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Dive into the research topics where Isabelle F. Klein is active.

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Featured researches published by Isabelle F. Klein.


Lancet Neurology | 2007

A transient ischaemic attack clinic with round-the-clock access (SOS-TIA): feasibility and effects

Philippa C. Lavallée; Elena Meseguer; Halim Abboud; Lucie Cabrejo; Jean-Marc Olivot; Olivier Simon; Mikael Mazighi; Chantal Nifle; Philippe Niclot; Bertrand Lapergue; Isabelle F. Klein; Eric Brochet; Philippe Gabriel Steg; Guy Lesèche; Julien Labreuche; Pierre-Jean Touboul; Pierre Amarenco

BACKGROUND Diagnosis and treatment of cerebral and retinal transient ischaemic attacks (TIAs) are often delayed by the lack of immediate access to a dedicated TIA clinic. We evaluated the effects of rapid assessment of patients with TIA on clinical decision making, length of hospital stay, and subsequent stroke rates. METHODS We set up SOS-TIA, a hospital clinic with 24-h access. Patients were admitted if they had sudden retinal or cerebral focal symptoms judged to relate to ischaemia and if they made a total recovery. Assessment, which included neurological, arterial, and cardiac imaging, was within 4 h of admission. A leaflet about TIA with a toll-free telephone number for SOS-TIA was sent to 15 000 family doctors, cardiologists, neurologists, and ophthalmologists in Paris and its administrative region. Endpoints were stroke within 90 days, and stroke, myocardial infarction, and vascular death within 1 year. FINDINGS Between January, 2003, and December, 2005, we admitted 1085 patients with suspected TIA; 574 (53%) were seen within 24 h of symptom onset. 701 (65%) patients had confirmed TIA or minor stroke, and 144 (13%) had possible TIA. 108 (17%) of the 643 patients with confirmed TIA had brain tissue damage. Median duration of symptoms was 15 min (IQR 5-75 min). Of the patients with confirmed or possible TIA, all started a stroke prevention programme, 43 (5%) had urgent carotid revascularisation, and 44 (5%) were treated for atrial fibrillation with anticoagulants. 808 (74%) of all patients seen were sent home on the same day. The 90-day stroke rate was 1.24% (95% CI 0.72-2.12), whereas the rate predicted from ABCD(2) scores was 5.96%. INTERPRETATION Use of TIA clinics with 24-h access and immediate initiation of preventive treatment might greatly reduce length of hospital stay and risk of stroke compared with expected risk.


Lancet Neurology | 2009

Comparison of intravenous alteplase with a combined intravenous–endovascular approach in patients with stroke and confirmed arterial occlusion (RECANALISE study): a prospective cohort study

Mikael Mazighi; Jean-Michel Serfaty; Julien Labreuche; Jean-Pierre Laissy; Elena Meseguer; Philippa C. Lavallée; Lucie Cabrejo; Tarik Slaoui; Céline Guidoux; Bertrand Lapergue; Isabelle F. Klein; Jean-Marc Olivot; Gai Raphaeli; Christiane Gohin; Elisabeth Schouman Claeys; Pierre Amarenco

BACKGROUND The efficacy of intravenous (IV) alteplase is restricted by the speed of recanalisation and the site of the occlusion. The aim of this study was to ascertain the effect of a combined IV-endovascular approach (intra-arterial alteplase and, if required, additional thrombectomy) in patients with stroke due to arterial occlusion. METHODS We compared recanalisation rates, neurological improvement at 24 h, and functional outcome at 3 months between two periods (February, 2002, to March, 2007, vs April, 2007, to October, 2008) in patients in a prospective registry who were treated with different regimens of alteplase within 3 h of symptom onset. Patients with confirmed occlusion who were treated before April, 2007, were treated with IV alteplase; after April, 2007, patients were treated with a systematic IV-endovascular approach. Analysis was by intention to treat. FINDINGS 46 (87%) of 53 patients treated with the IV-endovascular approach achieved recanalisation versus 56 (52%) of 107 patients in the IV group (adjusted relative risk [RR] 1.49, 95% CI 1.21-1.84; p=0.0002). Early neurological improvement (NIHSS score of 0 or 1 or an improvement of 4 points or more at 24 h) occurred in 32 (60%) patients in the IV-endovascular group and 42 (39%) patients in the IV group (adjusted RR 1.36, 0.97-1.91; p=0.07). Favourable outcome (mRS of 0-2 at 90 days) occurred in 30 (57%) patients in the IV-endovascular group and 47 (44%) patients in the IV group (adjusted RR 1.16, 0.85-1.58; p=0.35). The mortality rate at 90 days was 17% in both groups, and symptomatic intracranial haemorrhage was reported in five (9%) patients in the IV-endovascular group and in 12 (11%) patients in the IV group. Better clinical outcome was associated with recanalisation in both groups and with time to recanalisation in the IV-endovascular group. INTERPRETATION An IV-endovascular approach is associated with higher recanalisation rates than is IV alteplase in patients with stroke and confirmed arterial occlusion. In patients treated with an IV-endovascular approach, a shorter time from symptom onset to recanalisation is associated with better clinical outcomes.


