Richard Bellon's research while affiliated with Swedish Medical Center and other places

Publications (53)

Article
Background: The Penumbra SMART COIL System includes a novel generation of embolic coils composed of complex and WAVE shape properties with varying levels of softness. Objective: To assess safety and efficacy of the SMART COIL System through a 1-year follow-up in patients with small intracranial aneurysms. Methods: This subset analysis of the S...
Article
Full-text available
Introduction Wide-necked middle cerebral artery bifurcation aneurysms pose specific challenges to endovascular management. Surgical clipping remains the standard treatment approach for these aneurysms in many centers. While recent data suggests the endovascular treatment may be comparable, a prospective datapoint has been lacking. Materials and Me...
Article
Full-text available
BACKGROUND Rupture status and presence of a wide neck are important factors that adversely impact angiographic occlusion after endovascular coiling. A potential strategy to improve occlusion rates in wide‐necked, ruptured aneurysms (WNRA) is modification of coil technology. METHODS WNRA were chosen from the SMART registry that comprises 905 intrac...
Article
Introduction : The purpose of this study was to assess the long‐term clinical outcomes of anterior communicating artery (ACoA) aneurysm treated with coiling. Methods : Data on patients with an ACoA aneurysm were extracted from a prospective multicenter registry (SMART) that enrolled patients with intracranial aneurysms or other neurovascular abnorm...
Article
Introduction : The purpose of this study was to assess the 1‐year clinical outcomes of wide‐necked ruptured aneurysms treated with coiling. Methods : Data on patients with a wide‐necked ruptured aneurysm were extracted from a prospective multicenter registry (SMART) that enrolled patients with intracranial aneurysm or other neurovascular abnormalit...
Article
Background and Purpose The purpose of the COMPLETE (International Acute Ischemic Stroke Registry With the Penumbra System Aspiration Including the 3D Revascularization Device) registry was to evaluate the generalizability of the safety and efficacy of the Penumbra System (Penumbra, Inc, Alameda) in a real-world setting. Methods COMPLETE was a glob...
Conference Paper
Introduction Treatment of posterior circulation aneurysm has high rates of morbidity and mortality. Aim of the Study Evaluate the safety and performance of the SMART COIL System through 1-year follow-up in posterior circulation aneurysm patients enrolled in the SMART registry. Methods This study is a subset analysis of the SMART registry, a prosp...
Conference Paper
Introduction/Purpose The purpose of this analysis was to evaluate the safety and performance of the SMART COIL System through one year of follow-up in patients with posterior aneurysms enrolled in the SMART registry. Materials and Methods The SMART registry is a prospective, multi-center registry study of subjects treated with SMART COIL, Penumbra...
Article
Objective SMART (A prospective, multicenter registry assessing the embolization of neurovascular lesions using the Penumbra SMART COIL® System) is the largest prospective, multicenter, post-market registry established to gather real-world experience on Penumbra SMART COIL® (SMART), PC400TM (PC400), and POD® (POD) embolization coils. The goal of thi...
Article
Full-text available
Introduction: Penumbra SMART COIL® (SMART) System is a novel generation embolic coil with varying stiffness. The study purpose was to report real-world usage of the SMART System in patients with intracranial aneurysms (ICA) and non-aneurysm vascular lesions. Materials and Methods: The SMART Registry is a post-market, prospective, multicenter regist...
Article
Full-text available
Background Stent-assisted coiling of wide-necked intracranial aneurysms (IAs) using the Neuroform Atlas Stent System (Atlas) has shown promising results. Objective To present the primary efficacy and safety results of the ATLAS Investigational Device Exemption (IDE) trial in a cohort of patients with posterior circulation IAs. Methods The ATLAS t...
Article
Introduction: We report the durability of treatment with SMART COIL System at one-year in patients with ruptured aneurysms enrolled in the SMART registry. Materials and Methods: The SMART Registry is a prospective, multi-center registry study. Procedures must employ ≥75% of the SMART, PC400, or POD coils to meet registry criteria. Patients with rup...
