Joseph Benzakoun

• MD PhD
• GHU Paris Psychiatry and Neurosciences

Introduction Post-hoc analysis of recent trials comparing bridging therapy to endovascular therapy (EVT) alone reported improved recanalization results with bridging therapy. It remains uncertain whether the positive effect of prior intravenous thrombolysis (IVT) is consistent across all mechanical thrombectomy first-line techniques (Aspiration, St...

Electroconvulsive therapy (ECT) induces hippocampal volume increases in depressed patients, potentially reflecting neuroplasticity. We hypothesized that Neurite Orientation Dispersion and Density Imaging (NODDI) could provide in vivo evidence of hippocampal neuroplasticity following ECT. This longitudinal study evaluated 43 depressed patients under...

Purpose: In acute ischemic stroke, the typically employed 620×10 ⁻⁶ mm ² /s ADC threshold to automatically delineate the core on diffusion-weighted imaging (DWI) was established by overlaying the manually defined core onto the baseline ADC (ADC 0 ) in recanalized patients following intravenous thrombolysis. However, recanalization was assessed 3-6h...

BACKGROUND In ischemic cerebral small vessel diseases (cSVD), recurrent ischemic stroke is rare (2%–3% per year). Because acute ischemia may not always lead to stroke in cSVD due to the small size of lesions, acute stroke may not reliably reflect ischemic activity or the risk of further clinical worsening, as both incident lacunes and incidental di...

Due to their unique anatomy, paranasal sinuses have been used for comparative identification between post-mortem CT (PMCT) and ante-mortem CT (AMCT). However, data security issues arise when transferring raw AMCT images of a suspected identity. The aim of this study was to derive and validate an identification score based on CT slices extracted fro...

Post-mortem computed tomography (PMCT) is an increasingly utilized tool in forensic medicine for evaluating head gunshot injuries. Vault bevelling sign, when present, provides information regarding entry and exit wounds; when absent, identifying wound type on PMCT remains challenging. A cutaneous hyperdense ring, described in an animal study by Jun...

Purpose To evaluate performance of synthetic and real FLAIR for identifying early stroke in a multicenter cohort. Methods This retrospective study was conducted using DWI and FLAIR extracted from the Endovascular Treatment in Ischemic Stroke image registry (2017–2021). The database was partitioned into subsets according to MRI field strength and m...

Background and objectives Contrast enhancement in glioblastoma, IDH-wildtype is common but not systematic. In the era of the WHO 2021 Classification of CNS Tumors, the prognostic impact of a contrast enhancement and the pattern of contrast enhancement is not clearly elucidated. Methods We performed an observational, retrospective, single-centre co...

Purpose Frailty increases the risk of mortality among patients. We studied the prognostic significance of frailty using the modified 5-item frailty index (5-mFI) in patients harboring a newly diagnosed supratentorial glioblastoma, IDH-wildtype. Methods We retrospectively reviewed records of patients surgical treated at a single neurosurgical insti...

Background and Objectives Glioblastoma, IDH-wildtype presents with a typical ring-like contrast enhanced area surrounding a central necrosis on imaging. We assessed the prognosis of contrast enhancement. Methods We performed an observational, retrospective, single-centre cohort study at a tertiary neurosurgical oncology centre (January 2006 - Dece...

Introduction Electroconvulsive therapy (ECT) induces an increase in hippocampal volume presumed to reflect neurogenesis in severely depressed patients. We hypothesized that Neurite Orientation Dispersion and Density Imaging (NODDI) provides in vivo evidence of hippocampal neurogenesis following ECT. Methods This prospective longitudinal study incl...

Background and purpose In patients with acute ischemic stroke (AIS) treated with endovascular therapy (EVT), the association of pre-existing cerebral small vessel disease (cSVD) with symptomatic intracerebral hemorrhage (sICH) remains controversial. We tested the hypothesis that the presence of cerebral microbleeds (CMBs) and their burden would be...

