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Irvine HJ, Ostwaldt AC, Bevers MB, Dixon S, Battey TW, Campbell BC, Davis SM, Donnan GA, Sheth KN, Jahan R, Saver JL, Kidwell CS, Kimberly WT. Reperfusion after ischemic stroke is associated with reduced brain edema. J Cereb Blood Flow Metab 2018; 38:1807-1817. [PMID: 28731381 PMCID: PMC6168909 DOI: 10.1177/0271678x17720559] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Rapid revascularization is highly effective for acute stroke, but animal studies suggest that reperfusion edema may attenuate its beneficial effects. We investigated the relationship between reperfusion and edema in patients from the Echoplanar Imaging Thrombolysis Evaluation Trial (EPITHET) and Mechanical Retrieval and Recanalization of Stroke Clots Using Embolectomy (MR RESCUE) cohorts. Reperfusion percentage was measured as the difference in perfusion-weighted imaging lesion volume between baseline and follow-up (day 3-5 for EPITHET; day 6-8 for MR RESCUE). Midline shift (MLS) and swelling volume were quantified on follow-up MRI. We found that reperfusion was associated with less MLS (EPITHET: Spearman ρ = -0.46; P < 0.001, and MR RESCUE: Spearman ρ = -0.49; P < 0.001) and lower swelling volume (EPITHET: Spearman ρ = -0.56; P < 0.001, and MR RESCUE: Spearman ρ = -0.27; P = 0.026). Multivariable analyses performed in EPITHET and MR RESCUE demonstrated that reperfusion independently predicted both less MLS (ß coefficient = -0.056; P = 0.025, and ß coefficient = -0.38; P = 0.028, respectively) and lower swelling volumes (ß coefficient = -4.7; P = 0.007, and ß coefficient = -10.7; P = 0.009, respectively), after adjusting for age, sex, NIHSS, admission glucose and follow-up lesion size. Taken together, our data suggest that even modest improvement in perfusion is associated with less brain edema in EPITHET and MR RESCUE.
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Affiliation(s)
- Hannah J Irvine
- 1 Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA.,2 Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital, Boston, MA, USA
| | - Ann-Christin Ostwaldt
- 1 Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA.,2 Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital, Boston, MA, USA
| | - Matthew B Bevers
- 3 Divisions of Stroke, Cerebrovascular and Critical Care Neurology, Brigham & Women's Hospital, Boston, MA, USA
| | - Simone Dixon
- 4 Department of Neurology, University of Arizona College of Medicine, Tucson, AZ, USA
| | - Thomas Wk Battey
- 1 Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA.,2 Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital, Boston, MA, USA
| | - Bruce Cv Campbell
- 5 Department of Medicine and Neurology, Melbourne Brain Centre at the Royal Melbourne Hospital, University of Melbourne, Parkville, Victoria, Australia.,6 Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Stephen M Davis
- 5 Department of Medicine and Neurology, Melbourne Brain Centre at the Royal Melbourne Hospital, University of Melbourne, Parkville, Victoria, Australia
| | - Geoffrey A Donnan
- 6 Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Kevin N Sheth
- 7 Division of Neurocritical Care and Emergency Neurology, Yale New Haven Hospital, New Haven, USA
| | - Reza Jahan
- 8 Department of Radiology, Ronald Reagan - UCLA Medical Center, Los Angeles, CA, USA
| | - Jeffrey L Saver
- 9 Comprehensive Stroke Center and Department of Neurology, Ronald Reagan - UCLA Medical Center, Los Angeles, CA, USA
| | - Chelsea S Kidwell
- 4 Department of Neurology, University of Arizona College of Medicine, Tucson, AZ, USA
| | - W Taylor Kimberly
- 1 Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA.,2 Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital, Boston, MA, USA
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2
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Yu S, Ma SJ, Liebeskind DS, Yu D, Li N, Qiao XJ, Shao X, Yan L, Yoo B, Scalzo F, Hinman JD, Sharma LK, Rao N, Jahan R, Tateshima S, Duckwiler GR, Saver JL, Salamon N, Wang DJ. ASPECTS-based reperfusion status on arterial spin labeling is associated with clinical outcome in acute ischemic stroke patients. J Cereb Blood Flow Metab 2018; 38:382-392. [PMID: 28266894 PMCID: PMC5851135 DOI: 10.1177/0271678x17697339] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The purpose of this study was to develop and evaluate a scoring system for assessing reperfusion status based on arterial spin labeled (ASL) perfusion MRI in acute ischemic stroke (AIS) patients receiving thrombolysis and/or endovascular treatment. Pseudo-continuous ASL with background suppressed 3D GRASE was acquired along with DWI in 90 patients within 24 h post-treatment. An automatic reperfusion scoring system (auto-RPS) was devised based on the Alberta Stroke Program Early CT Score (ASPECTS) template, and compared with manual RPS and DWI-ASPECTS. TICI (thrombolysis in cerebral infarction) scores were graded in 48 patients who received endovascular treatment. Favorable outcomes were defined by a modified Rankin Scale score of 0-2 at three months. Auto-RPS was positively correlated with DWI-ASPECTS (ρ = 0.6, P < 0.001) and was on average 1 point lower than DWI-ASPECTS ( P < 0.001). The area under the receiver operating characteristic curve for discriminating poor functional outcome (n = 90) was 0.75 (95% CI, 0.64-0.86) for manual RPS, 0.85 (95% CI, 0.76-0.94) for auto-RPS, and 0.81 (95% CI, 0.71-0.90) for DWI-ASPECTS. Multiple logistic regression analysis in the TICI-graded patients (n = 48) showed that auto-RPS is highly associated with functional outcome (OR = 25.2, 95% CI 4.02-496, P < 0.01). Post treatment auto-RPS within 24 h provides a useful tool to predict functional outcome in AIS patients.