Article
Full-text available
Background Using data from the SMART registry, we report on periprocedural safety of the Penumbra SMART Coil System for endovascular coil embolization of saccular intracranial aneurysms. Methods The SMART registry was a prospective, multi-center registry of site standard of care endovascular coiling procedures performed using at least 75% Penumbra...
Article
Background Catheter retention and difficulty in retrieval have been observed during embolization of brain arteriovenous malformations (bAVMs) with the Onyx liquid embolic system (Onyx). The Apollo Onyx delivery microcatheter (Apollo) is a single lumen catheter designed for controlled delivery of Onyx into the neurovasculature, with a detachable dis...
Conference Paper
Introduction The Penumbra SMART COIL® System includes a novel generation of embolic coils comprising complex and WAVE shape properties with varying levels of softness to promote dense packing and durable long-term occlusion. We present the final analysis of 997 patients at 68 U.S./Canada sites with up to 1-yr follow-up in the SMART registry to asse...
Article
Full-text available
Background and Purpose Stent-assisted coil embolization using the new generation Neuroform Atlas Stent System has shown promising safety and efficacy. The primary study results of the anterior circulation aneurysm cohort of the treatment of wide-neck, saccular, intracranial, aneurysms with the Neuroform Atlas Stent System (ATLAS trial [Safety and E...
Article
Object: Cerebral venous thrombosis (CVT) is a rare type of stroke whose pathophysiology differs from arterial stroke. CVT is treated with systemic anticoagulant therapy even in the setting of intracerebral hemorrhage. Patients who do not respond adequately may require decompressive surgery. The study objective was to examine the timing of anticoag...
Conference Paper
Introduction The Penumbra SMART COIL System includes a novel generation of embolic coils comprised of complex and WAVE shape properties with varying levels of softness to promote dense packing and durable long-term occlusion. We report a subset analysis to assess the durability of treatment with SMART COIL System at one year follow-up in patients w...
Article
Introduction: The Penumbra SMART COIL System includes a novel generation of embolic coils comprised of complex and WAVE shape properties with varying levels of softness to promote dense packing and durable long-term occlusion. We report an interim analysis of the first 500 patients enrolled in the SMART registry to assess the utility of the SMART C...
Article
Background: CT perfusion (CTP) and diffusion or perfusion MRI might assist patient selection for endovascular thrombectomy. We aimed to establish whether imaging assessments of irreversibly injured ischaemic core and potentially salvageable penumbra volumes were associated with functional outcome and whether they interacted with the treatment effe...
Article
Background: Evidence regarding whether imaging can be used effectively to select patients for endovascular thrombectomy (EVT) is scarce. We aimed to investigate the association between baseline imaging features and safety and efficacy of EVT in acute ischaemic stroke caused by anterior large-vessel occlusion. Methods: In this meta-analysis of in...
Conference Paper
Background In order to maximize clinical outcomes in patients with acute ischemic stroke related to ELVO (Emergent Large Vessel Occlusion), safe and rapid recanalization is necessary. Our level 1 stroke center has developed a standardized protocol which has allowed us to achieve a median door-to-recanalization time of less than 60 min. In order to...
Article
Background and purpose The purpose of this study was to assess the initial post-market experience of the device and how it is compared with the Penumbra Pivotal trial used to support the 510k application. Methods A retrospective case review of 157 consecutive patients treated with the Penumbra system at seven international centers was performed. P...
Conference Paper
Introduction Smart Coils are novel generation of embolic coils comprised of complex and WAVE shape properties with varying levels of softness to promote dense packing and durable long-term occlusion. We report results from interim analysis on utility of the Penumbra Smart Coil System in the treatment of a variety of intracranial vascular lesions, s...
Article
Introduction: Smart Coils are novel generation embolic coils designed with robust shape and multiple transitions of softness to promote dense packing and durable long term occlusion. We report data on the utility of the Penumbra Smart Coil System in treatment of a variety of intracranial vascular lesions such as aneurysms and other abnormalities. M...
