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Lin K, Zink WE, Tsiouris AJ, John M, Tekchandani L, Sanelli PC. Risk assessment of hemorrhagic transformation of acute middle cerebral artery stroke using multimodal CT. J Neuroimaging 2010; 22:160-6. [PMID: 21143549 DOI: 10.1111/j.1552-6569.2010.00562.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
PURPOSE Multimodal CT with CT angiography (CTA) and CT perfusion (CTP) are increasingly used in stroke triage. Our aim was to identify parameters most predictive of hemorrhagic transformation (HT), especially symptomatic intracerebral hemorrhage (SICH). METHODS This retrospective study included patients evaluated by baseline multimodal CT ≤ 9 hours from ictus with acute nonlacunar middle cerebral artery (MCA) territory infarction. Two readers independently evaluated CTP maps for ischemic severity and CTA source images (CTA-SI) for infarct extent (as measured by ASPECTS). Presence of proximal occlusion (ICA or M1) and degree of collateralization (collateral score) were also assessed on CTA. HT was defined as SICH if associated with deterioration ≥ 4-points on NIHSS. Multivariate logistic regression analysis identified independent predictors of SICH. ROC curves selected optimal thresholds. RESULTS Of 84 patients reviewed, HT occurred in 22 (26.2%) and SICH in 8 (9.5%). Univariate predictors for SICH were proximal occlusion (OR = 8.65, P= .049), collateral score (OR = .34, P= .017), ASPECTS (OR = .46, P= .001), and CBV (OR = .001, P= .005). Multivariate analysis revealed ASPECTS as the only independent predictor with optimal threshold ≤ 5 and sensitivity and specificity of 75.0% and 85.5%, respectively. CONCLUSION For acute MCA infarcts ≤ 9 hours, the strongest predictor of SICH on multimodal CT was ASPECTS on CTA-SI.
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Affiliation(s)
- Ke Lin
- Department of Radiology, New York Presbyterian Hospital, Weill-Cornell Medical College, New York, NY, USA.
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Li YH, Li MH, Zhao JG, Wang W. MRI-based ultrafast protocol thrombolysis with rt-PA for acute ischemia stroke in 12-hour time window. J Neuroimaging 2010; 21:332-9. [PMID: 21121996 DOI: 10.1111/j.1552-6569.2010.00544.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
PURPOSE To evaluate the safety of thrombolysis with rt-PA in acute ischemic strokes during a 12-hour time window using an ultrafast MR protocol. METHODS Forty-six patients who met the clinical criteria (acute ischemic stroke within 12 hours after symptom onset; National Institutes of Health stroke scale score (NIHSS) of 4 to 22 and no intracranial hemorrhage on CT) and MRI selection criteria (acute ischemic stroke except lacunar and large DWI lesion) were treated with intravenous rt-PA. MRI was performed before rt-PA, and at 24 hours, 7 days, and 14 days after stroke. Clinical status was assessed using the NIHSS and Modified Rankin scale (mRS). RESULTS From 46 MRI-selected rt-PA patients, 43.5% (n= 20) were treated ≤3 hours (group A) and 56.5% (n= 26) after 3 to 12 hours (group B). No patients experienced symptomatic intracranial hemorrhage and the mortality rate was zero. No significant differences in age, gender, MRI lesion volumes, NIHSS score, and mRS were found between the 2 groups. Forty-five percent of the patients in group A and 46% in group B experienced a favorable outcome (P= .938). CONCLUSION Our results demonstrated the safety of thrombolysis with rt-PA in selected stroke patients within a 12-hour time window using an ultrafast MR protocol.
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Affiliation(s)
- Yue-Hua Li
- Institute of Diagnostic and Interventional Radiology, The Sixth Affiliated People's Hospital, Shanghai Jiao Tong University.
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Lee SJ, Saver JL, Liebeskind DS, Ali L, Ovbiagele B, Kim D, Vespa P, Froehler M, Tenser M, Gadhia J, Starkman S. Safety of intravenous fibrinolysis in imaging-confirmed single penetrator artery infarcts. Stroke 2010; 41:2587-91. [PMID: 20947857 DOI: 10.1161/strokeaha.110.586248] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Hemorrhagic transformation (HT) after fibrinolytic therapy may be less common in patients with acute cerebral ischemia confined to single penetrator artery (SPA) territories than in patients with large artery ischemia. Previous investigations of HT diagnosed small vessel ischemia based on lacunar clinical syndromes, an approach known to yield misdiagnosis in one-third to one-half of cases. METHODS Consecutive intravenous tissue plasminogen activator-treated patients in a prospectively maintained hospital registry were analyzed. Patients were classified as having SPA ischemia if they had imaging evidence of: (1) deep location; (2) diameter ≤ 1.5 cm; and (3) distribution in a single penetrator territory, regardless of presenting clinical syndrome. Lacunar clinical syndrome was defined according to the Oxfordshire Community Stroke Project classification. RESULTS Among 93 intravenous tissue plasminogen activator-treated patients, mean age was 71.5, 62.4% were female, and median pretreatment National Institutes of Health Stroke Scale score was 14. Single penetrator artery ischemia was imaged in 13 (14.0%) and large artery ischemia was imaged in 75 (80.6%), with no visualized ischemic injury in 5 (5.4%). Lacunar clinical syndromes were present in 23 (24.7%), including 10 with SPA ischemia and 9 with large artery ischemia. No patient with imaging-confirmed SPA infarcts experienced any hemorrhagic transformation, whereas any radiological HT occurred in 29.3% of large artery infarcts (P=0.03). Symptomatic intracerebral hemorrhage occurred in 0% of SPA infarcts vs 4.0% of large artery infarcts. CONCLUSIONS HT after lytic therapy in imaging-confirmed SPA infarcts is uncommon. Imaging demonstration of ischemia confined to SPA territory better-identifies this population at low risk for hemorrhagic complications than clinical lacunar syndromes.
