Lee R. Guterman

State University of New York, New York City, New York, United States

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Publications (183)545.65 Total impact

  • Neurosurgery 11/2010; 67(5):1442-1443. · 3.62 Impact Factor
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    ABSTRACT: The external carotid artery (ECA) anastomoses in many distal territories supplied by the internal carotid artery (ICA) and is an important source of collateral circulation to the brain. Stenosis of the ECA in ipsilateral ICA occlusion can produce ischemic sequelae. To examine the effectiveness of ECA stenting in treating symptomatic ipsilateral ICA occlusion. We retrospectively reviewed patient databases from 5 academic medical centers to identify all individuals who underwent ECA stenting after 1998. For all discovered cases, coinvestigators used a common submission form to harvest relevant demographic information, clinical data, procedural details, and follow-up results for further analysis. Twelve patients (median age, 66 years; range, 45-79 years) were identified for our cohort. Vessel disease involvement included severe ECA stenosis >or= 70% in 11 patients and ipsilateral ICA occlusion in all patients. Presenting symptoms included signs of transient ischemic attack, stroke, and amaurosis fugax. ECA stenting was associated with preservation of neurological status in 11 patients and resolution of symptoms in 5 patients at a median follow-up time of 26 months (range, 1-87 months; mean, 29 months). Symptomatic in-stent restenosis did not occur within any patient during the follow-up course. We found ECA stenting in symptomatic ipsilateral ICA disease to be a potentially effective strategy to preserve neurological function and to relieve ischemic symptoms. Further investigation with larger studies and longer follow-up periods is warranted to elucidate the true indications of this management strategy.
    Neurosurgery 08/2010; 67(2):314-21. DOI:10.1227/01.NEU.0000371728.49216.3B · 3.62 Impact Factor
  • Circulation 01/2009; 118(25):2845-51. DOI:10.1161/CIRCULATIONAHA.108.191174 · 14.43 Impact Factor
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    ABSTRACT: Currently, there is minimal published data on the use of heparin-coated stents in the neurovasculature; however, these stents have a proven clinical record in the treatment of coronary disease. This article details our experience with the safety and technical aspects of stent deployment in the first 10 patients who had heparin-coated stents placed in the intracranial and cervical vasculature and the preliminary follow-up in most cases. We retrospectively reviewed the clinical history, intra- and periprocedural data, and imaging for the patients who received heparin-coated stents in the cervical and intracranial vasculature for cerebrovascular disease between October 2002 and October 2003. Thirteen heparin-coated stents were placed in 10 patients. Seven out of the 10 patients had heparin-coated stents placed in the posterior circulation; the remaining three patients had stents placed in the anterior circulation. Four patients had stents placed intracranially. There was no acute or subacute in-stent thrombosis and no procedure-related complications. Follow-up was performed on most patients, with no clinical symptoms attributable to restenosis in any patient. This small series suggests that heparin-coated stents are safe for use in the treatment of cervical and intracranial atherosclerotic disease. Longer-term follow-up is needed to study the heparin coating effect on in-stent restenosis rates and to assess the long-term durability and clinical efficacy of this stent. The use of drug-coated stents in the cerebrovascular circulation is an area that warrants further investigation.
    Neurosurgery 11/2006; 59(4):812-21; discussion 821. DOI:10.1227/01.NEU.0000232836.66310.46 · 3.62 Impact Factor
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    ABSTRACT: We describe the case of an 82-year-old man with a fixed neurological deficit of 30 h duration. A left hemispheric perfusion deficit was found on perfusion/diffusion imaging studies in conjunction with an ipsilateral carotid stenosis documented by cerebral angiography. Carotid angioplasty with stent placement was performed and resulted in dramatic clinical improvement. Carotid stenosis can cause acute hemodynamic hypoperfusion with a symptomatic reversible clinical deficit.
    Neuroradiology 05/2006; 48(4):259-63. DOI:10.1007/s00234-005-0036-1 · 2.49 Impact Factor
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    ABSTRACT: To describe a novel application of the Neuroform stent (Boston Scientific-Target, Fremont, CA) for the management of eight wide-necked aneurysms. All patients were treated using a single Neuroform stent placed partially into the aneurysm and into the afferent artery. The portion of the stent protruding into the aneurysm fundus provided neck support for the subsequent successful coiling. The Neuroform stent is a versatile device that can be used in a variety of ways to assist in the coiling of wide-necked aneurysms. The technique described here may be used for bifurcation aneurysms in lieu of using two stents in a Y configuration.
