correlation of Flow Diverter Malapposition at the Aneurysm Neck with Incomplete Aneurysm Occlusion in Patients with Small Intracranial Aneurysms: A Single-Center Experience.

Flow diversion treatment repairs aneurysms by altering the hemodynamics of the aneurysmal sac and providing a scaffold for endothelial cell adhesion. The purpose of this study was to investigate the correlation of flow diverter (FD) malapposition at the aneurysm neck with incomplete occlusion of small intracranial aneurysms (IAs) and investigate other factors that are possibly related to incomplete occlusion. From January 2019 to June 2022, the clinical and imaging data for 153 patients (175 aneurysms) with unruptured small IAs treated with flow diversion were retrospectively analyzed. FD apposition at the aneurysm neck was evaluated by high-resolution conebeam CT (HR-CBCT), and the complete occlusion rate for aneurysms was judged according to the latest follow-up conventional angiography findings (≥6 months). Multivariate logistic regression analysis was used to determine factors associated with incomplete aneurysm occlusion. In total, 159 FDs were implanted in 153 patients. HR-CBCT performed after the deployment revealed FD malapposition at the aneurysm neck in 18 cases. According to the latest follow-up angiograms (average: 9.47 ± 3.35 months), the complete aneurysm occlusion rate was 66.9%. The complete occlusion rates for incomplete and complete stent apposition at the neck were 38.9% (7/18) and 70.1% (110/157), respectively. The results of regression analysis showed that an aneurysm sac with branch vessels (OR, 2.937; P = .018), incomplete stent apposition at the aneurysm neck (OR, 3.561; P = .023), and a large aneurysm diameter (OR, 1.533; P = .028) were positive predictors of incomplete aneurysm occlusion. An aneurysm sac with branch vessels, a large aneurysm diameter, and malapposition at the aneurysm neck significantly affect aneurysm repair after FD stent-only treatment for small IAs.

Predictors of aneurysm shrinkage after flow diversion treatment for internal carotid artery aneurysms: quantitative volume analysis with MRI.

Although aneurysm shrinkage often occurs after flow diversion treatment for intracranial aneurysms, no reports have addressed the factors associated with aneurysm shrinkage. This retrospective single-center study was performed to examine patients with unruptured internal carotid artery aneurysms who were treated using flow diversion and followed up by imaging for at least 12 months. The study outcome was aneurysm shrinkage (volume reduction of ≥10%) 12 months after treatment. Aneurysm volume was quantitatively assessed using the MRIcroGL software. Patient and aneurysm characteristics were statistically analyzed. This study involved 81 patients with 88 aneurysms. At the 6 months, 12 months, and last follow-ups, the proportion of aneurysms that had shrunk was 50, 64, and 65%, respectively. No adjunctive coiling (odds ratio, 56.7; 95% confidence interval, 7.03-457.21; p < 0.001) and aneurysm occlusion (odds ratio, 90.7; 95% confidence interval, 8.32-988.66; p < 0.001) were significantly associated with aneurysm shrinkage. In patients treated by flow diversion with adjunctive coiling, only the volume embolization rate was a factor significantly associated with aneurysm shrinkage (p < 0.001). Its cutoff value was 15.5% according to the receiver operating characteristic curve analysis (area under the curve, 0.87; sensitivity, 0.87; specificity, 0.83). The rate of aneurysm shrinkage after flow diversion increased during the first 12 months after treatment, but not thereafter. No adjunctive coiling and aneurysm occlusion were predictors of aneurysm shrinkage, respectively. If adjunctive coiling is required, a volume embolization rate of ≤15.5% may be suggested for aneurysm regression.