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Affiliation(s)
- Soo Joo Lee
- Department of Neurology, Eulji University Hospital, School of Medicine Eulji University, Eulji, South Korea
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Kidwell CS, Wintermark M. The role of CT and MRI in the emergency evaluation of persons with suspected stroke. Curr Neurol Neurosci Rep 2010; 10:21-8. [PMID: 20425222 DOI: 10.1007/s11910-009-0075-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
As a growing number of therapeutic treatment options for acute stroke are being introduced, multimodal acute neuroimaging is assuming a growing role in the initial evaluation and management of patients. Multimodal neuroimaging, using either a CT or MRI approach, can identify the type, location, and severity of the lesion (ischemia or hemorrhage); the status of the cerebral vasculature; the status of cerebral perfusion; and the existence and extent of the ischemic penumbra. Both acute and long-term treatment decisions for stroke patients can then be optimally guided by this information.
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Affiliation(s)
- Chelsea S Kidwell
- Georgetown University Medical Center, 4000 Reservoir Road, Northwest, Building D, Suite 150, Washington, DC, 20007, USA.
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Lin K, Lee SA, Zink WE. What ASPECTS Value Best Predicts the 100-mL Threshold on Diffusion Weighted Imaging? Study of 150 Patients with Middle Cerebral Artery Stroke. J Neuroimaging 2010; 21:229-31. [DOI: 10.1111/j.1552-6569.2010.00487.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Hopyan J, Ciarallo A, Dowlatshahi D, Howard P, John V, Yeung R, Zhang L, Kim J, MacFarlane G, Lee TY, Aviv RI. Certainty of stroke diagnosis: incremental benefit with CT perfusion over noncontrast CT and CT angiography. Radiology 2010; 255:142-53. [PMID: 20308452 DOI: 10.1148/radiol.09091021] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To systematically evaluate the diagnostic benefits and inter- and intraobserver reliability of an incremental computed tomographic (CT) protocol in the confirmation of clinically suspected stroke, with combined imaging and clinical data as the reference standard. MATERIALS AND METHODS Institutional review board approval was obtained, and participants gave informed consent. A total of 191 patients (mean age, 67 years +/- 16 [standard deviation]; 105 men) with strokelike symptoms of no more than 3 hours duration were recruited. Blinded review was performed by four readers with limited stroke imaging experience. Diagnostic confidence was recorded on a five-point scale. Logistic regression analysis was used to calculate the difference between the real and observed diagnoses, adjusting for confidence. Predictive effects of observed diagnostic performance and confidence score were quantified with the entropy r(2) value. Sensitivity, specificity, and confidence intervals were calculated while accounting for multiple reader assessments. Receiver operating characteristic (ROC) analyses, including area under the ROC curve, were conducted for three modalities in combination with confidence score. Inter- and intraobserver agreement was established with the Cohen kappa statistic. RESULTS The final diagnosis was infarct in 64% of the patients, transient ischemic attack in 18%, and stroke mimic in 17%. Large-vessel occlusion occurred in 70% of the patients with an infarct. Sensitivity for stroke determination with noncontrast CT, CT angiography, and CT perfusion increased by 12.4% over that with noncontrast CT and CT angiography and by 18.2% over that with only noncontrast CT for a confidence level of 4 or higher. The incremental protocol was more likely to enable confirmation of clinical stroke diagnosis (odds ratio, 13.3) than was noncontrast CT and CT angiography (odds ratio, 6.4) or noncontrast CT alone (odds ratio, 3.3), The area under the ROC curve was 0.67 for the combination of noncontrast CT and confidence score, 0.72 for the combination of CT angiography and confidence score, and 0.81 for the combination of CT perfusion and confidence score. Inter- and intraobserver agreement increased with progressive sequence use. CONCLUSION An incremental stroke protocol that includes CT perfusion increases diagnostic performance for stroke diagnosis and inter- and intraobserver agreement.