Stroke | 2007

Stent-Assisted Endovascular Thrombolysis Versus Intravenous Thrombolysis in Internal Carotid Artery Dissection With Tandem Internal Carotid and Middle Cerebral Artery Occlusion

Philippa C. Lavallée; Mickaël Mazighi; Jean-Pierre Saint-Maurice; Elena Meseguer; Halim Abboud; Isabelle F. Klein; Emmanuel Houdart; Pierre Amarenco

Background and Purpose— Tandem internal carotid and middle cerebral artery occlusion independently predicts poor outcome after intravenous thrombolysis. Recanalization of internal carotid artery dissection by stent-assisted angioplasty has recently been proposed when anticoagulation fails to prevent a new ischemic event. We recently reported a case of tandem internal carotid and middle cerebral artery occlusion with dissection of the internal carotid artery successfully treated with endovascular stent-assisted thrombolysis. Methods— We compared clinical outcomes in consecutive patients presenting with tandem internal carotid and middle cerebral artery occlusion with internal carotid artery dissection within 3 hours of symptom onset who were eligible for intravenous thrombolysis, treated by either endovascular stent-assisted thrombolysis or intravenous recombinant tissue-type plasminogen activator (rtPA) when an endovascular therapist was unavailable. National Institutes of Health Stroke Scale scores were obtained at baseline and after 24 hours. The modified Rankin Scale score was used to assess outcomes at 3 months. Arterial recanalization was assessed by magnetic resonance imaging. Results— Of 10 patients screened, 6 were treated with endovascular therapy and 4 with intravenous rtPA. Before treatment, mean National Institutes of Health Stroke Scale scores were high and comparable in the 2 groups (17 and 16, respectively). In the endovascular group, all patients achieved middle cerebral artery recanalization with subsequent dramatic improvement versus only 1 patient with middle cerebral artery recanalization in the intravenous rtPA group. At 3 months, 4 patients in the endovascular group had a favorable outcome (modified Rankin Scale score=0). In the intravenous rtPA group, 3 patients had a poor outcome (modified Rankin Scale score≥3). Conclusions— Endovascular stent-assisted thrombolysis is a promising treatment in tandem internal carotid and middle cerebral artery occlusion due to internal carotid artery dissection and compares favorably with intravenous rtPA.


Stroke | 2010

Basilar Artery Atherosclerotic Plaques in Paramedian and Lacunar Pontine Infarctions A High-Resolution MRI Study

Isabelle F. Klein; Philippa C. Lavallée; Mikael Mazighi; Elisabeth Schouman-Claeys; Julien Labreuche; Pierre Amarenco

Background and Purpose— Pontine infarction is most often related to basilar artery atherosclerosis when the lesion abuts on the basal surface (paramedian pontine infarction), whereas small medial pontine lesion is usually attributed to small vessel lipohyalinosis. A previous study has found that high-resolution MRI can detect basilar atherosclerotic plaques in up to 70% of patient with paramedian pontine infarction, even in patients with normal angiograms, but none has evaluated the presence of basilar artery plaque by high-resolution MRI in patients with small medial pontine lesion in the medial part of the pons. Methods— Consecutive patients with pontine infarction underwent basilar angiography using time-of-flight and contrast-enhanced 3-dimensional MR angiography to assess the presence of basilar artery stenosis and high-resolution MRI to assess the presence of atherosclerotic plaque. Basilar artery angiogram was scored as “normal,” “irregular,” or “stenosed” ≥30%” and basilar artery by high-resolution MRI was scored as “normal” or “presence of plaque.” Medial pontine infarcts were divided into paramedian pontine infarction and small medial pontine lesion groups. Results— Forty-one patients with pontine infarction were included, 26 with paramedian pontine infarction and 15 with small medial pontine lesion. High-resolution MRI detected basilar artery atherosclerosis in 42% of patients with a pontine infarction and normal basilar angiograms. Among patients with paramedian pontine infarction, 65% had normal basilar angiograms but 77% had basilar artery atherosclerosis detected on high-resolution MRI. Among patients with small medial pontine lesion, 46% had normal basilar angiograms but 73% had basilar artery plaques detected on by high-resolution MRI. Conclusions— This study suggests that medial pontine lacunes may be due to a penetrating artery disease secondary to basilar artery atherosclerosis. High-resolution MRI could help precise stroke subtyping.


