Evelyne Emery - Academia.edu (original) (raw)

Papers by Evelyne Emery

Neurorehabilitation and neural repair, Jan 29, 2015

Nearly 15 million people suffer from stroke every year worldwide, with about 20% of the survivors... more Nearly 15 million people suffer from stroke every year worldwide, with about 20% of the survivors retaining chronic aphasic symptoms. Spontaneous recovery is limited to 3 to 6 months. Cortical stimulation techniques have been proposed to enhance the recovery process. The goal of this study was to evaluate the benefit of epidural cortical stimulation for the treatment of poststroke aphasia, based on a systematic review of the literature. An extensive PubMed search was performed for English language articles published from 1990 to 2014 with the keywords (cortical OR epidural) AND stimulation AND stroke AND (aphasia OR language OR speech). The criteria analyzed included the type of study, epidemiology of patients, stroke, aphasia, stimulation protocol, concurrent rehabilitation therapies, language evaluations, results observed, and follow-up. Seven cases were reported to date (3 case reports, 1 randomized controlled trial). All patients experienced nonfluent aphasia following an ischem...

World neurosurgery, Jan 23, 2015

To compare surgical clipping to endovascular coiling in terms of recovery from oculomotor nerve p... more To compare surgical clipping to endovascular coiling in terms of recovery from oculomotor nerve palsy (ONP) in the management of posterior communicating artery (PCoA) aneurysms causing third nerve palsy. The authors conducted a systematic review of the literature and meta-analysis. Eleven relevant studies involving a total of 384 patients with third nerve palsy due to PCoA aneurysms at baseline, of whom 257 (67.0%) were treated by clipping and 127 by coiling (33.0%), were included in a meta-analysis. Pooled Odds Ratios of the impact of clipping or coiling on complete ONP recovery, lack of ONP recovery and procedure-related death were calculated. The overall complete ONP recovery rate was 42.5% in the coiling group compared to 83.6% in the clipping group. The increase in complete ONP recovery in the clipping group corresponds to an overall pooled Mantel-Haenzel odds ratio of 4.44 (95% CI 1.66-11.84). Subgroup analysis revealed a clear benefit of clipping over coiling in patients with...

Neuro-Oncology, 2015

These authors (P.M. and P.M.) participated equally in this work.

World neurosurgery, 2014

Since the mid-1950s, neurosurgery has benefited from the remarkable progress due to tremendous ad... more Since the mid-1950s, neurosurgery has benefited from the remarkable progress due to tremendous advances in neuroimaging techniques, neuroanesthesia, neurostimulation, and brain-computer interfaces, as well as breakthroughs in operating microscopes and surgical instruments. Yet, this specialty has to do with delicate human structures and is hence considered as highly risky by insurance companies. In France, although neurosurgery's casualty rate (6%) is lower than in other specialties, the number of legal prosecutions has increased since 2002 because of easier access to medicolegal procedures. In order to avoid patients' resorting to the law courts, it becomes necessary to clearly identify the risk factors. From the data bank of the insurer Société Hospitalière d'Assurances Mutuelles (SHAM, main insurance company for public hospitals in France), we retrospectively analyzed 115 files (34 cranial and 81 spinal surgeries) covering the period 1997-2007 for the reasons for comp...

Stroke; a journal of cerebral circulation, 2014

The aim of the present study was to investigate the impact of different stroke subtypes on the gl... more The aim of the present study was to investigate the impact of different stroke subtypes on the glymphatic system using MRI. We first improved and characterized an in vivo protocol to measure the perfusion of the glymphatic system using MRI after minimally invasive injection of a gadolinium chelate within the cisterna magna. Then, the integrity of the glymphatic system was evaluated in 4 stroke models in mice including subarachnoid hemorrhage (SAH), intracerebral hemorrhage, carotid ligature, and embolic ischemic stroke. We were able to reliably evaluate the glymphatic system function using MRI. Moreover, we provided evidence that the glymphatic system was severely impaired after SAH and in the acute phase of ischemic stroke, but was not altered after carotid ligature or in case of intracerebral hemorrhage. Notably, this alteration in glymphatic perfusion reduced brain clearance rate of low-molecular-weight compounds. Interestingly, glymphatic perfusion after SAH can be improved by i...