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Affiliation(s)
- Songlin Yu
- 1 Department of Neurology, UCLA, Los Angeles, CA, USA.,2 Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Samantha J Ma
- 3 Stevens Neuroimaging and Informatics Institute, Department of Neurology, University of Southern California, CA, USA
| | - David S Liebeskind
- 4 Neurovascular Imaging Research Core and Department of Neurology, UCLA, Los Angeles, CA, USA
| | - Dandan Yu
- 5 Neuro-Intensive Care Unit, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Ning Li
- 6 Department of Biomathematics, UCLA, Los Angeles, CA, USA
| | - Xin J Qiao
- 7 Department of Radiology, UCLA, Los Angeles, CA, USA
| | - Xingfeng Shao
- 3 Stevens Neuroimaging and Informatics Institute, Department of Neurology, University of Southern California, CA, USA
| | - Lirong Yan
- 3 Stevens Neuroimaging and Informatics Institute, Department of Neurology, University of Southern California, CA, USA
| | - Bryan Yoo
- 7 Department of Radiology, UCLA, Los Angeles, CA, USA
| | - Fabien Scalzo
- 4 Neurovascular Imaging Research Core and Department of Neurology, UCLA, Los Angeles, CA, USA
| | | | | | - Neal Rao
- 1 Department of Neurology, UCLA, Los Angeles, CA, USA
| | - Reza Jahan
- 8 Division of Interventional Neuroradiology and Stroke Center, UCLA, Los Angeles, CA, USA
| | - Satoshi Tateshima
- 2 Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Gary R Duckwiler
- 8 Division of Interventional Neuroradiology and Stroke Center, UCLA, Los Angeles, CA, USA
| | | | | | - Danny Jj Wang
- 1 Department of Neurology, UCLA, Los Angeles, CA, USA.,3 Stevens Neuroimaging and Informatics Institute, Department of Neurology, University of Southern California, CA, USA
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3
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Irvine HJ, Battey TW, Ostwaldt AC, Campbell BC, Davis SM, Donnan GA, Sheth KN, Kimberly WT. Early neurological stability predicts adverse outcome after acute ischemic stroke. Int J Stroke 2016; 11:882-889. [PMID: 27334760 DOI: 10.1177/1747493016654484] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Background Deterioration in the National Institutes of Health Stroke Scale (NIHSS) in the early days after stroke is associated with progressive infarction, brain edema, and/or hemorrhage, leading to worse outcome. Aims We sought to determine whether a stable NIHSS score represents an adverse or favorable course. Methods Brain magnetic resonance images from a research cohort of acute ischemic stroke patients were analyzed. Using NIHSS scores at baseline and follow-up (day 3-5), patients were categorized into early neurological deterioration (ΔNIHSS ≥ 4), early neurological recovery (ΔNIHSS ≤ -4) or early neurological stability (ΔNIHSS between -3 and 3). The association between these categories and volume of infarct growth, volume of swelling, parenchymal hemorrhage, and 3-month modified Rankin Scale score were evaluated. Results Patients with early neurological deterioration or early neurological stability were less likely to be independent (modified Rankin Scale = 0-2) at 3 months compared to those with early neurological recovery ( P < 0.001). Patients with early neurological deterioration or early neurological stability were observed to have significantly greater infarct growth and swelling volumes than those with early neurological recovery ( P = 0.03; P < 0.001, respectively). Brain edema was more common than the other imaging markers investigated and was independently associated with a stable or worsening NIHSS score after adjustment for age, baseline stroke volume, infarct growth volume, presence of parenchymal hemorrhage, and reperfusion ( P < 0.0001). Conclusions Stable NIHSS score in the subacute period after ischemic stroke may not be benign and is associated with tissue injury, including infarct growth and brain edema. Early improvement is considerably more likely to occur in the absence of these factors.
