Lorena Nico - Academia.edu (original) (raw)

Papers by Lorena Nico

Research paper thumbnail of Comparing N-hexyl cyanoacrylate (Magic Glue) and N-butyl cyanoacrylate (NBCA) for neurovascular embolization using the pressure cooker technique: An experimental study in swine

Journal of Neuroradiology, Nov 1, 2021

BACKGROUND The pressure cooker (PC) technique uses a second microcatheter to produce a proximal o... more BACKGROUND The pressure cooker (PC) technique uses a second microcatheter to produce a proximal occlusion to prevent the reflux of liquid embolic agent (LEA) injected through a more distal microcatheter, and can be used to treat arteriovenous malformations and dural arteriovenous fistulae. The liquid embolic Magic Glue (MG) (N-hexyl cyanoacrylate (NHCA)) has been introduced as an alternative to N-butyl cyanoacrylate (NBCA). Our goals were to compare the extent of embolization of rete mirabile with or without the PC technique using NBCA or MG, and to compare the proximal occlusions obtained with MG or NBCA while using the PC technique in a renal arterial model. METHODS Rete mirabile were embolized with (n = 4) and without (n = 4) the PC technique, using MG (n = 4) or NBCA (n = 4). A renal arterial model was then used to study the characteristics of the MG plug (n = 10) used for the PC technique, and resistance to catheter withdrawal as compared to NBCA (n = 4). Specimens were analyzed macro- and microscopically and compared to angiographic results. RESULTS Extent of rete embolization with CYA agents was not significantly greater when using the PC technique. Results were similar with both types of cyanoacrylate (p = 0.657). The force necessary to withdraw the microcatheter was less with MG than with NBCA (p = 0.035). CONCLUSION MG was similar to NBCA in extent of rete embolization. Less traction force was necessary to withdraw trapped non-detachable microcatheters using MG compared to NBCA.

Research paper thumbnail of Thyroid node assessment: how can we avoid unnecessary surgical procedures?

Expert Review of Endocrinology & Metabolism, Nov 1, 2012

Fine needle aspiration cytology (FNAC) is still considered the ‘gold standard’ method for the dia... more Fine needle aspiration cytology (FNAC) is still considered the ‘gold standard’ method for the diagnosis of thyroid cancer. In our experience, this favorable opinion of cytology has led many doctors in their clinical practice to rely almost exclusively on this method when deciding whether or not to refer a patient for surgery. As a consequence, many patients undergo surgery prompted by an ‘indeterminate’ cytological diagnosis, while others go untreated on the strength of negative cytological findings alone. The practical outcome of this behavior is that about 80% of the patients referred to the surgeon with an indeterminate cytology are found afterwards to be carrying a benign disease and their surgical procedure could have been avoided in most cases, whereas a recent review has demonstrated that cytology fails to identify a malignancy in up to 30% of patients for whom surgery would clearly be warranted [1].

Research paper thumbnail of Republished: Endovascular recanalization of the common carotid artery in a patient with radio induced chronic occlusion

Journal of NeuroInterventional Surgery, Nov 4, 2016

Recanalization of chronic occlusion of the common carotid artery (CCA) in patients with a history... more Recanalization of chronic occlusion of the common carotid artery (CCA) in patients with a history of neck irradiation is challenging, both for vascular surgeons and interventional neuroradiologists. We describe a case of successful stenting of radio induced chronic occlusion of the right CCA in a 41-year-old patient with neurological deterioration and minor stroke due to cerebral hypoperfusion caused by concomitant bilateral arterial occlusions. Direct surgery and surgical bypass were considered contraindicated. The endovascular approach was successful and required multiple precautions during the procedure. We describe particular solutions, not used in day to day practice, that allowed us to carry out the endovascular treatment in this unusual situation.

Research paper thumbnail of Successful Reperfusion is Associated with Favorable Functional Outcome despite Vessel Perforation during Thrombectomy: A Case Series and Systematic Review

American Journal of Neuroradiology, Sep 29, 2022

Research paper thumbnail of Comparison of the diagnostic accuracy of combined elastosonography and BRAF analysis vs cytology and ultrasonography for thyroid nodule suspected of malignancy

Clinical Endocrinology, Sep 11, 2012

Objective Diagnosing thyroid nodules preoperatively using traditional diagnostic toolsultrasonogr... more Objective Diagnosing thyroid nodules preoperatively using traditional diagnostic toolsultrasonography (US) and cytologystill carries a considerable degree of uncertainty, and surgery is recommended for a far from negligible number of patients simply for diagnostic purposes. Thyroid elastosonography (USE) and BRAF analysis have recently proved useful in detecting thyroid malignancies. The aim of this study is to establish whether combining USE and BRAF testing ameliorates preoperative diagnosis of thyroid nodule candidates for intervention by conventional approaches, thereby avoiding the need for diagnostic surgical procedures. Design and Patients We retrospectively analysed the files of 155 consecutive patients with 164 nodules, all assessed by ultrasonography, cytology, USE and BRAF testing, who underwent thyroid surgery. Results Of the 164 nodules, 74 (45%) were benign and 90 (55%) were malignant at final histology. Combining ultrasonography and cytology identified 21 (13%) as benign, 93 (57%) as malignant or probably malignant and 50 (30%) as 'suspended' (when the combined test was not able to classify the node as benign or malignant) with a 99% sensitivity, 28% specificity, 63% PPV, 95% NPV and 67% accuracy. Combining USE and BRAF testing indicated that 59 (36%) were benign, 74 (45%) were malignant and 31 (19%) were in a 'suspended' category, with a 95% sensitivity, 74% specificity, 82% PPV, 93% NPV and 86% accuracy. Conclusions In assessing thyroid nodules suspected of malignancy, the combined analysis of USE and BRAF is equally sensitive and more specific than conventional procedures, achieving more accurate preoperative diagnoses than US and cytology combined. USE and BRAF analysis for thyroid nodule evaluation might reduce the number of unnecessary surgical procedures.