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Affiliation(s)
- Julia Hopyan
- Department of Diagnostic Imaging, Division of Neuroradiology, Room AG 31, Sunnybrook Health Sciences Centre, 2075 Bayview Ave, Toronto, ON, Canada M4N 3M5
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Using Advanced MRI Techniques for Patient Selection Before Acute Stroke Therapy. CURRENT TREATMENT OPTIONS IN CARDIOVASCULAR MEDICINE 2010; 12:230-9. [DOI: 10.1007/s11936-010-0072-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Martínez-Hernández E, Martínez-Ramírez S, Delgado-Mederos R, Alcolea D, Marquié M, Marín R, De Juan M, Martí-Vilalta JL, Martí-Fàbregas J. Remote cerebral hematomas in patients treated with intravenous rt-PA. J Neurol 2010; 257:1062-6. [DOI: 10.1007/s00415-010-5462-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2009] [Revised: 12/14/2009] [Accepted: 01/11/2010] [Indexed: 10/19/2022]
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Kim JH, Bang OY, Liebeskind DS, Ovbiagele B, Kim GM, Chung CS, Lee KH, Saver JL. Impact of baseline tissue status (diffusion-weighted imaging lesion) versus perfusion status (severity of hypoperfusion) on hemorrhagic transformation. Stroke 2010; 41:e135-42. [PMID: 20075362 DOI: 10.1161/strokeaha.109.563122] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE The frequency of hemorrhagic transformation (HT) on gradient echo imaging and its impact on stroke outcomes continues to be debated. We investigated the factors associated with HTs and the influence of the HTs observed on gradient echo imaging on the early course after a stroke. METHODS We analyzed the data from a prospectively maintained registry of patients who were eligible for recanalization therapy. Serial diffusion-weighted imaging and perfusion-weighted imaging were performed, and HTs were assessed on follow-up gradient echo imaging. Tmax perfusion lesion maps were generated and hypoperfused regions were divided into severe (Tmax >or=8 seconds) delay and mild (Tmax >or=2 seconds but Tmax <8 seconds) delay. The factors associated with HTs, including the mode of recanalization therapy, pretreatment diffusion-weighted imaging and perfusion-weighted imaging lesion volumes, and reperfusion indices, were evaluated. The early clinical outcome was assessed during the first 7 days of admission. RESULTS A total of 184 patients were included in this study. HTs were noted in 73 (39.7%) patients. Multiple logistic regression analysis identified aggressive treatment (OR, 5.12; 95% CI, 1.73 to 15.18) and a large area of severe perfusion delay (OR for highest quartile of Tmax >8 seconds, 12.91; 95% CI, 3.69 to 45.17) as independent predictors of HTs. Neither risk factor profiles nor diffusion-weighted imaging lesion volumes were associated with HTs. There was a poor correlation between the radiological (HT types) and clinical (asymptomatic or symptomatic) categories of HTs. Even a parenchymal hematoma was not always associated with symptomatic worsening or affected the early clinical outcomes. CONCLUSIONS The results of this study indicate that the perfusion status (severe perfusion delay) rather than the tissue status (diffusion-weighted imaging lesions) and aggressive treatment were independently associated with HTs. HT on gradient echo imaging was common but usually associated with severe hypoperfusion and not always associated with clinical deterioration.
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Affiliation(s)
- Jong Hun Kim
- Department of Neurology, Stroke Center, Samsung Medical Center, Seoul, South Korea
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Butcher K, Christensen S, Parsons M, De Silva DA, Ebinger M, Levi C, Jeerakathil T, Campbell BC, Barber PA, Bladin C, Fink J, Tress B, Donnan GA, Davis SM. Postthrombolysis Blood Pressure Elevation Is Associated With Hemorrhagic Transformation. Stroke 2010; 41:72-7. [DOI: 10.1161/strokeaha.109.563767] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Kenneth Butcher
- From the Division of Neurology (K.B., T.J.), University of Alberta, Edmonton, Alberta, Canada; Departments of Neurology (K.B., S.C., D.D.S., M.E., B.C.V.C., S.M.D.) and Radiology (B.T.), Royal Melbourne Hospital, University of Melbourne, Melbourne, and Department of Neurology (M.P., C.L.), John Hunter Hospital, Newcastle, Australia; Center for Stroke Research (M.E.), Berlin, Germany; Singapore General Hospital Campus (D.D.S.), National Neuroscience Institute, Singapore; Neurology Research Unit (P.A
| | - Søren Christensen
- From the Division of Neurology (K.B., T.J.), University of Alberta, Edmonton, Alberta, Canada; Departments of Neurology (K.B., S.C., D.D.S., M.E., B.C.V.C., S.M.D.) and Radiology (B.T.), Royal Melbourne Hospital, University of Melbourne, Melbourne, and Department of Neurology (M.P., C.L.), John Hunter Hospital, Newcastle, Australia; Center for Stroke Research (M.E.), Berlin, Germany; Singapore General Hospital Campus (D.D.S.), National Neuroscience Institute, Singapore; Neurology Research Unit (P.A
| | - Mark Parsons
- From the Division of Neurology (K.B., T.J.), University of Alberta, Edmonton, Alberta, Canada; Departments of Neurology (K.B., S.C., D.D.S., M.E., B.C.V.C., S.M.D.) and Radiology (B.T.), Royal Melbourne Hospital, University of Melbourne, Melbourne, and Department of Neurology (M.P., C.L.), John Hunter Hospital, Newcastle, Australia; Center for Stroke Research (M.E.), Berlin, Germany; Singapore General Hospital Campus (D.D.S.), National Neuroscience Institute, Singapore; Neurology Research Unit (P.A
| | - Deidre A. De Silva
- From the Division of Neurology (K.B., T.J.), University of Alberta, Edmonton, Alberta, Canada; Departments of Neurology (K.B., S.C., D.D.S., M.E., B.C.V.C., S.M.D.) and Radiology (B.T.), Royal Melbourne Hospital, University of Melbourne, Melbourne, and Department of Neurology (M.P., C.L.), John Hunter Hospital, Newcastle, Australia; Center for Stroke Research (M.E.), Berlin, Germany; Singapore General Hospital Campus (D.D.S.), National Neuroscience Institute, Singapore; Neurology Research Unit (P.A
| | - Martin Ebinger
- From the Division of Neurology (K.B., T.J.), University of Alberta, Edmonton, Alberta, Canada; Departments of Neurology (K.B., S.C., D.D.S., M.E., B.C.V.C., S.M.D.) and Radiology (B.T.), Royal Melbourne Hospital, University of Melbourne, Melbourne, and Department of Neurology (M.P., C.L.), John Hunter Hospital, Newcastle, Australia; Center for Stroke Research (M.E.), Berlin, Germany; Singapore General Hospital Campus (D.D.S.), National Neuroscience Institute, Singapore; Neurology Research Unit (P.A
