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Wegener S, Baron JC, Derdeyn CP, Fierstra J, Fromm A, Klijn CJM, van Niftrik CHB, Schaafsma JD. Hemodynamic Stroke: Emerging Concepts, Risk Estimation, and Treatment. Stroke 2024; 55:1940-1950. [PMID: 38864227 DOI: 10.1161/strokeaha.123.044386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2024]
Abstract
Ischemic stroke can arise from the sudden occlusion of a brain-feeding artery by a clot (embolic), or local thrombosis. Hemodynamic stroke occurs when blood flow does not sufficiently meet the metabolic demand of a brain region at a certain time. This discrepancy between demand and supply can occur with cerebropetal arterial occlusion or high-grade stenosis but also arises with systemic conditions reducing blood pressure. Treatment of hemodynamic stroke is targeted toward increasing blood flow to the affected area by either systemically or locally enhancing perfusion. Thus, blood pressure is often maintained above normal values, and extra-intracranial flow augmentation bypass surgery is increasingly considered. Still, current evidence supporting the superiority of pressure or flow increase over conservative measures is limited. However, methods assessing hemodynamic impairment and identifying patients at risk of hemodynamic stroke are rapidly evolving. Sophisticated models incorporating clinical and imaging factors have been suggested to aid patient selection. In this narrative review, we provide current state-of-the-art knowledge about hemodynamic stroke, tools for assessment, and treatment options.
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Affiliation(s)
- Susanne Wegener
- Department of Neurology (S.W.), University Hospital Zurich (USZ) and University of Zurich (UZH), Switzerland
- Clinical Neurocenter Zurich and Neuroscience Center Zurich (ZNZ), Switzerland (S.W., J.F., C.H.B.v.N.)
| | - Jean Claude Baron
- Department of Neurology, GHU Paris Psychiatrie et Neurosciences, Hôpital Sainte-Anne, Université Paris Cité, Inserm U1266, FHU NeuroVasc, France (J.C.B.)
| | - Colin P Derdeyn
- Department of Radiology and Medical Imaging, University of Virginia School of Medicine, Charlottesville (C.P.D.)
| | - Jorn Fierstra
- Department of Neurosurgery (J.F., C.H.B.v.N.), University Hospital Zurich (USZ) and University of Zurich (UZH), Switzerland
- Clinical Neurocenter Zurich and Neuroscience Center Zurich (ZNZ), Switzerland (S.W., J.F., C.H.B.v.N.)
| | - Annette Fromm
- Department of Neurology, Haukeland University Hospital, Bergen, Norway (A.F.)
| | - Catharina J M Klijn
- Department of Neurology at Radboud University Nijmegen, the Netherlands (C.J.M.K.)
| | - Christiaan Hendrik Bas van Niftrik
- Department of Neurosurgery (J.F., C.H.B.v.N.), University Hospital Zurich (USZ) and University of Zurich (UZH), Switzerland
- Clinical Neurocenter Zurich and Neuroscience Center Zurich (ZNZ), Switzerland (S.W., J.F., C.H.B.v.N.)
| | - Joanna D Schaafsma
- Division of Neurology, Department of Medicine (JDS) and Division of Neuroradiology, Department of Medical Imaging, University Health Network, Toronto, Canada (DJM, DMM) (J.D.S.)
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Baron JC. Predicting Stroke Recurrence in Occlusive Disease Using Noninvasive Quantitative Mapping of Cerebrovascular Reserve. Stroke 2024; 55:622-624. [PMID: 38328925 DOI: 10.1161/strokeaha.124.046235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Affiliation(s)
- Jean-Claude Baron
- Department of Neurology, Hôpital Sainte-Anne, GHU Paris Psychiatrie et Neurosciences, FHU NeuroVasc, France. Université Paris Cité, Institut de Psychiatrie et Neurosciences de Paris, Inserm U1266, France
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Shang J, Dong J, Zhu S, Chen Q, Hua J. Trends in cognitive function before and after myocardial infarction: findings from the China Health and Retirement Longitudinal Study. Front Aging Neurosci 2024; 16:1283997. [PMID: 38455665 PMCID: PMC10917921 DOI: 10.3389/fnagi.2024.1283997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Accepted: 02/05/2024] [Indexed: 03/09/2024] Open
Abstract
Objectives Incident stroke was associated with cognitive dysfunction after stroke and even before stroke. However, cognitive trends prior to myocardial infarction (MI) and the timeline of cognitive decline in a few years following incident MI remain unclear, especially among the Chinese population. We aimed to evaluate whether MI was associated with cognitive change both before and after MI in China. Methods This cohort study included 11,287 participants without baseline heart problems or stroke from the China Health and Retirement Longitudinal Study. The exposure was self-reported MI. The outcomes were scores of cognitive functions in five domains, which reflected abilities of episodic memory, visuospatial abilities, orientation, attention and calculation, and global cognition as a summary measure. A Linear mixed model was constructed to explore cognitive function before and after incident MI among the MI participants and the cognitive trends of participants free of MI. Results During the 7-year follow-up, 421 individuals [3.7% of 11,287, mean (SD) age, 60.0 (9.0) years; 59.1% female] experienced MI events. The cognitive scores of participants of both the MI group and the control group without MI declined gradually as time went by. The annual decline rate of the MI group before incident MI was similar to that of the control group during the whole follow-up period. Incident MI was not associated with acute cognitive decline in all five cognitive domains. Moreover, MI did not accelerate the cognitive decline rate after MI compared with the pre-MI cognitive trends. The decline rate of cognitive function after MI was similar to the rate before MI. Conclusions Different from stroke, participants who had an MI did not show steeper cognitive decline before MI. MI was not associated with acute cognitive decline and accelerated decline in several years after MI. Future studies are needed to learn the mechanisms behind the different patterns of cognitive decline between MI and stroke.
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Affiliation(s)
- Jing Shang
- Department of Psychiatry, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Jianye Dong
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Sijia Zhu
- Department of Neurology, The Fourth Affiliated Hospital of Soochow University, Medical Center of Soochow University, Suzhou Dushu Lake Hospital, Suzhou, Jiangsu, China
| | - Qingmei Chen
- Department of Physical Medicine and Rehabilitation, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Jianian Hua
- Department of Neurology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
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Gatti JR, Ahmad SA, Gardner Yelton S, DiGiusto M, Leung D, Xu R, Cohen AR, Gottesman RF, Sun LR. Relative anemia and perioperative stroke in children with moyamoya. J Stroke Cerebrovasc Dis 2024; 33:107476. [PMID: 37976795 PMCID: PMC10842685 DOI: 10.1016/j.jstrokecerebrovasdis.2023.107476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 10/13/2023] [Accepted: 11/06/2023] [Indexed: 11/19/2023] Open
Abstract
OBJECTIVES Surgical revascularization for moyamoya arteriopathy decreases long-term stroke risk but carries a risk of perioperative ischemic complications. We aimed to evaluate modifiable stroke risk factors in children undergoing surgical revascularization for moyamoya. MATERIALS AND METHODS In this exploratory, single-center, retrospective cohort study, medical records of pediatric patients undergoing surgical revascularization for moyamoya arteriopathy at our center between 2003 and 2021 were reviewed. Candidate modifiable risk factors were analyzed for association with perioperative stroke, defined as ischemic stroke ≤7 days after surgery. RESULTS We analyzed 53 surgeries, consisting of 39 individual patients undergoing indirect surgical revascularization of 74 hemispheres. Perioperative ischemic stroke occurred following five surgeries (9.4%). There were no instances of hemorrhagic stroke. Larger pre-to-postoperative decreases in hemoglobin (OR 3.90, p=0.017), hematocrit (OR 1.69, p=0.012) and blood urea nitrogen (OR 1.83, p=0.010) were associated with increased risk of perioperative ischemic stroke. Weight-adjusted intraoperative blood loss was not associated with risk of perioperative ischemic stroke (OR 0.94, p=0.796). Among children with sickle cell disease, all of whom underwent exchange transfusion within one week prior to surgery, none experienced perioperative stroke. CONCLUSIONS Decreases in hemoglobin, hematocrit, and blood urea nitrogen between the preoperative and postoperative periods are associated with increased risk of perioperative stroke. These novel findings suggest that dilutional anemia, possibly due to standardly administered hyperhydration, may increase the risk of perioperative stroke in some children with moyamoya. Further work optimizing both mean arterial pressure and oxygen-carrying capacity in these patients, including consideration of alternative blood transfusion thresholds, is necessary.
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Affiliation(s)
- John R Gatti
- Johns Hopkins School of Medicine, Baltimore, MD, USA
| | | | - Sarah Gardner Yelton
- Division of Pediatric Cardiology, Ann and Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA
| | - Matthew DiGiusto
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Dennis Leung
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Risheng Xu
- Department of Neurosurgery, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Alan R Cohen
- Department of Neurosurgery, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Rebecca F Gottesman
- National Institute of Neurological Disease and Stroke Intramural Research Program, Bethesda, MD, USA
| | - Lisa R Sun
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA.
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Sebök M, van der Wouden F, Mader C, Pangalu A, Treyer V, Fisher JA, Mikulis DJ, Hüllner M, Regli L, Fierstra J, van Niftrik CHB. Hemodynamic Failure Staging With Blood Oxygenation Level-Dependent Cerebrovascular Reactivity and Acetazolamide-Challenged ( 15O-)H 2O-Positron Emission Tomography Across Individual Cerebrovascular Territories. J Am Heart Assoc 2023; 12:e029491. [PMID: 38084716 PMCID: PMC10863778 DOI: 10.1161/jaha.123.029491] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 09/11/2023] [Indexed: 12/20/2023]
Abstract
BACKGROUND Staging of hemodynamic failure (HF) in symptomatic patients with cerebrovascular steno-occlusive disease is required to assess the risk of ischemic stroke. Since the gold standard positron emission tomography-based perfusion reserve is unsuitable as a routine clinical imaging tool, blood oxygenation level-dependent cerebrovascular reactivity (BOLD-CVR) with CO2 is a promising surrogate imaging approach. We investigated the accuracy of standardized BOLD-CVR to classify the extent of HF. METHODS AND RESULTS Patients with symptomatic unilateral cerebrovascular steno-occlusive disease, who underwent both an acetazolamide challenge (15O-)H2O-positron emission tomography and BOLD-CVR examination, were included. HF staging of vascular territories was assessed using qualitative inspection of the positron emission tomography perfusion reserve images. The optimum BOLD-CVR cutoff points between HF stages 0-1-2 were determined by comparing the quantitative BOLD-CVR data to the qualitative (15O-)H2O-positron emission tomography classification using the 3-dimensional accuracy index to the randomly assigned training and test data sets with the following determination of a single cutoff for clinical application. In the 2-case scenario, classifying data points as HF 0 or 1-2 and HF 0-1 or 2, BOLD-CVR showed an accuracy of >0.7 for all vascular territories for HF 1 and HF 2 cutoff points. In particular, the middle cerebral artery territory had an accuracy of 0.79 for HF 1 and 0.83 for HF 2, whereas the anterior cerebral artery had an accuracy of 0.78 for HF 1 and 0.82 for HF 2. CONCLUSIONS Standardized and clinically accessible BOLD-CVR examinations harbor sufficient data to provide specific cerebrovascular reactivity cutoff points for HF staging across individual vascular territories in symptomatic patients with unilateral cerebrovascular steno-occlusive disease.
