Fouzi Bala - Academia.edu (original) (raw)

Papers by Fouzi Bala

Journal of Neuroradiology

Stroke

Background: Distal embolization (DE) is a common complication of endovascular treatment (EVT). We... more Background: Distal embolization (DE) is a common complication of endovascular treatment (EVT). We investigated the association of radiological thrombus characteristics and treatment details with DE. Methods: Patients with thin-slice (≤2.5 mm) baseline noncontrast computed tomography and computed tomography angiography from the ESCAPE-NA1 trial (Efficacy and Safety of Nerinetide for the Treatment of Acute Ischemic Stroke) were included. Thrombus annotation was performed manually on coregistered scans by experienced readers. We assessed thrombus location, distance from internal carotid artery terminus, length, perviousness, absolute attenuation, and hyperdense artery sign. In addition, we evaluated balloon guide catheter use during EVT, first-line EVT approach, the number of thrombectomy passes, and prior intravenous thrombolysis administration. DE was defined as the occurrence of emboli distal to the target artery or in new territories during EVT. The association between thrombus cha...

Computer Methods in Biomechanics and Biomedical Engineering: Imaging & Visualization

Stroke: Vascular and Interventional Neurology

Background First‐pass effect (FPE), that is, achieving reperfusion with a single thrombectomy dev... more Background First‐pass effect (FPE), that is, achieving reperfusion with a single thrombectomy device pass, is associated with better clinical outcomes in patients with acute stroke. FPE is therefore increasingly used as a marker of device and procedural efficacy. We aimed to evaluate the ability of thrombus‐based radiomics models to predict FPE in patients undergoing endovascular thrombectomy and compare performance with experts and nonradiomics thrombus characteristics. Methods Patients with thin‐slice noncontrast computed tomography and computed tomography angiography from the ESCAPE‐NA1 (Efficacy and Safety of Nerinetide for the Treatment of Acute Ischemic Stroke) trial were included. Thrombi were manually segmented on all images. Data were randomly split into a derivation set that included a training and a validation subset and an independent test set. Radiomics features were extracted from the derivation set. The machine learning models were compared with 3 expert stroke physic...

14th Congress of the European Society of Minimally Invasive Neurological Therapy 2022 Meeting Abstracts

Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques

Background: Trials of endovascular thrombectomy (EVT) for acute stroke have excluded patients wit... more Background: Trials of endovascular thrombectomy (EVT) for acute stroke have excluded patients with pre-morbid disability. We performed a meta-analysis to assess the effectiveness and safety of EVT in patients with pre-morbid disability. Methods: According to PRISMA guidelines, we searched for studies describing outcomes in patients with pre-morbid disability (modified Rankin Scale [mRS] 2-5), treated with EVT or medical management (MM). Random-effects meta-analysis was used to pool outcomes including return to baseline mRS at 90 days, symptomatic ICH (sICH), and 90-day mortality. Results: We analyzed 14 studies of patients with pre-morbid disability (mRS2-5: EVT=1,373, MM=253). Compared to medical therapy, EVT was associated with higher likelihood of return to baseline mRS (OR=2.37, 95%CI:1.39-4.04) and a trend towards lower mortality (OR=0.68, 95%CI:0.46-1.02), with similar odds of sICH (OR 1.01, 95%CI:0.49-2.08). In studies comparing patients with vs. without pre-morbid disability...

Stroke, 2022

Introduction: First-pass effect (FPE), i.e., achieving reperfusion with a single thrombectomy dev... more Introduction: First-pass effect (FPE), i.e., achieving reperfusion with a single thrombectomy device pass, is associated with better clinical outcomes in patients with acute stroke. FPE is therefore increasingly being used as a marker of device and procedural efficacy. We evaluated the ability of thrombus-based radiomics models to predict FPE in patients undergoing endovascular thrombectomy (EVT) and compare performance to experts and non-radiomics thrombus characteristics. Methods: Patients with thin-slice non-contrast CT and CT angiography from The Efficacy and Safety of Nerinetide for the Treatment of Acute Ischemic Stroke (ESCAPE-NA1) trial were included. Thrombi were manually segmented on all images. Data was randomly split into a derivation set that included a training and a validation subset and an independent test set. Radiomics features were extracted from the derivation data set. Three expert stroke physicians reviewed baseline imaging and clinical data for the test set. T...

