Intracranial Stenting Research Articles

A comparative invitro study of distinct and novel stent geometries on mechanical performances of poly-L-lactic acid cardiovascular stents.

Poly-L-lactic acid (PLLA) is one of the representative polymeric materials serving as bioresorbable stents (BRS) for cardiovascular disease due to its proper biodegradation, high biocompatibility, and adequate mechanical properties among polymer candidates for BRS. However, PLLA BRS as cardiovascular stents also have limitations because their mechanical properties including low radial strength and high elastic recoil are inferior to those of metallic-based BRS stents. In the study, we developed and manufactured distinct and novel types of stent geometries for investigating mechanical properties of thin-walled PLLA BRS (110 μm) for cardiovascular applications. Five key mechanical tests, including radial strength, crimping profile, flexibility, elastic recoil, and foreshortening were performed through a comprehensive analysis. In addition, we applied the finite element method for further validation and insight of mechanical behaviors of the PLLA BRS. Results revealed that Model 2 had advantages in high flexibility as well as radial strengths, which would be a proper option for complex and acutely curved lesions. Model 3 would be an optimum selection for stent placement in mild target site due to its strength in minimum elastic recoil. Even though Model 4 showed the highest radial strength, finite element simulation showed that the geometry caused higher maximum stress than that of Model 2 and Model 3 during the crimping process. Model 1 showed the most vulnerable geometry among the tested models in both invitro and finite element analysis. Such data may suggest potential guidance in regard to understanding the mechanical behaviors of PLLA BRS as not only applicable cardiovascular but also peripheral and intracranial stents.

Ultra-high resolution CT angiography for the assessment of intracranial stents and flow diverters using photon counting detector CT

BackgroundThe patency of intracranial stents may not be reliably assessed with either CT angiography or MR angiography due to imaging artifacts. We investigated the potential of ultra-high resolution CT angiography...

Use of Onyx Frontier™ for intracranial stenting in stroke patients: A multicenter retrospective study.

Acute ischemic stroke (AIS) due to intracranial atherosclerotic disease (ICAD) carries a high risk of recurrence despite aggressive medical management. The aim of our study is to present our initial experience with the Onyx Frontier™ balloon-mounted drug-eluting stent (Medtronic, Santa Rosa, CA) for AIS due to ICAD. We conducted a multicenter retrospective cohort study describing the technical feasibility, safety, and performance of using the Onyx Frontier™ balloon-mounted drug-eluting stent in patients with acute intracranial vessel occlusion due to ICAD across three comprehensive stroke centers in the United States. We included 23 patients in our study (mean age 67.3 [10.7]; females: n = 13/23, 56.5%). Most patients were Black (n = 14/23, 60.9%). The most common site of vessel occlusion was the M1 branch of the middle cerebral artery (MCA) (n = 14/23, 60.9%), followed by the vertebrobasilar system (n = 5/23, 21.7%), and the internal carotid artery (n = 3/23, 13.0%). Treatment with the Onyx Frontier™ stent was associated with a final mTICI score ≥2b for 100% of patients, with no vessel perforations or distal embolization. None of the patients had any restenosis or re-treatment over a median follow-up of 3.5 months (interquartile range [IQR] 7.8). All cases required a single stent except for one, where two were deployed. Transfemoral access was used in most cases (n = 18/23, 78.3%), with one in-hospital death due to access site complication (n = 1/23, 4.3%). This is the largest multicenter cohort study demonstrating the feasibility and safety of using the Onyx Frontier™ balloon-mounted zotarolimus-eluting stent to treat symptomatic AIS due to ICAD.

Predictors and Outcomes of Periprocedural Intracranial Hemorrhage after Stenting for Symptomatic Intracranial Atherosclerotic Stenosis.