Research paper thumbnail of Transvenous Approach for the Treatment of cerebral Arteriovenous Malformations (TATAM): Study protocol of a randomised controlled trial

Interventional Neuroradiology, Feb 4, 2019

BackgroundTransvenous embolisation is a promising technique but the benefits remain uncertain. We... more BackgroundTransvenous embolisation is a promising technique but the benefits remain uncertain. We hypothesised that transvenous embolisation leads to a higher rate of arteriovenous malformation angiographic occlusion than transarterial embolisation.MethodsThe Transvenous Approach for the Treatment of cerebral Arteriovenous Malformations (TATAM) is an investigator initiated, multicentre, prospective, phase 2, randomised controlled clinical trial. To test the hypothesis that transvenous embolisation is superior to transarterial embolisation for arteriovenous malformation obliteration, 76 patients with arteriovenous malformations considered curable by up to two sessions of endovascular therapy will be randomly allocated 1:1 to treatment with either transvenous embolisation (with or without transarterial embolisation) (experimental arm) or transarterial embolisation alone (control arm). The primary endpoint of the trial is complete arteriovenous malformation occlusion, assessed by catheter cerebral angiography. Complete occlusions will be confirmed at 3 months, while incompletely occluded arteriovenous malformations, considered treatment failures, will then be eligible for complementary treatments by surgery, radiation therapy, or even transvenous embolisation. Standard procedural safety outcomes will also be assessed. Patient selection will be validated by a case selection committee, and participating centres with limited experience in transvenous embolisation will be proctored.DiscussionThe TATAM trial is a transparent research framework designed to offer a promising but still unvalidated treatment to selected arteriovenous malformation patients.Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: {"type":"clinical-trial","attrs":{"text":"NCT03691870","term_id":"NCT03691870"}}NCT03691870.

Research paper thumbnail of A randomized pilot study of patients with tandem carotid lesions undergoing thrombectomy

Journal of Neuroradiology, Nov 1, 2020

Background and purpose.-The optimal management of patients with tandem lesions (TL), or cervical ... more Background and purpose.-The optimal management of patients with tandem lesions (TL), or cervical internal carotid artery (c-ICA) steno-occlusive pathology and ipsilateral intracranial occlusion, who are undergoing endovascular thrombectomy (EVT) remains unknown. We sought to establish the feasibility of a trial designed to address this question. Materials and methods.-The Endovascular Acute Stroke Intervention (EASI) study was a single-centre randomized trial comparing EVT to medical therapy for large-vessel occlusion stroke. Patients with TL receiving EVT were randomly allocated to acute c-ICA stenting or no stenting. The primary outcome was the proportion of patients with a modified Rankin Scale (mRS) score of 0-2 at 90 days. Safety outcomes were symptomatic intracranial hemorrhage (sICH) at 24 hours and mortality at 90 days. Results.-Of 301 patients included in EASI between 2013 and 2018, 24 (8.0%) with TL were randomly allocated to acute stenting (n = 13) or no stenting (n = 11). Baseline characteristics were balanced. Eight (61.5%; 95% CI 35.5%-82.3%) and 7 (63.6%; 95% CI 35.4%-84.9%) patients, respectively, had a favorable outcome (mRS 0-2; P = 1.0). One non-stented patient had a symptomatic intracerebral hemorrhage. Conclusions.-This pilot trial of patients with TL undergoing EVT suggests that a sufficiently powered larger TL trial comparing acute c-ICA stenting to no stenting is feasible. Clinical Trial Registration.-URL: http://www.clinicaltrials.gov. Unique identifier: NCT02157532.

Research paper thumbnail of Stent-Assisted Coiling in the Treatment of Unruptured Intracranial Aneurysms: A Randomized Clinical Trial

American Journal of Neuroradiology, Mar 16, 2023

BACKGROUND AND PURPOSE: Stent-assisted coiling may improve angiographic results of endovascular t... more BACKGROUND AND PURPOSE: Stent-assisted coiling may improve angiographic results of endovascular treatment of unruptured intracranial aneurysms compared with coiling alone, but this has never been shown in a randomized trial. MATERIALS AND METHODS: The Stenting in the Treatment of Aneurysm Trial was an investigator-led, parallel, randomized (1:1) trial conducted in 4 university hospitals. Patients with intracranial aneurysms at risk of recurrence, defined as large aneurysms ($10 mm), postcoiling recurrent aneurysms, or small aneurysms with a wide neck ($4 mm), were randomly allocated to stent-assisted coiling or coiling alone. The composite primary efficacy outcome was "treatment failure," defined as initial failure to treat the aneurysm; aneurysm rupture or retreatment during follow-up; death or dependency (mRS. 2); or an angiographic residual aneurysm adjudicated by an independent core laboratory at 12 months. The primary hypothesis (revised for slow accrual) was that stent-assisted coiling would decrease treatment failures from 33% to 15%, requiring 200 patients. Primary analyses were intent to treat. RESULTS: Of 205 patients recruited between 2011 and 2021, ninety-four were allocated to stent-assisted coiling and 111 to coiling alone. The primary outcome, ascertainable in 203 patients, was reached in 28/93 patients allocated to stent-assisted coiling (30.1%; 95% CI, 21.2%-40.6%) compared with 30/110 (27.3%; 95% CI, 19.4%-36.7%) allocated to coiling alone (relative risk ¼ 1.10; 95% CI, 0.7-1.7; P ¼ .66). Poor clinical outcomes (mRS .2) occurred in 8/94 patients allocated to stent-assisted coiling (8.5%; 95% CI, 4.0%-16.6%) compared with 6/111 (5.4%; 95% CI, 2.2%-11.9%) allocated to coiling alone (relative risk ¼ 1.6; 95% CI, 0.6%-4.4%; P ¼ .38).