Surgical Neurology, 2008

Prevalence of cerebral cavernomas in the general population is close to 0.5%. In contrast, SCCs a... more Prevalence of cerebral cavernomas in the general population is close to 0.5%. In contrast, SCCs are rare. The aim of this study was to determine the outcome of SCC in a large sample of patients. Clinical and neuroradiologic findings were retrospectively collected in a multicentric study. Diagnosis was based on pathologic criteria or MR findings. Fifty-three patients were included (26 males, 27 females). Mean age at onset of symptoms was 40.2 years (11-80 years). Initial symptoms were progressive (32) or acute myelopathy (20). One case was asymptomatic. Triggering factors were found in 14 of the patients (26%). Clinical symptoms were related to spinal cord compression (27) and hemorrhage (22). Spinal cord cavernoma was thoracic in 41 cases and cervical in 12. Mean size of the lesions was 16.3 mm (3-54 mm). In the 40 surgical patients, long-term follow-up was available in 37 cases for a mean time of 7.3 years (0.4-50 years). During the follow-up period, 20 patients improved, 6 remained on their preoperative baseline, and 11 got worse. Surgical improvement was more often found in posterior rather than anterior location. Using McCormick classification, 22 patients were autonomous (grades 1-2), 12 handicapped (grade 3), and 3 bedridden (grade 4) at the end of the follow-up. This study has defined clinical and MR patterns of spinal cavernomas. Surgery lastingly improved more than half of the patients.

Neuropharmacology, 2014

Intraventricular hemorrhage (IVH) is the most severe form of stroke with intraventricular fibrino... more Intraventricular hemorrhage (IVH) is the most severe form of stroke with intraventricular fibrinolysis (IVF) as a hopeful treatment. Urokinase (uPA) and tissue-type plasminogen activator (tPA) are used for IVF in Human. No clinical trial has evaluated the differential impact of these two fibrinolytics for IVF. Thus, we decided here to compare the use of these two fibrinolytics in a pre-clinical study. IVH was induced in rats by injection of collagenase type VII within the brain parenchyma followed by an IVF. Rats were randomized to receive uPA, tPA or saline within the ventricle, and cerebrospinal fluid was aspirated. Hematoma and ventricular volumes, brain water contents, inflammation and neurological deficits were measured at day three post-treatments. We also performed in vitro studies, in which neuronal cultures were subjected to an excitotoxic paradigm in the presence of either uPA or tPA. In the IVH model, we showed that although both uPA and tPA led to reduced ventricular volumes, only uPA significantly improved functional recovery. These results could be explained by the fact that uPA, in contrast of tPA, fails to promote inflammatory processes and neurotoxicity. Our study provides evidence supporting the use of uPA for fibrinolysis of IVH. A clinical trial could be warranted if tPA failed to improve outcomes in human IVH.

Neuropharmacology, 2013

Ischemic and hemorrhagic strokes have different etiologies, but share some pathogenic mechanisms,... more Ischemic and hemorrhagic strokes have different etiologies, but share some pathogenic mechanisms, including a pro-neurotoxic effect of endogenous tissue plasminogen activator (tPA) via N-methyl-D-Aspartate (NMDA) receptors. Thus, in a model of intracerebral hemorrhage in rats, we investigated the therapeutic value of a strategy of immunotherapy (aATD-GluN1 antibody) preventing the interaction of tPA with NMDA receptors. We found that a single intravenous injection of aATD-GluN1 reduced brain edema, neuronal death, microglial activation and functional deficits following intracerebral hemorrhage, without affecting the hematoma volume.