Conference Paper
Introduction Endovascular therapy for cerebral aneurysms has increasingly been adopted as a viable treatment strategy for its minimally invasive but effective approach. This rising adoption has been correlated with an evolution in coil technology, including the recently FDA-cleared SMART Coil. In contrast to traditional bare metal coils, which have...
Data
Figure S1. Comparative receiver operating characteristic (ROC) curve with area under the ROC presented for the full model (Model) and the cross‐validated model (ROC1). ROC curves are presented for all patients (A, n=152) and stratified by endovascular treatment (B, n=73) or no endovascular treatment (C, n=76).
Article
Full-text available
Background Cerebral venous thrombosis is a rare cause of stroke that poses diagnostic, therapeutic, and prognostic challenges. Mainstay treatment is systemic anticoagulation, but endovascular treatment is increasingly advocated. Our objectives were to describe the epidemiology, treatment, and prognosis of 152 patients with cerebral venous thrombosi...
Article
Introduction: Despite suffering mild acute ischemic strokes (AIS, NIHSS≤7), patients have a non-zero risk of significant morbidity and mortality. Intra-arterial therapy (IAT) is clearly effective in non-mild AIS, but mild AISs have been excluded from IAT trials, limiting our understanding of their outcomes after IAT. The objective of this study was...
Article
Introduction: Patients with mild acute ischemic strokes (NIHSS ≤7, AISs) have been excluded from intra-arterial therapy (IAT) trials, limiting our understanding of their outcomes after IAT. Mild AIS with large vessel occlusions (LVOs) represent a fragile subset of mild AISs. Despite a low NIHSS, these patients can have a sudden failure of collatera...
Article
Background and purpose Intra-arterial therapy (IAT) is most effective when performed rapidly after ischemic stroke onset. However, there are limited performance benchmarks in IAT and there is a scarcity of information on how to structure an effective IAT protocol and its impact on time to treatment. The objective of our study was to detail a standa...
Article
Introduction: Traditional platinum coils used for cerebral aneurysm embolization have a uniform degree of softness throughout an individual coil's length. Recently, SMART Coils (Penumbra Inc., Alameda, CA) have been developed, which transition in softness along the length of their coils. We report the initial clinical results with this technology....
Article
Full-text available
Background Acute stroke treatment has been proven to be most effective when performed immediately. The objective of our study was to describe the steps taken to improve time metrics for patients receiving intra-arterial therapy (IAT), and compare metrics before and after implementation of interventions. Hypothesis Through streamlining the evaluati...
Article
Full-text available
Objective The safety and efficacy of intra-arterial treatment (IAT) in patients with acute ischemic stroke (AIS) due to cervical artery dissection (CeAD) has not been formally studied. The purpose of this study was twofold: first, describe a large series with CeAD treated with IAT; second, analyze outcomes with CeAD receiving IAT versus (a) CeAD no...
Article
Clinical trials confirmed the safety and efficacy of intra-arterial therapy (IAT) in the management of ischemic stroke. At a community hospital, we compared outcomes in patients aged ≥80 and patients in the age range 55-79 years receiving IAT following ischemic stroke. Data were retrospectively abstracted for ischemic stroke patients ≥55 years trea...
Article
Purpose Newer generations of devices in endovascular therapies are progressively used in the revascularization of large vessel occlusions in acute ischemic stroke. The aim of this case review study was to evaluate if there was a corresponding improvement in procedural times over the course of the evolution of these devices. Methods Procedural times...
Article
Purpose: Endovascular therapies are increasingly used in the revascularization of acute ischemic stroke from large vessel occlusions. There have been many design improvement of these devices from their initial implementation to the recent newer generations of devices. The goal of this case review study was to assess if there was corresponding impro...
Article
Introduction/Purpose We report clinical experience and long-term follow-up results in treating 24 small aneurysms in 22 patients, ranging from 2mm to 4.4mm, using the Penumbra PC400 Large Volume Coil at 4 high volume centres. Follow-ups are available for 12 aneurysms at the current time. Materials and Methods Our treatment population consisted of 2...