Research paper thumbnail of Endovascular recanalization of the common carotid artery in a patient with radio induced chronic occlusion

Case Reports, Nov 1, 2016

Research paper thumbnail of Patient Selection in a Pragmatic Study on the Management of Patients with Brain Arteriovenous Malformations

Research paper thumbnail of Successful Reperfusion is Associated with Favorable Functional Outcome despite Vessel Perforation during Thrombectomy: A Case Series and Systematic Review

American Journal of Neuroradiology

Research paper thumbnail of Surgical treatment of brain arteriovenous malformations: clinical outcomes of patients included in the registry of a pragmatic randomized trial

Journal of Neurosurgery

OBJECTIVE The Treatment of Brain Arteriovenous Malformations Study (TOBAS) is a pragmatic study t... more OBJECTIVE The Treatment of Brain Arteriovenous Malformations Study (TOBAS) is a pragmatic study that includes 2 randomized trials and registries of treated or conservatively managed patients. The authors report the results of the surgical registry. METHODS TOBAS patients are managed according to an algorithm that combines clinical judgment and randomized allocation. For patients considered for curative treatment, clinicians selected from surgery, endovascular therapy, or radiation therapy as the primary curative method, and whether observation was a reasonable alternative. When surgery was selected and observation was deemed unreasonable, the patient was not included in the randomized controlled trial but placed in the surgical registry. The primary outcome of the trial was mRS score > 2 at 10 years (at last follow-up for the current report). Secondary outcomes include angiographic results, perioperative serious adverse events, and permanent treatment-related complications leadin...

Research paper thumbnail of Thrombectomy alone versus intravenous alteplase plus thrombectomy in patients with stroke: an open-label, blinded-outcome, randomised non-inferiority trial

Research paper thumbnail of Reliability of CT Angiography in Cerebral Vasospasm: A Systematic Review of the Literature and an Inter- and Intraobserver Study

American Journal of Neuroradiology, 2020

BACKGROUND AND PURPOSE: Computed tomography angiography offers a non-invasive alternative to DSA ... more BACKGROUND AND PURPOSE: Computed tomography angiography offers a non-invasive alternative to DSA for the assessment of cerebral vasospasm following subarachnoid hemorrhage but there is limited evidence regarding its reliability. Our aim was to perform a systematic review (Part I) and to assess (Part II) the inter-and intraobserver reliability of CTA in the diagnosis of cerebral vasospasm. MATERIALS AND METHODS: In Part I, articles reporting the reliability of CTA up to May 2018 were systematically searched and evaluated. In Part II, 11 raters independently graded 17 arterial segments in each of 50 patients with SAH for the presence of vasospasm using a 4-category scale. Raters were additionally asked to judge the presence of any moderate/severe vasospasm ($ 50% narrowing) and whether findings would justify augmentation of medical treatment or conventional angiography 6 balloon angioplasty. Four raters took part in the intraobserver reliability study. RESULTS: In Part I, the systematic review revealed few studies with heterogeneous vasospasm definitions. In Part II, we found interrater reliability to be moderate at best (k # 0.6), even when results were stratified according to specialty and experience. Intrarater reliability was substantial (k. 0.6) in 3/4 readers. In the per arterial segment analysis, substantial agreement was reached only for the middle cerebral arteries, and only when senior raters' judgments were dichotomized (presence or absence of $50% narrowing). Agreement on the medical or angiographic management of vasospasm based on CTA alone was less than substantial (k # 0.6). CONCLUSIONS: The diagnosis of vasospasm using CTA alone was not sufficiently repeatable among observers to support its general use to guide decisions in the clinical management of patients with SAH.

Research paper thumbnail of Pénétration de cyanoacrylates d’alpha-hexil et de n-butyle à l’aide de la technique modifiée de « pressure cooker technique » : une étude expérimentale chez l’animal

Journal of Neuroradiology, 2019

photonique) ont révélé que le greffage du peptide P8RI améliore la qualité de son endothélialisat... more photonique) ont révélé que le greffage du peptide P8RI améliore la qualité de son endothélialisation avec une meilleure intégration du dispositif à l'interface sang-vaisseaux. Aucune occlusion de branche artérielle couverte par le dispositif n'a été observée. Conclusion Ces résultats constituent une étape cruciale en vue d'un passage à l'Homme. Cette technique de recouvrement pourra être proposé également pour les autres dispositifs intra-artériels utilisés en neuroradiologie interventionnelle. Mots clés Flow-diverter ; Recourvrement/coating ; P8RI ; CD31. Déclaration de liens d'intérêts Les auteurs déclarent ne pas avoir de liens d'intéreˆts.

Research paper thumbnail of Stent-Assisted Coiling in the Treatment of Unruptured Intracranial Aneurysms: A Randomized Clinical Trial

American Journal of Neuroradiology

BACKGROUND AND PURPOSE: Stent-assisted coiling may improve angiographic results of endovascular t... more BACKGROUND AND PURPOSE: Stent-assisted coiling may improve angiographic results of endovascular treatment of unruptured intracranial aneurysms compared with coiling alone, but this has never been shown in a randomized trial. MATERIALS AND METHODS: The Stenting in the Treatment of Aneurysm Trial was an investigator-led, parallel, randomized (1:1) trial conducted in 4 university hospitals. Patients with intracranial aneurysms at risk of recurrence, defined as large aneurysms ($10 mm), postcoiling recurrent aneurysms, or small aneurysms with a wide neck ($4 mm), were randomly allocated to stent-assisted coiling or coiling alone. The composite primary efficacy outcome was "treatment failure," defined as initial failure to treat the aneurysm; aneurysm rupture or retreatment during follow-up; death or dependency (mRS. 2); or an angiographic residual aneurysm adjudicated by an independent core laboratory at 12 months. The primary hypothesis (revised for slow accrual) was that stent-assisted coiling would decrease treatment failures from 33% to 15%, requiring 200 patients. Primary analyses were intent to treat. RESULTS: Of 205 patients recruited between 2011 and 2021, ninety-four were allocated to stent-assisted coiling and 111 to coiling alone. The primary outcome, ascertainable in 203 patients, was reached in 28/93 patients allocated to stent-assisted coiling (30.1%; 95% CI, 21.2%-40.6%) compared with 30/110 (27.3%; 95% CI, 19.4%-36.7%) allocated to coiling alone (relative risk ¼ 1.10; 95% CI, 0.7-1.7; P ¼ .66). Poor clinical outcomes (mRS .2) occurred in 8/94 patients allocated to stent-assisted coiling (8.5%; 95% CI, 4.0%-16.6%) compared with 6/111 (5.4%; 95% CI, 2.2%-11.9%) allocated to coiling alone (relative risk ¼ 1.6; 95% CI, 0.6%-4.4%; P ¼ .38).

