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Dive into the research topics where Sagi Harnof is active.

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Featured researches published by Sagi Harnof.


International Journal of Stroke | 2014

European Stroke Organisation (ESO) guidelines for the management of spontaneous intracerebral hemorrhage

Thorsten Steiner; Rustam Al-Shahi Salman; Ronnie Beer; Hanne Christensen; Charlotte Cordonnier; László Csiba; Michael Forsting; Sagi Harnof; Catharina J.M. Klijn; Derk Krieger; A. David Mendelow; Carlos A. Molina; Joan Montaner; Karsten Overgaard; Jesper Petersson; Risto O. Roine; Erich Schmutzhard; Karsten Schwerdtfeger; Christian Stapf; Turgut Tatlisumak; Brenda Thomas; Danilo Toni; Andreas Unterberg; Markus Wagner

Background Intracerebral hemorrhage (ICH) accounted for 9% to 27% of all strokes worldwide in the last decade, with high early case fatality and poor functional outcome. In view of recent randomized controlled trials (RCTs) of the management of ICH, the European Stroke Organisation (ESO) has updated its evidence-based guidelines for the management of ICH. Method A multidisciplinary writing committee of 24 researchers from 11 European countries identified 20 questions relating to ICH management and created recommendations based on the evidence in RCTs using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Results We found moderate- to high-quality evidence to support strong recommendations for managing patients with acute ICH on an acute stroke unit, avoiding hemostatic therapy for acute ICH not associated with antithrombotic drug use, avoiding graduated compression stockings, using intermittent pneumatic compression in immobile patients, and using blood pressure lowering for secondary prevention. We found moderate-quality evidence to support weak recommendations for intensive lowering of systolic blood pressure to <140 mmHg within six-hours of ICH onset, early surgery for patients with a Glasgow Coma Scale score 9–12, and avoidance of corticosteroids. Conclusion These guidelines inform the management of ICH based on evidence for the effects of treatments in RCTs. Outcome after ICH remains poor, prioritizing further RCTs of interventions to improve outcome.


Neurosurgery | 2006

Magnetic resonance imaging-guided, high-intensity focused ultrasound for brain tumor therapy

Zvi Ram; Zvi R. Cohen; Sagi Harnof; Sigal Tal; Meir Faibel; Dvora Nass; Stephan E. Maier; Moshe Hadani; Yael Mardor

OBJECTIVEMagnetic resonance imaging-guided high-intensity focused ultrasound (MRIgFUS) is a novel technique that may have the potential for precise image-guided thermocoagulation of intracranial lesions. The system delivers small volumetric sonications from an ultrasound phased array transmitter that focuses energy selectively to destroy the target with verification by magnetic resonance imaging-generated thermal maps. A Phase I clinical study was initiated to treat patients with recurrent glioma with MRIgFUS. METHODSTo date, three patients with histologically verified recurrent glioblastoma multiforme have been treated with MRIgFUS. All patients underwent craniectomy 7 to 10 days before therapy to create a bony window for the ultrasound treatment. Sonications were applied to induce thermocoagulation of the enhancing tumor mass. Long-term radiological follow-up and post-treatment tissue specimens were available for all patients. RESULTSMRIgFUS treatment resulted in immediate changes in contrast-enhanced T1-, T2-, and diffusion-weighted magnetic resonance imaging scans in the treated regions with subsequent histological evidence of thermocoagulation. In one patient, heating of brain tissue in the sonication path resulted in a secondary focus outside the target causing neurological deficit. New software modifications were developed to address this problem. CONCLUSIONIn this first clinical report, MRIgFUS was demonstrated to be a potentially effective means of destroying tumor tissue by thermocoagulation, although with an associated morbidity and the inherent invasive nature of the procedure requiring creation of a bone window. A modified technology to allow MRIgFUS treatment through a closed cranium is being developed.