Multicenter study of the safety and effectiveness of intracranial aneurysm treatment with the p64MW-HPC flow modulation device

Background and purpose The new p64 flow diverter with hydrophilic polymer coating (HPC) was designed to reduce thrombogenicity. To date, it is unclear how antithrombogenic surface modifications affect neoendothelialization and thrombus formation in patients with unruptured intracranial aneurysms. The purpose of this study was to evaluate the safety and effectiveness of the p64MW-HPC in the treatment of unruptured aneurysms of small to giant size and of both the anterior and posterior circulation. Materials and methods Between March 2020 and October 2022 all patients with unruptured intracranial aneurysms treated with the p64MW-HPC were included at five neurovascular centers. Demographic data, aneurysm characteristics, antiplatelet therapy, procedural complications, and clinical and angiographic outcomes were recorded. Results A total of 100 patients with 100 unruptured intracranial aneurysms met the inclusion criteria. Eighty-three aneurysms were classified as saccular, 12 aneurysms were fusiform, 4 aneurysms dissecting, and 1 aneurysm was blister-like. Dual antiplatelet therapy with Clopidogrel and Aspirin was given in 68 cases, and with Ticagrelor and Aspirin in 24 cases. Technical issues with deployment were encountered in 14 cases (torsion ( n = 3), foreshortening ( n = 8), and incomplete opening ( n = 3)). Ischemic stroke occurred in a total of seven cases. In one patient a wire perforation and subsequent severe ICH occurred. Complete aneurysm occlusion at angiographic follow-up (mean time = 7 months) was seen in 73% and adequate occlusion in 93%. Conclusion This study is the largest multicenter study to date documenting the safety and effectiveness of the new antithrombogenic p64MW-HPC in the treatment of unruptured intracranial aneurysms of the anterior and posterior circulation.

Our experience with the using of pCONUS2 implant for endovascular occlusion of cerebral bifurcation aneurysms

Objective ‒ to analyze the outcomes of endovascular treatment of aneurysms occluded by microcoils using pCONUS2 implants.Materials and methods. A retrospective analysis of treatment outcomes from January 2021 to March 2023 was conducted at the SO «Scientific-practical center of endovascular neuroradiology NAMS of Ukraine». Among 532 patients with cerebral aneurysms, 22 were treated with bifurcation implants pCONUS2 (Hydrophilic Polymer Coating (HPC)). The study group comprised 22 patients (11 females, 11 males, average age 53.01 years) with 26 aneurysms (3 patients had multiple aneurysms, one of which was excluded from use pCONUS2), including 9 (40.9 %) ruptured aneurysms. All of them were operated on during the acute period. Induction and controlled implantation of pCONUS2 were successfully performed in all patients. No technical problems have been registered that could make it difficult to navigate, start and detach the device. Results. Initial occlusion assessment using the modified Raymond-Roy classification (mRRC) showed total occlusion (mRRC 1) in 12 cases (54.5 %), near-complete occlusion (mRRC 2) in 6 cases (27.3 %), and residual filling (mRRC 3a and 3b) in 4 cases (18.2 %). Twenty-one patients were discharged or transferred for further treatment to the department of neurology with satisfactory treatment results (0–2 points on the modified Rankin Scale). One patient with a basilar artery aneurysm died from subarachnoid hemorrhage and severe vasospasm (6 points on the modified Rankin Scale). Angiographic follow-up was available for 9 patients, with stable occlusion in 7 cases and improvement from mRRC 3a to mRRC 1 in 2 cases.Conclusions. pCONUS bifurcation implants serve as an additional tool for treating wide-neck cerebral aneurysms, demonstrating high technical success rates and low complication and mortality rates.

Contour device implantation for treatment of intracranial aneurysms in the basilar tip

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/cm2. 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.

Dynamic Mixed-Reality Patient-Specific Aneurysm Clipping Simulation for Two Cases-A Feasibility Study.

