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Introduction: Understanding clot composition and associated genomic, epigenomic, and proteomic signatures could provide insight into thrombus biology and etiology, and aid in prognosis in stroke. We report preliminary analysis of histology evaluations in subjects enrolled in the INSIGHT Registry, a multicentered ‘multi-omic’ analysis of thrombi associated with acute hemorrhagic and ischemic stroke this multi-omic clot collection registry. Our aim was to determine potential histology differences in thrombi as a consequence of infarct time (time from last known normal to thrombectomy). Material and Methods: Subjects age ≥18 years, treated frontline with the Penumbra System for thrombectomy are included in this analysis. Patient demographics, medical history, radiographic, and procedural information are collected in conjunction with extracted clot and concurrent extracranial arterial blood. Enrollment, data collection, and data monitoring are ongoing for the INSIGHT registry. While the protocol includes analysis for proteomics and transcriptomics, for this analysis we used automated histology. An MSB Trichrome stain was used to evaluate the tissue. Composition was determined by automated pixel analysis, with the values representing ratios of the overall clot. Results: Samples from 60 subjects who were enrolled from 10 sites between 02/2021 and 07/2021. Analysis of the thrombi successfully determined the relative portions of fibrin, red blood cells (RBCs), and platelets (PLT). The median percentage of fibrin in the thrombi was 44.0% (IQR 29.0 - 57.6; N=60). The median time interval from Last Known Well to recanalization was 4.0 hours (IQR 2.9-12.8 hours; N=55). There was no correlation between the time interval of stroke and the percent of fibrin in the thrombus (Pearson correlation coefficient -0.01, p 0.94). Conclusion: These preliminary results demonstrate a lack of relationship between time interval of the stroke and clot histology composition with relation to fibrin. Thrombus fibrin composition is likely more related to other factors, and not predominantly related to time. We are currently investigating potential relationships to demographics and co-morbidities.

© 2018 Elsevier B.V. As we progress in into a digital era where most aspects of our life depend upon a network of computers, it is essential to focus on digital security. Each component of a network, be it a physical network, virtual network or social network requires security when transmitting data. Hence the dynamic wireless mesh network must also deploy high levels of security as found in current legacy networks. This paper presents a secure Geo-Location Oriented Routing (Secure-GLOR) protocol for wireless mesh networks, which incorporates a hybrid encryption scheme for its multilevel security framework. The hybrid encryption technique improves the network's overall performance compared to the basic encryption by using a combination of symmetric key as well as asymmetric key encryption. Using the combination of the two encryption schemes, the performance of the network can be improved by reducing the transmitted data size, reduced computational overhead and faster encryption–decryption cycles. In this paper discussed multiple encryption schemes for both symmetric and asymmetric encryption, compare their performance in various experimental scenarios. Proposed security scheme achieves better performance based on the results obtained with most viable options for our network model.

This meeting abstract was removed due to the OA licensing requirements of this journal. The full abstract is listed here : https://www.svin.org/files/SVIN_2021_Abstracts_for_Web.pdf

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 registry requiring ≥75% Penumbra Coils, including SMART, PC400, and/or POD coils. The primary efficacy endpoint was retreatment rate at 1-year and the primary safety endpoint was the procedural device-related serious adverse event rate.Results: Between June 2016 and August 2018, 995 patients (mean age 59.6 years, 72.1% female) were enrolled at 68 sites in the U.S. and Canada. Target lesions were intracranial aneurysms in 91.0% of patients; 63.5% were wide-neck and 31.8% were ruptured. Adjunctive devices were used in 55.2% of patients. Mean packing density was 32.3%. Procedural device-related serious adverse events occurred in 2.6% of patients. The rate of immediate post-procedure adequate occlusion was 97.1% in aneurysms and the rate of complete occlusion was 85.2% in non-aneurysms. At 1-year, the retreatment rate was 6.8%, Raymond Roy Occlusion Classification (RROC) I or II was 90.0% for aneurysms, and Modified Rankin Scale (mRS) 0-2 was achieved in 83.1% of all patients. Predictors of 1-year for RROC III or retreatment (incomplete occlusion) were rupture status (P < 0.0001), balloon-assisted coiling (P = 0.0354), aneurysm size (P = 0.0071), and RROC III immediate post-procedure (P = 0.0086) in a model that also included bifurcation aneurysm (P = 0.7788). Predictors of aneurysm retreatment at 1-year was rupture status (P < 0.0001).Conclusions: Lesions treated with SMART System coils achieved low long-term retreatment rates.Clinical Trial Registration:https://www.clinicaltrials.gov/, identifier NCT02729740.

