Nicolas Raposo

Nicolas Raposo
Centre Hospitalier Universitaire de Toulouse | CHU Toulouse · Service de Neurologie Vasculaire

MD PhD

About

96
Publications
10,823
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
1,248
Citations
Additional affiliations
November 2011 - present
Paul Sabatier University - Toulouse III
Position
  • Medical Doctor
November 2011 - present
Paul Sabatier University - Toulouse III
Position
  • Medical Doctor
November 2011 - present
Centre Hospitalier Universitaire de Toulouse
Position
  • Medical Doctor

Publications

Publications (96)
Article
Background Cerebral amyloid angiopathy (CAA) is an age-related small vessel disease, characterised pathologically by progressive deposition of amyloid β in the cerebrovascular wall. The Boston criteria are used worldwide for the in-vivo diagnosis of CAA but have not been updated since 2010, before the emergence of additional MRI markers. We report...
Article
Full-text available
Objective Cerebral amyloid angiopathy-related inflammation (CAA-ri) is a rare manifestation related to CAA, thought to be more severe. We aimed to compare the clinical and radiological outcomes of CAA-ri and non-inflammatory CAA. Materials and methods We retrospectively included all patients with CAA-ri from 13 French centers. We constituted a sex...
Article
Full-text available
Objective: Cerebral venous thrombosis caused by vaccine-induced immune thrombotic thrombocytopenia (VITT-CVT) is a rare adverse effect of adenovirus-based SARS-CoV-2 vaccines. In March 2021, after autoimmune pathogenesis of VITT was discovered, treatment recommendations were developed. These comprised immunomodulation, non-heparin anticoagulants,...
Article
Purpose: To determine whether reversal of DWI lesions (DWIr) on the DWI-ASPECTS (diffusion weighted imaging Alberta Stroke Program CT Score) template should serve as a predictor of 90-day clinical outcome in acute ischemic stroke (AIS) patients with pretreatment diffusion-weighted imaging (DWI)-ASPECTS 0-5 treated with thrombectomy, and to determi...
Article
Background and aims: Cerebral small vessel disease (CSVD) is the main cause of intracerebral Hemorrhage (ICH) in older individuals but has not been systematically studied in younger people. We aimed to evaluate the prevalence and characteristics of CSVD in young adults with symptomatic ICH. Methods: We conducted a cohort study of consecutive adults...
Article
Objective To evaluate the frequency, distribution, and clinical associations of the dilated appearance of cerebral cortical veins, termed cortical veins sign on T2*-weighted gradient recalled-echo (T2*-GRE) in the acute setting of migraine with aura attack in adult patients. Methods We conducted a retrospective analysis of 60 consecutive patients...
Article
Background Patients with pre-stroke disability, defined as a modified Rankin Scale (mRS) ≥3, were excluded from most trials of endovascular thrombectomy (EVT) for acute stroke. We sought to evaluate the prognostic factors associated with favorable outcome in stroke patients with known disability undergoing EVT, and the impact of successful reperfus...
Article
Full-text available
Background High systolic blood pressure (SBP) after aneurysmal subarachnoid hemorrhage (aSAH) has been associated with an increased risk of rebleeding. It remains unclear if an SBP lowering strategy before aneurysm treatment decreases this risk without increasing the risk of a delayed cerebral ischemia (DCI). Therefore, we compared the rates of in-...
Article
Importance Transient focal neurological episodes (TFNEs) are a frequently overlooked presentation of cerebral amyloid angiopathy (CAA), a condition with prognostic implications that are still not well described. Objective To perform a systematic review and meta-analysis to examine the factors associated with incident lobar intracerebral hemorrhage...
Article
Background Half of the patients with large vessel occlusion (LVO)-related acute ischemic stroke (AIS) who undergo endovascular reperfusion are dead or dependent at 3 months. We hypothesize that in addition to established prognostic factors, baseline imaging profile predicts outcome among reperfusers. Methods Consecutive patients receiving endovasc...