| | - Christopher Levi
- From the Division of Neurology (K.B., T.J.), University of Alberta, Edmonton, Alberta, Canada; Departments of Neurology (K.B., S.C., D.D.S., M.E., B.C.V.C., S.M.D.) and Radiology (B.T.), Royal Melbourne Hospital, University of Melbourne, Melbourne, and Department of Neurology (M.P., C.L.), John Hunter Hospital, Newcastle, Australia; Center for Stroke Research (M.E.), Berlin, Germany; Singapore General Hospital Campus (D.D.S.), National Neuroscience Institute, Singapore; Neurology Research Unit (P.A
| | - Thomas Jeerakathil
- From the Division of Neurology (K.B., T.J.), University of Alberta, Edmonton, Alberta, Canada; Departments of Neurology (K.B., S.C., D.D.S., M.E., B.C.V.C., S.M.D.) and Radiology (B.T.), Royal Melbourne Hospital, University of Melbourne, Melbourne, and Department of Neurology (M.P., C.L.), John Hunter Hospital, Newcastle, Australia; Center for Stroke Research (M.E.), Berlin, Germany; Singapore General Hospital Campus (D.D.S.), National Neuroscience Institute, Singapore; Neurology Research Unit (P.A
| | - Bruce C.V. Campbell
- From the Division of Neurology (K.B., T.J.), University of Alberta, Edmonton, Alberta, Canada; Departments of Neurology (K.B., S.C., D.D.S., M.E., B.C.V.C., S.M.D.) and Radiology (B.T.), Royal Melbourne Hospital, University of Melbourne, Melbourne, and Department of Neurology (M.P., C.L.), John Hunter Hospital, Newcastle, Australia; Center for Stroke Research (M.E.), Berlin, Germany; Singapore General Hospital Campus (D.D.S.), National Neuroscience Institute, Singapore; Neurology Research Unit (P.A
| | - P. Alan Barber
- From the Division of Neurology (K.B., T.J.), University of Alberta, Edmonton, Alberta, Canada; Departments of Neurology (K.B., S.C., D.D.S., M.E., B.C.V.C., S.M.D.) and Radiology (B.T.), Royal Melbourne Hospital, University of Melbourne, Melbourne, and Department of Neurology (M.P., C.L.), John Hunter Hospital, Newcastle, Australia; Center for Stroke Research (M.E.), Berlin, Germany; Singapore General Hospital Campus (D.D.S.), National Neuroscience Institute, Singapore; Neurology Research Unit (P.A
| | - Christopher Bladin
- From the Division of Neurology (K.B., T.J.), University of Alberta, Edmonton, Alberta, Canada; Departments of Neurology (K.B., S.C., D.D.S., M.E., B.C.V.C., S.M.D.) and Radiology (B.T.), Royal Melbourne Hospital, University of Melbourne, Melbourne, and Department of Neurology (M.P., C.L.), John Hunter Hospital, Newcastle, Australia; Center for Stroke Research (M.E.), Berlin, Germany; Singapore General Hospital Campus (D.D.S.), National Neuroscience Institute, Singapore; Neurology Research Unit (P.A
| | - John Fink
- From the Division of Neurology (K.B., T.J.), University of Alberta, Edmonton, Alberta, Canada; Departments of Neurology (K.B., S.C., D.D.S., M.E., B.C.V.C., S.M.D.) and Radiology (B.T.), Royal Melbourne Hospital, University of Melbourne, Melbourne, and Department of Neurology (M.P., C.L.), John Hunter Hospital, Newcastle, Australia; Center for Stroke Research (M.E.), Berlin, Germany; Singapore General Hospital Campus (D.D.S.), National Neuroscience Institute, Singapore; Neurology Research Unit (P.A
| | - Brian Tress
- From the Division of Neurology (K.B., T.J.), University of Alberta, Edmonton, Alberta, Canada; Departments of Neurology (K.B., S.C., D.D.S., M.E., B.C.V.C., S.M.D.) and Radiology (B.T.), Royal Melbourne Hospital, University of Melbourne, Melbourne, and Department of Neurology (M.P., C.L.), John Hunter Hospital, Newcastle, Australia; Center for Stroke Research (M.E.), Berlin, Germany; Singapore General Hospital Campus (D.D.S.), National Neuroscience Institute, Singapore; Neurology Research Unit (P.A
| | - Geoffrey A. Donnan
- From the Division of Neurology (K.B., T.J.), University of Alberta, Edmonton, Alberta, Canada; Departments of Neurology (K.B., S.C., D.D.S., M.E., B.C.V.C., S.M.D.) and Radiology (B.T.), Royal Melbourne Hospital, University of Melbourne, Melbourne, and Department of Neurology (M.P., C.L.), John Hunter Hospital, Newcastle, Australia; Center for Stroke Research (M.E.), Berlin, Germany; Singapore General Hospital Campus (D.D.S.), National Neuroscience Institute, Singapore; Neurology Research Unit (P.A
| | - Stephen M. Davis
- From the Division of Neurology (K.B., T.J.), University of Alberta, Edmonton, Alberta, Canada; Departments of Neurology (K.B., S.C., D.D.S., M.E., B.C.V.C., S.M.D.) and Radiology (B.T.), Royal Melbourne Hospital, University of Melbourne, Melbourne, and Department of Neurology (M.P., C.L.), John Hunter Hospital, Newcastle, Australia; Center for Stroke Research (M.E.), Berlin, Germany; Singapore General Hospital Campus (D.D.S.), National Neuroscience Institute, Singapore; Neurology Research Unit (P.A
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Yun YH, Chung JY, Kang MJ, Huh JT, Park KW, Cha JK. A Retrospective Study on Intracerebral Haemorrhage Reduction by Mri versus Ct in Intravenous Thrombolysis for Acute Ischaemic Stroke. HONG KONG J EMERG ME 2010. [DOI: 10.1177/102490791001700102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Introduction Multimodal MRI may be an effective tool for selecting suitable acute ischaemic stroke patients for thrombolysis, reducing the risk of haemorrhage. In this study, we demonstrated the usefulness of our central alerting system to reduce door-to-needle time for thrombolysis following MRI. This system allowed timely intervention and reduced the rate of symptomatic haemorrhage. Methods We reviewed the records of 73 patients with hyperacute ischaemic stroke who received intravenous (IV) tissue plasminogen activator (t-PA) between January 2006 and December 2007 following the adoption of a central stroke alerting system in our hospital. Results Of the 73 patients who received IV t-PA, 44 were based on CT and 29 on MRI findings. The door-to-needle time was 10 minutes longer for the MRI group (49.9±23.2 min) compared to the CT group (39.6±19.7 min) but it was still within the recommended 60 minutes time frame. On the other hand, the rate of symptomatic haemorrhage was lower, though insignificantly, in the MRI group (0%) compared to the CT group (13.6%) (p=0.08). Conclusions In this study, we demonstrated that the combination of diagnostic MRI and a central alerting system might reduce the rate of symptomatic haemorrhage without compromising the door-to-needle time.