The Lancet | 2017

Thrombolytic removal of intraventricular haemorrhage in treatment of severe stroke: results of the randomised, multicentre, multiregion, placebo-controlled CLEAR III trial

Daniel F. Hanley; Karen Lane; Nichol McBee; Wendy C. Ziai; Stanley Tuhrim; Kennedy R. Lees; Jesse Dawson; Dheeraj Gandhi; Natalie Ullman; W. Andrew Mould; Steven Mayo; A. David Mendelow; Barbara Gregson; Kenneth Butcher; Paul Vespa; David W. Wright; Carlos S. Kase; J. Ricardo Carhuapoma; Penelope M. Keyl; Marie Diener-West; John Muschelli; Joshua Betz; Carol B. Thompson; Elizabeth A. Sugar; Gayane Yenokyan; Scott Janis; Sayona John; Sagi Harnof; George A. Lopez; E. Francois Aldrich

BACKGROUND Intraventricular haemorrhage is a subtype of intracerebral haemorrhage, with 50% mortality and serious disability for survivors. We aimed to test whether attempting to remove intraventricular haemorrhage with alteplase versus saline irrigation improved functional outcome. METHODS In this randomised, double-blinded, placebo-controlled, multiregional trial (CLEAR III), participants with a routinely placed extraventricular drain, in the intensive care unit with stable, non-traumatic intracerebral haemorrhage volume less than 30 mL, intraventricular haemorrhage obstructing the 3rd or 4th ventricles, and no underlying pathology were adaptively randomly assigned (1:1), via a web-based system to receive up to 12 doses, 8 h apart of 1 mg of alteplase or 0·9% saline via the extraventricular drain. The treating physician, clinical research staff, and participants were masked to treatment assignment. CT scans were obtained every 24 h throughout dosing. The primary efficacy outcome was good functional outcome, defined as a modified Rankin Scale score (mRS) of 3 or less at 180 days per central adjudication by blinded evaluators. This study is registered with ClinicalTrials.gov, NCT00784134. FINDINGS Between Sept 18, 2009, and Jan 13, 2015, 500 patients were randomised: 249 to the alteplase group and 251 to the saline group. 180-day follow-up data were available for analysis from 246 of 249 participants in the alteplase group and 245 of 251 participants in the placebo group. The primary efficacy outcome was similar in each group (good outcome in alteplase group 48% vs saline 45%; risk ratio [RR] 1·06 [95% CI 0·88-1·28; p=0·554]). A difference of 3·5% (RR 1·08 [95% CI 0·90-1·29], p=0·420) was found after adjustment for intraventricular haemorrhage size and thalamic intracerebral haemorrhage. At 180 days, the treatment group had lower case fatality (46 [18%] vs saline 73 [29%], hazard ratio 0·60 [95% CI 0·41-0·86], p=0·006), but a greater proportion with mRS 5 (42 [17%] vs 21 [9%]; RR 1·99 [95% CI 1·22-3·26], p=0·007). Ventriculitis (17 [7%] alteplase vs 31 [12%] saline; RR 0·55 [95% CI 0·31-0·97], p=0·048) and serious adverse events (114 [46%] alteplase vs 151 [60%] saline; RR 0·76 [95% CI 0·64-0·90], p=0·002) were less frequent with alteplase treatment. Symptomatic bleeding (six [2%] in the alteplase group vs five [2%] in the saline group; RR 1·21 [95% CI 0·37-3·91], p=0·771) was similar. INTERPRETATION In patients with intraventricular haemorrhage and a routine extraventricular drain, irrigation with alteplase did not substantially improve functional outcomes at the mRS 3 cutoff compared with irrigation with saline. Protocol-based use of alteplase with extraventricular drain seems safe. Future investigation is needed to determine whether a greater frequency of complete intraventricular haemorrhage removal via alteplase produces gains in functional status. FUNDING National Institute of Neurological Disorders and Stroke.


Neurosurgery | 2007

Magnetic resonance imaging-guided focused ultrasound for thermal ablation in the brain: a feasibility study in a swine model.