Article
Introduction/Purpose Aneurysm coil technology has changed considerably since the introduction of the GDC coil. We evaluated our initial clinical experience with a novel 0.020 Penumbra PC 400 coil to determine device safety and acute performance. Materials and Methods Between 2/2011 and 9/2012, 133 aneurysms were coiled with Penumbra PC 400 coils; 8...
Article
Background and purpose: Revascularization of acute ischemic stroke from a large vessel occlusion continues to be a challenge with current thrombectomy devices. The purpose of the SPEED study was to report the safety and effectiveness of the Penumbra 054 Reperfusion Catheter System in revascularizing large vessel occlusions. Methods: In this retr...
Article
Full-text available
Background The treatment of acute ischemic stroke is traditionally centered on time criteria, although recent evidence suggests that physiologic neuroimaging may be useful. In a multicenter study we evaluated the use of CT perfusion, regardless of time from symptom onset, in patients selected for intra-arterial treatment of ischemic stroke. Method...
Article
Background Traditional treatment in acute ischemic stroke is based on time criteria when administering intravenous and intra-arterial therapies. However recent evidence suggests that image based criteria may be useful for selecting patients for intra-arterial interventions. We investigated CT perfusion (CTP) based criteria, regardless of time from...
Article
Objective Conventional treatment of cerebral venous sinus thrombosis (CVT) has been systemic heparinization. A variety of endovascular treatment paradigms have been described for the treatment of symptomatic CVST that has failed conventional therapy. We retrospectively evaluated the efficacy and safety of thromboembolectomy using the Fogarty balloo...
Article
Introduction Recanalization of tandem vascular occlusions involving the cervical carotid artery and an ipsilateral intracranial large vessel is a difficult treatment challenge. These lesions have been historically observed to be refractory to most conservative medical therapies. New endovascular options have been rapidly emerging over the last few...
Article
PurposeThe 054 reperfusion catheter is a newly introduced component of the Penumbra System specifically designed to enhance aspiration efficiency by increasing the catheter diameter. The goal of this study was to compare its safety and effectiveness in reducing clot burden in the internal carotid artery (ICA) and the middle cerebral artery (MCA).Me...
Article
The purpose of this study was to assess the initial post-market experience of the device and how it is compared with the Penumbra Pivotal trial used to support the 510k application. A retrospective case review of 157 consecutive patients treated with the Penumbra system at seven international centers was performed. Primary endpoints were revascular...
Article
Purpose The extent to which acute ischemic stroke patients' functional outcome can be improved by mechanical thrombectomy remains controversial. This is due in part to the lack of appropriate control groups in trials with these devices. The purpose of this study was to assess the effect of the novel mechanical thrombectomy device, the Penumbra Syst...
Article
Full-text available
Abstract BACKGROUND AND PURPOSE: The purpose of this clinical evaluation was to assess the safety and effectiveness of the Penumbra System in the revascularization of patients presenting with acute ischemic stroke secondary to intracranial large vessel occlusive disease. METHODS: In this prospective, multicenter, single-arm study, 125 patients with...
Article
Purpose: The purpose of this study was to assess the post-market experience of the Penumbra System at several academic and community hospitals. The Penumbra System is a new generation of mechanical devices designed to reduce clot burden in acute stroke due to large vessel thromboembolism. It was recently approved for commercial use in the US and Eu...

Citations

... Endovascular and surgical treatments are available for aneurysm repair, which are the only effective treatments to prevent rebleeding at present (4). However, for some complex aneurysms, giant aneurysms and aneurysms with a low fundus-to-neck ratio, specialized skills are required to obtain satisfactory embolization, including stent-assisted coiling (SAC), balloon-assisted coiling (BAC), flow diverters (FD), and the use of new embolic materials including liquids (5)(6)(7). Stent placement has been commonly applied in acutely RIA, including classic laser-cut stents, braided stents, drug-eluting stents, and covered stents (8)(9)(10). These skills are expected to enable aneurysms previously considered unsuitable for the endovascular procedure to be treated in the future (5,11). ...