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Affiliation(s)
- YH Yun
- Dong-A University College of Medicine, Department of Emergency Medicine, Busan, Korea
| | - JY Chung
- Dong-A University College of Medicine, Department of Emergency Medicine, Busan, Korea
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Thijs V. Imaging techniques for acute ischemic stroke: nice gadgets or essential tools for effective treatment? Neuroradiology 2009; 52:169-71. [PMID: 20016884 DOI: 10.1007/s00234-009-0638-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2009] [Accepted: 11/17/2009] [Indexed: 10/20/2022]
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Campbell BCV, Christensen S, Butcher KS, Gordon I, Parsons MW, Desmond PM, Barber PA, Levi CR, Bladin CF, De Silva DA, Donnan GA, Davis SM. Regional very low cerebral blood volume predicts hemorrhagic transformation better than diffusion-weighted imaging volume and thresholded apparent diffusion coefficient in acute ischemic stroke. Stroke 2009; 41:82-8. [PMID: 19959537 DOI: 10.1161/strokeaha.109.562116] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Currently, diffusion-weighted imaging (DWI) lesion volume is the most useful magnetic resonance imaging predictor of hemorrhagic transformation (HT). Preliminary studies have suggested that very low cerebral blood volume (VLCBV) predicts HT. We compared HT prediction by VLCBV and DWI using data from the EPITHET study. METHODS Normal-percentile CBV values were calculated from the nonstroke hemisphere. Whole-brain masks with CBV thresholds of the <0, 2.5, 5, and 10th percentiles were created. The volume of tissue with VLCBV was calculated within the acute DWI ischemic lesion. HT was graded as per ECASS criteria. RESULTS HT occurred in 44 of 91 patients. Parenchymal hematoma (PH) occurred in 13 (4 symptomatic) and asymptomatic hemorrhagic infarction (HI) in 31. The median volume of VLCBV was significantly higher in cases with PH. VLCBV predicted HT better than DWI lesion volume and thresholded apparent diffusion coefficient lesion volume in receiver operating characteristic analysis and logistic regression. A cutpoint at 2 mL VLCBV with the <2.5th percentile had 100% sensitivity for PH and, in patients treated with tissue plasminogen activator, defined a population with a 43% risk of PH (95% CI, 23% to 66%, likelihood ratio=16). VLCBV remained an independent predictor of PH in multivariate analysis with traditional clinical risk factors for HT. CONCLUSIONS VLCBV predicted HT after thrombolysis better than did DWI or apparent diffusion coefficient volume in this large patient cohort. The advantage was greatest in patients with smaller DWI volumes. Prediction was better in patients who recanalized. If validated in an independent cohort, the addition of VLCBV to prethrombolysis decision making may reduce the incidence of HT.
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Affiliation(s)
- Bruce C V Campbell
- Department of Neurology, Royal Melbourne Hospital, Grattan Street, Parkville VIC 3050, Australia
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Affiliation(s)
- David S Liebeskind
- Department of Neurology, University of California Los Angeles Stroke Center, Los Angeles, CA 90095, USA.
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Bang OY. Multimodal MRI for ischemic stroke: from acute therapy to preventive strategies. J Clin Neurol 2009; 5:107-19. [PMID: 19826561 PMCID: PMC2760715 DOI: 10.3988/jcn.2009.5.3.107] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2009] [Revised: 07/17/2009] [Accepted: 07/17/2009] [Indexed: 01/09/2023] Open
Abstract
Background and Purpose Conventional therapies for ischemic stroke include thrombolytic therapy, prevention of inappropriate coagulation and thrombosis, and surgery to repair vascular abnormalities. Over 10 years have passed since the US Food and Drug Administration approved intravenous tissue plasminogen activator for use in acute stroke patients, but most major clinical trials have failed during the last 2 decades, including large clinical trials for secondary prevention and neuroprotection. These results suggest the presence of heterogeneity among stroke patients. Neuroimaging techniques now allow changes to be observed in patients from the acute to the recovery phase. The role of MRI in stroke evaluation and treatment is discussed herein. Main Contents Three MRI strategies are discussed with relevant examples. First, the following MRI strategies for acute ischemic stroke are presented: diffusion-perfusion mismatch, deoxygenation (oxygen extraction and cerebral metabolic rate of oxygen), and blood-brain barrier permeability derangement in selected patients for recanalization therapy. Second, multimodal MRI for identifying stroke mechanisms and the specific causes of stroke (i.e., patent foramen ovale, infective endocarditis, and nonbacterial thrombotic endocarditis) are presented, followed by MRI strategies for prevention of recurrent stroke: plaque images and flow dynamics for carotid intervention. Expectations The studies reviewed herein suggest that using MRI to improve the understanding of individual pathophysiologies will further promote the development of rational stroke therapies tailored to the specifics of each case.