Zvi R. Cohen; Jacob Zaubermann; Sagi Harnof; Yael Mardor; Dvora Nass; Eyal Zadicario; Arik Hananel; David Castel; Meir Faibel; Zvi Ram

INTRODUCTIONMagnetic resonance imaging (MRI)-guided focused ultrasound is a novel technique that was developed to enable precise, image-guided targeting and destruction of tumors by thermocoagulation. The system, ExAblate2000, is a focused ultrasound delivery system embedded within the MRI bed of a conventional diagnostic MRI scanner. The device delivers small volumetric sonications from an ultrasound phased array transmitter that converge energy to selectively destroy the target. Temperature maps generated by the MRI scanner verify the location and thermal rise as feedback, as well as thermal destruction. To assess the safety, feasibility, and precision of this technology in the brain, we have used the ExAblate system to create predefined thermal lesions in the brains of pigs. METHODSTen pigs underwent bilateral craniectomy to provide a bone window for the ultrasound beams. Seven to 10 days later, the animals were anesthetized and positioned in the ExAblate system. A predefined, 1-cm3 frontal para ventricular region was delineated as the target and treated with multiple sonications. MRI was performed immediately and 1 week after treatment. The animals were then sacrificed and the brains removed for pathological study. The size of individual sonication points and the location of the lesion were compared between the planned dose maps, posttreatment MRI scans, and pathological specimen. RESULTSHigh-energy sonications led to precise coagulation necrosis of the specified targets as shown by subsequent MRI, macroscopic, and histological analysis. The thermal lesions were sharply demarcated from the surrounding brain with no anatomic or histological abnormalities outside the target. CONCLUSIONMRI-guided focused ultrasound proved a precise and an effective means to destroy anatomically predefined brain targets by thermocoagulation with minimal associated edema or damage to adjacent structures. Contrast-enhanced T1-, T2-, and diffusion-weighted MRI scans may be used for real-time assessment of tissue destruction.


Journal of Neurosurgery | 2013

Minimally invasive treatment of intracerebral hemorrhage with magnetic resonance-guided focused ultrasound.

Stephen J. Monteith; Sagi Harnof; Ricky Medel; Britney Popp; Max Wintermark; M. Beatriz S. Lopes; Neal F. Kassell; W. Jeff Elias; John Snell; Matthew Eames; Eyal Zadicario; Krisztina Moldovan; Jason P. Sheehan

OBJECT Intracerebral hemorrhage (ICH) is a major cause of death and disability throughout the world. Surgical techniques are limited by their invasive nature and the associated disability caused during clot removal. Preliminary data have shown promise for the feasibility of transcranial MR-guided focused ultrasound (MRgFUS) sonothrombolysis in liquefying the clotted blood in ICH and thereby facilitating minimally invasive evacuation of the clot via a twist-drill craniostomy and aspiration tube. METHODS AND RESULTS In an in vitro model, the following optimum transcranial sonothrombolysis parameters were determined: transducer center frequency 230 kHz, power 3950 W, pulse repetition rate 1 kHz, duty cycle 10%, and sonication duration 30 seconds. Safety studies were performed in swine (n = 20). In a swine model of ICH, MRgFUS sonothrombolysis of 4 ml ICH was performed. Magnetic resonance imaging and histological examination demonstrated complete lysis of the ICH without additional brain injury, blood-brain barrier breakdown, or thermal necrosis due to sonothrombolysis. A novel cadaveric model of ICH was developed with 40-ml clots implanted into fresh cadaveric brains (n = 10). Intracerebral hemorrhages were successfully liquefied (> 95%) with transcranial MRgFUS in a highly accurate fashion, permitting minimally invasive aspiration of the lysate under MRI guidance. CONCLUSIONS The feasibility of transcranial MRgFUS sonothrombolysis was demonstrated in in vitro and cadaveric models of ICH. Initial in vivo safety data in a swine model of ICH suggest the process to be safe. Minimally invasive treatment of ICH with MRgFUS warrants evaluation in the setting of a clinical trial.