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Affiliation(s)
- Martina Sebök
- Department of NeurosurgeryUniversity Hospital Zurich, University of ZurichSwitzerland
- Clinical Neuroscience CenterUniversity Hospital Zurich, University of ZurichSwitzerland
| | | | - Cäcilia Mader
- Department of Nuclear MedicineUniversity Hospital Zurich, University of ZurichSwitzerland
| | - Athina Pangalu
- Clinical Neuroscience CenterUniversity Hospital Zurich, University of ZurichSwitzerland
- Department of NeuroradiologyUniversity Hospital Zurich, University of ZurichSwitzerland
| | - Valerie Treyer
- Department of Nuclear MedicineUniversity Hospital Zurich, University of ZurichSwitzerland
| | - Joseph Arnold Fisher
- Department of Anesthesia and Pain ManagementUniversity Health NetworkTorontoOntarioCanada
- Institute of Medical ScienceUniversity of TorontoTorontoOntarioCanada
| | - David John Mikulis
- Institute of Medical ScienceUniversity of TorontoTorontoOntarioCanada
- Joint Department of Medical Imaging and the Functional Neuroimaging LaboratoryUniversity Health NetworkTorontoOntarioCanada
| | - Martin Hüllner
- Department of Nuclear MedicineUniversity Hospital Zurich, University of ZurichSwitzerland
| | - Luca Regli
- Department of NeurosurgeryUniversity Hospital Zurich, University of ZurichSwitzerland
- Clinical Neuroscience CenterUniversity Hospital Zurich, University of ZurichSwitzerland
| | - Jorn Fierstra
- Department of NeurosurgeryUniversity Hospital Zurich, University of ZurichSwitzerland
- Clinical Neuroscience CenterUniversity Hospital Zurich, University of ZurichSwitzerland
| | - Christiaan Hendrik Bas van Niftrik
- Department of NeurosurgeryUniversity Hospital Zurich, University of ZurichSwitzerland
- Clinical Neuroscience CenterUniversity Hospital Zurich, University of ZurichSwitzerland
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Tagliabue S, Kacprzak M, Serra I, Maruccia F, Fischer JB, Riveiro-Vilaboa M, Rey-Perez A, Expósito L, Lindner C, Báguena M, Durduran T, Poca MA. Transcranial, Non-Invasive Evaluation of Potential Misery Perfusion During Hyperventilation Therapy of Traumatic Brain Injury Patients. J Neurotrauma 2023; 40:2073-2086. [PMID: 37125452 PMCID: PMC10541939 DOI: 10.1089/neu.2022.0419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023] Open
Abstract
Hyperventilation (HV) therapy uses vasoconstriction to reduce intracranial pressure (ICP) by reducing cerebral blood volume. However, as HV also lowers cerebral blood flow (CBF), it may provoke misery perfusion (MP), in which the decrease in CBF is coupled with increased oxygen extraction fraction (OEF). MP may rapidly lead to the exhaustion of brain energy metabolites, making the brain vulnerable to ischemia. MP is difficult to detect at the bedside, which is where transcranial hybrid, near-infrared spectroscopies are promising because they non-invasively measure OEF and CBF. We have tested this technology during HV (∼30 min) with bilateral, frontal lobe monitoring to assess MP in 27 sessions in 18 patients with traumatic brain injury. In this study, HV did not lead to MP at a group level (p > 0.05). However, a statistical approach yielded 89 events with a high probability of MP in 19 sessions. We have characterized each statistically significant event in detail and its possible relationship to clinical and radiological status (decompressive craniectomy and presence of a cerebral lesion), without detecting any statistically significant difference (p > 0.05). However, MP detection stresses the need for personalized, real-time assessment in future clinical trials with HV, in order to provide an optimal evaluation of the risk-benefit balance of HV. Our study provides pilot data demonstrating that bedside transcranial hybrid near-infrared spectroscopies could be utilized to assess potential MP.
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Affiliation(s)
- Susanna Tagliabue
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain
| | - Michał Kacprzak
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain
- Nalecz Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences, Warsaw, Poland
| | - Isabel Serra
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain
- Centre de Recerca Matemàtica (CRM), Bellaterra, Spain
| | - Federica Maruccia
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain
- Neurotraumatology and Neurosurgery Research Unit (UNINN), Vall d'Hebron Research Institute (VHIR), Barcelona, Spain
| | - Jonas B Fischer
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain
- HemoPhotonics S.L., Castelldefels (Barcelona), Spain
| | | | - Anna Rey-Perez
- Neurotrauma Intensive Care Unit, and Vall d'Hebron University Hospital, Barcelona, Spain
| | - Lourdes Expósito
- Neurotrauma Intensive Care Unit, and Vall d'Hebron University Hospital, Barcelona, Spain
| | - Claus Lindner
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain
| | - Marcelino Báguena
- Neurotrauma Intensive Care Unit, and Vall d'Hebron University Hospital, Barcelona, Spain
| | - Turgut Durduran
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - María Antonia Poca
- Centre de Recerca Matemàtica (CRM), Bellaterra, Spain
- Department of Neurosurgery, Vall d'Hebron University Hospital, Barcelona, Spain
- Department of Surgery, Universidad Autònoma de Barcelona, Barcelona, Spain
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Takeuchi K, Isozaki M, Higashino Y, Kosaka N, Kikuta KI, Ishida S, Kanamoto M, Takei N, Okazawa H, Kimura H. The Utility of Arterial Transit Time Measurement for Evaluating the Hemodynamic Perfusion State of Patients with Chronic Cerebrovascular Stenosis or Occlusive Disease: Correlative Study between MR Imaging and 15O-labeled H 2O Positron Emission Tomography. Magn Reson Med Sci 2023; 22:289-300. [PMID: 35545508 PMCID: PMC10449557 DOI: 10.2463/mrms.mp.2020-0123] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 02/07/2022] [Indexed: 11/09/2022] Open
Abstract
PURPOSE To verify whether arterial transit time (ATT) mapping can correct arterial spin labeling-cerebral blood flow (ASL-CBF) values and to verify whether ATT is a parameter that correlates with positron emission tomography (PET)-oxygen extraction fraction (OEF) and PET-mean transit time (MTT). METHODS Eleven patients with unilateral major cerebral artery stenosis or occlusion underwent MRI and PET in the chronic or asymptomatic phase. ASL-MRI acquisitions were conducted with each of two post-label delay (PLD) settings (0.7s and 2.0s) using a pseudo-continuous ASL pulse sequence and 3D-spin echo spiral readout with vascular crusher gradient. ATT maps were obtained using a low-resolution pre-scan approach with five PLD settings. Using the ASL perfusion images and ATT mapping, ATT-corrected ASL-CBF images were obtained. Four kinds of ASL-CBF methods (PLD 0.7s with or without ATT correction and PLD 2.0s with or without ATT correction) were compared to PET-CBF, using vascular territory ROIs. ATT and OEF were compared for all ROIs, unaffected side ROIs, and affected side ROIs, respectively. ATT and MTT were compared by the ratio of the affected side to the unaffected side. Transit time-based ROIs were used for the comparison with ATT. RESULTS Comparing ASL-CBF and PET-CBF, the correlation was higher with ATT correction than without correction, and for a PLD of 2.0s compared with 0.7s. The best correlation was for PLD of 2.0s with ATT correction (R2 = 0.547). ROIs on the affected side showed a low but significant correlation between ATT and PET-OEF (R2 = 0.141). There was a low correlation between the ATT ratio and the MTT ratio (R2 = 0.133). CONCLUSION Low-resolution ATT correction may increase the accuracy of ASL-CBF measurements in patients with unilateral major cerebral artery stenosis or occlusion. In addition, ATT itself might have a potential role in detecting compromised hemodynamic state.
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Affiliation(s)
- Kayo Takeuchi
- Department of Radiology, Faculty of Medical Sciences, University of Fukui, Yoshida-gun, Fukui, Japan
| | - Makoto Isozaki
- Department of Neurosurgery, Faculty of Medical Sciences, University of Fukui, Yoshida-gun, Fukui, Japan
| | - Yoshifumi Higashino
- Department of Neurosurgery, Faculty of Medical Sciences, University of Fukui, Yoshida-gun, Fukui, Japan
| | - Nobuyuki Kosaka
- Department of Radiology, Faculty of Medical Sciences, University of Fukui, Yoshida-gun, Fukui, Japan
| | - Ken-ichiro Kikuta
- Department of Neurosurgery, Faculty of Medical Sciences, University of Fukui, Yoshida-gun, Fukui, Japan
| | - Shota Ishida
- Radiological Center, University of Fukui Hospital, Yoshida-gun, Fukui, Japan
| | - Masayuki Kanamoto
- Radiological Center, University of Fukui Hospital, Yoshida-gun, Fukui, Japan
| | - Naoyuki Takei
- Global MR Applications and Workflow, GE Healthcare, Tokyo, Japan
| | - Hidehiko Okazawa
- Biomedical Imaging Research Center, University of Fukui, Yoshida-gun, Fukui, Japan
| | - Hirohiko Kimura
- Department of Radiology, Faculty of Medical Sciences, University of Fukui, Yoshida-gun, Fukui, Japan
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Zedde M, Napoli M, Grisendi I, Assenza F, Moratti C, Valzania F, Pascarella R. Perfusion Status in Lacunar Stroke: A Pathophysiological Issue. Diagnostics (Basel) 2023; 13:2003. [PMID: 37370898 DOI: 10.3390/diagnostics13122003] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 06/02/2023] [Accepted: 06/05/2023] [Indexed: 06/29/2023] Open
Abstract
The pathophysiology of lacunar infarction is an evolving and debated field, where relevant information comes from histopathology, old anatomical studies and animal models. Only in the last years, have neuroimaging techniques allowed a sufficient resolution to directly or indirectly assess the dynamic evolution of small vessel occlusion and to formulate hypotheses about the tissue status and the mechanisms of damage. The core-penumbra concept was extensively explored in large vessel occlusions (LVOs) both from the experimental and clinical point of view. Then, the perfusion thresholds on one side and the neuroimaging techniques studying the perfusion of brain tissue were focused and optimized for LVOs. The presence of a perfusion deficit in the territory of a single small perforating artery was negated for years until the recent proposal of the existence of a perfusion defect in a subgroup of lacunar infarcts by using magnetic resonance imaging (MRI). This last finding opens pathophysiological hypotheses and triggers a neurovascular multidisciplinary reasoning about how to image this perfusion deficit in the acute phase in particular. The aim of this review is to summarize the pathophysiological issues and the application of the core-penumbra hypothesis to lacunar stroke.
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Affiliation(s)
- Marialuisa Zedde
- Neurology Unit, Stroke Unit, AUSL-IRCCS di Reggio Emilia, Via Amendola 2, 42122 Reggio Emilia, Italy
| | - Manuela Napoli
- Neuroradiology Unit, AUSL-IRCCS di Reggio Emilia, Via Amendola 2, 42122 Reggio Emilia, Italy
| | - Ilaria Grisendi
- Neurology Unit, Stroke Unit, AUSL-IRCCS di Reggio Emilia, Via Amendola 2, 42122 Reggio Emilia, Italy
| | - Federica Assenza
- Neurology Unit, Stroke Unit, AUSL-IRCCS di Reggio Emilia, Via Amendola 2, 42122 Reggio Emilia, Italy
| | - Claudio Moratti
- Neuroradiology Unit, AUSL-IRCCS di Reggio Emilia, Via Amendola 2, 42122 Reggio Emilia, Italy
| | - Franco Valzania
- Neurology Unit, Stroke Unit, AUSL-IRCCS di Reggio Emilia, Via Amendola 2, 42122 Reggio Emilia, Italy
| | - Rosario Pascarella
- Neuroradiology Unit, AUSL-IRCCS di Reggio Emilia, Via Amendola 2, 42122 Reggio Emilia, Italy
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Hua J, Dong J, Chen GC, Shen Y. Trends in cognitive function before and after stroke in China. BMC Med 2023; 21:204. [PMID: 37280632 DOI: 10.1186/s12916-023-02908-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 05/24/2023] [Indexed: 06/08/2023] Open
Abstract
BACKGROUND While cognitive impairment after stroke is common, cognitive trends before stroke are poorly understood, especially among the Chinese population who have a relatively high stroke burden. We aimed to model the trajectories of cognitive function before and after new-onset stroke among Chinese. METHODS A total of 13,311 Chinese participants aged ≥ 45 years and without a history of stroke were assessed at baseline between June 2011 and March 2012 and in at least one cognitive test between 2013 (wave 2) and 2018 (wave 4). Cognitive function was assessed using a global cognition score, which included episodic memory, visuospatial abilities, and a 10-item Telephone Interview of Cognitive Status (TICS-10) test to reflect calculation, attention, and orientation abilities. RESULTS During the 7-year follow-up, 610 (4.6%) participants experienced a first stroke. Both stroke and non-stroke groups showed declined cognitive function during follow-up. After adjustment for covariates, there was no significant difference in pre-stroke cognitive trajectories between stroke patients and stroke-free participants. The stroke group showed an acute decline in episodic memory (- 0.123 SD), visuospatial abilities (- 0.169 SD), and global cognition (- 0.135 SD) after stroke onset. In the years following stroke, the decline rate of the TICS-10 test was higher than the rate before stroke (- 0.045 SD/year). CONCLUSIONS Chinese stroke patients had not experienced steeper declines in cognition before stroke compared with stroke-free individuals. Incident stroke was associated with acute declines in global cognition, episodic memory, visuospatial abilities, and accelerated declines in calculation, attention, and orientation abilities.