OBJECTIVE The 2021 WHO classification of CNS tumors has refined the definition of adult-type diffuse gliomas without 1p19q codeletion. Nevertheless, the aggressiveness of gliomas is based exclusively on histomolecular criteria performed on a limited sample of the tumor. The authors aimed to assess whether the spontaneous radiographic tumor growth r...

BACKGROUND AND OBJECTIVES Cerebral venous sinus thrombosis (CVST) after supratentorial craniotomy is a poorly studied complication, for which there are no management guidelines. This study assessed the incidence, associated risk factors, and management of postoperative CVST after awake craniotomy. METHODS This is an observational, retrospective, m...

Introduction Reversible cerebral vasoconstriction syndrome (RCVS) is characterized by thunderclap headache and reversible cerebral arteries vasoconstriction. The pathophysiology remains unclear, but many triggers were reported. Case reports We reported two cases of patients with meningitis who developed RCVS confirmed by brain imaging. They presen...

The fifth edition of the World Health Organization (WHO) Classification of Tumors of the Central Nervous System has identified many new tumor types and has established, for the first time, essential and desirable diagnostic criteria for each of them. Among these, genetic alterations play an important role associated with morphology. For the first t...

Background: Diffusion-weighted imaging lesion reversal (DWIR) is frequently observed after mechanical thrombectomy for acute ischemic stroke, but little is known about age-related differences and impact on outcome. We aimed to compare, in patients <80 versus ≥80 years old, (1) the effect of successful recanalization on DWIR and (2) the impact of D...

Aims: Late auditory evoked potentials, and notably mismatch negativity (MMN) and P3 responses, can be used as part of the multimodal prognostic evaluation in post-anoxic disorders of consciousness (DOC). MMN response preferentially stems from the temporal cortex and the arcuate fasciculus. Situations with discrepant evaluations, for example MMN ab...

BACKGROUND: Remote diffusion-weighted imaging lesions (RDWILs) in the context of spontaneous intracerebral hemorrhage (ICH) are associated with an increased risk of recurrent stroke, worse functional outcome, and death. To update current knowledge on RDWILs, we conducted a systematic review and meta-analysis of the prevalence, associated factors an...

The Central Nervous System (CNS) tumor with BCOR internal tandem duplication (ITD) has recently been added as a novel embryonal histomolecular tumor type to the 2021 World Health Organization (WHO) Classification of CNS Tumors. In addition, other CNS tumors harboring a BCOR/BCORL1 fusion, which are defined by a distinct DNA-methylation profile, hav...

Background and purpose: Cerebral hypoperfusion has been reported in patients with COVID-19 and neurological manifestations in small cohorts. We aimed to systematically assess changes in cerebral perfusion in a cohort of 59 of these patients, with or without abnormalities on morphological MRI sequences. Methods: Patients with biologically-confirm...

Importance International guidelines recommend avoiding intravenous thrombolysis (IVT) in patients with ischemic stroke who have a recent intake of a direct oral anticoagulant (DOAC). Objective To determine the risk of symptomatic intracranial hemorrhage (sICH) associated with use of IVT in patients with recent DOAC ingestion. Design, Setting, and...

Background and purpose: FLAIR vascular hyperintensities are thought to represent leptomeningeal collaterals in acute ischemic stroke. However, whether all-FLAIR vascular hyperintensities or FLAIR vascular hyperintensities-DWI mismatch, ie, FLAIR vascular hyperintensities beyond the DWI lesion, best reflects collaterals remains debated. We aimed to...

Résumé Une femme de 46 ans souffrant d’une cardiopathie congénitale avec un syndrome d’Eisenmenger est décédée soudainement durant des exercices de relaxation. L’examen externe n’a pas permis d’identifier la cause de décès. Un scanner post-mortem du corps entier a été réalisé et a montré une lésion médiastino-hilaire hémorragique associé à un hémot...