... While 90% of LVO patients achieve near complete reperfusion after EVT, at least 40% still suffer a substantial disability. 1 Ischemia and reperfusion can lead to continued injury and dysfunction at the arteriolar and capillary levels even after recanalization. Moreover, continued infarct growth is also attributed to the activation of several mechanisms and inflammatory pathways. ...
... Most of the pertinent clinical trials published in the last decade excluded patients with ASPECTS of ≤ 5, which lead treating neurointerventionalists to confront the dilemma of whether to proceed with EVT or have recourse to medical treatment in these circumstances. Patients with AS-PECTS lower than 6 were excluded from most clinical trials that validated mechanical thrombectomy indications in the last decade [8], therefore, data about their outcomes and whether they could benefit from MT remain scarce and largely undetermined [5]. Hence, patients with low AS-PECTS have been generally thought to be ineligible for EVT given the lower chance of salvaging neuronal tissue to improve functional outcome and to mitigate the risk of revascularization bleeding of infarcted tissue [9]. ...
... The SMART registry, which started in 2016, is one of the most extensive prospective cerebral aneurysm coiling studies to date and includes patients with ruptured aneurysm with severe Hunt and Hess scores. Spiotta et al (21) reported that in a study including 905 patients with cerebral aneurysm, 392 patients were treated with SC (43.3%), 184 with BAC (20.3%), and 337 with SAC (37.2%). The mean CPD was 32.3% ± 18.2. ...
... 16 The outcome of Neuroform Atlas-assisted coiling in patients with posterior circulation aneurysms was similar, with an immediate complete aneurysm occlusion rate of 77.6%. 17 In a retrospective study, Grossberg et al 18 studied the outcomes of aneurysms that were coiled with the assistance of LVIS Jr. They observed immediate complete aneurysm occlusion in 43%. ...
... It was 37.4% ± 2.1 in the present study. Likewise, Starke et al (22) reported a mean CPD of 32.3% ± 18.3 in 811 cerebral aneurysms. In the current literature (12,13,(23)(24)(25), the mean CPD ranged between 27.4% and 37.9%, although none of these studies compared CPD values among the coiling methods. ...
... How much safety is actually 'safe'? Commentary on 'Safety of the Apollo Onyx delivery microcatheter for embolization of brain arteriovenous malformations: results from a prospective post-market study' by Meyers et al Alexander Sirakov,1 Krasimir Minkin, 2 Stanimir Sirakov 1 We read with great interest the recently published article in the journal entitled 'Safety of the Apollo Onyx delivery microcatheter for the embolization of brain arteriovenous malformations: results from a prospective post-market study'. This study yielded overall fantastic technical, angiographic results with low morbidity and mortality rates. 1 The primary endpoints for which the trial was powered were clearly defined as follows: unintentional catheter tip detachment with clinical sequelae, catheter rupture/break/ fracture with clinical sequelae, or retained catheter body in the vasculature. ...
... This may be due to the smaller diameter of the distal branch vessel, which renders it more susceptible to large blood flow velocity, thereby increasing the risk of rupture [33,34]. Although wide-necked aneurysms have been defined as those with a neck width of > 4 mm, this criterion may be too absolute [35]. Blood flow through aneurysms of different-sized parent arteries may be different, even when the aneurysms have similar neck widths [35]. ...
... The optimal timing of restarting anticoagulation after hemicraniectomy is not established. A recent case series and review including 243 patients from 15 studies identified multiple approaches, though overall quality of the literature was low and reporting of early post-operative re-bleeding was heterogeneous [55]. The post-operative approach at our centre is to initiate nextday prophylactic dose of low molecular-weight heparin with daily escalation guided by repeat neuroimaging to reassess for intracranial bleeding. ...