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Affiliation(s)
- Jianian Hua
- Department of Epidemiology and Biostatistics, School of Public Health, Medical College of Soochow University, 199 Ren'ai Road, Suzhou, 215123, China
- Department of Neurology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Jianye Dong
- Department of Epidemiology and Biostatistics, School of Public Health, Medical College of Soochow University, 199 Ren'ai Road, Suzhou, 215123, China
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Guo-Chong Chen
- Department of Nutrition and Food Hygiene, Suzhou Medical College of Soochow University, 199 Ren'ai Road, Suzhou, 215123, China.
| | - Yueping Shen
- Department of Epidemiology and Biostatistics, School of Public Health, Medical College of Soochow University, 199 Ren'ai Road, Suzhou, 215123, China.
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10
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Heo HY, Tee YK, Harston G, Leigh R, Chappell M. Amide proton transfer imaging in stroke. NMR IN BIOMEDICINE 2023; 36:e4734. [PMID: 35322482 PMCID: PMC9761584 DOI: 10.1002/nbm.4734] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 03/04/2022] [Accepted: 03/21/2022] [Indexed: 05/23/2023]
Abstract
Amide proton transfer (APT) imaging, a variant of chemical exchange saturation transfer MRI, has shown promise in detecting ischemic tissue acidosis following impaired aerobic metabolism in animal models and in human stroke patients due to the sensitivity of the amide proton exchange rate to changes in pH within the physiological range. Recent studies have demonstrated the possibility of using APT-MRI to detect acidosis of the ischemic penumbra, enabling the assessment of stroke severity and risk of progression, monitoring of treatment progress, and prognostication of clinical outcome. This paper reviews current APT imaging methods actively used in ischemic stroke research and explores the clinical aspects of ischemic stroke and future applications for these methods.
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Affiliation(s)
- Hye-Young Heo
- Division of MR Research, Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
| | - Yee Kai Tee
- Lee Kong Chian Faculty of Engineering and Science, University Tunku Abdul Rahman, Malaysia
| | - George Harston
- Acute Stroke Programme, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Richard Leigh
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Michael Chappell
- Radiological Sciences, Mental Health and Clinical Neurosciences, School of Medicine, University of Nottingham, Nottingham, UK
- Nottingham Biomedical Research Centre, Queen’s Medical Centre, University of Nottingham, Nottingham, United Kingdom, UK
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Ogasawara K, Takahashi T, Igarashi S, Yabuki M, Omori D, Akamatsu Y, Chida K, Kobayashi M, Fujiwara S, Terasaki K. Effect of the addition of 123I-iomazenil single-photon emission computed tomography to brain perfusion single-photon emission computed tomography on the detection accuracy of misery perfusion in adult patients with ischemic moyamoya disease. Ann Nucl Med 2023; 37:280-288. [PMID: 36805493 DOI: 10.1007/s12149-023-01825-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 02/06/2023] [Indexed: 02/21/2023]
Abstract
OBJECTIVE The present prospective study aimed to determine whether the addition of 123I-iomazenil (IMZ) single-photon emission computed tomography (SPECT) to brain perfusion SPECT could improve the detection accuracy of misery perfusion on positron emission tomography (PET) in adult patients with ischemic moyamoya disease (MMD). METHODS Oxygen extraction fraction (OEF) and brain perfusion were assessed using 15O gas PET and N-isopropyl-p-[123I]-iodoamphetamine (IMP) SPECT, respectively, in 137 patients. IMZ SPECT was also performed. Regions of interest (ROIs) were automatically placed in the five middle cerebral artery (MCA) territories ipsilateral to the symptomatic cerebral hemisphere and in the contralateral posterior cerebral artery territory using a three-dimensional stereotaxic ROI template. The radioactive count of the MCA ROI to the contralateral posterior cerebral artery ROI was calculated on IMP SPECT (relative SPECT-IMP uptake) and IMZ SPECT (relative SPECT-IMZ uptake). The relative SPECT-IMZ uptake to the relative SPECT-IMP uptake was also calculated (relative SPECT-IMZ/IMP uptake). Of the five MCA ROIs in the symptomatic cerebral hemisphere in each patient, the ROI with the highest PET-OEF value (one ROI per patient) was selected for analysis. RESULTS Significant correlations were observed between the PET-OEF and relative SPECT-IMP uptake (correlation coefficient, - 0.683) and relative SPECT-IMZ/IMP uptake (correlation coefficient, 0.875). The area under the receiver operating characteristic curve for detecting misery perfusion (PET-OEF > 51.3%) was significantly greater for the relative SPECT-IMZ/IMP uptake than for the relative SPECT-IMP uptake (difference between areas, 0.080; p = 0.0004). The sensitivity, specificity, and positive- and negative-predictive values for the relative SPECT-IMZ/IMP uptake for detecting misery perfusion were 100%, 92%, 81%, and 100%, respectively. The specificity and positive-predictive value were significantly greater for the relative SPECT-IMZ/IMP uptake than for the relative SPECT-IMP uptake. CONCLUSIONS The addition of IMZ SPECT to brain perfusion SPECT improves the detection accuracy of misery perfusion on PET in adult patients with ischemic MMD.
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Affiliation(s)
- Kuniaki Ogasawara
- Department of Neurosurgery, Iwate Medical University, Iwate, Japan. .,Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan.
| | - Tatsuhiko Takahashi
- Department of Neurosurgery, Iwate Medical University, Iwate, Japan.,Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan
| | - Suguru Igarashi
- Department of Neurosurgery, Iwate Medical University, Iwate, Japan.,Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan
| | - Masahiro Yabuki
- Department of Neurosurgery, Iwate Medical University, Iwate, Japan.,Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan
| | - Daisuke Omori
- Department of Neurosurgery, Iwate Medical University, Iwate, Japan.,Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan
| | - Yosuke Akamatsu
- Department of Neurosurgery, Iwate Medical University, Iwate, Japan
| | - Kohei Chida
- Department of Neurosurgery, Iwate Medical University, Iwate, Japan.,Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan
| | - Masakazu Kobayashi
- Department of Neurosurgery, Iwate Medical University, Iwate, Japan.,Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan
| | - Shunrou Fujiwara
- Department of Neurosurgery, Iwate Medical University, Iwate, Japan
| | - Kazunori Terasaki
- Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan
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12
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Takahashi T, Uwano I, Akamatsu Y, Chida K, Kobayashi M, Yoshida K, Fujiwara S, Kubo Y, Sasaki M, Ogasawara K. Prediction of cerebral hyperperfusion following carotid endarterectomy using intravoxel incoherent motion magnetic resonance imaging. J Stroke Cerebrovasc Dis 2023; 32:106909. [PMID: 36442280 DOI: 10.1016/j.jstrokecerebrovasdis.2022.106909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 11/17/2022] [Accepted: 11/21/2022] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVES One of the risk factors for cerebral hyperperfusion following carotid endarterectomy (CEA) is a chronic reduction in cerebral perfusion pressure due to internal carotid artery (ICA) stenosis, which is clinically detected as increased cerebral blood volume (CBV). The perfusion fraction (f) is one of the intra-voxel incoherent motion (IVIM) parameters obtained using magnetic resonance (MR) imaging that theoretically reflects CBV. The present study aimed to determine whether preoperative IVIM-f on MR imaging predicts development of cerebral hyperperfusion following CEA. MATERIALS AND METHODS Sixty-eight patients with unilateral ICA stenosis (≥ 70%) underwent preoperative diffusion-weighted 3-T MR imaging, and IVIM-f maps were generated from these data. Quantitative brain perfusion single-photon emission computed tomography (SPECT) was performed before and immediately after CEA. Regions-of-interest (ROIs) were automatically placed in the bilateral middle cerebral artery territories in all images using a three-dimensional stereotactic ROI template, and affected-to-contralateral ratios in the ROIs were calculated on IVIM-f maps. RESULTS Nine patients (13%) exhibited postoperative hyperperfusion (cerebral blood flow increases of ≥ 100% compared with preoperative values in the ROIs on brain perfusion SPECT). Only high IVIM-f ratios were significantly associated with the occurrence of postoperative hyperperfusion (95% confidence interval, 253.8-6774.2; p = 0.0031) on logistic regression analysis. The sensitivity, specificity, and positive and negative predictive values of the IVIM-f ratio to predict the occurrence of postoperative hyperperfusion were 100%, 81%, 45%, and 100%, respectively. CONCLUSIONS Preoperative IVIM-f on MR imaging can predict development of cerebral hyperperfusion following CEA.
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Affiliation(s)
- Tatsuhiko Takahashi
- Department of Neurosurgery, Iwate Medical University, Iwate, Japan; Division of Ultrahigh Field MRI, Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan.
| | - Ikuko Uwano
- Division of Ultrahigh Field MRI, Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan.
| | - Yosuke Akamatsu
- Department of Neurosurgery, Iwate Medical University, Iwate, Japan; Division of Ultrahigh Field MRI, Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan.
| | - Kohei Chida
- Department of Neurosurgery, Iwate Medical University, Iwate, Japan; Division of Ultrahigh Field MRI, Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan.
| | - Masakazu Kobayashi
- Department of Neurosurgery, Iwate Medical University, Iwate, Japan; Division of Ultrahigh Field MRI, Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan.
| | - Kenji Yoshida
- Department of Neurosurgery, Iwate Medical University, Iwate, Japan; Division of Ultrahigh Field MRI, Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan.
| | - Shunrou Fujiwara
- Department of Neurosurgery, Iwate Medical University, Iwate, Japan; Division of Ultrahigh Field MRI, Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan.
| | - Yoshitaka Kubo
- Department of Neurosurgery, Iwate Medical University, Iwate, Japan; Division of Ultrahigh Field MRI, Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan.
| | - Makoto Sasaki
- Division of Ultrahigh Field MRI, Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan.
| | - Kuniaki Ogasawara
- Department of Neurosurgery, Iwate Medical University, Iwate, Japan; Division of Ultrahigh Field MRI, Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan.
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13
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Gleißner C, Kaczmarz S, Kufer J, Schmitzer L, Kallmayer M, Zimmer C, Wiestler B, Preibisch C, Göttler J. Hemodynamic MRI parameters to predict asymptomatic unilateral carotid artery stenosis with random forest machine learning. FRONTIERS IN NEUROIMAGING 2023; 1:1056503. [PMID: 37555162 PMCID: PMC10406220 DOI: 10.3389/fnimg.2022.1056503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 12/20/2022] [Indexed: 08/10/2023]
Abstract
BACKGROUND Internal carotid artery stenosis (ICAS) can cause stroke and cognitive decline. Associated hemodynamic impairments, which are most pronounced within individual watershed areas (iWSA) between vascular territories, can be assessed with hemodynamic-oxygenation-sensitive MRI and may help to detect severely affected patients. We aimed to identify the most sensitive parameters and volumes of interest (VOI) to predict high-grade ICAS with random forest machine learning. We hypothesized an increased predictive ability considering iWSAs and a decreased cognitive performance in correctly classified patients. MATERIALS AND METHODS Twenty-four patients with asymptomatic, unilateral, high-grade carotid artery stenosis and 24 age-matched healthy controls underwent MRI comprising pseudo-continuous arterial spin labeling (pCASL), breath-holding functional MRI (BH-fMRI), dynamic susceptibility contrast (DSC), T2 and T2* mapping, MPRAGE and FLAIR. Quantitative maps of eight perfusion, oxygenation and microvascular parameters were obtained. Mean values of respective parameters within and outside of iWSAs split into gray (GM) and white matter (WM) were calculated for both hemispheres and for interhemispheric differences resulting in 96 features. Random forest classifiers were trained on whole GM/WM VOIs, VOIs considering iWSAs and with additional feature selection, respectively. RESULTS The most sensitive features in decreasing order were time-to-peak (TTP), cerebral blood flow (CBF) and cerebral vascular reactivity (CVR), all of these inside of iWSAs. Applying iWSAs combined with feature selection yielded significantly higher receiver operating characteristics areas under the curve (AUC) than whole GM/WM VOIs (AUC: 0.84 vs. 0.90, p = 0.039). Correctly predicted patients presented with worse cognitive performances than frequently misclassified patients (Trail-making-test B: 152.5s vs. 94.4s, p = 0.034). CONCLUSION Random forest classifiers trained on multiparametric MRI data allow identification of the most relevant parameters and VOIs to predict ICAS, which may improve personalized treatments.