Research paper thumbnail of O-031 Is flow diversion the best treatment of cavernous carotid aneurysms?

Oral Abstracts, 2018

Background and Purpose Cavernous carotid aneurysms can cause pain and ophtalmoplegia from mass ef... more Background and Purpose Cavernous carotid aneurysms can cause pain and ophtalmoplegia from mass effect, but they rarely rupture or cause life threatening complications. Treatment options include observation, parent vessel occlusion, coil embolization, or in the last decade flow-diversion (FD). We aimed to compare the results of FD with more conventional treatments in patients with cavernous aneurysms recruited in the Flow Diverter in the Treatment of Aneurysms trial (FIAT). Materials and methods FIAT, conducted in 3 Canadian hospitals, proposed randomized allocation to flow diversion or standard management options (observation, coil embolization, parent vessel occlusion, or clip placement), and a registry of nonrandomized patients treated with flow diversion. The primary safety outcome was death or dependency (modified Rankin Scale score >2) at 3 months, to be determined for all patients who received flow diversion at any time. The primary efficacy outcome was angiographic occlusion at 3–12 months combined with an independent clinical outcome. Results Forty-two patients with cavernous aneurysms were included in the FIAT study. In 31 patients, treatment was randomly allocated: 17 were treated with FD, 14 using best standard treatment (BST). Eleven patients treated with FD were judged untreatable otherwise. An hemorrhagic complication occurred in 3/28 patients treated with FD (11%; 3.7%–27.2%), as compared to 0/14 with BST (0%–21.5%) Overall, we had a 3% mortality rate and a 7% major neurologic complication rate. Conclusion Flow diversion in CCAs was not safe as hypothesized. We observed unusual and potentially fatal hemorrhagic complications in patients treated with FD that need to be attentively analyzed, especially considered that CCAs hemorrhagic presentation is a rare event. More randomized trials are needed to determine the role of flow diversion in the management of cavernous carotid aneurysms. Disclosures L. Nico: 1; C; Medtronic-Covidien. A. Weill: None. D. Roy: None. J. Raymond: None.

Research paper thumbnail of Exophtalmie aiguë après thrombectomie mécanique pour occlusion intracrânienne: une étude rétrospective

Journal of Neuroradiology, 2019

Research paper thumbnail of Angiographic results of surgical or endovascular treatment of intracranial aneurysms: a systematic review and inter-observer reliability study

Neuroradiology

Results of surgical or endovascular treatment of intracranial aneurysms are often assessed using ... more Results of surgical or endovascular treatment of intracranial aneurysms are often assessed using angiography. A reliable method to report results irrespective of treatment modality is needed to enable comparisons. Our goals were to systematically review existing classification systems, and to propose a 3-point classification applicable to both treatments and assess its reliability. We conducted two systematic reviews on classification systems of angiographic results after clipping or coiling to select a simple 3-category scale that could apply to both treatments. We then circulated an electronic portfolio of angiograms of clipped (n=30) or coiled (n=30) aneurysms, and asked raters to evaluate the degree of occlusion using this scale. Raters were also asked to choose an appropriate follow-up management for each patient based on the degree of occlusion. Agreement was assessed using Krippendorff’s α statistics (αK), and relationship between occlusion grade and clinical management was analyzed using Fisher’s exact and Cramer’s V tests. The systematic reviews found 70 different grading scales with heterogeneous reliability (kappa values from 0.12 to 1.00). The 60-patient portfolio was independently evaluated by 19 raters of diverse backgrounds (neurosurgery, radiology, and neurology) and experience. There was substantial agreement (αK=0.76, 95%CI, 0.67–0.83) between raters, regardless of background, experience, or treatment used. Intra-rater agreement ranged from moderate to almost perfect. A strong relationship was found between angiographic grades and management decisions (Cramer’s V: 0.80±0.12). A simple 3-point scale demonstrated sufficient reliability to be used in reporting aneurysm treatments or in evaluating treatment results in comparative randomized trials.

Research paper thumbnail of Comparing N-hexyl cyanoacrylate (Magic Glue) and N-butyl cyanoacrylate (NBCA) for neurovascular embolization using the pressure cooker technique: An experimental study in swine

Journal of Neuroradiology

BACKGROUND The pressure cooker (PC) technique uses a second microcatheter to produce a proximal o... more BACKGROUND The pressure cooker (PC) technique uses a second microcatheter to produce a proximal occlusion to prevent the reflux of liquid embolic agent (LEA) injected through a more distal microcatheter, and can be used to treat arteriovenous malformations and dural arteriovenous fistulae. The liquid embolic Magic Glue (MG) (N-hexyl cyanoacrylate (NHCA)) has been introduced as an alternative to N-butyl cyanoacrylate (NBCA). Our goals were to compare the extent of embolization of rete mirabile with or without the PC technique using NBCA or MG, and to compare the proximal occlusions obtained with MG or NBCA while using the PC technique in a renal arterial model. METHODS Rete mirabile were embolized with (n = 4) and without (n = 4) the PC technique, using MG (n = 4) or NBCA (n = 4). A renal arterial model was then used to study the characteristics of the MG plug (n = 10) used for the PC technique, and resistance to catheter withdrawal as compared to NBCA (n = 4). Specimens were analyzed macro- and microscopically and compared to angiographic results. RESULTS Extent of rete embolization with CYA agents was not significantly greater when using the PC technique. Results were similar with both types of cyanoacrylate (p = 0.657). The force necessary to withdraw the microcatheter was less with MG than with NBCA (p = 0.035). CONCLUSION MG was similar to NBCA in extent of rete embolization. Less traction force was necessary to withdraw trapped non-detachable microcatheters using MG compared to NBCA.