Background and Purpose— Mechanical thrombectomy (MT) devices have led to improved reperfusion and clinical outcomes in acute ischemic stroke patients with emergent large vessel occlusions; however, less than one-third of patients achieve complete reperfusion. Use of intraarterial thrombolysis in the context of MT may provide an opportunity to enhance these results. Here, we evaluate the use of intraarterial rtPA (recombinant tissue-type plasminogen activator) as rescue therapy (RT) after failed MT in the North American Solitaire Stent-Retriever Acute Stroke registry. Methods— The North American Solitaire Stent-Retriever Acute Stroke registry recruited sites within North America to submit data on acute ischemic stroke patients treated with the Solitaire device. After restricting the population of 354 patients to use of RT and anterior emergent large vessel occlusions, we compared patients who were treated with and without intraarterial rtPA after failed MT. Results— A total of 37 and 44 patients was in the intraarterial rtPA RT and the no intraarterial rtPA RT groups, respectively. Revascularization success (modified Thrombolysis in Cerebral Infarction ≥2b) was achieved in more intraarterial rtPA RT patients (61.2% versus 46.6%; P =0.13) with faster times to recanalization (100±85 versus 164±235 minutes; P =0.36) but was not statistically significant. The rate of symptomatic intracranial hemorrhage (13.9% versus 6.8%; P =0.29) and mortality (42.9% versus 44.7%; P =0.87) were similar between the groups. Good functional outcome (modified Rankin Scale score of ≤2) was numerically higher in intraarterial rtPA patients (22.9% versus 18.4%; P =0.64). Further restriction of the RT population to M1 occlusions only and time of onset to groin puncture ≤8 hours, resulted in significantly higher successful revascularization rates in the intraarterial rtPA RT cohort (77.8% versus 38.9%; P =0.02). Conclusions— Intraarterial rtPA as RT demonstrated a similar safety and clinical outcome profile, with higher reperfusion rates achieved in patients with M1 occlusions. Prospective studies are needed to delineate the role of intraarterial thrombolysis in MT.

Edge computing is an emerging research area to incorporate cloud computing into edge network devices. An Edge datacenter, also referred to as EDC, processes data streams and user requests in real-time and is therefore used to decrease the latency and congestion in the network. EDC is usually setup as a distributed system and is accordingly placed between the cloud datacenter and the data source. These EDCs work as an intermediate layer in the fog hierarchy between IoT and Cloud datacenter. EDC’s are aided by load balancers, responsible for distributing the workload amongst multiple EDC, in order to optimize resource utilization and response time. The load balancers make sure that the workload is equally divided amongst the available EDCs to avoid over loading of some EDCs while other remain idle as this directly impacts the user response and real-time event detection. Given the fact that EDCs are deployed in remote environments, the need for secure authentication is of major importance. In this paper we propose a novel load balancing technique that enables EDC authentication as well as identification of idle EDCs for better load balancing. The proposed load balancing technique is also compared with existing approaches and proves to be more efficient in locating EDC’s with less workload. In addition to the improved efficiency, the proposed scheme also strengthens the security of the network by incorporating destination EDC authentication.

Introduction: Despite advanced imaging and rapid recanalization, the majority of patients with large vessel occlusion (LVO) acute ischemic stroke (AIS) do not achieve functional independence at 90 days. Here, we explore the hypothesis that prolonged ischemia worsens clinical outcome beyond changes reflected in final infarct size, particularly in elderly patients. Methods: From the prospective, multicenter COMPLETE (Penumbra, Inc) registry, patients were included if they underwent endovascular therapy (EVT) for anterior circulation LVO, achieved TICI 2b/3 reperfusion, and EVT began within 90 minutes of imaging. Final infarct volumes (FIV) were measured on 24-48h post-EVT scans using ASPECTS. Multivariable logistic regression was used to determine the effect of stroke onset to hospital arrival time (OTA) on likelihood of functional independence (mRS 0-2) at 90 days, adjusting for age, NIHSS, occlusion location, pre-morbid mRS and final infarct. The effect of OTA on outcome was evaluated in older vs. younger patients using propensity score matching. Data are presented as median [IQR] or OR [95% CI]. Results: Among 302 patients, median age was 71 [61-79], NIHSS was 15 [10-20], 56% were female, median OTA was 154 [75-320]. Median FIV ASPECTS was 7 [6-8]. In multivariable analysis adjusting for FIV, longer OTA was associated with decreased likelihood of functional independence (OR 0.74 [0.57-0.96]). FIV-independent worsening with prolonged OTA was more pronounced with advanced age (Figure). Using propensity score matching, elderly patients (age > 70) matched by age, NIHSS, occlusion location and FIV were less likely to have functional independence with prolonged OTA (Coef -0.2, p Conclusions: In patients with LVO AIS who achieve successful reperfusion, delays in EVT reduce the likelihood of good clinical outcomes independent of FIV. This effect is more pronounced with advanced age.