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Affiliation(s)
- Carina Gleißner
- Department of Diagnostic and Interventional Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Stephan Kaczmarz
- Department of Diagnostic and Interventional Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany
- Philips GmbH Market DACH, Hamburg, Germany
- TUM Neuroimaging Center, School of Medicine, Technical University of Munich, Munich, Germany
| | - Jan Kufer
- Department of Diagnostic and Interventional Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany
- TUM Neuroimaging Center, School of Medicine, Technical University of Munich, Munich, Germany
| | - Lena Schmitzer
- Department of Diagnostic and Interventional Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany
- TUM Neuroimaging Center, School of Medicine, Technical University of Munich, Munich, Germany
| | - Michael Kallmayer
- Department of Vascular and Endovascular Surgery, School of Medicine, Technical University of Munich, Munich, Germany
| | - Claus Zimmer
- Department of Diagnostic and Interventional Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Benedikt Wiestler
- Department of Diagnostic and Interventional Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Christine Preibisch
- Department of Diagnostic and Interventional Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany
- TUM Neuroimaging Center, School of Medicine, Technical University of Munich, Munich, Germany
- Clinic for Neurology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Jens Göttler
- Department of Diagnostic and Interventional Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany
- TUM Neuroimaging Center, School of Medicine, Technical University of Munich, Munich, Germany
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14
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Zhang Y, Song S, Li Z, Huang B, Geng Y, Zhang L. The Application of Software "Rapid Processing of Perfusion and Diffusion" in Acute Ischemic Stroke. Brain Sci 2022; 12:1451. [PMID: 36358379 PMCID: PMC9688896 DOI: 10.3390/brainsci12111451] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 10/20/2022] [Accepted: 10/20/2022] [Indexed: 08/30/2023] Open
Abstract
In the event of an acute ischemic stroke, saving the penumbra is the most important aspect of early treatment. The rapid and accurate identification of ischemic penumbra plays a key role in its comprehensive treatment. At present, the identification method and evaluation standard of ischemic penumbra have not been unified. Numerous pieces of software identifying ischemic penumbra have been developed, such as rapid processing of perfusion and diffusion (RAPID), Sphere, Vitrea, and computed tomography perfusion+ (CTP+). The RAPID software, analyzing and integrating multi-mode image data (mainly based on perfusion weighted imaging (PWI) or computed tomography perfusion (CTP) images, shows good performance in identifying ischemic penumbra and has been utilized for the assessment of ischemic penumbra in many ischemic stroke clinical studies, achieving good outcomes and promoting the transition from "time window" to "tissue window" in the treatment of early stage AIS. To obtain a comprehensive understanding of the RAPID software and its accuracy in evaluating ischemic penumbra, this paper reviews the background and development of the RAPID software, summarizes the published acute cerebral infarction trials using the RAPID software, generalizes the threshold parameters in different time windows, and further discusses its application and limitations.
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Affiliation(s)
- Yudi Zhang
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Shuang Song
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Zhenzhong Li
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Boyuan Huang
- Department of Radiology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Yanlu Geng
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
- Department of Neurology, Central Hospital of Qinghe County, Xingtai 054800, China
| | - Lihong Zhang
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
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15
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Choi EJ, Westmacott R, Kirkham FJ, Robertson A, Muthusami P, Shroff M, Moharir M, Williams T, Dirks P, MacGregor D, Slim M, Pulcine E, Bhathal I, Kaseka ML, Kassner A, Logan W, deVeber G, Dlamini N. Fronto-Parietal and White Matter Haemodynamics Predict Cognitive Outcome in Children with Moyamoya Independent of Stroke. Transl Stroke Res 2022; 13:757-773. [PMID: 35338434 DOI: 10.1007/s12975-022-01003-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 03/03/2022] [Accepted: 03/04/2022] [Indexed: 10/18/2022]
Abstract
Moyamoya disease is a major arteriopathy characterised by progressive steno-occlusion of the arteries of the circle of Willis. Studies in adults with moyamoya suggest an association between abnormal fronto-parietal and white matter regional haemodynamics and cognitive impairments, even in the absence of focal infarction. However, these associations have not been investigated in children with moyamoya. We examined the relationship between regional haemodynamics and ratings of intellectual ability and executive function, using hypercapnic challenge blood oxygen level-dependent magnetic resonance imaging of cerebrovascular reactivity in a consecutive cohort of children with confirmed moyamoya. Thirty children were included in the final analysis (mean age: 12.55 ± 3.03 years, 17 females, 15 idiopathic moyamoya and 15 syndromic moyamoya). Frontal haemodynamics were abnormal in all regardless of stroke history and comorbidity, but occipital lobe haemodynamics were also abnormal in children with syndromic moyamoya. Executive function deficits were noted in both idiopathic and syndromic moyamoya, whereas intellectual ability was impaired in syndromic moyamoya, even in the absence of stroke. Analysis of the relative effect of regional abnormal haemodynamics on cognitive outcomes demonstrated that executive dysfunction was predominantly explained by right parietal and white matter haemodynamics independent of stroke and comorbidity, while posterior circulation haemodynamics predicted intellectual ability. These results suggest that parietal and posterior haemodynamics play a compensatory role in overcoming frontal vulnerability and cognitive impairment.
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Affiliation(s)
- Eun Jung Choi
- Neurosciences and Mental Health Program, Stroke Imaging Laboratory for Children, The Hospital for Sick Children, Toronto, ON, Canada
| | - Robyn Westmacott
- Department of Neuropsychology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Fenella J Kirkham
- Developmental Neurosciences and Biomedical Research Centre, University College London Great Ormond Street Institute of Child Health, London, UK
| | - Amanda Robertson
- Neurosciences and Mental Health Program, Stroke Imaging Laboratory for Children, The Hospital for Sick Children, Toronto, ON, Canada
- Stroke Program, Division of Neurology, Department of Paediatrics, The Hospital for Sick Children, Toronto, ON, Canada
- Child Health Evaluative Sciences Program, The Hospital for Sick Children, Toronto, ON, Canada
| | - Prakash Muthusami
- Diagnostic Imaging, The Hospital for Sick Children, ON, Toronto, Canada
- Medical Imaging, University of Toronto, ON, Toronto, Canada
| | - Manohar Shroff
- Diagnostic Imaging, The Hospital for Sick Children, ON, Toronto, Canada
- Medical Imaging, University of Toronto, ON, Toronto, Canada
| | - Mahendranath Moharir
- Stroke Program, Division of Neurology, Department of Paediatrics, The Hospital for Sick Children, Toronto, ON, Canada
| | - Tricia Williams
- Department of Neuropsychology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Peter Dirks
- Department of Neurosurgery, The Hospital for Sick Children, Toronto, ON, Canada
| | - Daune MacGregor
- Stroke Program, Division of Neurology, Department of Paediatrics, The Hospital for Sick Children, Toronto, ON, Canada
| | - Mahmoud Slim
- Child Health Evaluative Sciences Program, The Hospital for Sick Children, Toronto, ON, Canada
| | - Elizabeth Pulcine
- Stroke Program, Division of Neurology, Department of Paediatrics, The Hospital for Sick Children, Toronto, ON, Canada
| | - Ishvinder Bhathal
- Stroke Program, Division of Neurology, Department of Paediatrics, The Hospital for Sick Children, Toronto, ON, Canada
| | - Matsanga Leyila Kaseka
- Stroke Program, Division of Neurology, Department of Paediatrics, The Hospital for Sick Children, Toronto, ON, Canada
| | - Andrea Kassner
- Medical Imaging, University of Toronto, ON, Toronto, Canada
- Department of Translational Medicine, The Hospital for Sick Children, Peter Gilgan Centre for Research & Learning, ON, Toronto, Canada
| | - William Logan
- Stroke Program, Division of Neurology, Department of Paediatrics, The Hospital for Sick Children, Toronto, ON, Canada
| | - Gabrielle deVeber
- Stroke Program, Division of Neurology, Department of Paediatrics, The Hospital for Sick Children, Toronto, ON, Canada
- Child Health Evaluative Sciences Program, The Hospital for Sick Children, Toronto, ON, Canada
| | - Nomazulu Dlamini
- Neurosciences and Mental Health Program, Stroke Imaging Laboratory for Children, The Hospital for Sick Children, Toronto, ON, Canada.
- Stroke Program, Division of Neurology, Department of Paediatrics, The Hospital for Sick Children, Toronto, ON, Canada.
- Child Health Evaluative Sciences Program, The Hospital for Sick Children, Toronto, ON, Canada.
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16
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Mohr JP. Carotid Sources of Stroke. Stroke 2022; 53:e259-e263. [PMID: 35759546 DOI: 10.1161/strokeaha.122.038567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The ancient Greeks used the term karotides for the great arteries in the neck, compression of which could plunge the victim into karoun: deep sleep or stupor. The artery name aside, studies of the patterns of brain infarction and their clinical severity have been an unbroken chain of growing sophistication in the past 150 years. Two main patterns emerged: perfusion failure with high-convexity infarction from hemodynamically important ipsilateral carotid stenosis or embolism from nonstenosing carotid plaque.
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Affiliation(s)
- J P Mohr
- Daniel Sciarra Professor of Neurology, Doris & Stanley Tananbaum Stroke Center, Neurological Institute, Columbia University Irving Medical Center, NY
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17
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What Are We Measuring? A Refined Look at the Process of Disrupted Autoregulation and the Limitations of Cerebral Perfusion Pressure in Preventing Secondary Injury after Traumatic Brain Injury. Clin Neurol Neurosurg 2022; 221:107389. [PMID: 35961231 DOI: 10.1016/j.clineuro.2022.107389] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Revised: 07/19/2022] [Accepted: 07/25/2022] [Indexed: 11/23/2022]
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18
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Li J, Chen Y, Peng C, Hong X, Liu H, Fang J, Zhuang R, Pan W, Zhang D, Guo Z, Zhang X. Micro-SPECT Imaging of Acute Ischemic Stroke with Radioiodinated Riboflavin in Rat MCAO Models via Riboflavin Transporter Targeting. ACS Chem Neurosci 2022; 13:1966-1973. [PMID: 35758284 DOI: 10.1021/acschemneuro.2c00177] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Riboflavin transporter-3 (RFVT3) is a recently discovered and novel biomarker for the theranostics of nervous system diseases. RFVT3 is significantly overexpressed in cerebral injury after ischemic stroke. Herein, we first reported an RFVT3-targeted tracer 131I-riboflavin (131I-RFLA) for SPECT imaging of ischemic stroke in vivo. 131I-RFLA was radiosynthesized by the iodogen-coating method. 131I-RFLA possessed a radiochemical yield of 69.2 ± 3.7% and greater than 95% radiochemical purity. The representative SPECT/CT images using 131I-RFLA demonstrated the conspicuously increased tracer uptake in the cerebral injury by comparison with the contralateral normal brain at 1 h and 3 and 7 d after stroke. Ex vivo autoradiography demonstrated that the ratio of infarcted to normal brain uptake was 3.63 and it was decreased to 1.98 after blocking, which reconfirmed the results of SPECT images. Importantly, a significant correlation was identified between RFVT3 expression and brain injury by H&E and immunohistochemistry staining. Therefore, RFVT3 is a new and potential biomarker for the early diagnosis of ischemic stroke. In addition, 131I-RFLA is a promising SPECT tracer for imaging RFVT3-related ischemic cerebral injury in vivo.