Research paper thumbnail of Comparing N-hexyl cyanoacrylate (Magic Glue) and N-butyl cyanoacrylate (NBCA) for neurovascular embolization using the pressure cooker technique: An experimental study in swine

Journal of Neuroradiology, Nov 1, 2021

BACKGROUND The pressure cooker (PC) technique uses a second microcatheter to produce a proximal o... more BACKGROUND The pressure cooker (PC) technique uses a second microcatheter to produce a proximal occlusion to prevent the reflux of liquid embolic agent (LEA) injected through a more distal microcatheter, and can be used to treat arteriovenous malformations and dural arteriovenous fistulae. The liquid embolic Magic Glue (MG) (N-hexyl cyanoacrylate (NHCA)) has been introduced as an alternative to N-butyl cyanoacrylate (NBCA). Our goals were to compare the extent of embolization of rete mirabile with or without the PC technique using NBCA or MG, and to compare the proximal occlusions obtained with MG or NBCA while using the PC technique in a renal arterial model. METHODS Rete mirabile were embolized with (n = 4) and without (n = 4) the PC technique, using MG (n = 4) or NBCA (n = 4). A renal arterial model was then used to study the characteristics of the MG plug (n = 10) used for the PC technique, and resistance to catheter withdrawal as compared to NBCA (n = 4). Specimens were analyzed macro- and microscopically and compared to angiographic results. RESULTS Extent of rete embolization with CYA agents was not significantly greater when using the PC technique. Results were similar with both types of cyanoacrylate (p = 0.657). The force necessary to withdraw the microcatheter was less with MG than with NBCA (p = 0.035). CONCLUSION MG was similar to NBCA in extent of rete embolization. Less traction force was necessary to withdraw trapped non-detachable microcatheters using MG compared to NBCA.

Research paper thumbnail of Thyroid node assessment: how can we avoid unnecessary surgical procedures?

Expert Review of Endocrinology & Metabolism, Nov 1, 2012

Fine needle aspiration cytology (FNAC) is still considered the ‘gold standard’ method for the dia... more Fine needle aspiration cytology (FNAC) is still considered the ‘gold standard’ method for the diagnosis of thyroid cancer. In our experience, this favorable opinion of cytology has led many doctors in their clinical practice to rely almost exclusively on this method when deciding whether or not to refer a patient for surgery. As a consequence, many patients undergo surgery prompted by an ‘indeterminate’ cytological diagnosis, while others go untreated on the strength of negative cytological findings alone. The practical outcome of this behavior is that about 80% of the patients referred to the surgeon with an indeterminate cytology are found afterwards to be carrying a benign disease and their surgical procedure could have been avoided in most cases, whereas a recent review has demonstrated that cytology fails to identify a malignancy in up to 30% of patients for whom surgery would clearly be warranted [1].

Research paper thumbnail of Republished: Endovascular recanalization of the common carotid artery in a patient with radio induced chronic occlusion

Journal of NeuroInterventional Surgery, Nov 4, 2016

Recanalization of chronic occlusion of the common carotid artery (CCA) in patients with a history... more Recanalization of chronic occlusion of the common carotid artery (CCA) in patients with a history of neck irradiation is challenging, both for vascular surgeons and interventional neuroradiologists. We describe a case of successful stenting of radio induced chronic occlusion of the right CCA in a 41-year-old patient with neurological deterioration and minor stroke due to cerebral hypoperfusion caused by concomitant bilateral arterial occlusions. Direct surgery and surgical bypass were considered contraindicated. The endovascular approach was successful and required multiple precautions during the procedure. We describe particular solutions, not used in day to day practice, that allowed us to carry out the endovascular treatment in this unusual situation.

Research paper thumbnail of Successful Reperfusion is Associated with Favorable Functional Outcome despite Vessel Perforation during Thrombectomy: A Case Series and Systematic Review

American Journal of Neuroradiology, Sep 29, 2022

Research paper thumbnail of Comparison of the diagnostic accuracy of combined elastosonography and BRAF analysis vs cytology and ultrasonography for thyroid nodule suspected of malignancy

Clinical Endocrinology, Sep 11, 2012

Objective Diagnosing thyroid nodules preoperatively using traditional diagnostic toolsultrasonogr... more Objective Diagnosing thyroid nodules preoperatively using traditional diagnostic toolsultrasonography (US) and cytologystill carries a considerable degree of uncertainty, and surgery is recommended for a far from negligible number of patients simply for diagnostic purposes. Thyroid elastosonography (USE) and BRAF analysis have recently proved useful in detecting thyroid malignancies. The aim of this study is to establish whether combining USE and BRAF testing ameliorates preoperative diagnosis of thyroid nodule candidates for intervention by conventional approaches, thereby avoiding the need for diagnostic surgical procedures. Design and Patients We retrospectively analysed the files of 155 consecutive patients with 164 nodules, all assessed by ultrasonography, cytology, USE and BRAF testing, who underwent thyroid surgery. Results Of the 164 nodules, 74 (45%) were benign and 90 (55%) were malignant at final histology. Combining ultrasonography and cytology identified 21 (13%) as benign, 93 (57%) as malignant or probably malignant and 50 (30%) as 'suspended' (when the combined test was not able to classify the node as benign or malignant) with a 99% sensitivity, 28% specificity, 63% PPV, 95% NPV and 67% accuracy. Combining USE and BRAF testing indicated that 59 (36%) were benign, 74 (45%) were malignant and 31 (19%) were in a 'suspended' category, with a 95% sensitivity, 74% specificity, 82% PPV, 93% NPV and 86% accuracy. Conclusions In assessing thyroid nodules suspected of malignancy, the combined analysis of USE and BRAF is equally sensitive and more specific than conventional procedures, achieving more accurate preoperative diagnoses than US and cytology combined. USE and BRAF analysis for thyroid nodule evaluation might reduce the number of unnecessary surgical procedures.