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Affiliation(s)
- Hannah J Irvine
- 1 Center for Human Genetic Research and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital, Boston, USA
| | - Thomas Wk Battey
- 1 Center for Human Genetic Research and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital, Boston, USA
| | - Ann-Christin Ostwaldt
- 1 Center for Human Genetic Research and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital, Boston, USA
| | - Bruce Cv Campbell
- 2 Department of Medicine and Neurology, University of Melbourne, Parkville, Australia.,3 Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia
| | - Stephen M Davis
- 2 Department of Medicine and Neurology, University of Melbourne, Parkville, Australia
| | - Geoffrey A Donnan
- 3 Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia
| | - Kevin N Sheth
- 4 Division of Neurocritical Care and Emergency Neurology, Yale New Haven Hospital, New Haven, USA
| | - W Taylor Kimberly
- 1 Center for Human Genetic Research and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital, Boston, USA.,5 J. Philip Kistler Stroke Research Center, Massachusetts General Hospital, Boston, USA
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Abstract
INTRODUCTION Acute ischemic stroke (AIS) is one of the leading causes of mortality and adult disability worldwide. For two decades, the preferred approach for AIS was intravenous recombinant tissue plasminogen activator (IV tPA). However, IV tPA cannot be given to many AIS patients who do not meet strict criteria for its use. IV tPA has also had lesser benefit in patients with large clot burden in the context of large vessel occlusion (LVO). AREAS COVERED Endovascular stroke therapy had been an 'unproven' therapy despite numerous trials of intra-arterial pharmacologic thrombolysis and mechanical thrombectomy. With the advent of stent-retriever devices, there has been a paradigm shift in the utilization of endovascular therapies for AIS. Our review discusses cerebrovascular hemodynamics, the basis of the recanalization models in AIS, aspects of intravenous thrombolysis, prior generations of endovascular therapy, and the recent successful AIS stent retriever trials. Expert commentary: Recently 'stent-retrievers', a new generation of mechanical thrombectomy devices, were shown to be associated with improved functional outcomes in AIS secondary to proximal intracranial anterior circulation LVO. Stent retrievers are a major advance in AIS care and will have significant impact on the evolution of stroke systems of care.
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Affiliation(s)
- Rick Gill
- a Department of Neurology , Loyola University Chicago - Stritch School of Medicine , Maywood , IL , USA
| | - Michael J Schneck
- a Department of Neurology , Loyola University Chicago - Stritch School of Medicine , Maywood , IL , USA.,b Department of Neurological Surgery , Loyola University Chicago - Stritch School of Medicine , Maywood , IL , USA
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5
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Kim BJ, Han MK, Park TH, Park SS, Lee KB, Lee BC, Yu KH, Oh MS, Cha JK, Kim DH, Lee J, Lee SJ, Ko Y, Park JM, Kang K, Cho YJ, Hong KS, Kim JT, Choi JC, Kim DE, Lee J, Lee JS, Gorelick PB, Yoon BW, Bae HJ. Trends in the Effectiveness of Endovascular Recanalization for Acute Stroke: Is a Change Taking Place? J Stroke Cerebrovasc Dis 2015; 24:866-73. [DOI: 10.1016/j.jstrokecerebrovasdis.2014.12.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Revised: 11/24/2014] [Accepted: 12/03/2014] [Indexed: 11/29/2022] Open
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6
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Reversing the deleterious effects of α2-antiplasmin on tissue plasminogen activator therapy improves outcomes in experimental ischemic stroke. Exp Neurol 2014; 255:56-62. [PMID: 24556477 DOI: 10.1016/j.expneurol.2014.02.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 01/17/2014] [Accepted: 02/07/2014] [Indexed: 12/20/2022]
Abstract