Stroke, 2022

Background: Efficient healthcare workflow leads to faster reperfusion and better functional outco... more Background: Efficient healthcare workflow leads to faster reperfusion and better functional outcomes of stroke in the early-time window. We investigated the impact of care delays on the outcomes of stroke patients treated with endovascular thrombectomy (EVT) in the late window. Methods: Pooled data from seven randomized clinical trials and registries that only included patients who underwent EVT in the late time window (onset/last known well (LKW) time to imaging time of 6 hours or more) were combined for this analysis. The time intervals from stroke onset to successful reperfusion were analyzed. Logistic regression was used to estimate the likelihood of a functionally independent outcome at 90 days (modified Rankin scale 0-2) for each time interval while adjusting for relevant patients’ characteristics. Negative binomial regression was used to evaluate the relationship between each time interval and the predictors. Results: 584 patients were included in this analysis. The median ag...

Stroke, 2022

Background: 90-day home-time, the number of days a patient is back at their premorbid living situ... more Background: 90-day home-time, the number of days a patient is back at their premorbid living situation without an increase in level of care in the first 90 days post stroke, is routinely collected in administrative data. We evaluated the prediction of 90-day home-time using machine learning modelling in patients undergoing endovascular treatment (EVT). Methods: We used the QuICR provincial stroke registry and administrative data from Southern Alberta from Jan 2015-Dec 2019 to identify patients who underwent EVT. Imaging data were scored by 2-physician consensus. The primary outcome was 90 day home-time, which has a highly non-normal distribution with excess zero’s. We modelled using generalized boosting machine model with Gaussian distribution. Contribution of different covariates to hometime was determined using partial dependence plots. Results: We identified 659 EVT patients from Jan 2015 to Dec 2019 treated in Calgary, Alberta. Overall,median predicted 90d home-time was 41days (...

Stroke, 2022

Background: The outcome in stroke patients with ASPECTS of ≤5 who undergo Endovascular Thrombecto... more Background: The outcome in stroke patients with ASPECTS of ≤5 who undergo Endovascular Thrombectomy(EVT) in Large Vessel Occlusion (LVO) is uncertain. We used machine learning models to predict 90-day home-time in these patients. Methods: We used the QuICR provincial stroke registry and administrative data from Southern Alberta to identify patients who underwent EVT from Jan 2015-Dec 2019. Imaging data were scored by 2-physician consensus. The primary outcome was the predicted 90-day home-time(number of days a patient is back at their premorbid living situation without an increase in level of care within 90 days of the stroke) using generalized boosting machine model with Gaussian distribution. Covariate contribution to hometime was determined using partial dependence plots. Results: Of 659 EVT patients, 82(12%) had baseline ASPECTS ≤5(mean age 69.8y, 44.6% females, 93% good-moderate collaterals, M1 occlusion(64.1%). Overall, patients with low ASPECTS had lower median predicted home...

Stroke, 2022

Purpose: To validate the performance of a 3D convolutional neural network (CNN) based algorithm i... more Purpose: To validate the performance of a 3D convolutional neural network (CNN) based algorithm i.e. Stroke SENS LVO, in automatically detecting the presence of large vessel occlusions (LVO) on computed tomography angiography (CTA) images of the head. Method: A total of 400 studies (217 LVO, 183 non-LVO) were used in the analysis. The LVO group includes internal carotid artery (ICA) and m1 segment of the middle cerebral artery (M1-MCA) occlusions; and the non-LVO group includes more distal or posterior cerebral artery occlusions, no occlusions, and hemorrhagic stroke cases. Expert consensus reads were used as reference standard. Performance was evaluated using sensitivity and specificity and corresponding 95% confidence intervals (CI). Additional analysis was performed on several subgroups of interest. Results: For detecting LVO, the algorithm achieved a sensitivity of 0.894 [0.853, 0.935] and specificity of 0.874 [0.826, 0.922]. Furthermore, sensitivities of 0.857 [0.779, 0.935] on...

Stroke, 2022

Background and Purpose: Sex-related differences exist in many aspects of stroke and were mainly i... more Background and Purpose: Sex-related differences exist in many aspects of stroke and were mainly investigated in the early time window with conflicting results. However, data regarding sex disparities in late presenters are scarce. Therefore, we sought to investigate differences in outcomes between women and men treated with endovascular treatment (EVT) in the late time window. Methods: Analyses were based on the Selection Of Late-window Stroke for Thrombectomy by Imaging Collateral Extent Consortium, which was an individual-patient level analysis of seven trials and registries. Baseline characteristics, functional independence (modified Rankin Scale ≤ 2), mortality, and symptomatic intracranial hemorrhage (sICH) were compared between women and men. Effect of sex on the association between age, successful reperfusion (Thrombolysis in cerebral infarction 2b-3) and outcomes was assessed using multivariable logistic regression with interaction terms. Results: Among 608 patients treated ...