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Affiliation(s)
- Jindian Li
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics & Center for Molecular Imaging and Translational Medicine, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Yingxi Chen
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics & Center for Molecular Imaging and Translational Medicine, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Chenyu Peng
- Department of Radiology, The First Affiliated Hospital of Xiamen University, Xiamen 361003, China
| | - Xingfang Hong
- Laboratory of Pathogen Biology, School of Basic Medical, Dali University, Dali 671000, China
| | - Huanhuan Liu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics & Center for Molecular Imaging and Translational Medicine, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Jianyang Fang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics & Center for Molecular Imaging and Translational Medicine, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Rongqiang Zhuang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics & Center for Molecular Imaging and Translational Medicine, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Weimin Pan
- Department of Nuclear Medicine, Xiang'an Hospital Affiliated to Xiamen University, Xiamen 361102, China
| | - Deliang Zhang
- Department of Nuclear Medicine, Xiang'an Hospital Affiliated to Xiamen University, Xiamen 361102, China
| | - Zhide Guo
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics & Center for Molecular Imaging and Translational Medicine, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Xianzhong Zhang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics & Center for Molecular Imaging and Translational Medicine, School of Public Health, Xiamen University, Xiamen 361102, China
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Kimura K, Kubo Y, Dobashi K, Katakura Y, Chida K, Kobayashi M, Yoshida K, Fujiwara S, Terasaki K, Kawamura T, Ogasawara K. Angiographic, Cerebral Hemodynamic, and Cognitive Outcomes of Indirect Revascularization Surgery Alone for Adult Patients With Misery Perfusion due to Ischemic Moyamoya Disease. Neurosurgery 2022; 90:676-683. [PMID: 35311740 DOI: 10.1227/neu.0000000000001907] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 12/05/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Revascularization surgery for adult patients with ischemic moyamoya disease (MMD) may improve both cognitive function and cerebral perfusion. OBJECTIVE To determine angiographic, cerebral hemodynamic, and cognitive outcomes of indirect revascularization surgery alone for adult patients with misery perfusion due to ischemic MMD (IDR group) and to test the superiority of indirect revascularization surgery for cognitive improvement by conducting comparisons with historical control patients who had undergone direct revascularization surgery (DR group) through prospective cohort study with historical controls. METHODS Twenty adult patients with cerebral misery perfusion underwent encephalo-duro-myo-arterio-pericranial-synangiosis alone. Cerebral angiography through arterial catheterization, brain perfusion single-photon emission computed tomography, and neuropsychological testing were performed preoperatively and at 6 months postoperatively. RESULTS In 17 patients of the IDR group, collateral flows that were newly formed after surgery on angiograms fed more than one-third of the middle cerebral artery (MCA) cortical territory. In the IDR group, perfusion in the MCA territory was significantly increased after surgery (P < .0001), and the difference in MCA perfusion between before and after surgery was significantly greater (P = .0493) compared with the DR group. Improved cognition was significantly more frequent in the IDR group (65%) than in the DR group (31%, P = .0233). CONCLUSION Indirect revascularization surgery alone forms sufficient collateral circulation, improves cerebral hemodynamics, and recovers cognitive function in adult patients with misery perfusion due to ischemic MMD. The latter 2 beneficial effects may be higher when compared with patients undergoing direct revascularization surgery.
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Affiliation(s)
- Kazuto Kimura
- Department of Neurosurgery, School of Medicine, Iwate Medical University, Japan
| | - Yoshitaka Kubo
- Department of Neurosurgery, School of Medicine, Iwate Medical University, Japan
| | - Kazumasa Dobashi
- Department of Neurosurgery, School of Medicine, Iwate Medical University, Japan
| | - Yasukazu Katakura
- Department of Neurosurgery, School of Medicine, Iwate Medical University, Japan
| | - Kohei Chida
- Department of Neurosurgery, School of Medicine, Iwate Medical University, Japan
- Institute for Biomedical Sciences, School of Medicine, Iwate Medical University, Japan
| | - Masakazu Kobayashi
- Department of Neurosurgery, School of Medicine, Iwate Medical University, Japan
- Institute for Biomedical Sciences, School of Medicine, Iwate Medical University, Japan
| | - Kenji Yoshida
- Department of Neurosurgery, School of Medicine, Iwate Medical University, Japan
| | - Shunrou Fujiwara
- Department of Neurosurgery, School of Medicine, Iwate Medical University, Japan
| | - Kazunori Terasaki
- Institute for Biomedical Sciences, School of Medicine, Iwate Medical University, Japan
| | | | - Kuniaki Ogasawara
- Department of Neurosurgery, School of Medicine, Iwate Medical University, Japan
- Institute for Biomedical Sciences, School of Medicine, Iwate Medical University, Japan
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Yasuda S, Katakura Y, Kubo Y, Dobashi K, Kimura K, Fujiwara S, Chida K, Akamatsu Y, Kobayashi M, Yoshida K, Terasaki K, Ogasawara K. Recovery of cortical neurotransmitter receptor function and its impact on cognitive improvement after indirect revascularization surgery alone for adult patients with ischemic moyamoya disease: 123I-iomazenil single-photon emission computed tomography study. World Neurosurg 2022; 164:e1135-e1142. [PMID: 35660480 DOI: 10.1016/j.wneu.2022.05.118] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/25/2022] [Accepted: 05/25/2022] [Indexed: 10/18/2022]
Abstract
OBJECTIVE Brain 123I-iomazenil single-photon emission computed tomography (SPECT) can assess the distribution of the binding potential of central benzodiazepine receptors in the cerebral cortex. This binding potential may reflect neuronal function in viable tissues. The present prospective study using brain 123I-iomazenil SPECT aimed to determine whether improvements in cognitive function after indirect revascularization surgery alone are associated with postoperative recovery in neurotransmitter receptor function in the affected cerebral hemisphere among adult patients with moyamoya disease (MMD) accompanied by ischemic presentation due to misery perfusion. METHODS Twenty-two patients who underwent indirect revascularization surgery alone also underwent brain SPECT scanning at 180 minutes after 123I-iomazenil administration and neuropsychological testing before and at 6 months after surgery. The affected-to-contralateral cerebral hemispheric asymmetry of tracer uptake before and after surgery was then calculated. RESULTS The asymmetry of tracer uptake was significantly increased after surgery (p < 0.0001). A significant difference between the pre- and postoperative asymmetry of tracer uptake was seen in patients with improved cognition compared with those with unchanged cognition (p = 0.0001). The area under the receiver operating characteristic curve was 0.99 for the difference between the pre- and postoperative asymmetry of tracer uptake to assess the ability to discriminate patients with improved cognition from those with unchanged cognition. CONCLUSIONS Improvements in cognitive function after indirect revascularization surgery alone are associated with postoperative recovery in the binding potential of central benzodiazepine receptors in the affected cerebral hemisphere in adult patients with MMD accompanied by ischemic presentation due to misery perfusion.
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Affiliation(s)
- Sara Yasuda
- Department of Neurosurgery, Iwate Medical University School of Medicine, Yahaba, Japan
| | - Yasukazu Katakura
- Department of Neurosurgery, Iwate Medical University School of Medicine, Yahaba, Japan
| | - Yoshitaka Kubo
- Department of Neurosurgery, Iwate Medical University School of Medicine, Yahaba, Japan
| | - Kazumasa Dobashi
- Department of Neurosurgery, Iwate Medical University School of Medicine, Yahaba, Japan
| | - Kazuto Kimura
- Department of Neurosurgery, Iwate Medical University School of Medicine, Yahaba, Japan
| | - Shunrou Fujiwara
- Department of Neurosurgery, Iwate Medical University School of Medicine, Yahaba, Japan
| | - Kohei Chida
- Department of Neurosurgery, Iwate Medical University School of Medicine, Yahaba, Japan
| | - Yosuke Akamatsu
- Department of Neurosurgery, Iwate Medical University School of Medicine, Yahaba, Japan
| | - Masakazu Kobayashi
- Department of Neurosurgery, Iwate Medical University School of Medicine, Yahaba, Japan
| | - Kenji Yoshida
- Department of Neurosurgery, Iwate Medical University School of Medicine, Yahaba, Japan
| | - Kazunori Terasaki
- Institute for Biomedical Sciences, Iwate Medical University School of Medicine, Yahaba, Japan
| | - Kuniaki Ogasawara
- Department of Neurosurgery, Iwate Medical University School of Medicine, Yahaba, Japan.
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21
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Kameyama M, Momose T, Ishibashi K, Ishii K. A Novel Proposal for an Index for Regional Cerebral Perfusion Pressure – A Theoretical Approach Using Fluid Dynamics. Front Neurol 2022; 12:765463. [PMID: 35173665 PMCID: PMC8841875 DOI: 10.3389/fneur.2021.765463] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 12/17/2021] [Indexed: 11/16/2022] Open
Abstract
Cerebral blood flow (CBF) / cerebral blood volume (CBV) ratio derived by [15O] H2O/ CO2 and CO positron emission tomography (PET) examination has been used as an index for cerebral perfusion pressure (CPP). CBF/CBV was demonstrated to be related mean arterial pressure (MAP) in baboons. However, this formula has not been confirmed to be proportionate to CPP. We have developed a new index for CPP using the Poiseuille equation based on a simple model. Our model suggests that CBF/CBV2 is proportionate to CPP and that it is mathematically a more accurate index than CBF/CBV. This new index needs experimental validation in the future.
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Affiliation(s)
- Masashi Kameyama
- Department of Diagnostic Radiology, Tokyo Metropolitan Geriatric Hospital and Institute of Gerontology, Tokyo, Japan
- *Correspondence: Masashi Kameyama
| | - Toshimitsu Momose
- Department of Nuclear Medicine, Graduate School of Medicine, The International University of Health and Welfare, Narita, Japan
| | - Kenji Ishibashi
- Research Team for Neuroimaging, Tokyo Metropolitan Geriatric Hospital and Institute of Gerontology, Tokyo, Japan
| | - Kenji Ishii
- Research Team for Neuroimaging, Tokyo Metropolitan Geriatric Hospital and Institute of Gerontology, Tokyo, Japan
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22
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Powers WJ, An H, Diringer MN. Cerebral Blood Flow and Metabolism. Stroke 2022. [DOI: 10.1016/b978-0-323-69424-7.00003-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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23
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Yamauchi H, Kagawa S, Kusano K, Ito M, Okuyama C. Visit-to-Visit Blood PressureVariations and Hemodynamic Deterioration in Atherosclerotic Major Cerebral ArteryDisease. J Stroke Cerebrovasc Dis 2021; 31:106206. [PMID: 34781205 DOI: 10.1016/j.jstrokecerebrovasdis.2021.106206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Revised: 10/18/2021] [Accepted: 10/24/2021] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE Visit-to-visit variations in blood pressure (BP) in patients with atherosclerotic major cerebral artery disease could impair the function of cerebral collaterals, leading to hemodynamic deterioration at follow-up. However, few studies have investigated the relationship between visit-to-visit BP variability and changes in hemodynamic parameters at follow-up. MATERIALS AND METHODS We evaluated 35 medically treated patients with atherosclerotic internal carotid artery or middle cerebral artery disease with no ischemic episodes during follow-up (mean: 35 ± 20 months); these patients had a three-time visit for positron emission tomography examinations with 15O-gas. Differences in the mean hemispheric values of hemodynamic parameters in the cortical territory of the diseased artery between the first and third examinations (changes at follow-up) were correlated with the coefficient of variation (CoV) in three systolic BP (SBP) values at the three examinations (BP variability during follow-up). RESULTS CoV values were negatively correlated with changes in oxygen metabolism or cerebral blood flow/cerebral blood volume (CBF/CBV) ratio. In 17 patients with higher CoV values (> group median, 0.072), decreases in CBF, cerebral metabolic rate of oxygen, and CBF/CBV ratio were observed at follow-up; CBV decreased in 18 patients without elevated CoV. A higher CoV was associated with a lack of statin use. CONCLUSION In patients with atherosclerotic major cerebral artery disease, high visit-to-visit SBP variations during follow-up may be associated with deterioration in cerebral hemodynamics and metabolism.
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Affiliation(s)
- Hiroshi Yamauchi
- Division of PET Imaging, Shiga Medical Center Research Institute, 5-4-30 Moriyama, Moriyama 524-8524, Japan.
| | - Shinya Kagawa
- Division of PET Imaging, Shiga Medical Center Research Institute, 5-4-30 Moriyama, Moriyama 524-8524, Japan
| | - Kuninori Kusano
- Division of PET Imaging, Shiga Medical Center Research Institute, 5-4-30 Moriyama, Moriyama 524-8524, Japan
| | - Miki Ito
- Division of PET Imaging, Shiga Medical Center Research Institute, 5-4-30 Moriyama, Moriyama 524-8524, Japan
| | - Chio Okuyama
- Division of PET Imaging, Shiga Medical Center Research Institute, 5-4-30 Moriyama, Moriyama 524-8524, Japan
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24
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Davis SM, Donnan GA. Ischemic Penumbra: A Personal View. Cerebrovasc Dis 2021; 50:656-665. [PMID: 34736251 DOI: 10.1159/000519730] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 09/16/2021] [Indexed: 11/19/2022] Open
Abstract
The concept of the ischemic penumbra was defined over 40 years ago by Lindsay Symon and his group and is now an established principle of all acute ischemic stroke therapies. These reperfusion treatments rescue threatened, critically hypoperfused brain tissue and have been proven to improve clinical outcomes. We have been fortunate to have observed and played a small part in the penumbral story from its beginnings in the 1970s to its pivotal position today. Over this period, we have witnessed penumbral imaging evolve from positron emission tomography through to magnetic resonance imaging and now predominantly computed tomography perfusion, with the advent of automated imaging facilitating case selection for reperfusion therapies. We and others have conducted clinical trials using penumbral imaging to extend the time window for intravenous thrombolysis and select patients for thrombectomy. Together with the concept of fast- and slow-growing ischemic infarct patterns, this embeds the penumbral principle in everyday clinical management. The opportunity now exists to make penumbral imaging even more portable, affordable, and more widely available using mobile platforms, novel imaging techniques, digital linkage, and artificial intelligence.