Lobar hematomas represent around half of all supratentorial hemorrhages and have high mortality and morbidity. Their management depends on the underlying cause. Apart from local causes such as vascular malformation, which are rare and can usually be easily excluded thanks to imaging, the vast majority of lobar hematomas equally frequently result fr...

A novel histomolecular tumor, the “intracranial mesenchymal tumor (IMT), FET::CREB fusion-positive”, has recently been identified and added to the 2021 World Health Organization Classification of Tumors of the Central Nervous System. One of the essential diagnostic criteria defined in this classification is the intracranial location of the tumor. H...

PurposeTo report the results of systematic meningioma screening program implemented by French authorities in patients exposed to progestin therapies (cyproterone (CPA), nomegestrol (NA), and chlormadinone (CMA) acetate).Methods We conducted a prospective monocentric study on patients who, between September 2018 and April 2021, underwent standardize...

Background and purpose To determine the influence of the cerebral small vessel disease (SVD) burden on collateral recruitment in patients treated with mechanical thrombectomy (MT) for anterior circulation acute ischemic stroke (AIS). Methods Patients with AIS due to large vessel occlusion (LVO) from the Thrombectomie des Artères Cérébrales (THRACE...

Purpose: To report the results of systematic meningioma screening program implemented by French authorities in patients exposed to progestin therapies (cyproterone (CPA), nomegestrol (NA), and chlormadinone (CMA) acetate). Methods: We conducted a prospective monocentric study on patients who, between September 2018 and April 2021, underwent standar...

Background: Determine if early venous filling (EVF) after complete successful recanalization with mechanical thrombectomy in acute ischemic stroke is an independent predictor of symptomatic intracranial hemorrhage (sICH) and integrate EVF into a risk score for sICH prediction. Methods: Consecutive patients with anterior acute ischemic stroke tre...

Age estimation is a key factor for identification procedure in forensic context. Based on anthropological findings, degenerative changes of the sternal extremity of the 4th rib are currently used for age estimation. These have been adapted to post-mortem computed tomography (PMCT). The aim of this study was to validate a post-mortem computed tomogr...

Background Diagnosing probable cerebral amyloid angiopathy (CAA) after lobar intra-cerebral hemorrhage (l-ICH) currently relies on the MR-based modified Boston criteria (mBC). However, MRI has limited availability and the mBC have moderate sensitivity, with isolated l-ICH being classified as “possible CAA”. A recent autopsy-based study reported pot...

Carmustine wafers can be implanted in the surgical bed of high-grade gliomas, which can induce surgical bed cyst formation, leading to clinically relevant mass effect. An observational retrospective monocentric study was conducted including 122 consecutive adult patients with a newly diagnosed supratentorial glioblastoma who underwent a surgical re...

Objectif Déterminer l'influence de la maladie des petites artères cérébrales (MPA) sur le recrutement des collatérales leptoméningées chez les patients traités par thrombectomie mécanique (TM) à la phase aigüe d'un AVC ischémique de la circulation antérieure. Méthodes Les patients avec occlusion des gros vaisseaux traités par TM dans l'essai clini...

Les macroprogestatifs (acétate de cyprotérone [CPA], acétate de chlormadinone [CMA], acétate de nomégestrol [NA]) sont associés à un risque accru de méningiome. L'objectif était de déterminer la cinétique de décroissance des méningiomes après traitement conservateur en fonction du type de macroprogestatif. Nous avons rétrospectivement analysé une c...

Introduction: Arterial Spin Labeling (ASL) is an MRI technique used to non-invasively assess cerebral blood flow in clinical practice. In migraine aura, previous studies have shown both cortical hypoperfusion and hyperperfusion patterns. Sequential perfusion changes with alternation of hypoperfusion and hyperperfusion has been scarcely reported, on...