Stroke, 2022

Background and Purpose: Sex-related differences exist in many aspects of acute stroke and were ma... more Background and Purpose: Sex-related differences exist in many aspects of acute stroke and were mainly investigated in the early time window with conflicting results. However, data regarding sex disparities in late presenters are scarce. Therefore, we sought to investigate differences in outcomes between women and men treated with endovascular treatment in the late time window. Methods: Analyses were based on the SOLSTICE Consortium (Selection of Late-Window Stroke for Thrombectomy by Imaging Collateral Extent), which was an individual-patient level analysis of seven trials and registries. Baseline characteristics, 90-day functional independence (modified Rankin Scale score ≤2), mortality, and symptomatic intracranial hemorrhage were compared between women and men. Effect of sex on the association of age and successful reperfusion (final Thrombolysis in Cerebral Infarction 2b–3) with outcomes was assessed using multivariable logistic regression adjusted for age, National Institutes o...

Neuroradiology, 2021

Purpose Cortical vein opacification is not routinely assessed in patients presenting with acute i... more Purpose Cortical vein opacification is not routinely assessed in patients presenting with acute ischemic stroke (AIS), and the value of temporal assessment of venous outflow is not known. We evaluated the utility of assessing cortical venous drainage over time using multiphase CT angiography (mCTA). Methods Cortical venous drainage was assessed in patients from the Precise and Rapid Assessment of Collaterals Using Multi-Phase CTA in the Triage of Patients With Acute Ischemic Stroke for IA Therapy prospective multicenter cohort study of patients with symptoms of AIS with ICA and/or middle cerebral artery occlusion on baseline mCTA. Opacification of vein of Labbe, sphenoparietal sinus, superficial middle cerebral vein, and vein of Trolard of the affected hemisphere was graded as no (0), partial (1), or full (2) opacification in each mCTA phase. The venous opacification scores for each phase were added to generate a total venous score (TVS) (range 0-24). Primary outcome was 90-day modified Rankin score. Repeated measures analysis was used to assess the effect of phase timing on venous score on outcome. Results Of 432 patients, 284 (65.7%) had proximal arterial occlusions. Median venous opacification score per phase (range 0-8) was 3 (IQR 1-6) in the first phase and increased in the second and third phases [median (IQR): 6 (5-8) and 8 (6-8), respectively] of the mCTA. In a multivariable analysis adjusting for age, baseline National Institutes of Health Stroke Scale, and Alberta stroke program early CT score, a significant association between TVS and 90-day mRS was noted ([adjusted cOR for TVS 6-11: 0.16 (95%

Journal of Neurology, 2021

Patients with anterior circulation ischemic strokes due to large vessel occlusion (AIS-LVO) and v... more Patients with anterior circulation ischemic strokes due to large vessel occlusion (AIS-LVO) and very severe neurological deficits (National Institutes of Health Stroke Scale (NIHSS) score > 25) were under-represented in clinical trials on endovascular treatment (EVT). We aimed to evaluate safety and outcomes of EVT in patients with very severe vs. severe (NIHSS score 15–25) neurological deficits. We included consecutive patients undergoing EVT for AIS-LVO between January 2015 and December 2019 at Lille University Hospital. We compared rates of parenchymal hemorrhage (PH), symptomatic intracranial hemorrhage (SICH), procedural complications, and 90-day mortality between patients with very severe vs. severe neurological deficit using univariable and multivariable logistic regression analyses. Functional outcome (90-days modified Rankin Scale) was compared between groups using ordinal logistic regression analysis. Among 1484 patients treated with EVT, 108 (7%) had pre-treatment NIHSS scores > 25, 873 (59%) with NIHSS scores 15–25 and 503 (34%) with NIHSS scores < 15. Rates of PH, SICH, successful recanalization, and procedural complications were similar in patients with NIHSS scores > 25 and NIHSS 15–25. Patients with NIHSS > 25 had a lower likelihood of improved functional outcome (adjcommon OR 0.31[95% CI 0.21–0.47]) and higher odds of mortality at 90 days (adjOR 2.3 [95% CI 1.5–3.7]) compared to patients with NIHSS 15–25. Successful recanalization was associated with better functional outcome (adjcommon OR 3.8 [95% CI 1.4–10.4]), and lower odds of mortality (adjOR 0.3 [95% CI 0.1–0.9]) in patients with very severe stroke. The therapeutic effect of recanalization on functional outcome and mortality was similar in both groups. In patients with very severe neurological deficit, EVT was safe and successful recanalization was strongly associated with better functional outcome at 90 days.