Periprocedural intracranial hemorrhage is one of common complications after stent placement for symptomatic intracranial atherosclerotic stenosis. This study was conducted to demonstrate predictors and long-term outcomes of periprocedural intracranial hemorrhage after stent placement for symptomatic intracranial atherosclerotic stenosis. We retrospectively analyzed patients with symptomatic intracranial atherosclerotic stenosis stent placement in a prospective cohort at a high-volume stroke center. Clinical, radiologic, and periprocedural characteristics and long-term outcomes were reviewed. Periprocedural intracranial hemorrhage was classified as procedure-related hemorrhage (PRH) and non-procedure-related hemorrhage (NPRH). The long-term outcomes were compared between patients with PRH and NPRH, and the predictors of NPRH were explored. Among 1849 patients, 24 (1.3%) had periprocedural intracranial hemorrhage, including PRH (4) and NPRH (20). The postprocedural 30-day mRS was 0-2 in 9 (37.5%) cases, 3-5 in 5 (20.8%) cases, and 6 in 10 (41.7%) cases. For the 14 survivors, the long-term (median of 78 months) mRS were 0-2 in 10 (76.9%) cases and 3-5 in 3 (23.1%) cases. The proportion of poor long-term outcomes (mRS ≥3) in patients with NPRH was significantly higher than those with PRH (68.4% versus 0%, P = .024). Anterior circulation (P = .002), high preprocedural stenosis rate (P < .001), and cerebral infarction within 30 days (P = .006) were independent predictors of NPRH after stent placement. Patients with NPRH had worse outcomes than those with PRH after stent placement for symptomatic ICAS. Anterior circulation, severe preprocedural stenosis, and recent infarction are independent predictors of NPRH.

Adjunctive venous sinus stenting in transvenous embolization of vein of Galen malformations.

Vein of Galen malformations are congenital arteriovenous malformations primarily treated by endovascular embolization via transarterial or transvenous approaches. transvenous embolization can be utilized to close the malformation but may be difficult in patients with venous stenosis or blockages, which drive venous hypertension and lead to significant neurologic consequences. Here, we illustrate the atypical placement of an intracranial venous sinus stent to improve outflow after transvenous embolization in pediatric patients with the vein of Galen malformation. A retrospective review of clinical databases at two high-volume endovascular centers from January 2018 to March 2023 identified all vein of Galen malformation patients who received a venous sinus stent during transvenous embolization. Clinical data, imaging, angioarchitecture, operative details, postoperative management, and follow-up were reviewed. Three patients presented for transvenous embolization after multiple staged transarterial embolizations of their vein of Galen malformation. Transvenous access was complicated by lateral sinus stenosis, which was temporarily relieved by balloon angioplasty. After transvenous embolization by pressure cooker technique, the dural sinuses were stented using the existing venous guide catheter. Venous angiography demonstrated improved flow across the stenosed areas and post-embolization angiography demonstrated normalized venous drainage with widely patent stents. One patient experienced postoperative oculomotor nerve palsy unrelated to the stent placement. All patients demonstrated a complete cure of their vein of Galen malformations with patent venous sinus stents on follow-up. In patients with the vein of Galen malformation and venous hypertension receiving transvenous embolization, venous sinus stenting may be a safe and effective option to reduce aberrant cortical venous drainage and improve normal outflow. Further studies are warranted to investigate its benefit in high-flow vascular malformations.

Intra Arterial Tirofiban in the Peri Operative Priming for Intracranial Stent Deployment in Aneurysms – A cross Sectional Study

Introduction: Tirofiban is a glycoprotein IIb/IIIa receptor antagonist that inhibits platelet aggregation. Primary and secondary objectives of this study were to determine the efficacy and to determine the safety profile of intra arterial tirofiban in the peri operative priming for intracranial stent deployment in aneurysms respectively. Materials and methods: This was a cross sectional study in a tertiary care centre in Kerala. Patient admitted with sub arachnoid haemorrhage/aneurysm posted for endovascular stent associated procedures and willing for the study were selected. The pre procedure assessment of neurological status was done. Patient underwent the procedure where peri operative priming with intraarterial tirofiban was given. The development of any neurological deficits within 24 hours was assessed using Glasgow coma scale and National Institute Health Stroke Scale. Laboratory blood parameters before and after procedure were also reviewed. Results: Study involved 58 patients with aneurysm who were given intraarterial tirofiban. No significant difference (p value 0.521) in Glasgow coma scale on admission (14.89 ± 0.462) and on discharge (14.74 ±1.650). Analysis was done using SPSS version 20.00. Paired samples T test and Wilcoxon Signed Rank Test were used. Conclusion: Results showed that intra arterial tirofiban is effective and the procedure was uneventful with no complications. Patients recovered well and the hospital stay was of minimum duration.