Stroke | 2011

Prevalence of Coronary Atherosclerosis in Patients With Cerebral Infarction

Pierre Amarenco; Philippa C. Lavallée; Julien Labreuche; Gregory Ducrocq; Jean-Michel Juliard; Laurent J. Feldman; Lucie Cabrejo; Elena Meseguer; Céline Guidoux; Valérie Adraï; Samina Ratani; Jérôme Kusmierek; Bertrand Lapergue; Isabelle F. Klein; Fernando Góngora-Rivera; Arturo Jaramillo; Mikael Mazighi; Pierre-Jean Touboul; Philippe Gabriel Steg

Background and Purpose— There is an overlap between stroke and coronary heart disease, but the exact prevalence of coronary artery disease in patients with nonfatal cerebral infarction is unclear, particularly when there is no known history of coronary heart disease. Methods— We consecutively enrolled 405 patients presenting with acute cerebral infarction documented by neuroimaging who underwent carotid and femoral artery, thoracic, and abdominal aorta ultrasound examinations. Of the 342 patients with no known coronary heart disease, 315 underwent coronary angiography a median of 8 days (interquartile range, 6–11) after stroke onset. Results— Coronary plaques on angiography, regardless of stenosis severity, were present in 61.9% of patients (95% confidence interval [CI], 56.5–67.3) and coronary stenoses ≥50% were found in 25.7% (95% CI, 20.9–30.5). The overall prevalence of coronary plaque increased with the number of arterial territories (carotid or femoral arteries) involved, with an adjusted odds ratio of coronary artery disease of 1.25 (95% CI, 0.58–2.71) for presence of plaque in 1 territory, and 4.31 (95% CI, 1.92–9.68) for presence of plaque in both territories, compared with no plaque in either territory. The presence of plaque in both femoral and carotid arteries had an age- and sex-adjusted positive predictive value of 84% for presence of coronary plaque and a negative predictive value of 44%. Conclusions— There is a high burden of silent coronary artery disease in patients with nonfatal cerebral infarction and no known coronary heart disease, even in the absence of systemic atherosclerosis. The prevalence is even higher in patients with evidence of carotid and/or femoral plaque.


Neurology | 2006

In vivo middle cerebral artery plaque imaging by high-resolution MRI

Isabelle F. Klein; Philippa C. Lavallée; Pierre-Jean Touboul; Elisabeth Schouman-Claeys; Pierre Amarenco

Middle cerebral artery (MCA) atherosclerosis is currently diagnosed by indirect angiographic methods. The authors used high-resolution MRI (HR-MRI) to study MCA stenosis in six patients. At the level of stenosis, an MCA plaque was clearly delineated and significantly measured vs nonatherosclerotic MCA segments, showing that HR-MRI is an accurate direct imaging method.


Neurology | 2005

High-resolution MRI identifies basilar artery plaques in paramedian pontine infarct

Isabelle F. Klein; Philippa C. Lavallée; Elisabeth Schouman-Claeys; Pierre Amarenco

Paramedian pontine infarct (PPI) is usually attributed to basilar artery (BA) atherosclerosis. However, this hypothesis has thus far been supported only by post-mortem studies. The authors show that high-resolution MRI is a promising method that can detect BA plaques in patients with PPI at or near the origin of the penetrating artery, whereas MR angiograms may appear normal.


Stroke | 2009

Cerebral microbleeds are frequent in infective endocarditis: a case-control study.

Isabelle F. Klein; Bernard Iung; Julien Labreuche; Agathe Hess; Michel Wolff; David Messika-Zeitoun; Philippa C. Lavallée; Jean-Pierre Laissy; Catherine Leport; Xavier Duval

Background and Purpose— Cerebral microbleeds (CMBs) have been described using MRI in patients with cardiovascular risk factors or prior stroke and could be an indicator of small vessel disease. CMBs have been reported in isolated cases of infective endocarditis (IE), but their frequency and the association of CMBs with IE have not yet been studied. Methods— A case–control imaging study in a referral institutional tertiary care center was conducted. Systematic brain MRIs, including T2*-weighted sequences, were performed in 60 patients with IE within 7 days of hospital admission and in 120 age- and gender-matched control subjects without IE. Two neuroradiologists, who were blinded to patient characteristics, independently assessed the presence, location, and size of CMBs using a standardized form. Results— The interobserver agreement level on the presence of CMBs was high with a &kgr; coefficient range (95% CI) of 0.70 (0.42 to 0.98) for subcortical regions to 0.91 (0.82 to 0.99) for cortical areas. CMBs were more prevalent in patients with IE (57% [n=34]) than in control subjects (15% [n=18]; matched OR, 10.06; 95% CI, 3.88 to 26.07). Moreover, the OR of IE increased gradually with CMBs number with an OR of 6.12 (95% CI, 2.09 to 17.94) for one to 3 CMBs and of 20.12 (95% CI, 5.20 to 77.80) for >3 CMBs. Conclusion— CMBs are highly frequent in patients with IE. The strong association found between IE and CMBs supports the need for further evaluation of CMBs as additional diagnostic criteria of IE.