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Affiliation(s)
- Oh Young Bang
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
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Abstract
Diffusion and perfusion MR imaging have proven to be highly useful in the clinical description and understanding of acute and hyperacute ischemic stroke. In this article, the authors give a brief overview of the basic concepts of diffusion and perfusion imaging and describe some of the current developments, applications, challenges, and limitations of these techniques as applied to cerebral ischemia.
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118
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Olivot JM, Marks MP. Magnetic resonance imaging in the evaluation of acute stroke. Top Magn Reson Imaging 2009; 19:225-30. [PMID: 19512854 DOI: 10.1097/rmr.0b013e3181aaf37c] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The ability to use physiologic imaging with either magnetic resonance (MR) or computed tomography to help define irreversibly injured brain (the infarct core) and tissue at risk of infarct (reversible ischemic penumbra) holds great promise in the future treatment of stroke. The physiologic principles and concepts underlying the evaluation for mismatch between injured tissue and tissue at risk are similar for the 2 imaging techniques. Multimodal MR imaging (diffusion-weighted imaging/perfusion-weighted imaging/MR angiography) provides a validated penumbral selection criteria based on the results of 2 clinical trials (diffusion and perfusion imaging evaluation for understanding stroke evolution and echoplanar imaging thrombolysis evaluation). Computed tomographic perfusion parameters have also been calculated to optimize final infarct prediction. Both techniques await further study to prove their capability of selecting cases for short-term recanalization/reperfusion therapy.
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Affiliation(s)
- Jean Marc Olivot
- Department of Neurology and Neuroscience, Stanford Stroke Center, Stanford University Medical Center, Stanford, CA 94305, USA
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119
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Affiliation(s)
- Stephen M Davis
- Divisional Director of Neurosciences, Director of Neurology, Royal Melbourne Hospital, Parkville Vic Australia 3050.
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Singer OC, Kurre W, Humpich MC, Lorenz MW, Kastrup A, Liebeskind DS, Thomalla G, Fiehler J, Berkefeld J, Neumann-Haefelin T. Risk assessment of symptomatic intracerebral hemorrhage after thrombolysis using DWI-ASPECTS. Stroke 2009; 40:2743-8. [PMID: 19498190 DOI: 10.1161/strokeaha.109.550111] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Pretreatment lesion size on diffusion-weighted imaging (DWI) is a risk factor for symptomatic intracerebral hemorrhage (sICH) associated with thrombolytic treatment. Here, we investigated whether the Alberta Stroke Programme Early CT Score (ASPECTS) applied to DWI images (DWI-ASPECTS) predicts sICH risk accurately. METHODS In this retrospective multicenter study, prospectively collected data of 217 patients with anterior circulation stroke treated with intravenous or intraarterial thrombolysis within 6 hours after symptom onset were analyzed. Pretreatment DWI-ASPECTS scores were assessed by 2 independent investigators. For bleeding risk analysis, DWI-ASPECTS scores were either categorized into 0 to 7 (n=105) or 8 to 10 (n=112) or in 3 groups of similar sample size (DWI-ASPECTS 0 to 5 [n=69], 6 to 7 [n=70], and 8 to 10 [n=78]). RESULTS DWI-ASPECTS scores correlated well with the DWI lesion volume (r=0.77, P<0.001, Spearman Rank test). Interobserver reliability for the assessment of DWI-ASPECTS was moderate (weighted kappa 0.441 [95% CI 0.373 to 0.509]). Twenty-three (10.6%) patients developed sICH. The sICH rate was significantly higher in patients with DWI-ASPECTS scores 0 to 7 (n=21, 15.1%) as compared to patients with DWI-ASPECTS scores 8 to 10 (n=2, 2.6%, P=0.004). sICH risk was 20.3%, 10%, and 2.6% in the 0 to 5, 6 to 7, and 8 to 10 DWI-ASPECTS groups, respectively. DWI-ASPECTS remained an independent prognostic factor for sICH after adjustment for clinical baseline variables (age, NIHSS, time to thrombolysis). CONCLUSIONS DWI-ASPECTS predicts sICH risk after thrombolysis and may be helpful to contributing to quick sICH risk assessment before thrombolytic therapy.
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Affiliation(s)
- Oliver C Singer
- Department of Neurology, J.W. Goethe-University Frankfurt am Main, Schleusenweg 2-16, D-60528 Frankfurt/Main, Germany.