Research paper thumbnail of Transvenous Approach for the Treatment of cerebral Arteriovenous Malformations (TATAM): Study protocol of a randomised controlled trial

Interventional Neuroradiology, Feb 4, 2019

BackgroundTransvenous embolisation is a promising technique but the benefits remain uncertain. We... more BackgroundTransvenous embolisation is a promising technique but the benefits remain uncertain. We hypothesised that transvenous embolisation leads to a higher rate of arteriovenous malformation angiographic occlusion than transarterial embolisation.MethodsThe Transvenous Approach for the Treatment of cerebral Arteriovenous Malformations (TATAM) is an investigator initiated, multicentre, prospective, phase 2, randomised controlled clinical trial. To test the hypothesis that transvenous embolisation is superior to transarterial embolisation for arteriovenous malformation obliteration, 76 patients with arteriovenous malformations considered curable by up to two sessions of endovascular therapy will be randomly allocated 1:1 to treatment with either transvenous embolisation (with or without transarterial embolisation) (experimental arm) or transarterial embolisation alone (control arm). The primary endpoint of the trial is complete arteriovenous malformation occlusion, assessed by catheter cerebral angiography. Complete occlusions will be confirmed at 3 months, while incompletely occluded arteriovenous malformations, considered treatment failures, will then be eligible for complementary treatments by surgery, radiation therapy, or even transvenous embolisation. Standard procedural safety outcomes will also be assessed. Patient selection will be validated by a case selection committee, and participating centres with limited experience in transvenous embolisation will be proctored.DiscussionThe TATAM trial is a transparent research framework designed to offer a promising but still unvalidated treatment to selected arteriovenous malformation patients.Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: {"type":"clinical-trial","attrs":{"text":"NCT03691870","term_id":"NCT03691870"}}NCT03691870.

Research paper thumbnail of A randomized pilot study of patients with tandem carotid lesions undergoing thrombectomy

Journal of Neuroradiology, Nov 1, 2020

Background and purpose.-The optimal management of patients with tandem lesions (TL), or cervical ... more Background and purpose.-The optimal management of patients with tandem lesions (TL), or cervical internal carotid artery (c-ICA) steno-occlusive pathology and ipsilateral intracranial occlusion, who are undergoing endovascular thrombectomy (EVT) remains unknown. We sought to establish the feasibility of a trial designed to address this question. Materials and methods.-The Endovascular Acute Stroke Intervention (EASI) study was a single-centre randomized trial comparing EVT to medical therapy for large-vessel occlusion stroke. Patients with TL receiving EVT were randomly allocated to acute c-ICA stenting or no stenting. The primary outcome was the proportion of patients with a modified Rankin Scale (mRS) score of 0-2 at 90 days. Safety outcomes were symptomatic intracranial hemorrhage (sICH) at 24 hours and mortality at 90 days. Results.-Of 301 patients included in EASI between 2013 and 2018, 24 (8.0%) with TL were randomly allocated to acute stenting (n = 13) or no stenting (n = 11). Baseline characteristics were balanced. Eight (61.5%; 95% CI 35.5%-82.3%) and 7 (63.6%; 95% CI 35.4%-84.9%) patients, respectively, had a favorable outcome (mRS 0-2; P = 1.0). One non-stented patient had a symptomatic intracerebral hemorrhage. Conclusions.-This pilot trial of patients with TL undergoing EVT suggests that a sufficiently powered larger TL trial comparing acute c-ICA stenting to no stenting is feasible. Clinical Trial Registration.-URL: http://www.clinicaltrials.gov. Unique identifier: NCT02157532.

Research paper thumbnail of Stent-Assisted Coiling in the Treatment of Unruptured Intracranial Aneurysms: A Randomized Clinical Trial

American Journal of Neuroradiology, Mar 16, 2023

BACKGROUND AND PURPOSE: Stent-assisted coiling may improve angiographic results of endovascular t... more BACKGROUND AND PURPOSE: Stent-assisted coiling may improve angiographic results of endovascular treatment of unruptured intracranial aneurysms compared with coiling alone, but this has never been shown in a randomized trial. MATERIALS AND METHODS: The Stenting in the Treatment of Aneurysm Trial was an investigator-led, parallel, randomized (1:1) trial conducted in 4 university hospitals. Patients with intracranial aneurysms at risk of recurrence, defined as large aneurysms ($10 mm), postcoiling recurrent aneurysms, or small aneurysms with a wide neck ($4 mm), were randomly allocated to stent-assisted coiling or coiling alone. The composite primary efficacy outcome was "treatment failure," defined as initial failure to treat the aneurysm; aneurysm rupture or retreatment during follow-up; death or dependency (mRS. 2); or an angiographic residual aneurysm adjudicated by an independent core laboratory at 12 months. The primary hypothesis (revised for slow accrual) was that stent-assisted coiling would decrease treatment failures from 33% to 15%, requiring 200 patients. Primary analyses were intent to treat. RESULTS: Of 205 patients recruited between 2011 and 2021, ninety-four were allocated to stent-assisted coiling and 111 to coiling alone. The primary outcome, ascertainable in 203 patients, was reached in 28/93 patients allocated to stent-assisted coiling (30.1%; 95% CI, 21.2%-40.6%) compared with 30/110 (27.3%; 95% CI, 19.4%-36.7%) allocated to coiling alone (relative risk ¼ 1.10; 95% CI, 0.7-1.7; P ¼ .66). Poor clinical outcomes (mRS .2) occurred in 8/94 patients allocated to stent-assisted coiling (8.5%; 95% CI, 4.0%-16.6%) compared with 6/111 (5.4%; 95% CI, 2.2%-11.9%) allocated to coiling alone (relative risk ¼ 1.6; 95% CI, 0.6%-4.4%; P ¼ .38).