ANew Fibrin-Heparine Coated Self-Expanding Stent for the Rescue Treatment of Intracranial Stenosis-aMulticentric Study.

Rescue intracranial stenting is necessary to provide sufficient recanalization after mechanical thrombectomy (MT) in patients with acute large vessel occlusions (LVO) due to an underlying intracranial atherosclerotic disease (ICAD). The CREDO heal is anovel stent that provides apotentially lower thrombogenicity due to surface modification. We present the first multicentric experience with the CREDO heal for acute rescue stenting. Data of 81patients who underwent rescue stenting after MT at 12centers in Germany and Spain were prospectively collected and retrospectively evaluated. Final mTICI2b‑3 was reached in 95.1% after median two MT maneuvers and stenting. Four periprocedural complications resulted in clinical deterioration (4.9%). Intraparenchymal hemorrhage occurred in one patient (1.2%) and functional independence at FU was reached by 42% of the patients. Most interventions were performed under Gp IIb/IIIa inhibitors. CREDO heal was effective and safe in our case series. However, more data is needed to define the optimal antithrombotic regime. The use under single antiplatelet medication is not supported by our study.

Stable and Thin-Polymer-Based Modification of Neurovascular Stents with 2-Methacryloyloxyethyl Phosphorylcholine Polymer for Antithrombogenicity.

The advent of intracranial stents has revolutionized the endovascular treatment of cerebral aneurysms. The utilization of stents has rendered numerous cerebral aneurysm amenable to endovascular treatment, thereby obviating the need for otherwise invasive open surgical options. Stent placement has become a mainstream approach because of its safety and efficacy. However, further improvements are required for clinically approved devices to avoid the frequent occurrence of thrombotic complications. Therefore, controlling the thrombotic complications associated with the use of devices is of significant importance. Our group has developed a unique stent coated with a 2-methacryloyloxyethyl phosphorylcholine (MPC)-based polymer. In this study, the surface characteristics of the polymer coating were verified using X-ray photoelectron spectroscopy and atomic force microscopy. Subsequently, the antithrombotic properties of the coating were evaluated by measuring platelet count and thrombin-antithrombin complex levels of whole human blood after 3 h of incubation in a Chandler loop model. Scanning electron microscopy was utilized to examine thrombus formation on the stent surface. We observed that MPC polymer-coated stents significantly reduced thrombus formation as compared to bare stents and several clinically approved devices. Finally, the coated stents were further analyzed by implanting them in the internal thoracic arteries of pigs. Angiographic imaging and histopathological examinations that were performed one week after implantation revealed that the vascular lumen was well maintained and coated stents were integrated within the vascular endothelium without inducing adverse effects. Thus, we demonstrated the efficacy of MPC polymer coating as a viable strategy for avoiding the thrombotic risks associated with neurovascular stents.

Residual inflammatory risk predicts long-term outcomes following stenting for symptomatic intracranial atherosclerotic stenosis

Background and purposeResidual inflammatory risk (RIR) can predict the unfavourable outcomes in patients with minor ischaemic stroke. However, the impact of preprocedural RIR on long-term outcomes in patients with symptomatic...

DRug-coated Balloon for Endovascular treatment of sYmptOmatic intracraNial stenotic Disease (DR. BEYOND): the protocol of a multicentre randomised trial

BackgroundAlthough endovascular stenting is considered an effective and safe therapeutic option for symptomatic intracranial atherosclerotic disease (sICAD), an elevated rate of restenosis remains an important issue for the conventional bare-metal...