Neurobiology of Disease, 2014

Although tissue plasminogen activator (tPA) is known to promote neuronal remodeling in the CNS, n... more Although tissue plasminogen activator (tPA) is known to promote neuronal remodeling in the CNS, no mechanism of how this plastic function takes place has been reported so far. We provide here in vitro and in vivo demonstrations that this serine protease neutralizes inhibitory chondroitin sulfate proteoglycans (CSPGs) by promoting their degradation via the direct activation of endogenous type 4 disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS-4). Accordingly, in a model of compression-induced spinal cord injury (SCI) in rats, we found that administration of either tPA or its downstream effector ADAMTS-4 restores the tPA-dependent activity lost after the SCI and thereby, reduces content of CSPGs in the spinal cord, a cascade of events leading to an improved axonal regeneration/sprouting and eventually long term functional recovery. This is the first study to reveal a tPA-ADAMTS-4 axis and its function in the CNS. It also raises the prospect of exploiting such cooperation as a therapeutic tool for enhancing recovery after acute CNS injuries.

European Spine Journal, 2011

We read with great interest the article written by Liu et al. This retrospective study included p... more We read with great interest the article written by Liu et al. This retrospective study included patients with type A or C according AO classification non-osteoporosis thoracolumbar fractures. They were treated with posterior fixation without fusion after indirect reduction. Almost all patients had instrumentation removal at 9-12 months post-operative. The authors report good long-term outcome for the great majority of included patients.

British Journal of Neurosurgery, 2012

Ruptured anterior communicating artery aneurysm presenting with complete third nerve palsy is gen... more Ruptured anterior communicating artery aneurysm presenting with complete third nerve palsy is genuinely rare. We herein report one such case resulting from an interpeduncular haematoma. Three months after the coiling, the patient had fully recovered. This case adds a new branch to the aetiology-to-prognostic decision-making tree of third nerve palsies.

Brain Stimulation, 2012

Aphasia is an incapacitating deficit experienced by almost 25% of patients after a left hemispher... more Aphasia is an incapacitating deficit experienced by almost 25% of patients after a left hemispheric ischemic stroke. Spontaneous recovery is considered to be limited to a period of 3 to 6 months. Although speech therapy performed during the first weeks may speed up this process and enhance its outcome, beyond this period it fails to change the global prognosis. We report a case of an unusual recovery of nonfluent chronic poststroke aphasia subsequent to extradural cortical stimulation. A right-handed woman experienced aphasia and drug-resistant central poststroke facial pain after a left superficial Sylvian ischemic stroke at the age of 58 years old. Four years after the stroke, the patient was included in a clinical trial to establish the efficiency of epidural electric stimulation on neuropathic pain. As an improvement in her language performance was noted, a speech evaluation was added to the initial protocol to quantify the benefit. Twelve months after the surgical implantation, pain and language performance were assessed in a double-blind manner during two consecutive 1-month periods when the stimulator was randomly enabled or disabled. The same evaluation was performed after 5 years of stimulation. Eventually, epidural electric stimulation significantly and sustainably improved her lexical access and speech fluency. Cortical stimulation may offer a new approach for the treatment of late chronic poststroke aphasia.