Research paper thumbnail of Endovascular recanalization of the common carotid artery in a patient with radio induced chronic occlusion

Case Reports, Nov 1, 2016

Research paper thumbnail of Patient Selection in a Pragmatic Study on the Management of Patients with Brain Arteriovenous Malformations

Research paper thumbnail of Successful Reperfusion is Associated with Favorable Functional Outcome despite Vessel Perforation during Thrombectomy: A Case Series and Systematic Review

American Journal of Neuroradiology

Research paper thumbnail of Surgical treatment of brain arteriovenous malformations: clinical outcomes of patients included in the registry of a pragmatic randomized trial

Journal of Neurosurgery

OBJECTIVE The Treatment of Brain Arteriovenous Malformations Study (TOBAS) is a pragmatic study t... more OBJECTIVE The Treatment of Brain Arteriovenous Malformations Study (TOBAS) is a pragmatic study that includes 2 randomized trials and registries of treated or conservatively managed patients. The authors report the results of the surgical registry. METHODS TOBAS patients are managed according to an algorithm that combines clinical judgment and randomized allocation. For patients considered for curative treatment, clinicians selected from surgery, endovascular therapy, or radiation therapy as the primary curative method, and whether observation was a reasonable alternative. When surgery was selected and observation was deemed unreasonable, the patient was not included in the randomized controlled trial but placed in the surgical registry. The primary outcome of the trial was mRS score > 2 at 10 years (at last follow-up for the current report). Secondary outcomes include angiographic results, perioperative serious adverse events, and permanent treatment-related complications leadin...

Research paper thumbnail of Thrombectomy alone versus intravenous alteplase plus thrombectomy in patients with stroke: an open-label, blinded-outcome, randomised non-inferiority trial

Research paper thumbnail of Reliability of CT Angiography in Cerebral Vasospasm: A Systematic Review of the Literature and an Inter- and Intraobserver Study

American Journal of Neuroradiology, 2020

BACKGROUND AND PURPOSE: Computed tomography angiography offers a non-invasive alternative to DSA ... more BACKGROUND AND PURPOSE: Computed tomography angiography offers a non-invasive alternative to DSA for the assessment of cerebral vasospasm following subarachnoid hemorrhage but there is limited evidence regarding its reliability. Our aim was to perform a systematic review (Part I) and to assess (Part II) the inter-and intraobserver reliability of CTA in the diagnosis of cerebral vasospasm. MATERIALS AND METHODS: In Part I, articles reporting the reliability of CTA up to May 2018 were systematically searched and evaluated. In Part II, 11 raters independently graded 17 arterial segments in each of 50 patients with SAH for the presence of vasospasm using a 4-category scale. Raters were additionally asked to judge the presence of any moderate/severe vasospasm ($ 50% narrowing) and whether findings would justify augmentation of medical treatment or conventional angiography 6 balloon angioplasty. Four raters took part in the intraobserver reliability study. RESULTS: In Part I, the systematic review revealed few studies with heterogeneous vasospasm definitions. In Part II, we found interrater reliability to be moderate at best (k # 0.6), even when results were stratified according to specialty and experience. Intrarater reliability was substantial (k. 0.6) in 3/4 readers. In the per arterial segment analysis, substantial agreement was reached only for the middle cerebral arteries, and only when senior raters' judgments were dichotomized (presence or absence of $50% narrowing). Agreement on the medical or angiographic management of vasospasm based on CTA alone was less than substantial (k # 0.6). CONCLUSIONS: The diagnosis of vasospasm using CTA alone was not sufficiently repeatable among observers to support its general use to guide decisions in the clinical management of patients with SAH.

Research paper thumbnail of Pénétration de cyanoacrylates d’alpha-hexil et de n-butyle à l’aide de la technique modifiée de « pressure cooker technique » : une étude expérimentale chez l’animal

Journal of Neuroradiology, 2019

photonique) ont révélé que le greffage du peptide P8RI améliore la qualité de son endothélialisat... more photonique) ont révélé que le greffage du peptide P8RI améliore la qualité de son endothélialisation avec une meilleure intégration du dispositif à l'interface sang-vaisseaux. Aucune occlusion de branche artérielle couverte par le dispositif n'a été observée. Conclusion Ces résultats constituent une étape cruciale en vue d'un passage à l'Homme. Cette technique de recouvrement pourra être proposé également pour les autres dispositifs intra-artériels utilisés en neuroradiologie interventionnelle. Mots clés Flow-diverter ; Recourvrement/coating ; P8RI ; CD31. Déclaration de liens d'intérêts Les auteurs déclarent ne pas avoir de liens d'intéreˆts.

Research paper thumbnail of Stent-Assisted Coiling in the Treatment of Unruptured Intracranial Aneurysms: A Randomized Clinical Trial

American Journal of Neuroradiology

BACKGROUND AND PURPOSE: Stent-assisted coiling may improve angiographic results of endovascular t... more BACKGROUND AND PURPOSE: Stent-assisted coiling may improve angiographic results of endovascular treatment of unruptured intracranial aneurysms compared with coiling alone, but this has never been shown in a randomized trial. MATERIALS AND METHODS: The Stenting in the Treatment of Aneurysm Trial was an investigator-led, parallel, randomized (1:1) trial conducted in 4 university hospitals. Patients with intracranial aneurysms at risk of recurrence, defined as large aneurysms ($10 mm), postcoiling recurrent aneurysms, or small aneurysms with a wide neck ($4 mm), were randomly allocated to stent-assisted coiling or coiling alone. The composite primary efficacy outcome was "treatment failure," defined as initial failure to treat the aneurysm; aneurysm rupture or retreatment during follow-up; death or dependency (mRS. 2); or an angiographic residual aneurysm adjudicated by an independent core laboratory at 12 months. The primary hypothesis (revised for slow accrual) was that stent-assisted coiling would decrease treatment failures from 33% to 15%, requiring 200 patients. Primary analyses were intent to treat. RESULTS: Of 205 patients recruited between 2011 and 2021, ninety-four were allocated to stent-assisted coiling and 111 to coiling alone. The primary outcome, ascertainable in 203 patients, was reached in 28/93 patients allocated to stent-assisted coiling (30.1%; 95% CI, 21.2%-40.6%) compared with 30/110 (27.3%; 95% CI, 19.4%-36.7%) allocated to coiling alone (relative risk ¼ 1.10; 95% CI, 0.7-1.7; P ¼ .66). Poor clinical outcomes (mRS .2) occurred in 8/94 patients allocated to stent-assisted coiling (8.5%; 95% CI, 4.0%-16.6%) compared with 6/111 (5.4%; 95% CI, 2.2%-11.9%) allocated to coiling alone (relative risk ¼ 1.6; 95% CI, 0.6%-4.4%; P ¼ .38).