Cerebrovascular Diseases | 2011

European Research Priorities for Intracerebral Haemorrhage

Thorsten Steiner; Jesper Petersson; Rustam Al-Shahi Salman; Hanne Christensen; Charlotte Cordonnier; László Csiba; Sagi Harnof; Derk Krieger; David Mendelow; Carlos A. Molina; Joan Montaner; Karsten Overgaard; Risto O. Roine; Erich Schmutzhard; Turgut Tatlisumak; Danilo Toni; Christian Stapf

Over 2 million people are affected by intracerebral haemorrhage (ICH) worldwide every year, one third of them dying within 1 month, and many survivors being left with permanent disability. Unlike most other stroke types, the incidence, morbidity and mortality of ICH have not declined over time. No standardised diagnostic workup for the detection of the various underlying causes of ICH currently exists, and the evidence for medical or surgical therapeutic interventions remains limited. A dedicated European research programme for ICH is needed to identify ways to reduce the burden of ICH-related death and disability. The European Research Network on Intracerebral Haemorrhage EURONICH is a multidisciplinary academic research collaboration that has been established to define current research priorities and to conduct large clinical studies on all aspects of ICH.


Stroke | 2015

Accuracy of the ABC/2 Score for Intracerebral Hemorrhage: Systematic Review and Analysis of MISTIE, CLEAR-IVH, and CLEAR III

Alastair J.S. Webb; Natalie Ullman; Timothy C. Morgan; John Muschelli; Joshua Kornbluth; Issam A. Awad; Stephen Mayo; Michael Rosenblum; Wendy C. Ziai; Mario Zuccarrello; Francois Aldrich; Sayona John; Sagi Harnof; George A. Lopez; William C. Broaddus; Christine A.C. Wijman; Paul Vespa; Ross Bullock; Stephen J. Haines; Salvador Cruz-Flores; Stan Tuhrim; Michael D. Hill; Raj K. Narayan; Daniel F. Hanley

Background and Purpose— The ABC/2 score estimates intracerebral hemorrhage (ICH) volume, yet validations have been limited by small samples and inappropriate outcome measures. We determined accuracy of the ABC/2 score calculated at a specialized reading center (RC-ABC) or local site (site-ABC) versus the reference-standard computed tomography–based planimetry (CTP). Methods— In Minimally Invasive Surgery Plus Recombinant Tissue-Type Plasminogen Activator for Intracerebral Hemorrhage Evacuation-II (MISTIE-II), Clot Lysis Evaluation of Accelerated Resolution of Intraventricular Hemorrhage (CLEAR-IVH) and CLEAR-III trials. ICH volume was prospectively calculated by CTP, RC-ABC, and site-ABC. Agreement between CTP and ABC/2 was defined as an absolute difference up to 5 mL and relative difference within 20%. Determinants of ABC/2 accuracy were assessed by logistic regression. Results— In 4369 scans from 507 patients, CTP was more strongly correlated with RC-ABC (r2=0.93) than with site-ABC (r2=0.87). Although RC-ABC overestimated CTP-based volume on average (RC-ABC, 15.2 cm3; CTP, 12.7 cm3), agreement was reasonable when categorized into mild, moderate, and severe ICH (&kgr;=0.75; P<0.001). This was consistent with overestimation of ICH volume in 6 of 8 previous studies. Agreement with CTP was greater for RC-ABC (84% within 5 mL; 48% of scans within 20%) than for site-ABC (81% within 5 mL; 41% within 20%). RC-ABC had moderate accuracy for detecting ≥5 mL change in CTP volume between consecutive scans (sensitivity, 0.76; specificity, 0.86) and was more accurate with smaller ICH, thalamic hemorrhage, and homogeneous clots. Conclusions— ABC/2 scores at local or central sites are sufficiently accurate to categorize ICH volume and assess eligibility for the CLEAR-III and MISTIE III studies and moderately accurate for change in ICH volume. However, accuracy decreases with large, irregular, or lobar clots. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: MISTIE-II NCT00224770; CLEAR-III NCT00784134.