Correlation between lipoprotein(a) and recurrent ischemic events post-cerebral vascular stent implantation

Background and aimThe association of Lipoprotein(a) (Lp[a]) with recurrent ischemic events in stented patients remains uncertain. So, this research aimed to investigate the impact of elevated Lp(a) levels on the occurrence of ischemic events in this specific patient population. MethodsTotally 553 patients who underwent intracranial or extracranial artery stent implantation were included. Baseline data were collected and postoperative ischemic outcomes were followed up. Cox regression analysis was used to investigate the association between Lp(a) and outcomes, while accounting for confounding factors. Finally, we established prediction models based on nomogram. ResultsOf total 553 patients, a number of 107 (19.3%) experienced outcomes. These included 46 cases (25.4%) in group with elevated Lp(a) levels (>30 mg/dL) and 61 cases (16.4%) in non-elevated group (χ2=6.343, p=0.012). The group with elevated Lp(a) was 1.811 times more likely to experience ischemic events than the non-elevated group, each 1 mg/dL increase in Lp(a) resulted in a 1.008-fold increase in the recurrence rate of ischemic events. In addition, sex (male), previous history of coronary heart disease, decreased albumin, elevated very low density lipoprotein cholesterol and poorly controlled risk factors (including blood pressure and blood sugar) were also associated with a high risk of recurrent ischemic events after stent implantation. ConclusionLp(a) elevation was a significant risk factor for ischemic events in symptomatic patients who underwent intracranial or extracranial artery stenting.

Spontaneous calcified cerebral emboli: a comprehensive review and proposed diagnostic criteria.

Spontaneous calcified cerebral emboli (SCCE) secondary to aortic valve calcification are a rare and underreported cause of acute ischaemic stroke. Only five cases of SCCE secondary to bicuspid aortic valve calcification have been reported in the literature. This review includes a unique case example of acute ischaemic stroke secondary to SCCE, as the first manifestation of a calcified bicuspid aortic valve. This is the first clinical case of calcified cerebral emboli (CCE) associated with borderzone infarction ('cortical ribbon sign'). Whilst previously assumed that most CCE are secondary to iatrogenic causes, recent literature suggests the majority of CCE are spontaneous and clinically silent. Despite CT imaging widely considered the 'gold standard' for diagnosis, CCE are frequently misdiagnosed and missed entirely. Misdiagnosis of CCE may have catastrophic consequences due to the high risk of recurrence and missed opportunity to prevent neurological disability and death. This review presents a revised CCE diagnostic criteria, using evidence that has emerged over the last decade to create both Compulsory (Major) and Supporting (Minor) criteria. Current CCE management is not evidence based and remains largely speculative. SCCE may be the first manifestation of cardiac or vascular disease and diagnosis should trigger aggressive treatment of emboligenic sources. Future epidemiological studies, analysing symptomatic and asymptomatic SCCE patients, would be beneficial in providing accurate quantification of disease burden. Other future research directions include exploring intracranial stenting for CCE revascularisation and cerebral intravascular lithotripsy.

Comprehensive Assessment of Drug Kinetics, Neurotoxicity, and Safety of Sirolimus-Eluting Intracranial Stents in Canine Basilar Artery.