Research paper thumbnail of O-031 Is flow diversion the best treatment of cavernous carotid aneurysms?

Oral Abstracts, 2018

Background and Purpose Cavernous carotid aneurysms can cause pain and ophtalmoplegia from mass ef... more Background and Purpose Cavernous carotid aneurysms can cause pain and ophtalmoplegia from mass effect, but they rarely rupture or cause life threatening complications. Treatment options include observation, parent vessel occlusion, coil embolization, or in the last decade flow-diversion (FD). We aimed to compare the results of FD with more conventional treatments in patients with cavernous aneurysms recruited in the Flow Diverter in the Treatment of Aneurysms trial (FIAT). Materials and methods FIAT, conducted in 3 Canadian hospitals, proposed randomized allocation to flow diversion or standard management options (observation, coil embolization, parent vessel occlusion, or clip placement), and a registry of nonrandomized patients treated with flow diversion. The primary safety outcome was death or dependency (modified Rankin Scale score >2) at 3 months, to be determined for all patients who received flow diversion at any time. The primary efficacy outcome was angiographic occlusion at 3–12 months combined with an independent clinical outcome. Results Forty-two patients with cavernous aneurysms were included in the FIAT study. In 31 patients, treatment was randomly allocated: 17 were treated with FD, 14 using best standard treatment (BST). Eleven patients treated with FD were judged untreatable otherwise. An hemorrhagic complication occurred in 3/28 patients treated with FD (11%; 3.7%–27.2%), as compared to 0/14 with BST (0%–21.5%) Overall, we had a 3% mortality rate and a 7% major neurologic complication rate. Conclusion Flow diversion in CCAs was not safe as hypothesized. We observed unusual and potentially fatal hemorrhagic complications in patients treated with FD that need to be attentively analyzed, especially considered that CCAs hemorrhagic presentation is a rare event. More randomized trials are needed to determine the role of flow diversion in the management of cavernous carotid aneurysms. Disclosures L. Nico: 1; C; Medtronic-Covidien. A. Weill: None. D. Roy: None. J. Raymond: None.

Research paper thumbnail of Exophtalmie aiguë après thrombectomie mécanique pour occlusion intracrânienne: une étude rétrospective

Journal of Neuroradiology, 2019

Research paper thumbnail of Angiographic results of surgical or endovascular treatment of intracranial aneurysms: a systematic review and inter-observer reliability study

Neuroradiology

Results of surgical or endovascular treatment of intracranial aneurysms are often assessed using ... more Results of surgical or endovascular treatment of intracranial aneurysms are often assessed using angiography. A reliable method to report results irrespective of treatment modality is needed to enable comparisons. Our goals were to systematically review existing classification systems, and to propose a 3-point classification applicable to both treatments and assess its reliability. We conducted two systematic reviews on classification systems of angiographic results after clipping or coiling to select a simple 3-category scale that could apply to both treatments. We then circulated an electronic portfolio of angiograms of clipped (n=30) or coiled (n=30) aneurysms, and asked raters to evaluate the degree of occlusion using this scale. Raters were also asked to choose an appropriate follow-up management for each patient based on the degree of occlusion. Agreement was assessed using Krippendorff’s α statistics (αK), and relationship between occlusion grade and clinical management was analyzed using Fisher’s exact and Cramer’s V tests. The systematic reviews found 70 different grading scales with heterogeneous reliability (kappa values from 0.12 to 1.00). The 60-patient portfolio was independently evaluated by 19 raters of diverse backgrounds (neurosurgery, radiology, and neurology) and experience. There was substantial agreement (αK=0.76, 95%CI, 0.67–0.83) between raters, regardless of background, experience, or treatment used. Intra-rater agreement ranged from moderate to almost perfect. A strong relationship was found between angiographic grades and management decisions (Cramer’s V: 0.80±0.12). A simple 3-point scale demonstrated sufficient reliability to be used in reporting aneurysm treatments or in evaluating treatment results in comparative randomized trials.

Research paper thumbnail of Comparing N-hexyl cyanoacrylate (Magic Glue) and N-butyl cyanoacrylate (NBCA) for neurovascular embolization using the pressure cooker technique: An experimental study in swine

Journal of Neuroradiology

BACKGROUND The pressure cooker (PC) technique uses a second microcatheter to produce a proximal o... more BACKGROUND The pressure cooker (PC) technique uses a second microcatheter to produce a proximal occlusion to prevent the reflux of liquid embolic agent (LEA) injected through a more distal microcatheter, and can be used to treat arteriovenous malformations and dural arteriovenous fistulae. The liquid embolic Magic Glue (MG) (N-hexyl cyanoacrylate (NHCA)) has been introduced as an alternative to N-butyl cyanoacrylate (NBCA). Our goals were to compare the extent of embolization of rete mirabile with or without the PC technique using NBCA or MG, and to compare the proximal occlusions obtained with MG or NBCA while using the PC technique in a renal arterial model. METHODS Rete mirabile were embolized with (n = 4) and without (n = 4) the PC technique, using MG (n = 4) or NBCA (n = 4). A renal arterial model was then used to study the characteristics of the MG plug (n = 10) used for the PC technique, and resistance to catheter withdrawal as compared to NBCA (n = 4). Specimens were analyzed macro- and microscopically and compared to angiographic results. RESULTS Extent of rete embolization with CYA agents was not significantly greater when using the PC technique. Results were similar with both types of cyanoacrylate (p = 0.657). The force necessary to withdraw the microcatheter was less with MG than with NBCA (p = 0.035). CONCLUSION MG was similar to NBCA in extent of rete embolization. Less traction force was necessary to withdraw trapped non-detachable microcatheters using MG compared to NBCA.