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Affiliation(s)
- Stephen M Davis
- Departments of Medicine and Neurology, Melbourne Brain Centre at the Royal Melbourne Hospital, University of Melbourne, Victoria, Victoria, Australia
| | - Geoffrey A Donnan
- Departments of Medicine and Neurology, Melbourne Brain Centre at the Royal Melbourne Hospital, University of Melbourne, Victoria, Victoria, Australia
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25
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Lu J, Mei Q, Hou X, Manaenko A, Zhou L, Liebeskind DS, Zhang JH, Li Y, Hu Q. Imaging Acute Stroke: From One-Size-Fit-All to Biomarkers. Front Neurol 2021; 12:697779. [PMID: 34630278 PMCID: PMC8497192 DOI: 10.3389/fneur.2021.697779] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 06/30/2021] [Indexed: 12/27/2022] Open
Abstract
In acute stroke management, time window has been rigidly used as a guide for decades and the reperfusion treatment is only available in the first few limited hours. Recently, imaging-based selection of patients has successfully expanded the treatment window out to 16 and even 24 h in the DEFUSE 3 and DAWN trials, respectively. Recent guidelines recommend the use of imaging techniques to guide therapeutic decision-making and expanded eligibility in acute ischemic stroke. A tissue window is proposed to replace the time window and serve as the surrogate marker for potentially salvageable tissue. This article reviews the evolution of time window, addresses the advantage of a tissue window in precision medicine for ischemic stroke, and discusses both the established and emerging techniques of neuroimaging and their roles in defining a tissue window. We also emphasize the metabolic imaging and molecular imaging of brain pathophysiology, and highlight its potential in patient selection and treatment response prediction in ischemic stroke.
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Affiliation(s)
- Jianfei Lu
- Central Laboratory, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Qiyong Mei
- Department of Neurosurgery, Changzheng Hospital, Navy Medical University, Shanghai, China
| | - Xianhua Hou
- Department of Neurology, Southwest Hospital, Army Medical University, Chongqing, China
| | - Anatol Manaenko
- National Health Commission Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Lili Zhou
- Department of Neurology, Chinese People's Liberation Army General Hospital, Beijing, China
| | - David S Liebeskind
- Neurovascular Imaging Research Core and University of California Los Angeles Stroke Center, University of California, Los Angeles, Los Angeles, CA, United States
| | - John H Zhang
- Department of Anesthesiology, Loma Linda University School of Medicine, Loma Linda, CA, United States
| | - Yao Li
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Qin Hu
- Central Laboratory, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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26
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Differences in Hemodynamic Alteration between Atherosclerotic Occlusive Lesions and Moyamoya Disease: A Quantitative 15O-PET Study. Diagnostics (Basel) 2021; 11:diagnostics11101820. [PMID: 34679518 PMCID: PMC8535090 DOI: 10.3390/diagnostics11101820] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 09/24/2021] [Accepted: 09/28/2021] [Indexed: 11/17/2022] Open
Abstract
To clarify the differences in hemodynamic status between atherosclerotic steno-occlusive lesions (SOL) and moyamoaya disease (MMD), hemodynamic parameters were compared using 15O-PET. Twenty-four patients with unilateral SOL (67 ± 11 y) and eighteen with MMD (33 ± 16 y) were assigned to this study. MMD patients were divided into twelve unilateral and six bilateral lesions. All patients underwent 15O-PET to measure cerebral blood flow (CBF), blood volume (CBV), oxygen extraction fraction (OEF), and metabolic rate (CMRO2). Acetazolamide was administered after the baseline scan and the second 15O-water PET was performed to evaluate cerebrovascular reactivity (CVR). For the CBF calculation in 15O-water PET, the three-weighted integral method was applied based on a one-tissue compartment model with pixel-by-pixel delay correction to measure precise CBF and arterial-to-capillary blood volume (V0). Baseline hemodynamic parameters showed significantly lower CBF, V0, and CMRO2, but greater CBV, OEF, and delay (p < 0.01) in the affected hemispheres than in the unaffected hemispheres. After ACZ administration, both hemispheres showed a significant increase in CBF (p < 0.0001), but not in V0. CVR differed significantly between the hemispheres. The arterial perfusion pressure of the functioning arterial part tended to be reduced after acetazolamide administration in patients with past neurologic events caused by hemodynamic impairment. MMD patients showed greater inactive vascular and venous volumes compared with common atherosclerotic SOL patients. The hemodynamic status of cerebral circulation may vary according to the chronic process of steno-occlusive change and the development of collateral circulation. In order to evaluate physiologic differences between the two diseases, 15O-PET with an acetazolamide challenge test is useful.
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27
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Grüter BE, Tosic L, Voglis S, Vasella F, Mutschler V, Bichsel O, Scherrer N, Regli L, Esposito G. Trends in Literature on Cerebral Bypass Surgery: A Systematic Review. Cerebrovasc Dis 2021; 51:102-113. [PMID: 34289475 DOI: 10.1159/000517415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 05/14/2021] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION Ever since the beginning of cerebral bypass surgery, the role of the bypass has been debated and indications have changed over the last 5 decades. This systematic literature research analysed all clinical studies on cerebral bypass that have been published from January 1959 to January 2020 for their year of publication, country of origin, citation index, role of and indication for bypass, bypass technique, revascularized territory, flow capacity, and title (for word cloud analysis per decade). METHODS A systematic literature research was conducted using PubMed, Web of Science, EMBASE, and SCOPUS databases. All studies that have been published until January 1, 2020, were included. RESULTS Of 6,013 identified studies, 2,585 were included in the analysis. Of these, n = 1,734 (67%) studies addressed flow-augmentation bypass and n = 701 (27%) addressed flow-preservation bypass. The most common indication reported for flow augmentation is moyamoya (n = 877, 51%), followed by atherosclerotic steno-occlusive disease (n = 753, 43%). For flow preservation, the most common indication is studies reporting on cerebral aneurysm surgery (n = 659, 94%). The increasing popularity of reporting on these bypass operations almost came to an end with the FDA approval of flow diverters for aneurysm treatment in 2011. Japan is the country with the most bypass studies (cumulatively published 933 articles), followed by the USA (630 articles) and China (232 articles). DISCUSSION/CONCLUSION Clinical studies on cerebral bypass surgery have become increasingly popular in the past decades. Since the introduction of moyamoya as a distinct pathologic entity, Asian countries in particular have a very active community regarding this disease, with an increasing number of articles published every year. Studies on bypass for chronic steno-occlusive disease peaked in the 1980s but have remained the main focus of bypass research, particularly in many European departments. The number of reports published on these bypass operations significantly decreased after the FDA approval of flow diverters for aneurysm treatment in 2011.
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Affiliation(s)
- Basil E Grüter
- Department of Neurosurgery, University Hospital Zurich, Zurich, Switzerland.,Clinical Neuroscience Center, University Hospital Zurich, Zurich, Switzerland
| | - Lazar Tosic
- Department of Neurosurgery, University Hospital Zurich, Zurich, Switzerland.,Clinical Neuroscience Center, University Hospital Zurich, Zurich, Switzerland
| | - Stefanos Voglis
- Department of Neurosurgery, University Hospital Zurich, Zurich, Switzerland.,Clinical Neuroscience Center, University Hospital Zurich, Zurich, Switzerland
| | - Flavio Vasella
- Department of Neurosurgery, University Hospital Zurich, Zurich, Switzerland.,Clinical Neuroscience Center, University Hospital Zurich, Zurich, Switzerland
| | - Valentino Mutschler
- Clinical Neuroscience Center, University Hospital Zurich, Zurich, Switzerland
| | - Oliver Bichsel
- Department of Neurosurgery, University Hospital Zurich, Zurich, Switzerland.,Clinical Neuroscience Center, University Hospital Zurich, Zurich, Switzerland
| | - Natalie Scherrer
- Clinical Neuroscience Center, University Hospital Zurich, Zurich, Switzerland.,Neurointensive Care Unit, University Hospital Zurich, Zurich, Switzerland
| | - Luca Regli
- Department of Neurosurgery, University Hospital Zurich, Zurich, Switzerland.,Clinical Neuroscience Center, University Hospital Zurich, Zurich, Switzerland
| | - Giuseppe Esposito
- Department of Neurosurgery, University Hospital Zurich, Zurich, Switzerland.,Clinical Neuroscience Center, University Hospital Zurich, Zurich, Switzerland
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28
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Baron JC. The core/penumbra model: implications for acute stroke treatment and patient selection in 2021. Eur J Neurol 2021; 28:2794-2803. [PMID: 33991152 DOI: 10.1111/ene.14916] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 05/10/2021] [Accepted: 05/10/2021] [Indexed: 12/30/2022]
Abstract
Despite major advances in prevention, ischaemic stroke remains one of the leading causes of death and disability worldwide. After centuries of nihilism and decades of failed neuroprotection trials, the discovery, initially in non-human primates and subsequently in man, that ischaemic brain tissue termed the ischaemic penumbra can be salvaged from infarction up to and perhaps beyond 24 h after stroke onset has underpinned the development of highly efficient reperfusion therapies, namely intravenous thrombolysis and endovascular thrombectomy, which have revolutionized the management of the acute stroke patient. Animal experiments have documented that how long the penumbra can survive depends not only on time elapsed since arterial occlusion ('time is brain'), but also on how severely perfusion is reduced. Novel imaging techniques allowing the penumbra and the already irreversibly damaged core in the individual subject to be mapped have documented that the time course of core growth at the expense of the penumbra widely differs from patient to patient, and hence that individual physiology should be considered in addition to time since stroke onset for decision-making. This concept has been implemented to optimize patient selection in pivotal trials of reperfusion therapies beyond 3 h after stroke onset and is now routinely applied in clinical practice, using computed tomography or magnetic resonance imaging. The notion that, in order to be both efficient and harmless, treatment should be tailored to each patient's physiological characteristics represents a radical move towards precision medicine.
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Affiliation(s)
- Jean-Claude Baron
- Institute of Psychiatry and Neuroscience of Paris (IPNP), Université de Paris, INSERM U1266, Paris, France.,GHU Paris Psychiatrie et Neurosciences, Hôpital Sainte Anne, Paris, France
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29
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Ebrahimi T, Tafakhori A, Hashemi H, Ali Oghabian M. An interictal measurement of cerebral oxygen extraction fraction in MRI-negative refractory epilepsy using quantitative susceptibility mapping. Phys Med 2021; 85:87-97. [PMID: 33984822 DOI: 10.1016/j.ejmp.2021.03.039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 03/19/2021] [Accepted: 03/30/2021] [Indexed: 11/16/2022] Open
Abstract
PURPOSE Oxygen extraction fraction (OEF) can be a factor to identify brain tissue's disability in epileptic patients. This study aimed to assess the OEF's level measurement in refractory epileptic patients (REPs) using a quantitative susceptibility mapping (QSM) method and to determine whether the OEF parameters change. METHODS QSM-OEF maps of 26 REPs and 16 healthy subjects were acquired using 3T MRI with a 64-channel coil. Eighteen regions-of-interest (ROIs) were chosen around the cortex in one appropriate slice of the brain and the mean QSM-OEF for each ROI was obtained. The correlations of QSM-OEF among different clinical characteristics of the disease, as well as between the patients and normal subjects, were also investigated. RESULTS QSM-OEF was shown to be significantly higher in REPs (44.9 ± 5.8) than that in HS (41.9 ± 6.2) (p < 0.05). Mean QSM-OEF was statistically lower in the ipsilateral side (44.5 ± 6.6) compared to the contralateral side (46.4 ± 6.8) (P < 0.01). QSM-OEF was illustrated to have a strong positive correlation with the attack duration (r = 0.6), and a moderate negative correlation with the attack frequency (r = -0.3). Using an optimized support vector machine algorithm, we could predict the disease in subjects having abnormal OEF values in the brain-selected-ROIs with sensitivity, specificity, AUC, and the precision of 0.96, 1, 0.98, and 1, respectively. CONCLUSIONS The results of this study revealed that QSM-OEF of the REPs' brain is higher than that of HS, which indicates that QSM-OEF is associated with disease activity.