Sirolimus-eluting stents (SESs) have shown promise in treating intracranial atherosclerosis but concerns about potential neurotoxicity due to prolonged drug release exist. The aim of this study was to comprehensively assess the safety of SES, with a focus on neurotoxicity. Stents (1.50 × 7 or 12 mm) were implanted into the basilar arteries of 154 Labrador Retrievers (weighing >25 kg and aged older than 1 year) divided into 4 groups: baer-metal stent, polymer-coated stent, standard-dose SES (sirolimus dose: 71 μg), and high-dose SES group (sirolimus dose: 284 μg). Pharmacokinetic analysis was conducted using liquid chromatography-mass spectrometry on blood and tissue samples, and analysis of brain tissue was performed with 5 different special stains and immunohistochemistry protocols to assess axonal degeneration, vacuolization, astrocyte proliferation, microglial activation, or widespread neurodegeneration. In the standard-dose SES group, the stent released 10.56% of the drug on day 1 and 95.41% on day 28 postimplantation. In the high-dose SES group, corresponding figures were 40.20% on day 1 and 98.08% on day 28. Systemic drug concentration consistently remained below 1.5 ng/mL throughout the study. Arterial tissue concentration reached its peak at day 28 days in the standard-dose group and at 7 days in the high-dose group. Importantly, the brain and related tissue concentrations remained below 0.4 µg/g in both standard-dose and high-dose SES groups, peaking on day 21 in the standard-dose group and day 1 in the high-dose group. The detailed 180-day safety assessment revealed no adverse effects on the brain, even at high sirolimus doses in the SES group. This study provides robust evidence supporting the long-term pharmacokinetic safety of SESs in the context of intracranial interventions for high-grade intracranial atherosclerosis. The results adequately alleviate concerns related to neurotoxicity and substantiate the feasibility of using these stents as a therapeutic choice in neurosurgery.

Self-expanding intracranial drug-eluting stent system in patients with symptomatic intracranial atherosclerotic stenosis: initial experience and midterm angiographic follow-up.

Symptomatic intracranial atherosclerotic stenosis (ICAS) is a major cause of ischemic stroke worldwide. In patients undergoing endovascular treatment for ICAS, in-stent restenosis (ISR) is associated with ischemic stroke recurrence. Intracranial drug-eluting self-expanding stent systems (COMETIU; Sinomed Neurovita Technology Inc., CHN) are new devices for treating ICAS. This study evaluated the perioperative experience and medium-term outcomes of COMETIU in 16 patients. We prospectively analyzed 16 patients with ICAS (≥ 70% stenosis) who underwent intravascular therapy between September 4, 2022, and February 1, 2023. The primary outcome was the incidence of ISR at 6 months postoperatively. The secondary efficacy outcomes were device and technical success rates. The secondary safety outcomes included stroke or death within 30 days after the procedure and the cumulative annual rate of recurrent ischemic stroke in the target-vessel territory from 31 days to 6 months and 1 year. A total of 16 patients with 16 intracranial atherosclerotic lesions were treated with 16 COMETIUs. All procedures were performed under general anesthesia with 100% device and technical success rates, with no cases of periprocedural stroke or death. The mean radiographic follow-up duration was at least 6 months postoperatively, and all patients presented for radiographic and clinical follow-up. There were no reported ischemic or hemorrhagic strokes. Angiographic follow-up for all patients revealed no cases of ISR. COMETIU is safe and effective for treating ICAS, with minimal risk during the procedure and a low rate of ISR during medium-term follow-up.

Prevalence and Angiographic Outcomes of Rescue Intracranial Stenting in Large Vessel Occlusion Following Stroke Thrombectomy – STRATIS