Acta Neurochirurgica, 2010

Tentorial dural arteriovenous fistulas are rare and complex lesions in deep locations with unusua... more Tentorial dural arteriovenous fistulas are rare and complex lesions in deep locations with unusual vascular anatomy and critical surrounding neuroanatomy. A rare case presenting a complex fistula with a giant venous draining ampulae, causing headaches and visual troubles is presented. We describe the case of a 52-year-old woman admitted in our department for headaches and visual troubles. Magnetic resonance imaging and cerebral angiography showed a tentorial dural arteriovenous fistula draining in a giant tentorial venous ampulae and leptomeningeal veins. The patient was embolised via an arterial route with a good clinical and radiological result. However, 4 days later she presented a sudden change of her clinical status with coma, left hemiparesis and a right midriasis. The cerebral computed tomography scan showed a huge occipital haemorrhagic mass and a severe cerebral oedema. An emergent surgical procedure was decided realising evacuation of the occipital haematoma and a complete resection of the giant venous ampoule. The neck of the ampulae was sutured and clipped at its dural entrance. Postoperatively a new embolisation was realised because of persistent of a small dural fistulae with occipital leptomeningeal drainage. The patient recovered rapidly with only a residual hemianopsy. Treatment of dural AV malformation represent a serious challenge. Our report describes an unusual case of a tentorial dural complex fistula treated by an endovascular procedure with secondary clinical aggravation that needed emergent surgical therapy. Even in a case for good immediate radiological result after endovascular procedure, dural arteriovenous fistulas with giant venous ampulae and important venous engorgement, need closed follow-up, because of the possibility of aggravation secondary to venous thrombosis and haemorrhage. Treatment and patophysiology of the aggravation mechanism are discussed.

Acta Neurochirurgica, 2010

Purpose Surgical treatment of cavernomas arising in the insula (especially in dominant cerebral h... more Purpose Surgical treatment of cavernomas arising in the insula (especially in dominant cerebral hemisphere) is challenging in reason of the proximity to the internal capsule and lenticulostriate arteries. The advent of image guidance systems and intraoperative mapping of the subcortical language pathways has broadened the surgical indications for these lesions. In this work, we report four cases of insular cavernomas operated on, and we define a surgical strategy for these lesions. Methods Between in our department, four patients harboring an insular cavernoma were operated on by using image guidance system (neuronavigation in three cases, ultrasound in one case). Subcortical stimulations were used to preserve the functional language area in one case. Findings The image guidance system determined the exact planning of the approach and determination of the ideal trajectory of insular cortex dissection. In a case of a deep left insular cavernoma, the shortest approach to remove the cavernoma was stopped in per-operative time because subcortical stimulation produced a speech inhibition, justifying another insular corticotomy. No surgical complications occurred, and the postoperative course was uneventful in all patients. Conclusion As it has been proposed by many authors, image guidance system is recommended in surgery of insular cavernomas. When the lesion is located in the dominant hemisphere, intraoperative mapping of the subcortical language pathways is also indicated to preserve the language functional areas.

PLoS ONE, 2013

Spinal cord injury (SCI) induces a permanent disability in patients. To this day no curative trea... more Spinal cord injury (SCI) induces a permanent disability in patients. To this day no curative treatment can be proposed to restore lost functions. Therefore, extensive experimental studies have been conducted to induce recovery after SCI. One of the most promising therapies is based on the use of olfactory ensheathing cells (OECs). OECs can be obtained from either the olfactory bulbs (OB-OECs) or from olfactory mucosa (OM-OECs), involving a less invasive approach for autotransplantation. However the vast majority of experimental transplantations have been focusing on OB-OECs although the OM represents a more accessible source of OECs. Importantly, the ability of OM-OECs in comparison to OB-OECs to induce spinal cord recovery in the same lesion paradigm has never been described. We here present data using a multiparametric approach, based on electrophysiological, behavioral, histological and magnetic resonance imaging experiments on the repair potential of OB-OECs and OM-OECs from either primary or purified cultures after a severe model of SCI. Our data demonstrate that transplantation of OECs obtained from OB or OM induces electrophysiological and functional recovery, reduces astrocyte reactivity and glial scar formation and improves axonal regrowth. We also show that the purification step is essential for OM-OECs while not required for OB-OECs. Altogether, our study strongly indicates that transplantation of OECs from OM represents the best benefit/risk ratio according to the safety of access of OM and the results induced by transplantations of OM-OECs. Indeed, purified OM-OECs in addition to induce recovery can integrate and survive up to 60 days into the spinal cord. Therefore, our results provide strong support for these cells as a viable therapy for SCI.