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Affiliation(s)
- Tayyebeh Ebrahimi
- Department of Medical Physics and Biomedical Engineering, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Department of Neuroimaging and Analysis, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran.
| | - Abbas Tafakhori
- Iranian Center of Neurological Research (ICNR), Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran.
| | - Hassan Hashemi
- Advanced Diagnostic and Interventional Radiology Research Center (ADIR), Tehran University of Medical Sciences, Tehran, Iran.
| | - Mohammad Ali Oghabian
- Department of Medical Physics and Biomedical Engineering, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Department of Neuroimaging and Analysis, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran; Research Center for Molecular and Cellular Imaging, Tehran University of Medical Science, Tehran, Iran.
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30
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Kakuta K, Asano K, Katayama K, Ohkuma H. Assessment of cerebrovascular reserve with N-isopropyl-p-[123I]-iodoamphetamine time series analysis in patients with cerebrovascular disease. Medicine (Baltimore) 2021; 100:e25617. [PMID: 33879730 PMCID: PMC8078405 DOI: 10.1097/md.0000000000025617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 04/04/2021] [Indexed: 01/04/2023] Open
Abstract
Using N-isopropyl-p-[123I]-iodoamphetamine(123I-IMP) and single-photon emission computed tomography (SPECT), the relationship between cerebrovascular reserve and the 123I-IMP redistribution phenomenon was investigated.The 50 patients who matched the inclusion criteria were divided into control and ischemia groups, and the redistribution phenomenon was examined on resting images. The delayed images showed higher 123I-IMP accumulation in lesions in the middle cerebral artery(MCA) area and anterior cerebral artery(ACA) area, these watershed areas in the ischemia group than in the control group, confirming that the redistribution phenomenon exists with statistical significance (Wilcoxon test; control group vs ischemic group in the ACA area[P = .002], ACA-MCA watershed area(P = .014), MCA area(P = .025), and MCA-posterior cerebral artery(PCA) watershed area(P = .002). The patients were then divided into 4 types according to the Kuroda grading system, and the difference in the redistribution phenomenon was investigated between type III and the other 3 types.Compared with type I and type II, type III had a significantly lower rate of decrease in the radioisotope (RI) count, verifying the redistribution phenomenon (Student t test: type I vs type III in the ACA area(P = .008), ACA-MCA watershed area(P = .009), MCA area(P < .001), and MCA-PCA watershed area(P = .002); type II vs type III in the ACA area(P = .004), ACA-MCA watershed area(P = .2575), MCA area(P < .001), and MCA-PCA watershed area(P < .001). No significant difference between type III and type IV was observed in any area [(Student t test: type III vs type IV in the ACA area(P = .07), ACA-MCA watershed area(P = .38), MCA area(P = .05), and MCA-PCA watershed area(P = .24)].The redistribution phenomenon is associated with resting cerebral blood flow (CBF), but not necessarily with cerebral vascular reactivity (CVR).
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31
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See AP, Charbel FT. Bypass for flow-augmentation in atherosclerotic carotid occlusion: a review of the literature and career experience. J Neurosurg Sci 2021; 65:305-321. [PMID: 33709658 DOI: 10.23736/s0390-5616.21.05094-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Atherosclerosis of the internal carotid artery and intracranial vessels can compromise cerebral hemodynamics and cause stroke. Cerebral bypass has a half-century history in augmenting or replacing blood flow the brain. Several trials have investigated various applications of cerebral bypass in flow augmentation for atherosclerotic disease. This review discusses the clinical science of cerebrovascular atherosclerosis to provide the context in which cerebral bypass is currently applied. This includes prior clinical trials, ongoing clinical trials, and consensus guidelines, and is complemented by studies in the physiologic science of cerebrovascular flow. The scientific background is supplemented by the description of the technical art of bypass surgery based on a three-decade experience. Successful application of cerebral bypass to augment flow in atherosclerotic cerebrovascular disease requires correct diagnosis of compromised hemodynamic reserve refractory to medical optimization and an appropriate matching of bypass flow with cerebral demand.
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Kaczmarz S, Göttler J, Petr J, Hansen MB, Mouridsen K, Zimmer C, Hyder F, Preibisch C. Hemodynamic impairments within individual watershed areas in asymptomatic carotid artery stenosis by multimodal MRI. J Cereb Blood Flow Metab 2021; 41:380-396. [PMID: 32237952 PMCID: PMC7812517 DOI: 10.1177/0271678x20912364] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Improved understanding of complex hemodynamic impairments in asymptomatic internal carotid artery stenosis (ICAS) is crucial to better assess stroke risks. Multimodal MRI is ideal for measuring brain hemodynamics and has the potential to improve diagnostics and treatment selections. We applied MRI-based perfusion and oxygenation-sensitive imaging in ICAS with the hypothesis that the sensitivity to hemodynamic impairments will improve within individual watershed areas (iWSA). We studied cerebral blood flow (CBF), cerebrovascular reactivity (CVR), relative cerebral blood volume (rCBV), relative oxygen extraction fraction (rOEF), oxygen extraction capacity (OEC) and capillary transit-time heterogeneity (CTH) in 29 patients with asymptomatic, unilateral ICAS (age 70.3 ± 7.0 y) and 30 age-matched healthy controls. In ICAS, we found significant impairments of CBF, CVR, rCBV, OEC, and CTH (strongest lateralization ΔCVR = -24%), but not of rOEF. Although the spatial overlap of compromised hemodynamic parameters within each patient varied in a complex manner, most pronounced changes of CBF, CVR and rCBV were detected within iWSAs (strongest effect ΔCVR = +117%). At the same time, CTH impairments were iWSA independent, indicating widespread dysfunction of capillary-level oxygen diffusivity. In summary, complementary MRI-based perfusion and oxygenation parameters offer deeper perspectives on complex microvascular impairments in individual patients. Furthermore, knowledge about iWSAs improves the sensitivity to hemodynamic impairments.
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Affiliation(s)
- Stephan Kaczmarz
- Department of Neuroradiology, School of Medicine, Technical University of Munich (TUM), Munich, Germany.,TUM Neuroimaging Center (TUM-NIC), Technical University of Munich (TUM), Munich, Germany.,MRRC, Yale University, New Haven, CT, USA
| | - Jens Göttler
- Department of Neuroradiology, School of Medicine, Technical University of Munich (TUM), Munich, Germany.,TUM Neuroimaging Center (TUM-NIC), Technical University of Munich (TUM), Munich, Germany.,MRRC, Yale University, New Haven, CT, USA.,Department of Radiology, School of Medicine, Technical University of Munich (TUM), Munich, Germany
| | - Jan Petr
- PET Center, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - Mikkel Bo Hansen
- Center of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark
| | - Kim Mouridsen
- Center of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark
| | - Claus Zimmer
- Department of Neuroradiology, School of Medicine, Technical University of Munich (TUM), Munich, Germany
| | | | - Christine Preibisch
- Department of Neuroradiology, School of Medicine, Technical University of Munich (TUM), Munich, Germany.,TUM Neuroimaging Center (TUM-NIC), Technical University of Munich (TUM), Munich, Germany.,Clinic for Neurology, School of Medicine, Technical University of Munich (TUM), Munich, Germany
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Abstract
The discovery that brain tissue could potentially be salvaged from ischaemia due to stroke, has led to major advances in the development of therapies for ischemic stroke. In this review, we detail the advances in the understanding of this area termed the ischaemic penumbra, from its discovery to the evolution of imaging techniques, and finally some of the treatments developed. Evolving from animal studies from the 70s and 80s and translated to clinical practice, the field of ischemic reperfusion therapy has largely been guided by an array of imaging techniques developed to positively identify the ischemic penumbra, including positron emission tomography, computed tomography and magnetic resonance imaging. More recently, numerous penumbral identification imaging studies have allowed for a better understanding of the progression of the ischaemic core at the expense of the penumbra, and identification of patients than can benefit from reperfusion therapies in the acute phase. Importantly, 40 years of critical imaging research on the ischaemic penumbra have allowed for considerable extension of the treatment time window and better patient selection for reperfusion therapy. The translation of the penumbra concept into routine clinical practice has shown that "tissue is at least as important as time."
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Affiliation(s)
- Charlotte M Ermine
- Florey Institute of Neuroscience and Mental Health, Melbourne, Australia
| | - Andrew Bivard
- Department of Medicine, Melbourne Brain Centre at The Royal Melbourne Hospital, Parkville, Australia.,Department of Neurology, Melbourne Brain Centre at The Royal Melbourne Hospital, Parkville, Australia
| | - Mark W Parsons
- Department of Medicine, Melbourne Brain Centre at The Royal Melbourne Hospital, Parkville, Australia.,Department of Neurology, Melbourne Brain Centre at The Royal Melbourne Hospital, Parkville, Australia
| | - Jean-Claude Baron
- Institute of Psychiatry and Neuroscience of Paris (IPNP), Université de Paris, Paris, France.,GHU Paris Psychiatrie et Neurosciences, Hôpital Sainte Anne, Paris, France
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Jiang H, Zhang Y, Pang J, Qiu HC, Liu AF, Li C, Zhou J, Jin M, Man F, Jiang WJ. Interactive effect of susceptibility-diffusion mismatch and recanalization status on clinical outcome in large vessel occlusion stroke. J Stroke Cerebrovasc Dis 2020; 29:105072. [PMID: 32807474 DOI: 10.1016/j.jstrokecerebrovasdis.2020.105072] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 06/05/2020] [Accepted: 06/15/2020] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVE To investigate the interactive effect of susceptibility-diffusion mismatch and recanalization status on clinical outcome in patients with acute ischemic stroke due to large vessel occlusion. METHODS In this prospective study, consecutive ischemic stroke patients admitted within 24 h from symptom onset underwent emergency multimodal MRI at admission, including diffusion-weighted imaging (DWI), susceptibility-weighted imaging (SWI), and time-of-flight magnetic resonance angiography (TOF-MRA). Patients with large vessel occlusion within the anterior circulation were recruited. Follow-up MRI was performed within 24 h after recanalization therapy (intravenous thrombolysis, endovascular therapy, or both). Multivariable logistic regression analysis was performed to estimate the interaction between SWI-DWI mismatch score and recanalization status on clinical outcome. RESULTS A total of 90 patients were enrolled. A multiplicative interaction between SWI-DWI mismatch score and recanalization status on clinical outcome was observed (P=0.037). The interaction term "SWI-DWI mismatch score × successful recanalization" was significantly associated with favorable outcome (modified Rankin Scale score of 0-2 at 90 days; adjusted odds ratio [aOR], 2.162; 95% confidence interval [CI], 1.046-4.468). Stratified analysis showed that the likelihood of favorable outcome increased with the increase of SWI-DWI mismatch score in the successful recanalization group (OR, 2.140; 95% CI, 1.376-3.326), while there was no significant relationship between SWI-DWI mismatch score and clinical outcome in the unsuccessful recanalization group (OR, 1.212; 95% CI, 0.933-1.574). CONCLUSIONS The effects of SWI-DWI mismatch and recanalization status on clinical outcome were realized through their interaction. In anterior circulation stroke due to large vessel occlusion, patients with both high SWI-DWI mismatch scores and successful recanalization were more likely to achieve a favorable outcome, while patients with unsuccessful recanalization, or with successful recanalization but low SWI-DWI mismatch scores, were less likely to have a good prognosis.
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Affiliation(s)
- Haifei Jiang
- Medical College of Soochow University, Suzhou, China; Department of Neurology, Tongzhou People's Hospital, Nantong, China.
| | - Yiqun Zhang
- New Era Stroke Care and Research Institute, The PLA Rocket Force Characteristic Medical Center, Xinjiekou Outer Street No 16, Beijing, China.
| | - Jiangxia Pang
- Medical College of Soochow University, Suzhou, China.
| | - Han-Cheng Qiu
- New Era Stroke Care and Research Institute, The PLA Rocket Force Characteristic Medical Center, Xinjiekou Outer Street No 16, Beijing, China.
| | - Ao-Fei Liu
- New Era Stroke Care and Research Institute, The PLA Rocket Force Characteristic Medical Center, Xinjiekou Outer Street No 16, Beijing, China.
| | - Chen Li
- New Era Stroke Care and Research Institute, The PLA Rocket Force Characteristic Medical Center, Xinjiekou Outer Street No 16, Beijing, China.
| | - Ji Zhou
- New Era Stroke Care and Research Institute, The PLA Rocket Force Characteristic Medical Center, Xinjiekou Outer Street No 16, Beijing, China.
| | - Min Jin
- New Era Stroke Care and Research Institute, The PLA Rocket Force Characteristic Medical Center, Xinjiekou Outer Street No 16, Beijing, China.
| | - Fengyuan Man
- New Era Stroke Care and Research Institute, The PLA Rocket Force Characteristic Medical Center, Xinjiekou Outer Street No 16, Beijing, China.
| | - Wei-Jian Jiang
- Medical College of Soochow University, Suzhou, China; New Era Stroke Care and Research Institute, The PLA Rocket Force Characteristic Medical Center, Xinjiekou Outer Street No 16, Beijing, China.