Background In acute ischemic stroke (AIS), fluid-attenuated inversion recovery (FLAIR) is used for treatment decisions when onset time is unknown. Synthetic FLAIR could be generated with deep learning from information embedded in diffusion-weighted imaging (DWI) and could replace acquired FLAIR sequence (real FLAIR) and shorten MRI duration. Purpos...

Background : Cerebral aspergillosis (CA) is a life-threatening disease for which diagnosis and management remain challenging. Detailed analyses from large cohorts are lacking. Methods : We included 119 cases of proven (n=55) or probable (n=64) CA diagnosed between 2006 and 2018 at 20 French hospitals. Data were collected at baseline and during fol...

A novel histomolecular tumor of the central nervous system, the “intracranial mesenchymal tumor (IMT), FET-CREB fusion-positive” has recently been identified in the literature and will be added to the 2021 World Health Organization Classification of Tumors of the Central Nervous System. However, our latest study using DNA-methylation analyses has r...

Objective Individualized patient selection for mechanical thrombectomy (MT) in patients with acute ischemic stroke (AIS) and large ischemic core (LIC) at baseline is an unmet need. We tested the hypothesis, that assessing the functional relevance of both the infarcted and hypo-perfused brain tissue, would improve the selection framework of patients...

The benefits of mechanical thrombectomy (MT) for patients with acute ischemic stroke (AIS) and a large ischemic core (LIC) at presentation are uncertain. We aimed to obtain up-to-date aggregate estimates of the outcomes following MT in patients with volumetrically assessed LIC. We conducted a Preferred Reporting Items for Systematic reviews and Met...

FET:CREB fusions have been described in a variety of tumors from various phenotypes. Recently, these fusion transcripts were reported in intracranial tumors, variably named intracranial mesenchymal myxoid tumors or angiomatoid fibrous histiocytomas. Controversy remains concerning the terminology for these tumors. Here, we report 11 cases of central...

Machine Learning (ML) has been proposed for tissue fate prediction after acute ischemic stroke (AIS), with the aim to help treatment decision and patient management. We compared three different ML models to the clinical method based on diffusion-perfusion thresholding for the voxel-based prediction of final infarct, using a large MRI dataset obtain...

Objective To determine whether the association between increasing number of clot retrieval attempts (CRA) and unfavorable outcome is due to an increase in emboli to new territory (ENT) and greater infarct growth (IG) in successfully recanalized patients with acute ischemic stroke due to large vessel occlusion (AIS LVO). Methods Data were extracted...

PurposeCarmustine wafers can be implanted in the surgical bed of high-grade gliomas, which can induce surgical bed cyst formation, leading to clinically relevant mass effect.Methods An observational retrospective monocentric study was conducted including 122 consecutive adult patients with a newly diagnosed supratentorial glioblastoma who underwent...

Background and PURPOSE In acute stroke, preventing infarct growth until complete recanalization occurs is a promising approach as an adjunct to reperfusion therapies to reduce infarct size and improve outcome. In rodent models, cathodal transcranial direct current stimulation (C-tDCS) decreases peri-infarct depolarizations and reduces infarct volum...

PurposeThe improving knowledge of interactions between meningiomas and progestin refines the management of this specific condition. We assessed the changes over time of the management of progestin-associated meningiomas.Methods We retrospectively studied consecutive adult patients who had at least one meningioma in the context of progestin intake (...

COVID-19 may affect various organs. This paper reports 9 patients (1/9 [11%] woman and 8/9 [89%] men, mean age 56 ± 13 years) with globe MRI abnormalities obtained from a multicenter cohort of 129 patients presenting with severe COVID-19 from March 4th to May 1st, 2020. 9/129 (7%) patients had one or several FLAIR-WI hyperintense nodules of the pos...

Despite early thrombectomy, a sizeable fraction of acute stroke patients with large vessel occlusion have poor outcome. The no-reflow phenomenon, i.e. impaired microvascular reperfusion despite complete recanalization, may contribute to such "futile recanalizations". Although well reported in animal models, no-reflow is still poorly characterized i...