The ability to judge accurately whether or not an action can be accomplished successfully is critical for selecting appropriate response options that enable adaptive behaviors. Such affordance judgments are thought to rely on the perceived fit between environmental properties and knowledge of one's current physical capabilities. Little, however, is currently known about the ability of individuals to judge their own affordances following a stroke, or about the underlying neural mechanisms involved. To address these issues, we employed a signal detection approach to investigate the impact of left or right hemisphere injuries on judgments of whether a visual object was located within reach while remaining still (i.e., reachability). Regarding perceptual sensitivity and accuracy in judging reachability, there were no significant group differences between healthy controls (N = 29), right brain damaged (RBD, N = 17) and left brain damaged stroke patients (LBD, N = 17). However, while healthy controls and RBD patients demonstrated a negative response criterion and thus overestimated their reach capability, LBD patients' average response criterion converged to zero, indicating no judgment tendency. Critically, the LBD group's judgment tendency pattern is consistent with previous findings in this same sample on an affordance judgment task that required estimating whether the hand can fit through apertures (Randerath et al., 2018). Lesion analysis suggests that this loss of judgment tendency may be associated with damage to the left insula, the left parietal and middle temporal lobe. Based on these results, we propose that damage to the left ventro-dorsal stream disrupts the retrieval and processing of a stable criterion, leading to stronger reliance on intact on-line body-perceptive processes computed within the preserved bilateral dorsal network. published

The current era of technology is flooded with hundreds of Internet of Things (IoT) applications with billions of IoT objects. One of the primary applications is healthcare systems, where body area network (BAN)-sensing healthcare devices (such as leg movement sensor, heart-rate sensing, etc.) collect the user's real-time data (such as heart rate, step counts, and many more). These real-time users’ data are vulnerable to various attacks related to authentication. It may also create scope for further attacks exploiting authentication. Therefore it requires a proper authentication mechanism and should be transmitted securely without compromising the privacy of the user's healthcare information. Moreover, these devices are very much computationally resource constrained. This chapter emphasizes the afore-mentioned threats and constraints, and proposes a secure, lightweight authentication protocol between a healthcare wearable device and its user. The scheme uses a cryptographic hash function and X-OR functionalities only. It is tested by a well-known formal security verification tool, AVISPA, to show its robustness against various attacks related to authentications. The secure establishment of a shared secret key is also shown by the well-known BAN authentication logic. Furthermore, the computational cost of the scheme is also computed and compared with other work to prove its efficiency.

Background and Purpose— In acute ischemic stroke, fast and complete recanalization of the occluded vessel is associated with improved outcomes. We describe a novel measure for newer generation devices: the first pass effect (FPE). FPE is defined as achieving a complete recanalization with a single thrombectomy device pass. Methods— The North American Solitaire Acute Stroke Registry database was used to identify a FPE subgroup. Their baseline features and clinical outcomes were compared with non-FPE patients. Clinical outcome measures included 90-days modified Rankin Scale score, National Institutes of Health Stroke Scale score, mortality, and symptomatic intracranial hemorrhage. Multivariate analyses were performed to determine whether FPE independently resulted in improved outcomes and to identify predictors of FPE. Results— A total of 354 acute ischemic stroke patients underwent thrombectomy in the North American Solitaire Acute Stroke registry. FPE was achieved in 89 out of 354 (25.1%). More middle cerebral artery occlusions (64% versus 52.5%) and fewer internal carotid artery occlusions (10.1% versus 27.7%) were present in the FPE group. Balloon guide catheters were used more frequently with FPE (64.0% versus 34.7%). Median time to revascularization was significantly faster in the FPE group (median 34 versus 60 minutes; P =0.0003). FPE was an independent predictor of good clinical outcome (modified Rankin Scale score ≤2 was seen in 61.3% in FPE versus 35.3% in non-FPE cohort; P =0.013; odds ratio, 1.7; 95% confidence interval, 1.1–2.7). The independent predictors of achieving FPE were use of balloon guide catheters and non-internal carotid artery terminus occlusion. Conclusions— The achievement of complete revascularization from a single Solitaire thrombectomy device pass (FPE) is associated with significantly higher rates of good clinical outcome. The FPE is more frequently associated with the use of balloon guide catheters and less likely to be achieved with internal carotid artery terminus occlusion.