    Neurosurgery 05/2006; 58(4 Suppl 2):ONS-258-62; discussion ONS-262. DOI:10.1227/01.NEU.0000204713.24945.D2 · 3.62 Impact Factor
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    ABSTRACT: In patients who are not candidates for intravenous tissue plasminogen activator, intra-arterial (IA) therapy is an alternative. Current recanalization rates are 50 to 60% for IA thrombolysis. Stent-assisted recanalization in the setting of acute stroke after failed thrombolysis may improve recanalization rates. A retrospective analysis was performed of 19 patients treated at two institutions between July 2001 and March, 2005 with intracranial stenting of a vessel resistant to standard thrombolytic techniques. Demographics, clinical, and radiographic presentation and outcomes were studied. Thirteen men and six women with a median baseline National Institutes of Health Stroke Scale (NIHSS) score of 16 (range, 15-22) were included. Eight lesions were located at the internal carotid artery terminus, seven in the M1/M2 segment, and four in the basilar artery. Average time-to-treatment was 210 +/- 160 minutes. Overall recanalization rate (Thrombolysis in Cerebral Infarction Grade 2 or 3) was 79%. There were six deaths: five due to progression of stroke and withdrawal of care at the family's request and one as the result of a delayed carotid injury after tracheostomy. One postoperative asymptomatic intracranial hemorrhage occurred without adverse affect on outcome. Median discharge NIHSS score of surviving patients was 5 (range, 2.5-11.5). Lesions at the internal carotid artery terminus (P < 0.009), older age (P < 0.003), and higher baseline NIHSS score (P < 0.009) were significant negative outcome predictors, as measured by >3 modified Rankin scale score at discharge. Stent-assisted recanalization for acute stroke resulting from intracranial thrombotic occlusion is associated with a high recanalization rate and low intracranial hemorrhage rate. These initial results suggest that stenting may be an option for recalcitrant cerebral arterial occlusions.
    Neurosurgery 04/2006; 58(3):458-63; discussion 458-63. DOI:10.1227/01.NEU.0000199159.32210.E4 · 3.62 Impact Factor
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    ABSTRACT: Acute ischemic stroke is the third leading cause of death in the United States. For patients with NIHSS scores >10 and evaluated within 6 hours, intra-arterial thrombolysis is the treatment of choice. The Merci retriever (Concentric Medical Inc., Mountain View, CA) and IV TPA are currently the only FDA-approved treatments for acute ischemic stroke. For patients who do not meet the criteria for TPA administration and/or in whom the Merci device fails, options are limited. Intracranial stenting for acute ischemic stroke after failed thrombolysis is now possible because of improved delivery systems and appropriately sized stents. A 26-year-old woman presented with an NIHSS score of 11 (right-sided hemiparesis and mixed aphasia) 4 hours from the time of symptom onset. CT perfusion demonstrated increased time to peak in the entire left hemisphere; conventional angiography demonstrated a left M1 occlusion. After crossing the occlusion with a microcatheter, reteplase (2 units) was administered into the clot. Mechanical thrombolysis was then attempted, without restoration of flow. Two 3 x 12-mm coronary stents were placed from the M1 into the superior and inferior divisions, respectively, with complete restoration of flow (TIMI 3). Within 72 hours, the patient had an NIHSS score of 1, with a small infarction in the external capsule. Novel stroke interventions need to be developed for patients with acute ischemic stroke in whom traditional interventions fail. We present (to our knowledge) the first case of successful revascularization of an acute M1 occlusion accomplished with placement of two coronary stents.