Neurorehabilitation and neural repair, Jan 29, 2015

Nearly 15 million people suffer from stroke every year worldwide, with about 20% of the survivors... more Nearly 15 million people suffer from stroke every year worldwide, with about 20% of the survivors retaining chronic aphasic symptoms. Spontaneous recovery is limited to 3 to 6 months. Cortical stimulation techniques have been proposed to enhance the recovery process. The goal of this study was to evaluate the benefit of epidural cortical stimulation for the treatment of poststroke aphasia, based on a systematic review of the literature. An extensive PubMed search was performed for English language articles published from 1990 to 2014 with the keywords (cortical OR epidural) AND stimulation AND stroke AND (aphasia OR language OR speech). The criteria analyzed included the type of study, epidemiology of patients, stroke, aphasia, stimulation protocol, concurrent rehabilitation therapies, language evaluations, results observed, and follow-up. Seven cases were reported to date (3 case reports, 1 randomized controlled trial). All patients experienced nonfluent aphasia following an ischem...

World neurosurgery, Jan 23, 2015

To compare surgical clipping to endovascular coiling in terms of recovery from oculomotor nerve p... more To compare surgical clipping to endovascular coiling in terms of recovery from oculomotor nerve palsy (ONP) in the management of posterior communicating artery (PCoA) aneurysms causing third nerve palsy. The authors conducted a systematic review of the literature and meta-analysis. Eleven relevant studies involving a total of 384 patients with third nerve palsy due to PCoA aneurysms at baseline, of whom 257 (67.0%) were treated by clipping and 127 by coiling (33.0%), were included in a meta-analysis. Pooled Odds Ratios of the impact of clipping or coiling on complete ONP recovery, lack of ONP recovery and procedure-related death were calculated. The overall complete ONP recovery rate was 42.5% in the coiling group compared to 83.6% in the clipping group. The increase in complete ONP recovery in the clipping group corresponds to an overall pooled Mantel-Haenzel odds ratio of 4.44 (95% CI 1.66-11.84). Subgroup analysis revealed a clear benefit of clipping over coiling in patients with...

Neuro-Oncology, 2015

These authors (P.M. and P.M.) participated equally in this work.

World neurosurgery, 2014

Since the mid-1950s, neurosurgery has benefited from the remarkable progress due to tremendous ad... more Since the mid-1950s, neurosurgery has benefited from the remarkable progress due to tremendous advances in neuroimaging techniques, neuroanesthesia, neurostimulation, and brain-computer interfaces, as well as breakthroughs in operating microscopes and surgical instruments. Yet, this specialty has to do with delicate human structures and is hence considered as highly risky by insurance companies. In France, although neurosurgery's casualty rate (6%) is lower than in other specialties, the number of legal prosecutions has increased since 2002 because of easier access to medicolegal procedures. In order to avoid patients' resorting to the law courts, it becomes necessary to clearly identify the risk factors. From the data bank of the insurer Société Hospitalière d'Assurances Mutuelles (SHAM, main insurance company for public hospitals in France), we retrospectively analyzed 115 files (34 cranial and 81 spinal surgeries) covering the period 1997-2007 for the reasons for comp...

Stroke; a journal of cerebral circulation, 2014

The aim of the present study was to investigate the impact of different stroke subtypes on the gl... more The aim of the present study was to investigate the impact of different stroke subtypes on the glymphatic system using MRI. We first improved and characterized an in vivo protocol to measure the perfusion of the glymphatic system using MRI after minimally invasive injection of a gadolinium chelate within the cisterna magna. Then, the integrity of the glymphatic system was evaluated in 4 stroke models in mice including subarachnoid hemorrhage (SAH), intracerebral hemorrhage, carotid ligature, and embolic ischemic stroke. We were able to reliably evaluate the glymphatic system function using MRI. Moreover, we provided evidence that the glymphatic system was severely impaired after SAH and in the acute phase of ischemic stroke, but was not altered after carotid ligature or in case of intracerebral hemorrhage. Notably, this alteration in glymphatic perfusion reduced brain clearance rate of low-molecular-weight compounds. Interestingly, glymphatic perfusion after SAH can be improved by i...