High blood levels of α2-antiplasmin have been associated with failed tissue plasminogen activator (TPA) therapy for ischemic stroke. Yet, other data suggests that α2-antiplasmin may be protective in stroke, because it defends against bleeding and excitotoxicity. To address this paradox, we examined the effects of high α2-antiplasmin levels and α2-antiplasmin inactivation in mice treated with TPA 0.5-2.5h after middle cerebral artery (MCA) thromboembolism. Brain infarction, swelling, hemorrhage, blood brain barrier breakdown and neuronal apoptosis were measured by a blinded observer. Thrombus dissolution was determined by gamma counting. During TPA treatment, high α2-antiplasmin blood levels increased brain infarction (2.2-fold) and swelling (3.7-fold), but decreased MCA thrombus dissolution. Conversely, α2-antiplasmin inactivation during TPA treatment reduced brain infarction, hemorrhage and swelling, but increased MCA thrombus dissolution. Inactivation of α2-antiplasmin during TPA treatment reduced neuronal apoptosis and blood brain barrier breakdown. Inactivation of α2-antiplasmin also reduced short-term mortality. Taken together these data show that α2-antiplasmin opposes the effects of TPA therapy and contributes to enhanced brain injury after experimental thromboembolic stroke. Conversely, α2-antiplasmin inactivation during TPA treatment improves thrombus dissolution and reduces brain infarction, swelling and hemorrhage. Consistent with clinical observations, these data suggest that α2-antiplasmin exerts deleterious effects that reduce the efficacy and safety of TPA therapy for ischemic stroke.
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Eilaghi A, Brooks J, d'Esterre C, Zhang L, Swartz RH, Lee TY, Aviv RI. Reperfusion Is a Stronger Predictor of Good Clinical Outcome than Recanalization in Ischemic Stroke. Radiology 2013; 269:240-8. [PMID: 23716707 DOI: 10.1148/radiol.13122327] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Armin Eilaghi
- Robarts Research Institute, University of Western Ontario, London, Ont, Canada; Department of Medical Imaging, Odette Cancer Centre, and Department of Medicine, Sunnybrook Health Sciences Centre, University of Toronto, 2075 Bayview Ave, Toronto, ON, Canada M4N 3M5
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8
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Abstract
Appropriate acute treatment with plasminogen activators (PAs) can significantly increase the probability of minimal or no disability in selected ischemic stroke patients. There is a great deal of evidence showing that intravenous recombinant tissue PAs (rt-PA) infusion accomplishes this goal, recanalization with other PAs has also been demonstrated in the development of this treatment. Recanalization of symptomatic, documented carotid or vertebrobasilar arterial territory occlusions have also been achieved by local intra-arterial PA delivery, although only a single prospective double-blinded randomized placebo-controlled study has been reported. The increase in intracerebral hemorrhage with these agents by either delivery approach underscores the need for careful patient selection, dose-appropriate safety and efficacy, proper clinical trial design, and an understanding of the evolution of cerebral tissue injury due to focal ischemia. Principles underlying the evolution of focal ischemia have been expanded by experience with acute PA intervention. Several questions remain open that concern the manner in which PAs can be applied acutely in ischemic stroke and how injury development can be limited.
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Affiliation(s)
- Gregory J del Zoppo
- Division of Hematology, Department of Medicine, University of Washington School of Medicine, Seattle, Washington 98104, USA.
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9
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Machumpurath B, Reddy M, Yan B. Rapid Neurological Recovery Post Thrombolysis: Mechanisms and Implications. ACTA ACUST UNITED AC 2013. [DOI: 10.4236/nm.2013.41006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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10
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Abstract
Thrombus formation is of paramount importance in the pathophysiology of acute ischemic stroke. Current antithrombotics used to treat or prevent cerebral ischemia are only moderately effective or bear an increased risk of severe bleeding. von Willebrand factor (VWF) has long been known to be a key player in thrombus formation at sites of vascular damage. While the association between VWF and coronary heart disease has been well studied, knowledge about the role of VWF in stroke is much more limited. However, in recent years, an increasing amount of clinical and preclinical evidence has revealed the critical involvement of VWF in stroke development. This review summarizes the latest insights into the pathophysiologic role of VWF-related processes in ischemic brain injury under experimental conditions and in humans. Potential clinical merits of novel inhibitors of VWF-mediated platelet adhesion and activation as powerful and safe tools to combat thromboembolic disorders including ischemic stroke are discussed. Preclinical and clinical evidence illustrates an important role of VWF in ischemic stroke, suggesting that VWF could become a promising target in stroke therapy.