    Neurosurgery 04/2006; 58(3):E588; discussion E588. DOI:10.1227/01.NEU.0000197522.11613.0C · 3.62 Impact Factor
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    ABSTRACT: Patients 80 years and older are generally considered to be at an increased risk for stroke and death from carotid endarterectomy. High-risk status often qualifies them for entry into a carotid angioplasty and stenting (CAS) trial. The aim of this study is to report periprocedure (0-30 d) morbidity and mortality among elderly patients undergoing CAS with and without distal embolic protection in an intention-to-treat analysis. A retrospective review was performed to evaluate the medical records and imaging studies of patients 80 years or older who underwent attempted CAS procedures with and without distal embolic protection between June 1996 and February 2004. Ages of the 75 patients identified in our review ranged from 80 to 91 years (average 83.1 yr); 41 were men. Internal carotid artery stenosis ranged from 60 to 95% (mean 78.3%). Forty-two patients had symptoms (transient ischemic attack, 29; stroke, 13), and 33 patients were asymptomatic. Total event rates were major stroke, 4% (3 patients); minor stroke, 6.7% (5 patients); death, 4% (3 patients). Rates in the unprotected group (35 patients) were major stroke, 8.6% (3 patients); minor stroke, 5.7% (2 patients); major stroke/death, 14.3% (5 patients). Rates in the protected group (40 patients) were major stroke, 0; minor stroke, 7.5% (3 patients); major stroke/death, 0; (P < 0.05). These results suggest that elderly patients undergoing CAS with adjunctive distal embolic protection are at a lower risk of periprocedure adverse events. Routine clopidogrel use, smaller hardware profile, patient selection, and increased experience likely contributed to these results.
    Neurosurgery 03/2006; 58(2):233-40; discussion 233-40. DOI:10.1227/01.NEU.0000194832.96470.CD · 3.62 Impact Factor
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    ABSTRACT: We performed a preliminary feasibility and safety study using intravenous (IV) administration of a platelet glycoprotein IIb/IIIa inhibitor (abciximab) in conjunction with intraarterial (IA) administration of a thrombolytic agent (reteplase) in a primate model of intracranial thrombosis. We introduced thrombus through superselective catheterization of the intracranial segment of the internal carotid artery in 16 primates. The animals were randomly assigned to receive IA reteplase and IV abciximab ( n =4), IA reteplase and IV placebo ( n =4), IA placebo and IV abciximab ( n =4) or IA and IV placebo ( n =4). Recanalization was assessed by serial angiography during the 6-h period after initiation of treatment. Postmortem magnetic resonance (MR) imaging was performed to determine the presence of cerebral infarction or intracranial hemorrhage. Partial or complete recanalization at 6 h after initiation of treatment (decrease of two or more points in pre-treatment angiographic occlusion grade) was observed in two animals treated with IA reteplase and IV abciximab, three animals treated with IA reteplase alone and one animal treated with IV abciximab alone. No improvement in perfusion was observed in animals that received IV and IA placebo. Cerebral infarction was demonstrated on postmortem MR imaging in three animals that received IA and IV placebo and in one animal each from the groups that received IA reteplase and IV abciximab or IV abciximab alone. One animal that received IV abciximab alone had a small intracerebral hemorrhage on MR imaging. IA reteplase with or without abciximab appeared to be the most effective regimen for achieving recanalization in our model of intracranial thrombosis. Further studies are required in experimental models to determine the optimal dose, method of administration and efficacy of these medications in acute ischemic stroke.
    Neuroradiology 12/2005; 47(11):845-54. DOI:10.1007/s00234-003-1097-7 · 2.49 Impact Factor
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    ABSTRACT: Animal aneurysm models are required for the study of the hemodynamics and pathophysiology of intracranial aneurysms in humans and so that experimental treatments can be tested prior to clinical trials. The authors developed a canine model that consistently produces up to three bifurcation aneurysms similar in morphological features and hemodynamics to human intracranial aneurysms. In 10 mongrel dogs, a harvested segment of the external jugular vein was anastamosed to an external carotid artery (CA)-lingual artery bifurcation arteriotomy site to create a lateral bifurcation aneurysm. The surgery was repeated on the contralateral side in each animal to form a second lateral bifurcation aneurysm and, in five dogs, a CA-CA crossover anastomosis was also performed to create a terminal bifurcation aneurysm. Nineteen of 20 lateral bifurcation aneurysms were confirmed in 10 dogs by diagnostic angiography 7 to 14 days after surgery. Aneurysm fundus-to-neck ratios ranged from 1 to 2, depending on the size of the arteriotomy. The terminal bifurcation aneurysms were confirmed in all five dogs by diagnostic angiography 7 to 14 days after the procedure. The authors later tested endovascular techniques for embolizing the aneurysms. Three bifurcation aneurysms of sufficient size for endovascular access can be created in a reproducible fashion in the same animal. This model is useful for studying complex endovascular procedures in aneurysms that mimic the human condition and for testing new devices and techniques.