Article
Background and Purpose Procedural complications in thrombectomy for large vessel occlusions of the anterior circulation are not well described. We investigated the incidence, risk factors, and clinical implications of thrombectomy complications in daily clinical practice. Methods We used data from the ongoing prospective multicenter observational...
Article
Background and Purpose Determining the mechanism of large vessel occlusion related acute ischemic stroke is of major importance to initiate a tailored secondary prevention strategy. We investigated using the atherosclerosis, small vessel disease, cardiac source, other cause, dissection (ASCOD) classification the distribution of the causes of large...
Article
Full-text available
Importance: Thrombosis with thrombocytopenia syndrome (TTS) has been reported after vaccination with the SARS-CoV-2 vaccines ChAdOx1 nCov-19 (Oxford-AstraZeneca) and Ad26.COV2.S (Janssen/Johnson & Johnson). Objective: To describe the clinical characteristics and outcome of patients with cerebral venous sinus thrombosis (CVST) after SARS-CoV-2 vacc...
Article
Background and Purpose The influence of prior antiplatelet therapy (APT) uses on the outcomes of patients with acute ischemic stroke treated with endovascular therapy is unclear. We compared procedural and clinical outcomes of endovascular therapy in patients on APT or not before stroke onset. Methods We analyzed 2 groups from the ongoing prospect...
Article
Full-text available
Importance Prior trials of dual antiplatelet therapy excluded patients with moderate ischemic stroke. These patients were included in the Acute Stroke or Transient Ischaemic Attack Treated With Ticagrelor and ASA for Prevention of Stroke and Death (THALES) trial, but results have not been reported separately, raising concerns about safety and effic...
Article
Background and Purpose We aimed to evaluate among trained interventional neuroradiologist, whether increasing individual experience was associated with an improvement in mechanical thrombectomy (MT) procedural performance metrics. Methods Individual MT procedural data from 5 centers of the Endovascular Treatment in Ischemic Stroke registry and 2 a...
Article
Objective Mechanical thrombectomy (MT) is not recommended for acute stroke with large vessel occlusion (LVO) and a large volume of irreversibly injured tissue (“core”). Perfusion imaging may identify a subset of patients with large core who benefit from MT. Methods We compared two cohorts of LVO-related patients with large core (>50 ml on diffusio...
Article
Background and purpose: Whole-brain network connectivity has been shown to be a useful biomarker of cerebral amyloid angiopathy and related cognitive impairment. We evaluated an automated DTI-based method, peak width of skeletonized mean diffusivity, in cerebral amyloid angiopathy, together with its association with conventional MRI markers and co...
Article
Introduction: Peak width of skeletonized mean diffusivity (PSMD) is a novel fully automated diffusion tensor imaging (DTI) marker that has been consistently associated with cognition in cerebral small vessel disease (SVD) cohorts, including cerebral amyloid angiopathy (CAA). We hypothesized that PSMD would be more strongly associated with cognitive...
Article
Objective: Relying on tau-PET imaging, this cross-sectional study explored whether memory impairment is linked to the presence of concomitant tau pathology in subjects with Cerebral Amyloid Angiopathy (CAA). Methods: Forty-six subjects with probable CAA underwent a neuropsychological examination and an MRI for quantification of structural marker...
Article
This review paper summarises the yield of the different imaging modalities in the evaluation of patients for IV thrombolysis. Non-contrast CT and CTA or brain MRI combined with MRA are the recommended sequences for the evaluation of patients within the 4.5 hours time window. Multimodal MRI (DWI/PWI), and more recently, CT perfusion, offer reliable...
Article
Background and Purpose Mechanical thrombectomy (MT) is the recommended treatment for acute ischemic stroke caused by anterior circulation large vessel occlusion. However, despite a high rate of reperfusion, the clinical response to successful MT remains highly variable in the early time window where optimal imaging selection criteria have not been...
Article
Cerebral Amyloid Angiopathy (CAA) shows a high comorbidity with Alzheimer’s Disease (AD). Nonetheless, CAA is an independent neuropathological disorder, and over half of CAA cases present without AD‐related tau pathology. Differentiating CAA patients with or without concomitant tau pathology could have important implications for therapeutic approac...