Intracranial aneurysm (IA) clipping is a complex neurosurgical procedure which demands advanced technology to minimize risks and maximize patient outcomes. This study aims to evaluate the feasibility of training patient-specific microsurgical clipping procedures using a mixed-reality physical neurosurgical simulator for unruptured IA. Two board-certified neurosurgeons were asked to simulate surgery in 2 patient-specific left-side unruptured middle cerebral artery-bifurcation IA models. The study was conducted in the operation theater under realistic conditions using a mixed-reality physical neurosurgical simulator. Time, procedural, and outcome-related information was collected. The participating neurosurgeons were encouraged to attempt all possible clipping strategies, even those deemed suboptimal, reporting the outcome of each strategy. Finally, to evaluate the feasibility and added value of integrating indocyanine green fluorescence angiography (ICG-FA) with the simulator, the ICG-FA videos for each clipping strategy were analyzed and compared with the reported clipping outcomes. Between 4 and 8, different clipping strategies were applied per aneurysm model; the number of strategies was higher in Patient Model 1 (6.5 ± 1.5) (more complex aneurysm) than in Patient Model 2 (5.0 ± 1.0). The clipping strategies differed between surgeons. At most, 53.5 minutes were necessary to complete each training session, but more than double the time was spent on the more complex aneurysm. Up to 53.8% (Patient Model 1) and 50% (Patient Model 2) of the attempted strategies were discarded by the neurosurgeons during the simulation. Evaluation of aneurysm occlusion through ICG-FA was specific, although sensitivity was poor. The present mixed-reality patient-specific simulator allows testing, anticipating, and discarding different aneurysm microsurgical clipping strategies regardless of the pathology complexity. Specific limitations should be considered regarding ICG-FA aneurysm inspection after clipping.

Ongoing Geometric Remodeling of the Parent Artery After Flow-Diverter Stent Reconstruction in Cerebral Aneurysms: The Device Design Matters

Configuration changes of the parent artery (PA) after flow-diverter (FD) stent reconstruction, caused by the bending force of the device, may have an additional role in aneurysm occlusion as a result of the secondary alteration of intra-aneurysmal hemodynamics related to the geometry alteration of the vessel. To determine the degree of PA deformation and aneurysm occlusion rates after deployment of 2 different types of FD. Patients treated with 2 different designs of cobalt-chromium braid (48 and 64 wire braid) structure FD were subject to analysis. Vascular angle changes at the level of the reconstructed segment immediately after FD deployment and at 1 year follow-up were measured and the potential relationship with aneurysmal occlusion rate was analyzed. Forty-two patients harboring 48 aneurysms were included in the present study. The aneurysms were divided into side wall (85.4%) and bifurcation types (14.6%). Twenty-six aneurysms were treated using the Pipeline FD (48 wire braid; 54.2%) and 22 using the Evolve FD (64 wire braid; 45.8%). Of the 48 aneurysms, 42 (87.5%) met the primary end point of complete occlusion at 12 months. The median postdeployment angle change was 7.04°± 4.59° for the Pipeline and 5.05°± 2.49° for the Evolve, whereas the median 12 months follow-up angle change was 15.49°± 10.99° and 10.01°± 8.83°, respectively. PA angle changes were significantly higher in the bifurcation group compared with the side wall group both during procedure and at 12 months follow-up. Angle change had a statistically nonsignificant association with complete aneurysm occlusion. PA deformation starts immediately after deployment and remodeling continues for 1 year after. Aneurysms located in the vessel bifurcation were more prone to PA straightening after FD deployment than were side wall aneurysms. Furthermore, Pipeline seemed to be more prone to inducing vascular deformation, compared with Evolve.

Safety and efficacy of endovascular versus microsurgical treatment of unruptured wide-necked middle cerebral artery aneurysms: a propensity score-matched analysis of the NeuroVascular Quality Initiative Quality Outcomes Database Cerebral Aneurysm Registry.