Surgical Neurology, 2008

Prevalence of cerebral cavernomas in the general population is close to 0.5%. In contrast, SCCs a... more Prevalence of cerebral cavernomas in the general population is close to 0.5%. In contrast, SCCs are rare. The aim of this study was to determine the outcome of SCC in a large sample of patients. Clinical and neuroradiologic findings were retrospectively collected in a multicentric study. Diagnosis was based on pathologic criteria or MR findings. Fifty-three patients were included (26 males, 27 females). Mean age at onset of symptoms was 40.2 years (11-80 years). Initial symptoms were progressive (32) or acute myelopathy (20). One case was asymptomatic. Triggering factors were found in 14 of the patients (26%). Clinical symptoms were related to spinal cord compression (27) and hemorrhage (22). Spinal cord cavernoma was thoracic in 41 cases and cervical in 12. Mean size of the lesions was 16.3 mm (3-54 mm). In the 40 surgical patients, long-term follow-up was available in 37 cases for a mean time of 7.3 years (0.4-50 years). During the follow-up period, 20 patients improved, 6 remained on their preoperative baseline, and 11 got worse. Surgical improvement was more often found in posterior rather than anterior location. Using McCormick classification, 22 patients were autonomous (grades 1-2), 12 handicapped (grade 3), and 3 bedridden (grade 4) at the end of the follow-up. This study has defined clinical and MR patterns of spinal cavernomas. Surgery lastingly improved more than half of the patients.

Neuropharmacology, 2014

Intraventricular hemorrhage (IVH) is the most severe form of stroke with intraventricular fibrino... more Intraventricular hemorrhage (IVH) is the most severe form of stroke with intraventricular fibrinolysis (IVF) as a hopeful treatment. Urokinase (uPA) and tissue-type plasminogen activator (tPA) are used for IVF in Human. No clinical trial has evaluated the differential impact of these two fibrinolytics for IVF. Thus, we decided here to compare the use of these two fibrinolytics in a pre-clinical study. IVH was induced in rats by injection of collagenase type VII within the brain parenchyma followed by an IVF. Rats were randomized to receive uPA, tPA or saline within the ventricle, and cerebrospinal fluid was aspirated. Hematoma and ventricular volumes, brain water contents, inflammation and neurological deficits were measured at day three post-treatments. We also performed in vitro studies, in which neuronal cultures were subjected to an excitotoxic paradigm in the presence of either uPA or tPA. In the IVH model, we showed that although both uPA and tPA led to reduced ventricular volumes, only uPA significantly improved functional recovery. These results could be explained by the fact that uPA, in contrast of tPA, fails to promote inflammatory processes and neurotoxicity. Our study provides evidence supporting the use of uPA for fibrinolysis of IVH. A clinical trial could be warranted if tPA failed to improve outcomes in human IVH.

Neuropharmacology, 2013

Ischemic and hemorrhagic strokes have different etiologies, but share some pathogenic mechanisms,... more Ischemic and hemorrhagic strokes have different etiologies, but share some pathogenic mechanisms, including a pro-neurotoxic effect of endogenous tissue plasminogen activator (tPA) via N-methyl-D-Aspartate (NMDA) receptors. Thus, in a model of intracerebral hemorrhage in rats, we investigated the therapeutic value of a strategy of immunotherapy (aATD-GluN1 antibody) preventing the interaction of tPA with NMDA receptors. We found that a single intravenous injection of aATD-GluN1 reduced brain edema, neuronal death, microglial activation and functional deficits following intracerebral hemorrhage, without affecting the hematoma volume.