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121
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Diffusion-weighted magnetic resonance imaging as a cancer biomarker: consensus and recommendations. Neoplasia 2009; 11:102-25. [PMID: 19186405 DOI: 10.1593/neo.81328] [Citation(s) in RCA: 1511] [Impact Index Per Article: 100.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
On May 3, 2008, a National Cancer Institute (NCI)-sponsored open consensus conference was held in Toronto, Ontario, Canada, during the 2008 International Society for Magnetic Resonance in Medicine Meeting. Approximately 100 experts and stakeholders summarized the current understanding of diffusion-weighted magnetic resonance imaging (DW-MRI) and reached consensus on the use of DW-MRI as a cancer imaging biomarker. DW-MRI should be tested as an imaging biomarker in the context of well-defined clinical trials, by adding DW-MRI to existing NCI-sponsored trials, particularly those with tissue sampling or survival indicators. Where possible, DW-MRI measurements should be compared with histologic indices including cellularity and tissue response. There is a need for tissue equivalent diffusivity phantoms; meanwhile, simple fluid-filled phantoms should be used. Monoexponential assessments of apparent diffusion coefficient values should use two b values (>100 and between 500 and 1000 mm2/sec depending on the application). Free breathing with multiple acquisitions is superior to complex gating techniques. Baseline patient reproducibility studies should be part of study designs. Both region of interest and histogram analysis of apparent diffusion coefficient measurements should be obtained. Standards for measurement, analysis, and display are needed. Annotated data from validation studies (along with outcome measures) should be made publicly available. Magnetic resonance imaging vendors should be engaged in this process. The NCI should establish a task force of experts (physicists, radiologists, and oncologists) to plan, organize technical aspects, and conduct pilot trials. The American College of Radiology Imaging Network infrastructure may be suitable for these purposes. There is an extraordinary opportunity for DW-MRI to evolve into a clinically valuable imaging tool, potentially important for drug development.
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Imaging in Acute Stroke – a Personal View*. Clin Neuroradiol 2009; 19:20-30. [DOI: 10.1007/s00062-009-8030-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2008] [Accepted: 10/26/2008] [Indexed: 11/27/2022]
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Berkefeld J, Neumann-Haefelin T. [Diagnosis of cerebral ischemia: when CT and when MRI?]. Radiologe 2009; 49:299-304. [PMID: 19319501 DOI: 10.1007/s00117-008-1770-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Rapid and effective diagnostic imaging is important for decision-making concerning thrombolysis in patients with acute ischemic stroke. Apart from excluding intracranial hemorrhage, CT and MRI provide multiple methodological options to define the extent of ischemic brain damage and the underlying vascular pathology. The aim of this article is to discuss the value of CT and MRI from a neurologicalneuroradiological point of view and to discuss which of the available imaging tools are really relevant for clinical decision making.
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Affiliation(s)
- J Berkefeld
- Institut für Neuroradiologie, Hirngefässzentrum, Klinikum der Goethe-Universität, Schleusenweg 2-16, 60528, Frankfurt am Main, Deutschland.
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Mechanisms and markers for hemorrhagic transformation after stroke. ACTA NEUROCHIRURGICA. SUPPLEMENT 2009; 105:173-8. [PMID: 19066105 DOI: 10.1007/978-3-211-09469-3_34] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Intracerebral hemorrhagic transformation is a multifactorial phenomenon in which ischemic brain tissue converts into a hemorrhagic lesion with blood vessel leakage. Hemorrhagic transformation can significantly contribute to additional brain injury after stroke. Especially threatening are the thrombolytic-induced hemorrhages after reperfusion therapy with tissue plasminogen activator (tPA), the only treatment available for ischemic stroke. In this context, it is important to understand its underlying mechanisms and identify early markers of hemorrhagic transformation, so that we can both search for new treatments as well as predict clinical outcomes in patients. In this review, we discuss the emerging mechanisms for hemorrhagic transformation after stroke, and briefly survey potential molecular, genetic, and neuroimaging markers that might be used for early detection of this challenging clinical problem.
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Singer OC, Berkefeld J, Lorenz MW, Fiehler J, Albers GW, Lansberg MG, Kastrup A, Rovira A, Liebeskind DS, Gass A, Rosso C, Derex L, Kim JS, Neumann-Haefelin T. Risk of symptomatic intracerebral hemorrhage in patients treated with intra-arterial thrombolysis. Cerebrovasc Dis 2009; 27:368-74. [PMID: 19218803 DOI: 10.1159/000202427] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2008] [Accepted: 11/25/2008] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND In intra-arterial (IA) thrombolysis trials, higher rates of symptomatic intracerebral haemorrhage (sICH) were found than in trials with intravenous (IV) recombinant tissue plasminogen activator (tPA); this observation could have been due to the inclusion of more severely affected patients in IA thrombolysis trials. In the present study, we investigated the rate of sICH in IA and combined IV + IA thrombolysis versus IV thrombolysis after adjusting for differences in clinical and MRI parameters. METHODS In this multicenter study, we systematically analyzed data from 645 patients with anterior-circulation strokes treated with either IV or IA thrombolysis within 6 h following symptom onset. Thrombolytic regimens included (1) IV tPA treatment (n = 536) and (2) IA treatment with either tPA or urokinase (n = 74) or (3) combined IV + IA treatment with either tPA or urokinase (n = 35). RESULTS 44 (6.8%) patients developed sICH. sICH patients had significantly higher scores on the National Institutes of Health Stroke Scale (NIHSS) at admission and pretreatment DWI lesions. The sICH risk was 5.2% (n = 28) in IV thrombolysis, which is significantly lower than in IA (12.5%, n = 9) or IV + IA thrombolysis (20%, n = 7). In a binary logistic regression analysis including age, NIHSS score, time to thrombolysis, initial diffusion weighted imaging lesion size, mode of thrombolytic treatment and thrombolytic agent, the mode of thrombolytic treatment remained an independent predictor for sICH. The odds ratio for IA or IV + IA versus IV treatment was 3.466 (1.19-10.01, 95% CI, p < 0.05). CONCLUSION In this series, IA and IV + IA thrombolysis is associated with an increased sICH risk as compared to IV thrombolysis, and this risk is independent of differences in baseline parameters such as age, initial NIHSS score or pretreatment lesion size.