BACKGROUND Large vessel occlusion secondary to underlying intracranial atherosclerotic disease (ICAD‐LVO) has an estimated prevalence of 7% to30%. There is a large variation in the use of intracranial rescue stenting in interventional practice. We aimed to characterize the frequency and characteristics of intracranial rescue stenting in a large cohort of endovascular therapy for stroke. METHODS The Systematic Evaluation of Patients Treated With Stroke Devices for Acute Ischemic Stroke (STRATIS) angiography core lab adjudicated the location of the occlusion, hyperdense vessel sign on initial imaging, the use of angioplasty and stenting, and imaging outcomes following endovascular therapy. Underlying cause of stroke was categorized into intracranial atherosclerosis, cardioembolic, and other subtypes. Statistical analyses examined the relationship between intracranial rescue stenting and imaging outcomes including intracranial hemorrhage, and arterial reperfusion using expanded Thrombolysis in Cerebral Infarction reperfusion score in patients with ICAD‐LVO. RESULTS Among 978 patients with LVO stroke undergoing endovascular therapy, 91 (9.3%) patients had ICAD‐LVO. Baseline hyperdense vessel sign was observed among 44 (62.7%) with ICAD versus 178 (68.2%) with cardioembolic LVO ( P = 0.4). Final successful reperfusion (expanded Thrombolysis in Cerebral Infarction 2b50 or more) was significantly lower among ICAD‐LVO as compared with cardioembolic‐LVO (74.2% versus 87.5%; P = 0.007). Intracranial rescue stenting was used among 14/665 (2.1%) of patients with LVO (5 ICA terminus, 7 M1 middle cerebral artery, 1 M2 middle cerebral artery, 1 proximal basilar artery). Among 14 intracranial rescue stenting cases, 5/70 (7.1%) belonged to the ICAD group, 3/261 (1.1%) cardioembolic group, and 6/334 (1.8%) in other or undetermined group. Successful reperfusion following rescue stenting was achieved in all cases with ICAD‐LVO. Among ICAD‐LVO, the rate of 24 hours symptomatic intracranial hemorrhage was 0% with acute intracranial stenting versus 7.7% in the nonstenting subgroup. CONCLUSION In STRATIS, nearly 1 of every 11 thrombectomies were performed in patients with underlying ICAD, among whom 7.1% underwent rescue intracranial stenting concomitant with thrombectomy. Acute intracranial stenting as rescue therapy in ICAD‐LVO was associated with favorable angiographic outcomes and low symptomatic hemorrhage rates.

The Role of Internal Carotid Artery Stent in the Management of Skull Base Paragangliomas.

Background: After two decades from its introduction in the lateral skull base paraganglioma surgery, the indications and results of preoperative internal carotid artery stenting should be critically assessed. Materials and Methods: Monocentric retrospective study on 26 patients affected by head and neck paragangliomas (19 tympanojugular paragangliomas, 4 carotid body paragangliomas, 3 vagal paragangliomas) preoperatively treated with internal carotid artery stents between 2008 and 2023. The preoperative findings, the intraoperative complications and the final surgical results were analyzed. Results: The stent complication rate was less than 3.1%. Self-expanding highly flexible intracranial nitinol stents were applied. In all cases, it was possible to completely mobilize the internal carotid artery and perform a vascular dissection of the tumor. Gross total tumor resection was possible in 85% of cases. The median follow up was 7.83 y (SD +/- 3.93 y). No local recurrence was observed. Conclusions: The preoperative vascular stent facilitates tumor dissection from the internal carotid artery without risk of vascular damage, helping the surgeon to achieve surgical radicality. The vascular stent is indicated in the case of revision surgeries, circumferential involvement of the vessel and in cases with non-insufficient intracerebral crossflow. Procedural complications, temporary antiplatelet therapy and delay of surgery are the limitations of the procedure.

A Long-Term Outcome of Symptomatic Middle Cerebral Artery Undergoing Intracranial Angioplasty or Stenting

PurposeFor symptomatic stenosis in the middle cerebral artery (MCA), intracranial angioplasty and stenting are frequently employed. However, limited data exist regarding their long-term impact. Our study demonstrates the long-term advantages in preventing ischemic events through a 5-year follow-up period. MethodsA set of 41 individuals with symptomatic stenosis in the central cerebral artery (MCA) who underwent angioplasty or stenting procedures between October 2004 and April 2018 at various hospitals in Southwest China were prospectively enrolled in the study. The rates of successful revascularization, complications, imaging observations, and clinical outcomes were systematically assessed. ResultsA total of 41 individuals successfully underwent stenting , respectively. After stenting, the extent of stenosis was decreased from 71.8 percent (56 -87.8%) to 24.9 percent (0-45 percent). The mean of follow period is 36.9 ± 13.68 months (range , 11-67 months). There was no deterioration of neurological function or a new ischemic event. A DSA or CTA was conducted after the procedure and demonstrated no in-stent restenosis. No patient experienced restenosis below 50% during the mean follow-up period. The morbidity and mortality rates of the case series were 7.3% and 2.4%, respectively. ConclusionIn the treatment of symptomatic MCA atherosclerotic stenoses, intracranial angioplasty & stenting are demonstrated to be technically feasible and safe. Its early & long-term efficacy on ischemic event prevention is acceptable, with a reduced level of restenosis, although the representative sample is tiny.