Article
Résumé L’Angiopathie Amyloïde Cérébrale sporadique (AAC) est une micro angiopathie cérébrale fréquente, liée à l’âge, caractérisée par l’accumulation de peptide amyloïde Aβ dans la paroi des artères lepto-méningées et des vaisseaux corticaux. C’est la cause principale d’hémorragies intracérébrales lobaires de la personne âgée. Son origine reste lar...
Article
Full-text available
Background One quarter to one third of patients eligible for systemic thrombolysis are on antiplatelet therapy at presentation. In this study, we aimed to assess the safety and efficacy of intravenous thrombolysis in stroke patients on prescribed antiplatelet therapy in the WAKE-UP trial. Methods WAKE-UP was a multicenter, randomized, double-blind...
Article
Background Patients who have had a stroke with unknown time of onset have been previously excluded from thrombolysis. We aimed to establish whether intravenous alteplase is safe and effective in such patients when salvageable tissue has been identified with imaging biomarkers. Methods We did a systematic review and meta-analysis of individual pati...
Article
Full-text available
Objective To investigate whether acute convexity subarachnoid hemorrhage (cSAH) detected on CT in lobar intracerebral hemorrhage (ICH) related to cerebral amyloid angiopathy (CAA) is associated with recurrent ICH. Methods We analyzed data from a prospective cohort of consecutive acute lobar ICH survivors fulfilling the Boston criteria for possible...
Article
Background and purpose: The efficiency of prehospital care chain response and the adequacy of hospital resources are challenged amid the coronavirus disease 2019 (COVID-19) outbreak, with suspected consequences for patients with ischemic stroke eligible for mechanical thrombectomy (MT). Methods: We conducted a prospective national-level data col...
Article
Background Intracerebral hemorrhage (ICH) is a devastating presentation of Cerebral Amyloid Angiopathy (CAA), but mechanisms leading from vascular amyloid deposition to ICH are not well known. We investigated whether amyloid burden and MRI markers of small vessel disease (SVD) are increased in the ICH‐affected hemisphere compared to ICH‐free hemisp...
Article
Objective: To investigate whether acute convexity subarachnoid hemorrhage (cSAH) associated with acute lobar intracerebral hemorrhage (ICH) increases the risk of ICH recurrence in patients with cerebral amyloid angiopathy (CAA). Methods: We analyzed data from a prospective cohort of consecutive survivors of acute spontaneous lobar ICH fulfilling...
Article
Introduction: Target mismatch (TMM) identifies salvageable penumbra independent of time from stroke onset. Current guidelines do not recommend advanced imaging to select patients for mechanical thrombectomy (MT) within 6 hours after onset but indicate that more research is needed. To address this question, we designed a prospective multicenter coho...
Article
Full-text available
Background: Sporadic cerebral amyloid angiopathy shows progressive amyloid-β deposition in the wall of small arterioles and capillaries of the leptomeninges and cerebral cortex. Objective: To investigate whether amyloid load and distribution, assessed by florbetapir positron emission tomography, differs between patients with probable CAA-related...
Article
Background and Purpose— Relative signal intensity of acute ischemic stroke lesions in fluid-attenuated inversion recovery (fluid-attenuated inversion recovery relative signal intensity [FLAIR-rSI]) magnetic resonance imaging is associated with time elapsed since stroke onset with higher intensities signifying longer time intervals. In the randomize...
Article
Full-text available
After cerebral ischemia, events like neural plasticity and tissue reorganization intervene in lesioned and non-lesioned areas of the brain. These processes are tightly related to functional improvement and successful rehabilitation in patients. Plastic remodeling in the brain is associated with limited spontaneous functional recovery in patients. I...