    Journal of Neurosurgery 11/2005; 103(4):739-44. DOI:10.3171/jns.2005.103.4.0739 · 3.74 Impact Factor
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    ABSTRACT: The authors determined the technical success and the clinical and angiographic results of angioplasty and/or stent placement for intracranial atherosclerotic disease (ICAD) at a tertiary-care referral hospital. Angiographic and clinical outcomes occurring within the 1-month follow-up interval were recorded. Patients were followed up for a mean period of 20.5 +/- 9.2 months, and a neurovascular imaging study was performed in 18 of the 21 patients alive after a mean period of 19.7 +/- 9.2 months. Stroke-free survival and ipsilateral stroke-prevention rates were estimated using Kaplan Meier analyses. Twenty-four patients (mean age = 61.0 +/- 13.5 years; 15 were men) underwent 30 procedures for treatment of ICAD. The procedures included angioplasty (n = 18) and attempted primary stent placement (n = 14). In 2 procedures, angioplasty was performed in the same session after unsuccessful stent placement. There was immediate stenosis reduction (mean +/- SD) from 84% +/- 17% to 27% +/- 21%. The overall 1-month composite rate of major stroke, death, and major bleeding complications was 7% for the 30 procedures. Overall stroke-free survival at 36 months was estimated as 79% (95% confidence interval, 57%-91%), and the ipsilateral stroke-prevention rate was estimated to be 87% (95% confidence interval, 65%-95%). Among the 15 patients who underwent repeat angiography, restenosis requiring second intervention was observed in 1 patient. No restenosis could be identified in 3 patients who underwent computed tomographic or magnetic resonance angiography. This single-center study demonstrates the feasibility and effectiveness (for secondary stroke prevention) of angioplasty and/or stent placement for treatment of ICAD.
    Journal of Neuroimaging 08/2005; 15(3):240-9. DOI:10.1177/1051228405277343 · 1.73 Impact Factor
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    ABSTRACT: During angiography, blood flow is visualized with a radiopaque contrast agent, which is denser than blood. In complex vasculature, such as cerebral saccular aneurysms, the density difference may produce an appreciable gravity effect, where the contrast material separates from blood and settles along the gravity direction. Although contrast settling has been occasionally reported before, the fluid mechanics behind it have not been explored. Furthermore, the severity of contrast settling in cerebral aneurysms varies significantly from case to case. Therefore, a better understanding of the physical principles behind this phenomenon is needed to evaluate contrast settling in clinical angiography. In this study, flow in two identical groups of sidewall aneurysm models with varying parent-vessel curvature was examined by angiography. Intravascular stents were deployed into one group of the models. To detect contrast settling, we used lateral view angiography. Time-intensity curves were analysed from the angiographic data, and a computational fluid dynamic analysis was conducted. Results showed that contrast settling was strongly related to the local flow dynamics. We used the Froude number, a ratio of flow inertia to gravity force, to characterize the significance of gravity force. An aneurysm with a larger vessel curvature experienced higher flow, which resulted in a larger Froude number and, thus, less gravitational settling. Addition of a stent reduced the aneurysmal flow, thereby increasing the contrast settling. We found that contrast settling resulted in an elevated washout tail in the time-intensity curve. However, this signature is not unique to contrast settling. To determine whether contrast settling is present, a lateral view should be obtained in addition to the anteroposterior (AP) view routinely used clinically so as to rule out contrast settling and hence to enable a valid time-intensity curve analysis of blood flow in the aneurysm.
    Physics in Medicine and Biology 08/2005; 50(13):3171-81. DOI:10.1088/0031-9155/50/13/014 · 2.76 Impact Factor
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    ABSTRACT: The purpose of this article is to describe several inadvertent perforations of external carotid artery branches that occurred in our laboratory during planned carotid artery stenting procedures. When known, the mechanism of the perforation is described. The treatment of these complications is discussed, along with a more general discussion of potential embolic materials. Perforation of branch arteries within the external carotid artery territory during planned carotid revascularization is an uncommon but potentially life-threatening complication. This complication can occur as a result of wire or catheter placement into these vessels. Early recognition of the perforation, prompt treatment of the bleeding, and control of the patient's airway are necessary to avoid a potentially catastrophic outcome.