Purpose: Number of Clot Retrieval Attempts (CRA) to achieve complete reperfusion by mechanical thrombectomy impacts functional outcome in acute ischemic stroke (AIS). Complete reperfusion (expanded Treatment In Cerebral Infarction; eTICI=3) at First-Pass (FP), is associated with highest rates of favorable outcome compared to complete reperfusion b...

Objective To describe neuroimaging findings and to report the epidemiological and clinical characteristics of COVID-19 patients with neurological manifestations. Methods In this retrospective multicenter study (10 Hospitals), we included 64 confirmed COVID-19 patients with neurologic manifestations who underwent a brain MRI. Results The cohort in...

Background Brain MRI parenchymal signal abnormalities have been in association with SARS-CoV-2. Purpose Describe the neuroimaging findings (excluding ischemic infarcts) in patients with severe COVID-19 infection. Methods This was a retrospective study of patients evaluated from March 23th, 2020 to April 27th, 2020 at 16 hospitals. Inclusion crite...

Acute stroke imaging. Imaging, within the first 24 hours of stroke, supports its clinical diagnosis and allows a careful patient selection for treatment. It excludes hemorrhage and stroke mimics, provides an estimate of potentially salvageable brain tissue, locates and characterizes the intra-arterial thrombus before treatment decision in acute isc...

Background and Purpose Patients with acute ischemic stroke, proximal vessel occlusion and a large ischemic core at presentation are commonly not considered for mechanical thrombectomy (MT). We tested the hypothesis that in patients with baseline large infarct cores, identification of remaining penumbral tissue using perfusion imaging would translat...

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...

Neuroimaging and especially MRI has emerged as a necessary imaging modality to detect, measure, characterize and monitor brain tumours. Advanced MRI sequences such as perfusion MRI, diffusion MRI and spectroscopy as well as new post-processing techniques such as automatic segmentation of tumours and radiomics play a crucial role in characterization...

Background: Long-term use of high-dose progestin is known to promote the development of meningioma. Atypical meningioma in a patient under progestin has not previously been reported. Case report: A 53-year-old right-handed woman presented with focal onset seizures, without impaired consciousness. Medical history featured endometriosis, treated succ...

Objectif La perfusion par marquage de spins artériel (ASL) est une technique d’IRM de perfusion non invasive prometteuse. Son application dans la vasculopathie cérébrale drépanocytaire reste néanmoins limité du fait de temps de transit artériel (TTA) allongés par le développement de nombreuses collatérales. L’ASL avec délais post-marquage multiples...

Objectif La vasculopathie cérébrale drépanocytaire se caractérise par une occlusion progressive des artères cérébrales et le développement de collatérales pour maintenir le débit sanguin cérébral. Nous avons évalué la prévalence et la signification des hyperintensités vasculaires en 3D T1 écho de spin rapide (FSE) après injection de chélates de gad...

Purpose In patients with ICA stenosis, increased peak systolic velocity is a marker of stenosis at risk of ischemic stroke. 4DFlow MRI is a reproducible technique to evaluate velocities in ICA stenosis, although it seems to underestimate velocities as compared with Doppler ultrasonography. The purpose of our study was to confirm that velocities wer...

Introduction: To determine the influence of white matter hyperintensity (WMH) burden on functional outcome, rate of symptomatic intracerebral hemorrhage (sICH), and procedural success in patients with acute ischemic stroke (AIS) treated by mechanical thrombectomy (MT) with current stentriever/aspiration devices. Methods: Patients with AIS due to...

Introduction L’aspergillose cérébrale (AC) est l’une des formes les plus sévères d’aspergillose invasive. L’objectif de ce travail est de décrire les caractéristiques cliniques, mycologiques, radiologiques, la prise en charge et le pronostic de ces patients. Matériels et méthodes Nous avons mené une étude rétrospective nationale multicentrique ent...