Unruptured, wide-necked middle cerebral artery (WN-MCA) aneurysms have traditionally been considered ideal candidates for microsurgery (MS), although endovascular treatment (EVT) has dramatically increased in popularity with the advent of novel devices such as intrasaccular flow disruptors. The purpose of this study was to evaluate the safety and efficacy of MS versus EVT for unruptured WN-MCA aneurysms. The NeuroVascular Quality Initiative Quality Outcomes Database (NVQI-QOD) Cerebral Aneurysm Registry, a multiinstitutional, prospectively collected procedural database, was queried for cases of unruptured WN-MCA aneurysms treated with MS or EVT between 2015 and 2022. A wide neck was defined as an aneurysm neck ≥ 4 mm or a dome/neck ratio ≤ 2. Demographics and aneurysm characteristics were queried. Propensity score matching (PSM) was utilized to match aneurysm size, number of aneurysms treated, patient age, and aneurysm status. Safety outcomes were evaluated including intraoperative and postoperative complication rates. Aneurysm occlusion status and clinical outcomes using the modified Rankin Scale (mRS) score at discharge and the last follow-up were also assessed. Of 671 unruptured MCA aneurysms, 319 were wide necked. Thirty cases were excluded, as the aneurysm had been previously treated. Two hundred eighty-nine operations (203 EVT, 86 MS) in 282 patients satisfied inclusion criteria. After PSM, there were 86 operations in each group for analysis. The mean aneurysm width was 5.0 (EVT) versus 4.9 mm (MS; p = 0.285). Safety data showed similar intraoperative (7.0% EVT vs 3.5% MS, p = 0.496) and postoperative (4.7% vs 7%, p = 0.746) complication rates. The MS patients were more likely to have complete aneurysm occlusion at discharge (90.4% vs 58.8%, p < 0.001). In a limited subset of patients (52.9%) for whom outcome data were available, the EVT patients were more likely to have an mRS score 0 at discharge (50/59 [84.7%] vs 29/54 [53.7%], p < 0.0003] and at the last follow-up (36/55 [65.5%] vs 13/36 [36.1%], p = 0.006). This study describes a large, modern cohort of propensity score-matched patients who underwent treatment of unruptured WN-MCA aneurysms. Safety data on intraoperative and postoperative complication rates were similar in both treatment groups. MS was more likely to result in complete aneurysm occlusion at discharge. In a subset of patients with available outcome data, EVT was associated with better functional outcomes at discharge and the last follow-up. Given the lack of complete follow-up data and rates of retreatment, these results should be interpreted cautiously.

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

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

Predicting incomplete occlusion of intracranial aneurysms treated with flow diverters using machine learning models.

Intracranial saccular aneurysms are vascular malformations responsible for 80% of nontraumatic brain hemorrhage. Recently, flow diverters have been used as a less invasive therapeutic alternative for surgery. However, they fail to achieve complete occlusion after 6 months in 25% of cases. In this study, the authors built a tool, using machine learning (ML), to predict the aneurysm occlusion outcome 6 months after treatment with flow diverters. A total of 667 aneurysms in 616 patients treated with the Pipeline embolization device at a tertiary referral center between January 2011 and December 2017 were included. To build the predictive tool, two experiments were conducted. In the first experiment, six ML algorithms (support vector machine [SVM], decision tree, random forest [RF], k-nearest neighbor, XGBoost, and CatBoost) were trained using 26 features related to patient risk factors and aneurysm morphological characteristics, and the results were compared with logistic regression (LR) modeling. In the second experiment, the models were trained using the top 10 features extracted by Shapley additive explanation (SHAP) analysis performed on the RF model. The results showed that the authors' tool can better predict the occlusion outcome than LR (accuracy of 89% for the SVM model vs 62% for the LR model), even when trained using a subset of the features (83% accuracy). SHAP analysis revealed that age, hypertension, smoking status, branch vessel involvement, aneurysm neck, and larger diameter dimensions were among the most important features contributing to accurate predictions. In this study, an ML-based tool was developed that successfully predicts outcome in intracranial aneurysms treated with flow diversion, thus helping neurosurgeons to practice a more refined approach and patient-tailored medicine.