    The Journal of invasive cardiology 07/2005; 17(6):292-5. · 0.95 Impact Factor
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    ABSTRACT: Daughter aneurysms have been strongly associated with saccular aneurysm rupture. We constructed a mathematical model to help explain this association as a possible hemodynamic mechanism for intracranial saccular aneurysm rupture. Our model is based on the assumption that when an aneurysm reaches a state of imminent rupture, the weakest area of the aneurysm wall responds passively to a surge of intra-aneurysmal pressure by forming a daughter aneurysm that will be the site of the eventual rupture. The daughter and parent aneurysms were assumed to be spherical. Using mathematical modeling, the growth of the daughter aneurysm was observed. To obtain the change in tensile stress in the daughter aneurysm wall under constant pressure and changing geometry, the Law of Laplace was applied to the parent and the daughter aneurysms. The model reveals that the stress factor, i.e. tensile stress in the daughter aneurysm wall relative to the wall strength (rupture point), is dependent on two geometric parameters: the orifice factor (mu), which represents the relative size of the daughter aneurysm orifice radius to the parent aneurysm radius; and the aspect ratio (lambda), which represents the height-to-orifice ratio of the daughter aneurysm. As the daughter aneurysm develops, the stress factor first decreases to protect against rupture. Minimal stress is attained at an aspect ratio (lambda) of 0.577 regardless of the orifice factor. This is a relatively stable state. Further growth of the daughter aneurysm results in an increase of stress above the minimum, eventually leading to rupture at a stress factor of 1. A smaller orifice factor mu allows this aneurysm to grow to a higher aspect ratio lambda before rupture. Daughter aneurysm formation is a likely path to aneurysm rupture. The formation of a daughter aneurysm temporarily decreases the tensile stress within a parent aneurysm in which rupture is imminent, indicating a temporary protective role of daughter aneurysm development. Aneurysms harboring daughter aneurysms are at a more advanced stage of development, hence at a greater risk for rupture. The severity of the rupture risk can be estimated on the basis of daughter aneurysm geometry; aspect ratio lambda > 0.577 indicates a greater risk of rupture. Furthermore, daughter aneurysms with larger orifices are associated with a greater risk of rupture.
    Neurological Research 07/2005; 27(5):459-65. DOI:10.1179/016164105X25171 · 1.44 Impact Factor
  • Elad I Levy · Lee R Guterman · L Nelson Hopkins
    Neurosurgery Clinics of North America 05/2005; 16(2):xiii-xv. DOI:10.1016/j.nec.2004.12.001 · 1.44 Impact Factor
  • Johnathan A Engh · Elad I Levy · Jay U Howington · Lee R Guterman
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    ABSTRACT: The tremendous importance of intracranial atherosclerotic disease cannot be overestimated. Traditionally, patients with this condition have been managed by neurologists and internists. As the inadequacy of medical therapy has come to light, neurosurgeons and neurointerventionists have begun to pay more attention to this highly prevalent problem. The newfound interest in this disease is well justified: intracranial atherosclerotic stenosis is more prevalent and more dangerous than unruptured cerebral aneurysms and arteriovenous malformations put together [15]. It is essential that we maintain our focus regarding the relative frequency and importance of the diseases that we treat as physicians so as to deliver the best therapies to the largest number of patients. Over the next few years, a rigorous assessment of the efficacy of coated stents compared with medical therapy for the treatment of intracranial atherosclerotic disease will provide another step toward the goal of adequately managing this difficult problem.