Late-breaking oral abstracts, 2021

Introduction The Contour device is a new intrasaccular flow disrupter designed to treat bifurcati... more Introduction The Contour device is a new intrasaccular flow disrupter designed to treat bifurcation and wide-neck bifurcation intracranial aneurysms. This device provides a stable scaffold framework across the aneurysm neck. The Contour is resheathable and re-deployable and the detachment method is electrolytic.We report our center's experience and mid-term

Journal of NeuroInterventional Surgery, 2020

BackgroundCoiling is the first-line treatment for the management of unruptured intracranial aneur... more BackgroundCoiling is the first-line treatment for the management of unruptured intracranial aneurysms (UIAs), but delayed thromboembolic events (TEEs) can occur after such treatment. ARETA (Analysis of Recanalization after Endovascular Treatment of Intracranial Aneurysm) is a prospective multicenter study conducted to analyze aneurysm recanalization. We analyzed delayed TEEs in the UIA subgroup.MethodsSixteen neurointerventional departments prospectively enrolled patients treated for ruptured and unruptured aneurysms between December 2013 and May 2015. Participant demographics, aneurysm characteristics, and endovascular techniques were recorded. Data were analyzed from participants with UIA treated by coiling or balloon-assisted coiling. We assessed the rates, timing, management, clinical outcomes, and risk factors for delayed TEEs using univariable and multivariable analyses.ResultsThe rate of delayed TEEs was 2.4% (95% CI 1.0% to 4.6%) in patients with unruptured aneurysms, with a...

18th International Conference on VLSI Design held jointly with 4th International Conference on Embedded Systems Design

Conventional RC oscillators, though offer inexpensive components as resistors and capacitors, are... more Conventional RC oscillators, though offer inexpensive components as resistors and capacitors, are not suitable for frequencies beyond few MHz. Here, a VCO based RC oscillator is proposed, where the output frequency can be programmed finely with digital codes over range of higher frequencies on the fly. In this architecture, divided output frequency of a VCO is compared precisely against an

Journal of NeuroInterventional Surgery, 2020

BackgroundCoiling, including balloon-assisted coiling (BAC), is the first-line therapy for ruptur... more BackgroundCoiling, including balloon-assisted coiling (BAC), is the first-line therapy for ruptured and unruptured aneurysms. Its efficacy can be clinically evaluated by bleeding/rebleeding rate after coiling, and anatomically evaluated by aneurysm occlusion post-procedure and during follow-up. We aimed to analyze immediate post-coiling aneurysm occlusion and associated factors within the Analysis of Recanalization after Endovascular Treatment of intracranial Aneurysm (ARETA) population.MethodsBetween December 2013 and May 2015, 16 neurointerventional departments prospectively enrolled participants treated for ruptured and unruptured aneurysms (ClinicalTrials.gov: NCT01942512). Participant demographics, aneurysm characteristics, and endovascular techniques were recorded. In patients with aneurysms treated by coiling or BAC, immediate post-operative aneurysm occlusion was independently evaluated by a core lab using a 3-grade scale: complete occlusion, neck remnant, and aneurysm remna...

Journal of NeuroInterventional Surgery, 2020

BackgroundEndovascular treatment is the first line therapy for the management of ruptured and unr... more BackgroundEndovascular treatment is the first line therapy for the management of ruptured and unruptured intracranial aneurysms, but delayed aneurysm rupture leading to bleeding/rebleeding can occur subsequently. ARETA (Analysis of Recanalization after Endovascular Treatment of intracranial Aneurysm) is a prospective, multicenter study conducted to analyze aneurysm recanalization. We analyzed delayed bleeding and rebleeding in this large cohort.Methods16 neurointerventional departments prospectively enrolled patients treated for ruptured and unruptured aneurysms between December 2013 and May 2015 (ClinicalTrials.gov: NCT01942512). Participant demographics, aneurysm characteristics and endovascular techniques were recorded. Data were analyzed from participants with ruptured or unruptured aneurysms treated by coiling or balloon-assisted coiling. Rates of bleeding and rebleeding were analyzed and associated factors were studied using univariable and multivariable analyses.ResultsThe bl...