Journal of Clinical Neuroscience | 2014

Modulation of mind: therapeutic neuromodulation for cognitive disability

Zion Zibly; Andrew Shaw; Sagi Harnof; Mayur Sharma; Christian Graves; Milind Deogaonkar; Ali R. Rezai

Neuromodulation using deep brain stimulation (DBS) has become an established therapy for the treatment of certain disorders such as Parkinsons disease and tremors. Recent advances in surgical and imaging techniques further decrease the surgical risk associated with these procedures. Symptoms such as tremor, bradykinesia, rigidity and gait disturbances can be significantly controlled with DBS. This results in an opportunity to decrease anti-parkinsonism medications, and their dyskinetic side-effects. Following the success of DBS in the management of movement disorders, the role of this therapy is being extensively studied in more complex disorders that involve cognition and behavior. The inherent complexity in cognitive circuitry makes neuromodulation using DBS more difficult than in movement disorders. The goal of DBS surgery in these diseases is not only to slow the cognitive decline, but also restoration of function and ultimately improvement in the quality of life. DBS as a treatment for patients with advanced dementia holds significant promise in delaying or reversing the progressive cognitive decline by enhancing connectivity in the memory networks. In appropriately selected patients this potentially reversible surgical therapy can lead to a significant improvement in the quality of life and reduce the burden on patients, families and the healthcare system. This review focuses on the recent and future studies involving neuromodulation for cognitive disorders such as Alzheimers disease and Huntingtons disease.


Neurosurgical Focus | 2013

Transcranial MR-guided focused ultrasound sonothrombolysis in the treatment of intracerebral hemorrhage

Stephen J. Monteith; Neal F. Kassell; Oded Goren; Sagi Harnof

Intracerebral hemorrhage remains a significant cause of morbidity and mortality. Current surgical therapies aim to use a minimally invasive approach to remove as much of the clot as possible without causing undue disruption to surrounding neural structures. Transcranial MR-guided focused ultrasound (MRgFUS) surgery is an emerging technology that permits a highly concentrated focal point of ultrasound energy to be deposited to a target deep within the brain without an incision or craniotomy. With appropriate ultrasound parameters it has been shown that MRgFUS can effectively liquefy large-volume blood clots through the human calvaria. In this review the authors discuss the rationale for using MRgFUS to noninvasively liquefy intracerebral hemorrhage (ICH), thereby permitting minimally invasive aspiration of the liquefied clot via a small drainage tube. The mechanism of action of MRgFUS sonothrombolysis; current investigational work with in vitro, in vivo, and cadaveric models of ICH; and the potential clinical application of this disruptive technology for the treatment of ICH are discussed.


Journal of Clinical Neuroscience | 2015

Spontaneous spinal epidural hematoma: The importance of preoperative neurological status and rapid intervention

Gustavo Rajz; José E. Cohen; Sagi Harnof; Nachshon Knoller; Oded Goren; Yigal Shoshan; Shifra Fraifeld; Leon Kaplan; Eyal Itshayek

We describe the presentation, management, and outcome of spontaneous spinal epidural hematoma (SSEH) in two tertiary academic centers. We retrospectively reviewed clinical and imaging files in patients diagnosed with SSEH from 2002-2011. Neurologic status was assessed using the American Spinal Injury Association (ASIA) Impairment Scale (AIS). A total of 17 patients (10 females; mean age 54 years, range 10-89) were included. Among patients presenting with AIS A, 5/8 showed no improvement and 3/8 reached AIS C. Among those presenting with AIS C, 5/6 reached AIS E and 1/6 reached AIS D. Of those presenting with AIS D, 3/3 reached AIS E. Mean time-to-surgery (TTS) was 28 hours (range 3-96). TTS surgery in two patients remaining at AIS A was ⩽ 12 hours; in 4/8 patients recovering to AIS E it was > 12 hours, including three patients operated on after > 24 hours. In patients remaining at AIS A, a mean of 4.4 levels were treated compared with means of 3.7 and 3.5 in those with AIS C and E, respectively, at late follow-up. In this series, preoperative neurological status had greater impact on late outcome than time from symptom onset to surgery in patients with SSEH.

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