Neurobiology of Disease, 2014

Although tissue plasminogen activator (tPA) is known to promote neuronal remodeling in the CNS, n... more Although tissue plasminogen activator (tPA) is known to promote neuronal remodeling in the CNS, no mechanism of how this plastic function takes place has been reported so far. We provide here in vitro and in vivo demonstrations that this serine protease neutralizes inhibitory chondroitin sulfate proteoglycans (CSPGs) by promoting their degradation via the direct activation of endogenous type 4 disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS-4). Accordingly, in a model of compression-induced spinal cord injury (SCI) in rats, we found that administration of either tPA or its downstream effector ADAMTS-4 restores the tPA-dependent activity lost after the SCI and thereby, reduces content of CSPGs in the spinal cord, a cascade of events leading to an improved axonal regeneration/sprouting and eventually long term functional recovery. This is the first study to reveal a tPA-ADAMTS-4 axis and its function in the CNS. It also raises the prospect of exploiting such cooperation as a therapeutic tool for enhancing recovery after acute CNS injuries.

European Spine Journal, 2011

We read with great interest the article written by Liu et al. This retrospective study included p... more We read with great interest the article written by Liu et al. This retrospective study included patients with type A or C according AO classification non-osteoporosis thoracolumbar fractures. They were treated with posterior fixation without fusion after indirect reduction. Almost all patients had instrumentation removal at 9-12 months post-operative. The authors report good long-term outcome for the great majority of included patients.

British Journal of Neurosurgery, 2012

Ruptured anterior communicating artery aneurysm presenting with complete third nerve palsy is gen... more Ruptured anterior communicating artery aneurysm presenting with complete third nerve palsy is genuinely rare. We herein report one such case resulting from an interpeduncular haematoma. Three months after the coiling, the patient had fully recovered. This case adds a new branch to the aetiology-to-prognostic decision-making tree of third nerve palsies.

Brain Stimulation, 2012

Aphasia is an incapacitating deficit experienced by almost 25% of patients after a left hemispher... more Aphasia is an incapacitating deficit experienced by almost 25% of patients after a left hemispheric ischemic stroke. Spontaneous recovery is considered to be limited to a period of 3 to 6 months. Although speech therapy performed during the first weeks may speed up this process and enhance its outcome, beyond this period it fails to change the global prognosis. We report a case of an unusual recovery of nonfluent chronic poststroke aphasia subsequent to extradural cortical stimulation. A right-handed woman experienced aphasia and drug-resistant central poststroke facial pain after a left superficial Sylvian ischemic stroke at the age of 58 years old. Four years after the stroke, the patient was included in a clinical trial to establish the efficiency of epidural electric stimulation on neuropathic pain. As an improvement in her language performance was noted, a speech evaluation was added to the initial protocol to quantify the benefit. Twelve months after the surgical implantation, pain and language performance were assessed in a double-blind manner during two consecutive 1-month periods when the stimulator was randomly enabled or disabled. The same evaluation was performed after 5 years of stimulation. Eventually, epidural electric stimulation significantly and sustainably improved her lexical access and speech fluency. Cortical stimulation may offer a new approach for the treatment of late chronic poststroke aphasia.