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Affiliation(s)
- Simon F De Meyer
- Immune Disease Institute, Children's Hospital Boston, Boston, MA, USA.
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11
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Mikulik R, Dusek L, Hill MD, Fulep E, Grotta JC, Ribo M, Molina C, Alexandrov AV. Pattern of response of National Institutes of Health Stroke Scale components to early recanalization in the CLOTBUST trial. Stroke 2010; 41:466-70. [PMID: 20133918 DOI: 10.1161/strokeaha.109.567263] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Early recanalization is the likely mechanism by which intravenous thrombolysis improves stroke outcomes. Limited data exist on the patterns of early recovery of various brain functions. METHODS Data from the Combined Lysis of Thrombus in Brain Ischemia Using Transcranial Ultrasound and Systemic t-PA (CLOTBUST) trial was used to determine time-related trends in neurological function recovery, as measured by National Institutes of Health Stroke Scale (NIHSS) components at baseline, 30, 60, 90, 120 minutes, and 24 hours. Repeated-measures ANOVA was used to compare patients with complete recanalization versus no or partial recanalization of the middle cerebral artery (MCA) at 120 minutes from tissue plasminogen activator bolus. The correlation structure of the NIHSS was analyzed with multivariable factor analysis. The ability of individual components to diagnose recanalization was assessed with area under the receiver operating characteristic curves. RESULTS Altogether, 113 patients from the CLOTBUST trial had complete follow-up NIHSS scores available. All received 0.9 mg/kg IV tissue plasminogen activator within 3 hours of symptom onset (mean age 69+/-12 years; 58% men; median NIHSS 16; complete MCA recanalization 27%). All NIHSS components attributable to MCA occlusion contributed with varying degrees to the decrease of the total NIHSS score after MCA recanalization. NIHSS components responded in 2 major and mutually independent clusters representing left and right brain functions. The best performing component in diagnosing recanalization was gaze deviation (area under the receiver operating characteristic curve=0.80), but its results were similar to the total NIHSS score (area under the receiver operating characteristic curve=0.75). CONCLUSIONS All neurological functions, impaired because of MCA occlusion, recovered after recanalization, although not to the same extent. The total NIHSS score is more useful than the individual components in detecting MCA recanalization.
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Affiliation(s)
- Robert Mikulik
- Department of Neurology, Masaryk University, St Anne's University Hospital, Pekarská 53, 656 91 Brno, Czech Republic.
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12
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Soares BP, Tong E, Hom J, Cheng SC, Bredno J, Boussel L, Smith WS, Wintermark M. Reperfusion is a more accurate predictor of follow-up infarct volume than recanalization: a proof of concept using CT in acute ischemic stroke patients. Stroke 2009; 41:e34-40. [PMID: 19910542 DOI: 10.1161/strokeaha.109.568766] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE The purpose of this study was to compare recanalization and reperfusion in terms of their predictive value for imaging outcomes (follow-up infarct volume, infarct growth, salvaged penumbra) and clinical outcome in acute ischemic stroke patients. MATERIAL AND METHODS Twenty-two patients admitted within 6 hours of stroke onset were retrospectively included in this study. These patients underwent a first stroke CT protocol including CT-angiography (CTA) and perfusion-CT (PCT) on admission, and similar imaging after treatment, typically around 24 hours, to assess recanalization and reperfusion. Recanalization was assessed by comparing arterial patency on admission and posttreatment CTAs; reperfusion, by comparing the volumes of CBV, CBF, and MTT abnormality on admission and posttreatment PCTs. Collateral flow was graded on the admission CTA. Follow-up infarct volume was measured on the discharge noncontrast CT. The groups of patients with reperfusion, no reperfusion, recanalization, and no recanalization were compared in terms of imaging and clinical outcomes. RESULTS Reperfusion (using an MTT reperfusion index >75%) was a more accurate predictor of follow-up infarct volume than recanalization. Collateral flow and recanalization were not accurate predictors of follow-up infarct volume. An interaction term was found between reperfusion and the volume of the admission penumbra >50 mL. CONCLUSIONS Our study provides evidence that reperfusion is a more accurate predictor of follow-up infarct volume in acute ischemic stroke patients than recanalization. We recommend an MTT reperfusion index >75% to assess therapy efficacy in future acute ischemic stroke trials that use perfusion-CT.
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Affiliation(s)
- Bruno P Soares
- Department of Radiology, Neuroradiology Section, University of California, San Francisco, 505 Parnassus Avenue, Box 0628, San Francisco, CA 94143-0628, USA
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