Journal of Neuroradiology

Stroke

Background: Distal embolization (DE) is a common complication of endovascular treatment (EVT). We... more Background: Distal embolization (DE) is a common complication of endovascular treatment (EVT). We investigated the association of radiological thrombus characteristics and treatment details with DE. Methods: Patients with thin-slice (≤2.5 mm) baseline noncontrast computed tomography and computed tomography angiography from the ESCAPE-NA1 trial (Efficacy and Safety of Nerinetide for the Treatment of Acute Ischemic Stroke) were included. Thrombus annotation was performed manually on coregistered scans by experienced readers. We assessed thrombus location, distance from internal carotid artery terminus, length, perviousness, absolute attenuation, and hyperdense artery sign. In addition, we evaluated balloon guide catheter use during EVT, first-line EVT approach, the number of thrombectomy passes, and prior intravenous thrombolysis administration. DE was defined as the occurrence of emboli distal to the target artery or in new territories during EVT. The association between thrombus cha...

Computer Methods in Biomechanics and Biomedical Engineering: Imaging & Visualization

Stroke: Vascular and Interventional Neurology

Background First‐pass effect (FPE), that is, achieving reperfusion with a single thrombectomy dev... more Background First‐pass effect (FPE), that is, achieving reperfusion with a single thrombectomy device pass, is associated with better clinical outcomes in patients with acute stroke. FPE is therefore increasingly used as a marker of device and procedural efficacy. We aimed to evaluate the ability of thrombus‐based radiomics models to predict FPE in patients undergoing endovascular thrombectomy and compare performance with experts and nonradiomics thrombus characteristics. Methods Patients with thin‐slice noncontrast computed tomography and computed tomography angiography from the ESCAPE‐NA1 (Efficacy and Safety of Nerinetide for the Treatment of Acute Ischemic Stroke) trial were included. Thrombi were manually segmented on all images. Data were randomly split into a derivation set that included a training and a validation subset and an independent test set. Radiomics features were extracted from the derivation set. The machine learning models were compared with 3 expert stroke physic...

14th Congress of the European Society of Minimally Invasive Neurological Therapy 2022 Meeting Abstracts

Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques

Background: Trials of endovascular thrombectomy (EVT) for acute stroke have excluded patients wit... more Background: Trials of endovascular thrombectomy (EVT) for acute stroke have excluded patients with pre-morbid disability. We performed a meta-analysis to assess the effectiveness and safety of EVT in patients with pre-morbid disability. Methods: According to PRISMA guidelines, we searched for studies describing outcomes in patients with pre-morbid disability (modified Rankin Scale [mRS] 2-5), treated with EVT or medical management (MM). Random-effects meta-analysis was used to pool outcomes including return to baseline mRS at 90 days, symptomatic ICH (sICH), and 90-day mortality. Results: We analyzed 14 studies of patients with pre-morbid disability (mRS2-5: EVT=1,373, MM=253). Compared to medical therapy, EVT was associated with higher likelihood of return to baseline mRS (OR=2.37, 95%CI:1.39-4.04) and a trend towards lower mortality (OR=0.68, 95%CI:0.46-1.02), with similar odds of sICH (OR 1.01, 95%CI:0.49-2.08). In studies comparing patients with vs. without pre-morbid disability...

Stroke, 2022

Introduction: First-pass effect (FPE), i.e., achieving reperfusion with a single thrombectomy dev... more Introduction: First-pass effect (FPE), i.e., achieving reperfusion with a single thrombectomy device pass, is associated with better clinical outcomes in patients with acute stroke. FPE is therefore increasingly being used as a marker of device and procedural efficacy. We evaluated the ability of thrombus-based radiomics models to predict FPE in patients undergoing endovascular thrombectomy (EVT) and compare performance to experts and non-radiomics thrombus characteristics. Methods: Patients with thin-slice non-contrast CT and CT angiography from The Efficacy and Safety of Nerinetide for the Treatment of Acute Ischemic Stroke (ESCAPE-NA1) trial were included. Thrombi were manually segmented on all images. Data was randomly split into a derivation set that included a training and a validation subset and an independent test set. Radiomics features were extracted from the derivation data set. Three expert stroke physicians reviewed baseline imaging and clinical data for the test set. T...