Medicine | 2007

Long-term outcome in Susac syndrome.

Fleur Aubart-Cohen; Isabelle F. Klein; Jean-François Alexandra; Bahram Bodaghi; Serge Doan; Christine Fardeau; Philippa C. Lavallée; Jean-Charles Piette; Phuc Le Hoang; Thomas Papo

Susac syndrome is characterized by the clinical triad of encephalopathy, hearing loss, and retinal artery branch occlusions, mostly in young women. To our knowledge, long-term outcome and impact of pregnancy have not been specifically addressed. We report a series of 9 patients (7 female, 2 male) followed at the same institution, with special emphasis on clinical outcome including pregnancy and long-term sequelae. Clinical, brain magnetic resonance imaging (MRI), funduscopy, retinal angiography, and audiogram data were recorded every 3-12 months. We also analyzed the 92 previously reported cases of Susac syndrome. Mean follow-up was 6.4 years. Age at onset was 30.4 years. The first symptom occurred between April and September in 7 of 9 patients in the current study, and in 68% of all patients. The complete triad at onset was clinically obvious in only 1 of 9 patients. Brain involvement was heralded by headache and symptoms of encephalopathy. Cerebrospinal fluid was abnormal in 5 patients showing pleocytosis (mean, 24.6; range, 6-85 cells/mL) and elevated protein level (mean, 210; range, 113-365 mg/dL). Over time, quantitative brain MRI analysis showed that the number of lesions diminished and did not parallel clinical flares, and MRI never normalized. At the end of follow-up, no patient had severe impairment, and all but 1 returned to work. Inner ear involvement was present at onset in 2 patients and occurred in others with a mean delay of 11 months. Initially unilateral in 3, it became bilateral in all. Mean hearing loss was 34 dB (range, 15-70 dB). Hearing loss never improved, either spontaneously or under treatment. The eye was involved at onset in 8 patients, and after 3 years in 1. All had multiple bilateral retinal artery branch occlusions and/or dye leakage with hyperfluorescence of the arterial wall on fluorescein angiography. Over time, angiography normalized in 3 patients. In others, it was still abnormal at the end of follow-up (range, 1.5-10 yr). On late findings, fluorescein leakage was more frequent than true arterial occlusion. Eye involvement was mostly asymptomatic, unilateral, peripheral, and resumed spontaneously to remit in other sites over time. Corticosteroids were efficient to treat encephalopathy, with relapses occurring when the dosage was tapered. Steroid treatment did not improve hearing loss or prevent new retinal arteriolar occlusions. Anticoagulation had a role in treating encephalopathy and retinal arteriolar occlusions. Three patients had 4 pregnancies. Two pregnancies needed induced abortion. One pregnancy was uneventful. One pregnancy was complicated with Susac disease flare in the early postpartum period. In conclusion, at the end of follow-up, most patients had returned to work and none had severe impairment. Pregnancy may affect the course of Susac syndrome, with relapse of encephalopathy postpartum. Our main finding was that the course of Susac syndrome is not self-limited as previously thought, since isolated retinal arteriolar involvement may occur as a very late manifestation. Abbreviations: CSF = cerebrospinal fluid, FLAIR = fluid-attenuated inversion recovery, MRI = magnetic resonance imaging.


Journal of Infection | 2009

Post-infectious encephalitis in adults: Diagnosis and management

Romain Sonneville; Isabelle F. Klein; T. de Broucker; Michel Wolff

Summary Many important central nervous system (CNS) syndromes can develop following microbial infections. The most severe forms of post-infectious encephalitis include acute disseminated encephalomyelitis (ADEM), acute hemorrhagic leukoencephalitis and Bickerstaffs brainstem encephalitis. ADEM is an inflammatory demyelinating disorder of the CNS. It typically follows a minor infection with a 2–30 days latency period and is thought to be immune-mediated. It is clinically characterized by the acute onset of focal neurological signs and encephalopathy. Patients can require intensive care unit admission because of coma, seizures or tetraplegia. Cerebrospinal fluid analysis usually shows lymphocytic pleocytosis but, unlike viral or bacterial encephalitis, no evidence of direct CNS infection is found. There are no biologic markers of the disease and cerebral magnetic resonance imaging is essential to diagnosis, detecting diffuse or multifocal asymmetrical lesions throughout the white matter on T2- and FLAIR-weighted sequences. High-dose intravenous steroids are accepted as first-line therapy and beneficial effects of plasma exchanges and intravenous immunoglobulins have also been reported. Outcome of ADEM is usually favorable but recurrent or multiphasic forms have been described.

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Fernando Góngora-Rivera

Universidad Autónoma de Nuevo León

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Olivier Lidove

Necker-Enfants Malades Hospital

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