Article
Full-text available
Purpose Enlarged perivascular spaces in the centrum semiovale (CSO-EPVS) have been linked to cerebral amyloid angiopathy (CAA). To get insight into the underlying mechanisms of this association, we investigated the relationship between amyloid-β deposition assessed by 18F-florbetapir PET and CSO-EPVS in patients with acute intracerebral hemorrhage...
Article
Full-text available
Background and Purpose: Whether patients with both lobar and deep cerebral microbleeds (mixed CMB) have advanced cerebral amyloid angiopathy (CAA), hypertensive angiopathy (HA) or both is uncertain. To get insight into the underlying small vessel disease (SVD) associated with mixed CMB, we explored its association with cortical superficial siderosi...
Thesis
L'angiopathie amyloïde cérébrale (AAC) sporadique est une microangiopathie cérébrale, dont l'intérêt auprès des cliniciens et des chercheurs est grandissant. L'AAC est fréquente chez les sujets âgés et constitue une cause majeure et croissante d'hémorragie intracérébrale et de démence. Des avancées importantes ont été réalisées ces dernières années...
Article
Objective: To describe the clinico-radiological features and long-term prognosis in patients with cerebral amyloid angiopathy-related inflammation (CAA-ri). Methods: Twenty-eight CAA-ri patients were recruited retrospectively from 6 neurological centers. We recorded the clinico-radiological and biological data, at baseline and during follow-up....
Article
Rationale The Boston criteria are used worldwide for the in vivo diagnosis of cerebral amyloid angiopathy and are the basis for clinical decision-making and research in the field. Given substantial advances in cerebral amyloid angiopathy's clinical aspects and MRI biomarkers, we designed a multicenter study within the International cerebral amyloid...
Article
Background and Purpose— Convexity subarachnoid hemorrhage (cSAH) is an increasingly recognized presentation of cerebral amyloid angiopathy (CAA), usually revealed by transient symptoms, but data on its outcome are limited. We compared the risk of future intracerebral hemorrhage (ICH), cSAH, and death in patients with CAA after cSAH and after lobar...
Article
Background and Purpose— Identifying underlying cerebral amyloid angiopathy (CAA) in patients with intracerebral hemorrhage (ICH) has important clinical implication. Convexity subarachnoid hemorrhage (cSAH) and subdural hemorrhage (SDH) are computed tomography features of CAA-related ICH. We explored whether cSAH and SDH could be additional magnetic...
Article
Background and purpose Diffusion‐weighted imaging (DWI) commonly detects acute ischaemic lesions in patients with acute intracerebral hemorrhage (ICH), especially with cerebral amyloid angiopathy (CAA). We investigated the relationship between cortical superficial siderosis (cSS), a neuroimaging marker of CAA, and DWI lesions in patients with acute...
Article
Full-text available
Purpose of Review The interest in SSRIs after stroke has increased in the past few years, with better knowledge of post-stroke depression and with the demonstrated capacity of some SSRIs to act on the functional recovery of non-depressed subjects. Recent Findings Arguments for the action of SSRIs in favour of post-stroke neurological function reco...
Article
Full-text available
Background: The risk of recurrent brain infarction (BI) is high within the first hours after a transient ischemic attack (TIA). Emergent, specialized, and tailored patient management in a TIA program reduces the risk of recurrent BI after TIA by 80%. New antithrombotic strategies have been successfully tested within 12 h after TIA onset. We aim to...
Article
Background: Transient ischemic attacks and minor stroke are vascular emergencies associated with a high risk of brain infarction within the first hours after onset. When available those patients may be evaluated and managed in a TIA clinic. Several therapeutic strategies are currently tested within 12 hrs after TIA/minor stroke onset. We aim to inv...
Article
Full-text available
Background: Cerebral amyloid angiopathy (CAA) is a common aetiology of convexal subarachnoid haemorrhage (cSAH) but little is known about its specific characteristics in comparison with cSAH from other causes. In this study we compared patients with CAA vs. non-CAA-related cSAH. Methods: Retrospective review of baseline and follow-up data of con...