Stroke, 2022

Background: Efficient healthcare workflow leads to faster reperfusion and better functional outco... more Background: Efficient healthcare workflow leads to faster reperfusion and better functional outcomes of stroke in the early-time window. We investigated the impact of care delays on the outcomes of stroke patients treated with endovascular thrombectomy (EVT) in the late window. Methods: Pooled data from seven randomized clinical trials and registries that only included patients who underwent EVT in the late time window (onset/last known well (LKW) time to imaging time of 6 hours or more) were combined for this analysis. The time intervals from stroke onset to successful reperfusion were analyzed. Logistic regression was used to estimate the likelihood of a functionally independent outcome at 90 days (modified Rankin scale 0-2) for each time interval while adjusting for relevant patients’ characteristics. Negative binomial regression was used to evaluate the relationship between each time interval and the predictors. Results: 584 patients were included in this analysis. The median ag...

Stroke, 2022

Background: 90-day home-time, the number of days a patient is back at their premorbid living situ... more Background: 90-day home-time, the number of days a patient is back at their premorbid living situation without an increase in level of care in the first 90 days post stroke, is routinely collected in administrative data. We evaluated the prediction of 90-day home-time using machine learning modelling in patients undergoing endovascular treatment (EVT). Methods: We used the QuICR provincial stroke registry and administrative data from Southern Alberta from Jan 2015-Dec 2019 to identify patients who underwent EVT. Imaging data were scored by 2-physician consensus. The primary outcome was 90 day home-time, which has a highly non-normal distribution with excess zero’s. We modelled using generalized boosting machine model with Gaussian distribution. Contribution of different covariates to hometime was determined using partial dependence plots. Results: We identified 659 EVT patients from Jan 2015 to Dec 2019 treated in Calgary, Alberta. Overall,median predicted 90d home-time was 41days (...

Stroke, 2022

Background: The outcome in stroke patients with ASPECTS of ≤5 who undergo Endovascular Thrombecto... more Background: The outcome in stroke patients with ASPECTS of ≤5 who undergo Endovascular Thrombectomy(EVT) in Large Vessel Occlusion (LVO) is uncertain. We used machine learning models to predict 90-day home-time in these patients. Methods: We used the QuICR provincial stroke registry and administrative data from Southern Alberta to identify patients who underwent EVT from Jan 2015-Dec 2019. Imaging data were scored by 2-physician consensus. The primary outcome was the predicted 90-day home-time(number of days a patient is back at their premorbid living situation without an increase in level of care within 90 days of the stroke) using generalized boosting machine model with Gaussian distribution. Covariate contribution to hometime was determined using partial dependence plots. Results: Of 659 EVT patients, 82(12%) had baseline ASPECTS ≤5(mean age 69.8y, 44.6% females, 93% good-moderate collaterals, M1 occlusion(64.1%). Overall, patients with low ASPECTS had lower median predicted home...

Stroke, 2022

Purpose: To validate the performance of a 3D convolutional neural network (CNN) based algorithm i... more Purpose: To validate the performance of a 3D convolutional neural network (CNN) based algorithm i.e. Stroke SENS LVO, in automatically detecting the presence of large vessel occlusions (LVO) on computed tomography angiography (CTA) images of the head. Method: A total of 400 studies (217 LVO, 183 non-LVO) were used in the analysis. The LVO group includes internal carotid artery (ICA) and m1 segment of the middle cerebral artery (M1-MCA) occlusions; and the non-LVO group includes more distal or posterior cerebral artery occlusions, no occlusions, and hemorrhagic stroke cases. Expert consensus reads were used as reference standard. Performance was evaluated using sensitivity and specificity and corresponding 95% confidence intervals (CI). Additional analysis was performed on several subgroups of interest. Results: For detecting LVO, the algorithm achieved a sensitivity of 0.894 [0.853, 0.935] and specificity of 0.874 [0.826, 0.922]. Furthermore, sensitivities of 0.857 [0.779, 0.935] on...

Stroke, 2022

Background and Purpose: Sex-related differences exist in many aspects of stroke and were mainly i... more Background and Purpose: Sex-related differences exist in many aspects of stroke and were mainly investigated in the early time window with conflicting results. However, data regarding sex disparities in late presenters are scarce. Therefore, we sought to investigate differences in outcomes between women and men treated with endovascular treatment (EVT) in the late time window. Methods: Analyses were based on the Selection Of Late-window Stroke for Thrombectomy by Imaging Collateral Extent Consortium, which was an individual-patient level analysis of seven trials and registries. Baseline characteristics, functional independence (modified Rankin Scale ≤ 2), mortality, and symptomatic intracranial hemorrhage (sICH) were compared between women and men. Effect of sex on the association between age, successful reperfusion (Thrombolysis in cerebral infarction 2b-3) and outcomes was assessed using multivariable logistic regression with interaction terms. Results: Among 608 patients treated ...