Acta Neurochirurgica, 2010

Tentorial dural arteriovenous fistulas are rare and complex lesions in deep locations with unusua... more Tentorial dural arteriovenous fistulas are rare and complex lesions in deep locations with unusual vascular anatomy and critical surrounding neuroanatomy. A rare case presenting a complex fistula with a giant venous draining ampulae, causing headaches and visual troubles is presented. We describe the case of a 52-year-old woman admitted in our department for headaches and visual troubles. Magnetic resonance imaging and cerebral angiography showed a tentorial dural arteriovenous fistula draining in a giant tentorial venous ampulae and leptomeningeal veins. The patient was embolised via an arterial route with a good clinical and radiological result. However, 4 days later she presented a sudden change of her clinical status with coma, left hemiparesis and a right midriasis. The cerebral computed tomography scan showed a huge occipital haemorrhagic mass and a severe cerebral oedema. An emergent surgical procedure was decided realising evacuation of the occipital haematoma and a complete resection of the giant venous ampoule. The neck of the ampulae was sutured and clipped at its dural entrance. Postoperatively a new embolisation was realised because of persistent of a small dural fistulae with occipital leptomeningeal drainage. The patient recovered rapidly with only a residual hemianopsy. Treatment of dural AV malformation represent a serious challenge. Our report describes an unusual case of a tentorial dural complex fistula treated by an endovascular procedure with secondary clinical aggravation that needed emergent surgical therapy. Even in a case for good immediate radiological result after endovascular procedure, dural arteriovenous fistulas with giant venous ampulae and important venous engorgement, need closed follow-up, because of the possibility of aggravation secondary to venous thrombosis and haemorrhage. Treatment and patophysiology of the aggravation mechanism are discussed.

Acta Neurochirurgica, 2010

Purpose Surgical treatment of cavernomas arising in the insula (especially in dominant cerebral h... more Purpose Surgical treatment of cavernomas arising in the insula (especially in dominant cerebral hemisphere) is challenging in reason of the proximity to the internal capsule and lenticulostriate arteries. The advent of image guidance systems and intraoperative mapping of the subcortical language pathways has broadened the surgical indications for these lesions. In this work, we report four cases of insular cavernomas operated on, and we define a surgical strategy for these lesions. Methods Between in our department, four patients harboring an insular cavernoma were operated on by using image guidance system (neuronavigation in three cases, ultrasound in one case). Subcortical stimulations were used to preserve the functional language area in one case. Findings The image guidance system determined the exact planning of the approach and determination of the ideal trajectory of insular cortex dissection. In a case of a deep left insular cavernoma, the shortest approach to remove the cavernoma was stopped in per-operative time because subcortical stimulation produced a speech inhibition, justifying another insular corticotomy. No surgical complications occurred, and the postoperative course was uneventful in all patients. Conclusion As it has been proposed by many authors, image guidance system is recommended in surgery of insular cavernomas. When the lesion is located in the dominant hemisphere, intraoperative mapping of the subcortical language pathways is also indicated to preserve the language functional areas.

PLoS ONE, 2013

Spinal cord injury (SCI) induces a permanent disability in patients. To this day no curative trea... more Spinal cord injury (SCI) induces a permanent disability in patients. To this day no curative treatment can be proposed to restore lost functions. Therefore, extensive experimental studies have been conducted to induce recovery after SCI. One of the most promising therapies is based on the use of olfactory ensheathing cells (OECs). OECs can be obtained from either the olfactory bulbs (OB-OECs) or from olfactory mucosa (OM-OECs), involving a less invasive approach for autotransplantation. However the vast majority of experimental transplantations have been focusing on OB-OECs although the OM represents a more accessible source of OECs. Importantly, the ability of OM-OECs in comparison to OB-OECs to induce spinal cord recovery in the same lesion paradigm has never been described. We here present data using a multiparametric approach, based on electrophysiological, behavioral, histological and magnetic resonance imaging experiments on the repair potential of OB-OECs and OM-OECs from either primary or purified cultures after a severe model of SCI. Our data demonstrate that transplantation of OECs obtained from OB or OM induces electrophysiological and functional recovery, reduces astrocyte reactivity and glial scar formation and improves axonal regrowth. We also show that the purification step is essential for OM-OECs while not required for OB-OECs. Altogether, our study strongly indicates that transplantation of OECs from OM represents the best benefit/risk ratio according to the safety of access of OM and the results induced by transplantations of OM-OECs. Indeed, purified OM-OECs in addition to induce recovery can integrate and survive up to 60 days into the spinal cord. Therefore, our results provide strong support for these cells as a viable therapy for SCI.