© 2002-2012 IEEE. The Internet of Things (IoT) is an emerging technology that has gained a huge user base by facilitating Internet-connected devices being used in numerous applications including smart vehicular infrastructure. In this context, we focus on the traditional vehicular ad hoc network that has evolved into a new perception called the Internet of Vehicles (IoV), and is expected to soon transform into the Internet of Autonomous Vehicles (IoAV). IoAV hopes to facilitate smart vehicular infrastructure and autonomous driving without the need for human involvement. However, as the number of connected vehicles keeps increasing, so does the need for autonomous decision making. Hence, the IoAV must provide robust, secure, seamless, and scalable communication among the vehicles as well as the roadside units. This article provides an overview of autonomous vehicle communication layers, its associated properties, and security threats. Further, this article also briefly discusses the current research trends and future research issues.

Background and Purpose- Mechanical thrombectomy (MT) devices have led to improved reperfusion and clinical outcomes in acute ischemic stroke patients with emergent large vessel occlusions; however, less than one-third of patients achieve complete reperfusion. Use of intraarterial thrombolysis in the context of MT may provide an opportunity to enhance these results. Here, we evaluate the use of intraarterial rtPA (recombinant tissue-type plasminogen activator) as rescue therapy (RT) after failed MT in the North American Solitaire Stent-Retriever Acute Stroke registry. Methods- The North American Solitaire Stent-Retriever Acute Stroke registry recruited sites within North America to submit data on acute ischemic stroke patients treated with the Solitaire device. After restricting the population of 354 patients to use of RT and anterior emergent large vessel occlusions, we compared patients who were treated with and without intraarterial rtPA after failed MT. Results- A total of 37 and 44 patients was in the intraarterial rtPA RT and the no intraarterial rtPA RT groups, respectively. Revascularization success (modified Thrombolysis in Cerebral Infarction ≥2b) was achieved in more intraarterial rtPA RT patients (61.2% versus 46.6%; P=0.13) with faster times to recanalization (100±85 versus 164±235 minutes; P=0.36) but was not statistically significant. The rate of symptomatic intracranial hemorrhage (13.9% versus 6.8%; P=0.29) and mortality (42.9% versus 44.7%; P=0.87) were similar between the groups. Good functional outcome (modified Rankin Scale score of ≤2) was numerically higher in intraarterial rtPA patients (22.9% versus 18.4%; P=0.64). Further restriction of the RT population to M1 occlusions only and time of onset to groin puncture ≤8 hours, resulted in significantly higher successful revascularization rates in the intraarterial rtPA RT cohort (77.8% versus 38.9%; P=0.02). Conclusions- Intraarterial rtPA as RT demonstrated a similar safety and clinical outcome profile, with higher reperfusion rates achieved in patients with M1 occlusions. Prospective studies are needed to delineate the role of intraarterial thrombolysis in MT.

Background: Various techniques are used to enhance the results of mechanical thrombectomy with stent-retrievers, including proximal arrest with balloon guide catheter (BGC), conventional large bore proximal catheter (CGC), or in combination with local aspiration through a large-bore catheter positioned at the clot interface (Aspiration-Retriever Technique for Stroke [ARTS]). We evaluated the impact of ARTS in the North American Solitaire Acute Stroke (NASA) registry. Summary: Data on the use of the aspiration technique were available for 285 anterior circulation patients, of which 29 underwent ARTS technique, 131 CGC, and 125 BGC. Baseline demographics were comparable, except that ARTS patients are less likely to have hypertension or atrial fibrillation. The ARTS group had more ICA occlusions (41.4 vs. 22% in the BGC, p = 0.04 and 26% in CGC, p = 0.1) and less MCA/M1 occlusions (44.8 vs. 68% in BGC and 62% in CGC). Time from arterial puncture to reperfusion or end of procedure with ARTS was shorter than with CGC (54 vs. 91 min, p = 0.001) and was comparable to the BGC time (54 vs. 67, p = 0.11). Final degree of reperfusion was comparable among the groups (TICI [modified Thrombolysis in Cerebral Infarction] score 2b or higher was 72 vs. 70% for CGC vs. 78% for BGC). Procedural complications, mortality, and good clinical outcome at 90 days were similar between the groups. Key Messages: The ARTS mechanical thrombectomy in acute ischemic stroke patients appears to yield better results as compared to the use of CGCs with no significant difference when compared to BGC. This early ARTS technique NASA registry data are limited by the earlier generation distal large bore catheters and small sample size. Future studies should focus on the comparison of ARTS and BGC techniques.