Stroke, 2022

Background and Purpose: Sex-related differences exist in many aspects of acute stroke and were ma... more Background and Purpose: Sex-related differences exist in many aspects of acute stroke and were mainly investigated in the early time window with conflicting results. However, data regarding sex disparities in late presenters are scarce. Therefore, we sought to investigate differences in outcomes between women and men treated with endovascular treatment in the late time window. Methods: Analyses were based on the SOLSTICE Consortium (Selection of Late-Window Stroke for Thrombectomy by Imaging Collateral Extent), which was an individual-patient level analysis of seven trials and registries. Baseline characteristics, 90-day functional independence (modified Rankin Scale score ≤2), mortality, and symptomatic intracranial hemorrhage were compared between women and men. Effect of sex on the association of age and successful reperfusion (final Thrombolysis in Cerebral Infarction 2b–3) with outcomes was assessed using multivariable logistic regression adjusted for age, National Institutes o...

Neuroradiology, 2021

Purpose Cortical vein opacification is not routinely assessed in patients presenting with acute i... more Purpose Cortical vein opacification is not routinely assessed in patients presenting with acute ischemic stroke (AIS), and the value of temporal assessment of venous outflow is not known. We evaluated the utility of assessing cortical venous drainage over time using multiphase CT angiography (mCTA). Methods Cortical venous drainage was assessed in patients from the Precise and Rapid Assessment of Collaterals Using Multi-Phase CTA in the Triage of Patients With Acute Ischemic Stroke for IA Therapy prospective multicenter cohort study of patients with symptoms of AIS with ICA and/or middle cerebral artery occlusion on baseline mCTA. Opacification of vein of Labbe, sphenoparietal sinus, superficial middle cerebral vein, and vein of Trolard of the affected hemisphere was graded as no (0), partial (1), or full (2) opacification in each mCTA phase. The venous opacification scores for each phase were added to generate a total venous score (TVS) (range 0-24). Primary outcome was 90-day modified Rankin score. Repeated measures analysis was used to assess the effect of phase timing on venous score on outcome. Results Of 432 patients, 284 (65.7%) had proximal arterial occlusions. Median venous opacification score per phase (range 0-8) was 3 (IQR 1-6) in the first phase and increased in the second and third phases [median (IQR): 6 (5-8) and 8 (6-8), respectively] of the mCTA. In a multivariable analysis adjusting for age, baseline National Institutes of Health Stroke Scale, and Alberta stroke program early CT score, a significant association between TVS and 90-day mRS was noted ([adjusted cOR for TVS 6-11: 0.16 (95%

Journal of Neurology, 2021

Patients with anterior circulation ischemic strokes due to large vessel occlusion (AIS-LVO) and v... more Patients with anterior circulation ischemic strokes due to large vessel occlusion (AIS-LVO) and very severe neurological deficits (National Institutes of Health Stroke Scale (NIHSS) score > 25) were under-represented in clinical trials on endovascular treatment (EVT). We aimed to evaluate safety and outcomes of EVT in patients with very severe vs. severe (NIHSS score 15–25) neurological deficits. We included consecutive patients undergoing EVT for AIS-LVO between January 2015 and December 2019 at Lille University Hospital. We compared rates of parenchymal hemorrhage (PH), symptomatic intracranial hemorrhage (SICH), procedural complications, and 90-day mortality between patients with very severe vs. severe neurological deficit using univariable and multivariable logistic regression analyses. Functional outcome (90-days modified Rankin Scale) was compared between groups using ordinal logistic regression analysis. Among 1484 patients treated with EVT, 108 (7%) had pre-treatment NIHSS scores > 25, 873 (59%) with NIHSS scores 15–25 and 503 (34%) with NIHSS scores < 15. Rates of PH, SICH, successful recanalization, and procedural complications were similar in patients with NIHSS scores > 25 and NIHSS 15–25. Patients with NIHSS > 25 had a lower likelihood of improved functional outcome (adjcommon OR 0.31[95% CI 0.21–0.47]) and higher odds of mortality at 90 days (adjOR 2.3 [95% CI 1.5–3.7]) compared to patients with NIHSS 15–25. Successful recanalization was associated with better functional outcome (adjcommon OR 3.8 [95% CI 1.4–10.4]), and lower odds of mortality (adjOR 0.3 [95% CI 0.1–0.9]) in patients with very severe stroke. The therapeutic effect of recanalization on functional outcome and mortality was similar in both groups. In patients with very severe neurological deficit, EVT was safe and successful recanalization was strongly associated with better functional outcome at 90 days.