Diluted contrast media combined with high-resolution C-arm CT for evaluating apposition of flow diversions in a porcine model.

In intracranial stenting, good stent apposition is crucial, and high-resolution C-arm computer tomography (CT) is utilized to assess whether stent apposition is complete. This study was aimed at finding optimal hypertonic or isotonic contrast media injection concentration for high-resolution C-arm CT to assess apposition of flow diversion (FD) after carotid artery stenting in swine. Twelve FD stents were implanted into the left carotid artery of Bama swine through the endovascular method. During high-resolution C-arm CT scanning, 6%, 8%, 10%, 12%, and 14% dilution percentages of hypertonic contrast media (iopromide 370 mg/ml) and 10%, 12%, 14%, 16%, and 18% dilution percentages of isotonic contrast media (iodixanol 320 mg/ml) were separately injected. A radiologist and a neuro-interventional specialist evaluated and qualitatively scored the post-processed images, and intravascular ultrasound (IVUS) was used to verify the accuracy of these images. Overall, 12 FD stents were implanted into the left common carotid artery of 12 swine, with a technical success rate of 100%. The best reconstructed images used to observe stent apposition were achieved with iopromide diluted to a concentration of 12% (all P < .05) or iodixanol diluted to a concentration of 16% (all P < .05). Malapposition was noted in one case, and good apposition was noted in 11 cases. These results were consistent with IVUS observations. Injecting iopromide or iodixanol diluted to 12% or 16% during high-resolution C-arm CT scanning, respectively, can help evaluate FD stent apposition and obtain optimal image quality.

Active drug-coated flow diverter in a preclinical model of intracranial stenting

BackgroundFlow diverters carry the risk of thromboembolic complications (TEC). We tested a coating with covalently bound heparin that activates antithrombin to address TEC by locally downregulating the coagulation cascade. We...

Appraisal of the Flow Diversion Effect Provided by Braided Intracranial Stents.

Objective: Comparison of the results of stent-assisted coiling (SAC) with braided stents (BS), flow diverters (FD), and laser-cut stents (LCS) to determine the relative flow-diverting capacity of BS (Leo baby and Accero). Methods: Saccular intracranial aneurysms treated by SAC and FD-assisted coiling were retrospectively evaluated. Aneurysm occlusion, as graded per Raymond-Roy score, was categorized as either recanalization/stable residual filling (Group A; lacking a flow diversion effect) or stable/progressive occlusion (Group B with a "flow diversion effect"). Factors predicting the flow diversion effect were evaluated. Results: Of the 194 aneurysms included, LCS, BS, and FD were used in 70 (36.1%), 86 (44.3%), and 38 (19.6%) aneurysms, respectively. Aneurysms treated by FD were larger, had wider necks, and were located on larger parent arteries (p < 0.01, 0.02, and <0.01, respectively). The mean imaging follow-up duration was 24.5 months. There were 29 (14.9%) aneurysms in Group A and 165 (85.1%) in Group B. Among a spectrum of variables, including sex, age, aneurysm size, neck width, parent artery diameter, follow-up duration, and stent type, the positive predictors for stable/progressive aneurysm occlusion were aneurysm size and placement of an FD or BS (p < 0.01 and p < 0.01, respectively, and were positive predictors over LCS: ORs 6.34 (95% CI: 1.62-24.76) and 3.11 (95% CI: 1.20-8.07), respectively) in multivariate analysis. Conclusions: The placement of BS was a predictor of flow diversion over laser-cut stents. However, the flow diversion effect was approximately half that of FDs, suggesting that BS may only be considered to have some (partial) flow diversion effects.