The Safety and Efficacy of Leo Stents with Coiling or Alone for Anterior Cerebral Artery Aneurysms.

Treatment of anterior cerebral artery (ACA) aneurysms is still not well established. The Leo stent with blood flow direction is a retrievable stent for intracranial aneurysms, whereas it needs to be studied clearly in patients with ACA aneurysms. Consecutive patients with ACA aneurysms were retrospectively enrolled in three neurosurgical centers between January 2016 and October 2021. The data on demographics, aneurysm characteristics, symptom resolution, and postoperative course were collected and analyzed. The aneurysm occlusion status was appraised by Raymond-Ray Occlusion Class (RROC). A total of 57 patients with ACA aneurysms were included in our study. Immediate postprocedural angiograms showed that 20 aneurysms (35.1%) were in complete occlusion (RROC 1), 26 aneurysms (45.6%) were in near-complete occlusion (RROC 2), 11 aneurysms (19.3%) were in incomplete occlusion (RROC 3). The angiographic follow-up found that the rate of complete occlusion increased to 57.9%, and near-completion and incomplete occlusion dropped to 29.8% and 12.3%, respectively. The angiographic result of the last follow-up improved significantly (Z=- 2.805, P=0.005). Univariate analysis indicated that distal location of aneurysms (Z=4.538, P=0.033) and ruptured aneurysms (χ2=.6120, P=0.032) were potential risk factors for intra-parent artery narrowing. Furthermore, multivariate logistic regression analysis found that A3 aneurysms (95% CI 1.427~32.744, P=0.016) are the key risk factor for intra-parent artery narrowing. The Leo stent is safe and effective for aneurysms located in ACA circulations. The overall occlusion degree improved during follow-up. A distal, small artery was the risk factor for intra-parent artery narrowing.

Endovascular treatment of mycotic aneurysms: An update meta-analysis

IntroductionIntracranial mycotic or infectious aneurysms result from the infection of arterial walls, most caused by bacterial or fungal organisms. These infections can weaken the arterial wall, leading to the formation of an aneurysm, a localized dilation, or a bulge. The management can be conservative mainly based on antibiotics or invasive methods such as clipping or endovascular treatment. PurposeWe performed a systematic review and meta-analysis of the current literature on endovascular treatment of mycotic aneurysms, analyzing the safety and efficacy associated with this procedure. MethodsWe systematically searched on PUBMED, Cochrane Library, Embase, and Web of Science databases. Our search strategy was carefully crafted to conduct a thorough investigation of the topic, utilizing a comprehensive combination of relevant keywords. This meta-analysis included all studies that reported endovascular treatment of mycotic aneurysms. To minimize the risk of bias, studies with fewer than four patients, studies where the main outcome was not found, and studies with no clear differentiation between microsurgical and endovascular treatment were excluded. ResultsIn a comprehensive analysis of 134 patients, it was observed that all except one patient received antibiotics as part of their treatment. Among the patients, 56% (a total of 51 out of 90 patients) underwent cardiac surgery. Additionally, three patients required a craniotomy following endovascular treatment. 12 patients experienced morbidity related to the procedures performed, indicating complications arising from the interventions. Furthermore, four aneurysms experienced rebleeding while treatment. A pooled analysis of the endovascular treatment of the mycotic aneurysm revealed a good level of technical success, achieving a 100% success rate in 12 out of 14 studies (97–100%; CI 95%; I2 = 0%), as illustrated in Fig. 2. Similarly, the aneurysm occlusion rate demonstrated a notable efficacy, with a success rate of 97% observed in 12 out of 14 studies (97–100%; CI 95%; I2 = 0%), as depicted in Fig. 3. ConclusionThe results strongly support the efficacy of endovascular treatment in achieving technical success, complete aneurysm occlusion, and favorable neurological outcomes. Additionally, the notably low incidence of complications and procedure-related mortality reaffirms the safety and benefits associated with this intervention.