Late-breaking oral abstracts, 2021

Introduction The Contour device is a new intrasaccular flow disrupter designed to treat bifurcati... more Introduction The Contour device is a new intrasaccular flow disrupter designed to treat bifurcation and wide-neck bifurcation intracranial aneurysms. This device provides a stable scaffold framework across the aneurysm neck. The Contour is resheathable and re-deployable and the detachment method is electrolytic.We report our center's experience and mid-term

Journal of NeuroInterventional Surgery, 2020

BackgroundCoiling is the first-line treatment for the management of unruptured intracranial aneur... more BackgroundCoiling is the first-line treatment for the management of unruptured intracranial aneurysms (UIAs), but delayed thromboembolic events (TEEs) can occur after such treatment. ARETA (Analysis of Recanalization after Endovascular Treatment of Intracranial Aneurysm) is a prospective multicenter study conducted to analyze aneurysm recanalization. We analyzed delayed TEEs in the UIA subgroup.MethodsSixteen neurointerventional departments prospectively enrolled patients treated for ruptured and unruptured aneurysms between December 2013 and May 2015. Participant demographics, aneurysm characteristics, and endovascular techniques were recorded. Data were analyzed from participants with UIA treated by coiling or balloon-assisted coiling. We assessed the rates, timing, management, clinical outcomes, and risk factors for delayed TEEs using univariable and multivariable analyses.ResultsThe rate of delayed TEEs was 2.4% (95% CI 1.0% to 4.6%) in patients with unruptured aneurysms, with a...

18th International Conference on VLSI Design held jointly with 4th International Conference on Embedded Systems Design

Conventional RC oscillators, though offer inexpensive components as resistors and capacitors, are... more Conventional RC oscillators, though offer inexpensive components as resistors and capacitors, are not suitable for frequencies beyond few MHz. Here, a VCO based RC oscillator is proposed, where the output frequency can be programmed finely with digital codes over range of higher frequencies on the fly. In this architecture, divided output frequency of a VCO is compared precisely against an

Journal of NeuroInterventional Surgery, 2020

BackgroundCoiling, including balloon-assisted coiling (BAC), is the first-line therapy for ruptur... more BackgroundCoiling, including balloon-assisted coiling (BAC), is the first-line therapy for ruptured and unruptured aneurysms. Its efficacy can be clinically evaluated by bleeding/rebleeding rate after coiling, and anatomically evaluated by aneurysm occlusion post-procedure and during follow-up. We aimed to analyze immediate post-coiling aneurysm occlusion and associated factors within the Analysis of Recanalization after Endovascular Treatment of intracranial Aneurysm (ARETA) population.MethodsBetween December 2013 and May 2015, 16 neurointerventional departments prospectively enrolled participants treated for ruptured and unruptured aneurysms (ClinicalTrials.gov: NCT01942512). Participant demographics, aneurysm characteristics, and endovascular techniques were recorded. In patients with aneurysms treated by coiling or BAC, immediate post-operative aneurysm occlusion was independently evaluated by a core lab using a 3-grade scale: complete occlusion, neck remnant, and aneurysm remna...

Journal of NeuroInterventional Surgery, 2020

BackgroundEndovascular treatment is the first line therapy for the management of ruptured and unr... more BackgroundEndovascular treatment is the first line therapy for the management of ruptured and unruptured intracranial aneurysms, but delayed aneurysm rupture leading to bleeding/rebleeding can occur subsequently. ARETA (Analysis of Recanalization after Endovascular Treatment of intracranial Aneurysm) is a prospective, multicenter study conducted to analyze aneurysm recanalization. We analyzed delayed bleeding and rebleeding in this large cohort.Methods16 neurointerventional departments prospectively enrolled patients treated for ruptured and unruptured aneurysms between December 2013 and May 2015 (ClinicalTrials.gov: NCT01942512). Participant demographics, aneurysm characteristics and endovascular techniques were recorded. Data were analyzed from participants with ruptured or unruptured aneurysms treated by coiling or balloon-assisted coiling. Rates of bleeding and rebleeding were analyzed and associated factors were studied using univariable and multivariable analyses.ResultsThe bl...