Introduction: The aim of this study was to assess the agreement between postmortem computed tomography (PMCT) and autopsy in detecting traumatic head injuries. Materials and methods: Consecutive cases of death that underwent both unenhanced PMCT and conventional autopsy were collected from our institution database during a period of 3 years and...

Objectives We tested whether FLAIR vascular hyperintensities (FVH)–DWI mismatch could identify candidates for thrombectomy most likely to benefit from revascularization. Methods We retrospectively reviewed 100 patients with proximal MCA occlusion from 18 stroke centers randomized in the IV-thrombolysis plus mechanical thrombectomy arm of the THRAC...

Introduction Cerebral white matter hyperintensity (WMH) on FLuid Attenuated Inversion Recovery (FLAIR) is linked to less favourable outcome in patients with acute ischemic stroke (AIS) but data on their relevance in patients with large vessel occlusion (LVO) treated with mechanical thrombectomy (MT) are sparse. In this post-hoc analysis of the MT a...

Background and Purpose— The acute management of stroke patients requires a fast and efficient screening imaging modality. We compared workflow and functional outcome in acute ischemic stroke patients screened by magnetic resonance imaging (MRI) or computed tomography (CT) before treatment in the THRACE trial (Thrombectomie des Artères Cérébrales),...

Purpose: Arterial spin labeling (ASL) is a non-invasive tool measuring cerebral blood flow (CBF) and is useful to assess acute neurological deficit. While acute stroke presents as hypoperfused vascular territory, epileptic activity causes cortical hyperperfusion. Other neurological conditions exhibit hyperperfusion, like migraine or secondary "lux...

Purpose To identify wall enhancement patterns on vessel wall MRI that discriminate between stable and unstable unruptured intracranial aneurysm (UIA). Materials and Methods Patients were included from November 2012 through January 2016. Vessel wall MR images were acquired at 3 T in patients with stable (incidental and nonchanging over 6 months) or...

Background and purpose: In acute ischemic stroke, whether FLAIR vascular hyperintensities represent good or poor collaterals remains controversial. We hypothesized that extensive FLAIR vascular hyperintensities correspond to good collaterals, as indirectly assessed by the hypoperfusion intensity ratio. Materials and methods: We included 244 cons...

Purpose To evaluate an objective computed tomographic (CT) criterion for distinguishing between part-solid (PS) and nonsolid (NS) lung nodules. Materials and Methods This study received institutional review board approval, and patients gave informed consent. Preoperative CT studies in all patients who underwent surgery for subsolid nodules between...

Background and purpose: Triage imaging facilitates the timely recognition of acute stroke with prognostic implications. Improvement in MR acquisition speed is needed given the extreme time constraints before treatment. We compared an ultrafast Echo-Planar FLAIR sequence (EPI-FLAIR) and a conventional FLAIR sequence (cFLAIR) for their diagnostic pe...

Background and aims: Post-procedural pain is frequent after transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC), and is only partially prevented by treatment selectivity. Our aim was to determine the risk factors of severe pain after selective TACE for HCC. Methods: From January 2012 to June 2014, all treatment-naïve patien...

Objectives: To evaluate the performance of a commercially available CAD system for automated detection and measurement of subsolid nodules. Materials and methods: The CAD system was tested on 50 pure ground-glass and 50 part-solid nodules (median diameter: 17mm) previously found on standard-dose CT scans in 100 different patients. True nodule de...

Little is known about the effectiveness of dose reduction options according to breast thickness. The purpose of this phantom study was to compare the effects on dose and noise of bismuth shielding versus a low kilovoltage for different breast thicknesses. CT acquisitions were performed first at 120 kVp (reference acquisition), then at 120 kVp with...

Introduction: Several treatments are proposed for castration-resistant prostate cancer (CRPC) at the metastatic stage. Monitoring of response using serum prostate-specific antigen (PSA) levels (sPSA) can be insufficient at this stage. Imaging has been proposed, in particular, nuclear medicine functional imaging and MRI, since response of predomina...