Article
Background: Acute convexity subarachnoid hemorrhage (cSAH) and cortical superficial siderosis (cSS) are neuroimaging markers of cerebral amyloid angiopathy (CAA) that may arise through similar mechanisms. We sought to compare the prevalence of cSS between patients with CAA presenting with acute cSAH versus lobar intracerebral hemorrhage (ICH), and...
Article
Cerebral amyloid angiopathy is diagnosed in stroke units after lobar intracerebral hemorrhage. CAA can also be diagnosed in memory clinics when patients are referred for cognitive impairment assessment, and may be a reason for admission to emergency or neurology departments because of rapidly progressive cognitive or neurological decline, or a tran...
Data
Patterns of lesions for both intact and damaged subgroups. The normalized volumes of the lesions are expressed in mm3. The extent of the lesions within the main thalamic nucleus groups (medial, lateral, anterior, posterior), subgroups (mediodorsal, intralaminar, midline) and individual nuclei (magnocellular MD, MDpc) is expressed as a percentage of...
Data
Raw data (recognition tasks and neuropsychological assessment) for all the patients and healthy controls.
Article
Intracerebral hemorrhage (ICH) accounts for 15% of all strokes and approximately 50% of stroke-related mortality and disability worldwide. Patients who have experienced ICH are at high risk of negative outcome, including stroke and cognitive disorders. Vascular cognitive impairment are frequently seen after brain hemorrhage, yet little is known abo...
Article
OBJECTIVE: To assess whether 18F-florbetapir, a PET amyloid tracer, could bind vascular amyloid in cerebral amyloid angiopathy (CAA) by comparing cortical florbetapir retention during the acute phase between patients with CAA-related lobar intracerebral hemorrhage (ICH) and patients with hypertension-related deep ICH. METHODS: Patients with acute...
Article
Full-text available
Models of recognition memory have postulated that the mammillo-thalamic tract (MTT) / anterior thalamic nucleus (AN) complex would be critical for recollection while the Mediodorsal nucleus (MD) of the thalamus would support familiarity and indirectly also be involved in recollection (Aggleton et al., 2011). 12 patients with left thalamic stroke un...
Article
Full-text available
Background: Patients with minor acute ischemic stroke or transient ischemic attack are at high risk for subsequent stroke, and more potent antiplatelet therapy in the acute setting is needed. However, the potential benefit of more intense antiplatelet therapy must be assessed in relation to the risk for major bleeding. The SOCRATES trial (Acute St...
Article
Full-text available
Background Cognitive impairment seems to be frequent in intracerebral hemorrhage (ICH) survivors, but remains widely understudied. In this study, we investigated the frequency and patterns of vascular cognitive disorders (VCDs) in patients with cerebral amyloid angiopathy (CAA)-related and deep ICH compared to patients with mild cognitive impairmen...
Article
Background: Cerebral amyloid angiopathy (CAA) is a major cause of spontaneous lobar intracerebral hemorrhage (ICH) in the elderly. CAA-related ICH survivors are at substantial risk for recurrent ICH, accounting for the significant morbidity of the disease. Identifying predictors of recurrence is therefore crucial. Recent data have implicated cortic...
Article
Full-text available
Background Reversible cerebral vasoconstriction syndrome (RCVS) is a rare cause of intracerebral hemorrhage (ICH) causing intracranial hypertension. Methods Case report. Results We report a case of RCVS-related ICH leading to refractory intracranial hypertension. A decompressive craniectomy was performed to control intracranial pressure. We discu...
Article
Background: Identification of patients at highest risk of early stroke after transient ischaemic attack has been improved with imaging based scores. We aimed to compare the validity and prognostic utility of imaging-based stroke risk scores in patients after transient ischaemic attack. Methods: We did a pooled analysis of published and unpublish...
Article
IV thrombolysis (IVT) with recombinant tissue plasminogen activator (rtPA) is currently an approved therapy for acute ischemic stroke within 4.5 hours after onset. However, IVT increases the risk of symptomatic intracerebral hemorrhage (sICH), which is associated with poor functional outcome and mortality.¹ The identified risk factors for IVT-relat...