    Neurosurgery Clinics of North America 05/2005; 16(2):297-308, ix. DOI:10.1016/j.nec.2004.08.014 · 1.44 Impact Factor
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    ABSTRACT: Three-dimensional (3D) vessel data from CTA or MRA are not always available prior to or during endovascular interventional procedures, whereas multiple 2D projection angiograms often are. Therefore, we are developing methods for combining vessel data from multiple 2D angiographic views obtained during interventional procedures to provide 3D vessel data during these procedures. Multiple projection views of vessel trees are obtained. Vessel regions to be analyzed are selected. One of the 2D images is selected as a common image. Initial pairwise imaging geometry relationships are calculated from the gantry information, and 3D vessel centerlines are calculated using pairwise epipolar constraints. The imaging geometries of each of the other views (relative to that of the common image) are then refined by using multidimensional optimization so as to minimize the differences between all pairwise calculated 3D vessel centerlines, and an average centerline is calculated. This final 3D centerline of the carotid vessel is used for calculation of the tortuousity, a quantity related to curvature. The centerlines calculated using the multiple projection approach are in better agreement (1.3 mm) than those calculated using the biplane technique (9.0 mm), and the tortuousity is more continuous along the vessel. Use of multiple projections improves D reconstruction of vessel centerlines and tortuousity reliability, which may facilitate image guided interventions.
    International Congress Series 05/2005; 1281:334-338. DOI:10.1016/j.ics.2005.03.122
  • Brian Jankowitz · Elad I Levy · L Nelson Hopkins · Lee R Guterman
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    ABSTRACT: Catheter-based cerebral angiography remains an important method of garnering information about the cerebrovasculature. Although noninvasive imaging continues to supplant this gold standard, evidence-based medicine regarding the equivalence of these imaging modalities to DSA is lacking and studies need to be completed. When clinicians rely on a study to make surgical decisions, they must concede to the existing evidence when choosing the optimal method of diagnostic evaluation.
    Neurosurgery Clinics of North America 05/2005; 16(2):241-8, vii. DOI:10.1016/j.nec.2004.08.002 · 1.44 Impact Factor
  • Mark R Harrigan · Lee R Guterman
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    ABSTRACT: Acute ischemic stroke is a major public health threat. Intravenous thrombolysis has been shown in several randomized clinical trials to improve outcomes in selected patients, and intravenous t-PA is currently approved by the FDA for patients presenting within 3 hours of symptom onset. Three generations of thrombolytic agents have been introduced. Intra-arterial thrombolysis offers several potential advantages over intravenous thrombolysis for acute stroke, such as precise diagnosis and the opportunity to reduce the overall dose of thrombolytic agent used, and thus lowers the chance of ICH. The PROACT trials showed that intra-arterial thrombolysis can improve recanalization rates and outcomes in patients presenting with MCA occlusions up to 6 hours after symptom onset. Alternative strategies for endovascular treatment of acute stroke include combination intravenous-intra-arterial administration of thrombolytic agents, use of GP IIb-IIIa antagonists, and mechanical thrombolysis. Options for mechanical thrombolysis include microsnares, the In-Time thrombus retrieval device, angioplasty, and suction thrombectomy. Several investigational devices are undergoing clinical evaluation. The PROACT enrollment criteria can serve as guidelines for patient selection. Radiographic evaluation of acute stroke patients begins with imaging to exclude the presence of ICH; recent developments in CT and MRI perfusion promise to permit identification of patients who will benefit from thrombolysis with greater precision.
    Neurosurgery Clinics of North America 05/2005; 16(2):433-44, xi. DOI:10.1016/j.nec.2004.08.009 · 1.44 Impact Factor

Publication Stats

5k Citations
545.65 Total Impact Points


  • 1992–2006
    • State University of New York
      New York City, New York, United States
  • 2005
    • Wayne State University
      Detroit, Michigan, United States
    • University of Pittsburgh
      Pittsburgh, Pennsylvania, United States
  • 1993–2005
    • University at Buffalo, The State University of New York
      • • Department of Neurosurgery
      • • School of Medicine and Biomedical Sciences
      Buffalo, New York, United States
  • 2003
    • University of Alberta
      • Department of Psychiatry
      Edmonton, Alberta, Canada
  • 2002–2003
    • University of Cincinnati
      • Department of Neurosurgery
      Cincinnati, Ohio, United States
    • University of Colorado
      Denver, Colorado, United States
    • The Ohio State University
      Columbus, Ohio, United States
  • 2001
    • Uniformed Services University of the Health Sciences
      베서스다, Maryland, United States
  • 2000
    • University of Florida
      • College of Medicine
      Gainesville, FL, United States
  • 1996
    • Erie County Medical Center
      New York City, New York, United States
  • 1994
    • Dent Neurologic Institute
      Buffalo, New York, United States