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Affiliation(s)
- O C Singer
- Klinik für Neurologie, Goethe-Universität, Frankfurt, Germany.
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128
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Schlaganfall-MRT zur Abschätzung des Blutungsrisikos bei thrombolytischer Therapie. DER NERVENARZT 2009; 80:130, 132-6. [DOI: 10.1007/s00115-008-2593-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Imaging blood-brain barrier disruption: an evolving tool for assessing the risk of hemorrhage after thrombolysis. ACTA ACUST UNITED AC 2008; 4:644-5. [PMID: 18941429 DOI: 10.1038/ncpneuro0935] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2008] [Accepted: 09/05/2008] [Indexed: 11/09/2022]
Abstract
This Practice Point commentary discusses a study by Kastrup et al. that demonstrates that the early detection of blood-brain barrier (BBB) disruption as detected on post-contrast enhanced T1-weighted MRI after thrombolysis for acute ischemic stroke predicts subsequent intracerebral hemorrhage. No parenchymal enhancements were detected on scans before thrombolysis; however, after thrombolysis, 3 of 48 patients had parenchymal enhancement in the areas of the initial insult and these patients later developed symptomatic hemorrhages at these sites. These data suggest that assessment of BBB integrity might be a useful addition to a multimodal MRI study, potentially improving the overall efficacy of thrombolysis and broadening the effective time window. Further work is needed to optimize an imaging sequence that will be short and sufficiently sensitive to detect early damage to the BBB before treatment. Meanwhile, prudent clinicians should select patients for therapy on the basis of accepted guidelines and best clinical judgment.
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Abstract
PURPOSE OF REVIEW The aim of this article is to review the latest clinical trials in neurological diseases where magnetic resonance imaging was used to assess treatment outcome. RECENT FINDINGS The unique sensitivity of magnetic resonance imaging for detecting disorders in the brain has made it an attractive noninvasive tool for assessing treatment efficacy in several diseases. Volumetric and functional magnetic resonance imaging have proved to represent robust biomarkers for the evaluation of anti-Alzheimer treatments, and have demonstrated a significant impact of cholinesterase inhibitors. The optimization of thrombolytic therapy in acute ischemic stroke has concentrated on the quantification of the ischemic penumbra, using perfusion-weighted and diffusion-weighted imaging. Standard assessment of T2 or fluid-attenuated inversion recovery lesion load remains the method of choice to evaluate new therapeutic strategy in multiple sclerosis. Other nonconventional quantitative magnetic resonance imaging techniques such as magnetic resonance volumetry, magnetization transfer imaging, diffusion-weighted imaging, or magnetic resonance spectroscopy are increasingly used in the field. SUMMARY Magnetic resonance imaging has become a major surrogate marker of treatment response in clinical trials of neurological disorders, offering the possibility to reduce the required sample size or to shorten the duration of the trial.
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Affiliation(s)
- Carolina Ciumas
- CTRS-INSERM IDEE (Institut Des Epilepsies de l'Enfant et de l'adolescent), INSERM U821, CERMEP imagerie du vivant, and Department of Functional Neurology and Epileptology, Hospices Civils de Lyon and Université Claude Bernard Lyon 1, Lyon, France
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Affiliation(s)
| | - Martin Köhrmann
- From the Department of Neurology, University at Erlangen, Erlangen, Germany
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Hsia AW, Kidwell CS. Developments in neuroimaging for acute ischemic stroke: diagnostic and clinical trial applications. Curr Atheroscler Rep 2008; 10:339-46. [PMID: 18606105 DOI: 10.1007/s11883-008-0052-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Over the past several years, active investigation into neuroimaging in the setting of acute ischemic stroke has improved our understanding of and ability to visualize the dynamic pathophysiology of acute cerebrovascular disease. Efforts surrounding the application of multimodal CT and MRI have resulted in a growing body of data from systematic evaluations of different parameters, experience in the use of these techniques in guiding clinical decision making, and clinical trials employing neuroimaging for patient selection, for proof of principle, and as a surrogate outcome measure.
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Affiliation(s)
- Amie W Hsia
- Washington Hospital Center, Stroke Center, Washington, DC, USA.
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Lövblad KO, Altrichter S, Viallon M, Sztajzel R, Delavelle J, Vargas MI, El-Koussy M, Federspiel A, Sekoranja L. Neuro-imaging of cerebral ischemic stroke. J Neuroradiol 2008; 35:197-209. [PMID: 18329713 DOI: 10.1016/j.neurad.2008.01.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Major progress has recently been made in the neuro-imaging of stroke as a result of improvements in imaging hardware and software. Imaging may be based on either magnetic resonance imaging (MRI) or computed tomography (CT) techniques. Imaging should provide information on the entire vascular cervical and intracranial network, from the aortic arch to the circle of Willis. Equally, it should also give information on the viability of brain tissue and brain hemodynamics. CT has the advantage in the detection of acute hemorrhage whereas MRI offers more accurate pathophysiological information in the follow-up of patients.
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Affiliation(s)
- K O Lövblad
- Unité de neuroradiologie, service de radiologie, DISIM, hôpitaux universitaires de Genève, 24, rue Micheli-du-Crest, 1211 Genève 4, Switzerland.
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134
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Affiliation(s)
- A Gregory Sorensen
- Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
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