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35
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Fan AP, An H, Moradi F, Rosenberg J, Ishii Y, Nariai T, Okazawa H, Zaharchuk G. Quantification of brain oxygen extraction and metabolism with [ 15O]-gas PET: A technical review in the era of PET/MRI. Neuroimage 2020; 220:117136. [PMID: 32634594 PMCID: PMC7592419 DOI: 10.1016/j.neuroimage.2020.117136] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 06/15/2020] [Accepted: 07/01/2020] [Indexed: 12/31/2022] Open
Abstract
Oxygen extraction fraction (OEF) and the cerebral metabolic rate of oxygen (CMRO2) are key cerebral physiological parameters to identify at-risk cerebrovascular patients and understand brain health and function. PET imaging with [15O]-oxygen tracers, either through continuous or bolus inhalation, provides non-invasive assessment of OEF and CMRO2. Numerous tracer delivery, PET acquisition, and kinetic modeling approaches have been adopted to map brain oxygenation. The purpose of this technical review is to critically evaluate different methods for [15O]-gas PET and its impact on the accuracy and reproducibility of OEF and CMRO2 measurements. We perform a meta-analysis of brain oxygenation PET studies in healthy volunteers and compare between continuous and bolus inhalation techniques. We also describe OEF metrics that have been used to detect hemodynamic impairment in cerebrovascular disease. For these patients, advanced techniques to accelerate the PET scans and potential synthesis with MRI to avoid arterial blood sampling would facilitate broader use of [15O]-oxygen PET for brain physiological assessment.
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Affiliation(s)
- Audrey P Fan
- Department of Radiology, Stanford University, Stanford, CA, USA; Department of Biomedical Engineering and Department of Neurology, University of California Davis, Davis, CA, USA.
| | - Hongyu An
- Department of Radiology, Washington University in St. Louis, St. Louis, MO, USA
| | - Farshad Moradi
- Department of Radiology, Stanford University, Stanford, CA, USA
| | | | - Yosuke Ishii
- Department of Radiology, Stanford University, Stanford, CA, USA; Department of Neurosurgery, Tokyo Medical and Dental University, Tokyo, Japan
| | - Tadashi Nariai
- Department of Neurosurgery, Tokyo Medical and Dental University, Tokyo, Japan
| | - Hidehiko Okazawa
- Biomedical Imaging Research Center, University of Fukui, Fukui, Japan
| | - Greg Zaharchuk
- Department of Radiology, Stanford University, Stanford, CA, USA
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36
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Baron JC. The effect of changing arterial blood pressure and carbon dioxide on cerebral blood flow. J Neurol Neurosurg Psychiatry 2020; 91:678-679. [PMID: 32213569 DOI: 10.1136/jnnp-2019-322432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 02/13/2020] [Accepted: 03/09/2020] [Indexed: 11/03/2022]
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37
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Scutelnic A, Mordasini P, Bervini D, El-Koussy M, Heldner MR. Management of Symptomatic Intracranial Atherosclerotic Stenosis. Curr Treat Options Neurol 2020. [DOI: 10.1007/s11940-020-00626-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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38
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Kaczmarz S, Hyder F, Preibisch C. Oxygen extraction fraction mapping with multi-parametric quantitative BOLD MRI: Reduced transverse relaxation bias using 3D-GraSE imaging. Neuroimage 2020; 220:117095. [PMID: 32599265 PMCID: PMC7730517 DOI: 10.1016/j.neuroimage.2020.117095] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 06/11/2020] [Accepted: 06/18/2020] [Indexed: 01/22/2023] Open
Abstract
Magnetic resonance imaging (MRI)-based quantification of the blood-oxygenation-level-dependent (BOLD) effect allows oxygen extraction fraction (OEF) mapping. The multi-parametric quantitative BOLD (mq-BOLD) technique facilitates relative OEF (rOEF) measurements with whole brain coverage in clinically applicable scan times. Mq-BOLD requires three separate scans of cerebral blood volume and transverse relaxation rates measured by gradient-echo (1/T2*) and spin-echo (1/T2). Although the current method is of clinical merit in patients with stroke, glioma and internal carotid artery stenosis (ICAS), there are relaxation measurement artefacts that impede the sensitivity of mq-BOLD and artificially elevate reported rOEF values. We posited that T2-related biases caused by slice refocusing imperfections during rapid 2D-GraSE (Gradient and Spin Echo) imaging can be reduced by applying 3D-GraSE imaging sequences, because the latter requires no slice selective pulses. The removal of T2-related biases would decrease overestimated rOEF values measured by mq-BOLD. We characterized effects of T2-related bias in mq-BOLD by comparing the initially employed 2D-GraSE and two proposed 3D-GraSE sequences to multiple single spin-echo reference measurements, both in vitro and in vivo. A phantom and 25 participants, including young and elderly healthy controls as well as ICAS-patients, were scanned. We additionally proposed a procedure to reliably identify and exclude artefact affected voxels. In the phantom, 3D-GraSE derived T2 values had 57% lower deviation from the reference. For in vivo scans, the formerly overestimated rOEF was reduced by −27% (p < 0.001). We obtained rOEF = 0.51, which is much closer to literature values from positron emission tomography (PET) measurements. Furthermore, increased sensitivity to a focal rOEF elevation in an ICAS-patient was demonstrated. In summary, the application of 3D-GraSE improves the mq-BOLD-based rOEF quantification while maintaining clinically feasible scan times. Thus, mq-BOLD with non-slice selective T2 imaging is highly promising to improve clinical diagnostics of cerebrovascular diseases such as ICAS.
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Affiliation(s)
- Stephan Kaczmarz
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Diagnostic and Interventional Neuroradiology, Munich, Germany; Departments of Radiology & Biomedical Imaging and of Biomedical Engineering, Magnetic Resonance Research Center, Yale University, New Haven, CT, 06520, USA; Technical University of Munich, School of Medicine, Klinikum rechts der Isar, TUM Neuroimaging Center, Munich, Germany.
| | - Fahmeed Hyder
- Departments of Radiology & Biomedical Imaging and of Biomedical Engineering, Magnetic Resonance Research Center, Yale University, New Haven, CT, 06520, USA
| | - Christine Preibisch
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Diagnostic and Interventional Neuroradiology, Munich, Germany; Technical University of Munich, School of Medicine, Klinikum rechts der Isar, TUM Neuroimaging Center, Munich, Germany; Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Clinic for Neurology, Munich, Germany
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39
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Fujimoto K, Uwano I, Sasaki M, Oshida S, Tsutsui S, Yanagihara W, Fujiwara S, Kobayashi M, Kubo Y, Yoshida K, Terasaki K, Ogasawara K. Acetazolamide-Loaded Dynamic 7T MR Quantitative Susceptibility Mapping in Major Cerebral Artery Steno-Occlusive Disease: Comparison with PET. AJNR Am J Neuroradiol 2020; 41:785-791. [PMID: 32299799 DOI: 10.3174/ajnr.a6508] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 03/01/2020] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Dynamic changes in cerebrovascular reactivity after acetazolamide administration vary markedly among patients with major cerebral arterial steno-occlusive disease. MR quantitative susceptibility mapping can dynamically quantify the cerebral magnetic susceptibility. The purpose of this study was to determine whether dynamic changes in susceptibility after administration of acetazolamide on 7T quantitative susceptibility mapping are associated with pre-existing states of CBV and the cerebral metabolic rate of oxygen in the cerebral hemispheres with major cerebral arterial steno-occlusive disease. MATERIALS AND METHODS Sixty-five patients underwent 7T MR imaging at baseline and at 5, 10, 15, and 20 minutes after acetazolamide administration. Differences between the susceptibility of venous structures and surrounding brain tissue were calculated in the quantitative susceptibility mapping images. Susceptibility differences at 5, 10, 15, and 20 minutes after acetazolamide administration relative to baseline were calculated in 97 cerebral hemispheres with major cerebral arterial steno-occlusive disease. CBV and the cerebral metabolic rate of oxygen were also calculated using 15O-gas PET in the resting state. RESULTS Dynamic changes of susceptibility after acetazolamide administration were classified into 3 patterns: abnormally increasing 5 or 10 minutes after acetazolamide administration; abnormally decreasing within 20 minutes after acetazolamide administration; and remaining unchanged after acetazolamide administration. CBV was significantly greater in the first pattern than in the latter 2. The cerebral metabolic rate of oxygen differed significantly in descending order from the first to middle to last pattern. CONCLUSIONS Dynamic changes of susceptibility after acetazolamide administration on 7T MR quantitative susceptibility mapping are associated with pre-existing states of CBV and the cerebral metabolic rate of oxygen in major cerebral arterial steno-occlusive disease.
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Affiliation(s)
- K Fujimoto
- From the Department of Neurosurgery (K.F., S.O., S.T., W.Y., S.F., M.K., Y.K., K.Y., K.O.)
| | - I Uwano
- Division of Ultrahigh Field MRI, Institute for Biomedical Sciences (I.U., M.S.)
| | - M Sasaki
- Division of Ultrahigh Field MRI, Institute for Biomedical Sciences (I.U., M.S.)
| | - S Oshida
- From the Department of Neurosurgery (K.F., S.O., S.T., W.Y., S.F., M.K., Y.K., K.Y., K.O.)
| | - S Tsutsui
- From the Department of Neurosurgery (K.F., S.O., S.T., W.Y., S.F., M.K., Y.K., K.Y., K.O.)
| | - W Yanagihara
- From the Department of Neurosurgery (K.F., S.O., S.T., W.Y., S.F., M.K., Y.K., K.Y., K.O.)
| | - S Fujiwara
- From the Department of Neurosurgery (K.F., S.O., S.T., W.Y., S.F., M.K., Y.K., K.Y., K.O.)
| | - M Kobayashi
- From the Department of Neurosurgery (K.F., S.O., S.T., W.Y., S.F., M.K., Y.K., K.Y., K.O.)
| | - Y Kubo
- From the Department of Neurosurgery (K.F., S.O., S.T., W.Y., S.F., M.K., Y.K., K.Y., K.O.)
| | - K Yoshida
- From the Department of Neurosurgery (K.F., S.O., S.T., W.Y., S.F., M.K., Y.K., K.Y., K.O.)
| | - K Terasaki
- Cyclotron Research Center (K.T.), Iwate Medical University School of Medicine, Morioka, Japan
| | - K Ogasawara
- From the Department of Neurosurgery (K.F., S.O., S.T., W.Y., S.F., M.K., Y.K., K.Y., K.O.),
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40
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Fan AP, Khalil AA, Fiebach JB, Zaharchuk G, Villringer A, Villringer K, Gauthier CJ. Elevated brain oxygen extraction fraction measured by MRI susceptibility relates to perfusion status in acute ischemic stroke. J Cereb Blood Flow Metab 2020; 40:539-551. [PMID: 30732551 PMCID: PMC7026852 DOI: 10.1177/0271678x19827944] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Recent clinical trials of new revascularization therapies in acute ischemic stroke have highlighted the importance of physiological imaging to identify optimal treatments for patients. Oxygen extraction fraction (OEF) is a hallmark of at-risk tissue in stroke, and can be quantified from the susceptibility effect of deoxyhemoglobin molecules in venous blood on MRI phase scans. We measured OEF within cerebral veins using advanced quantitative susceptibility mapping (QSM) MRI reconstructions in 20 acute stroke patients. Absolute OEF was elevated in the affected (29.3 ± 3.4%) versus the contralateral hemisphere (25.5 ± 3.1%) of patients with large diffusion-perfusion lesion mismatch (P = 0.032). In these patients, OEF negatively correlated with relative CBF measured by dynamic susceptibility contrast MRI (P = 0.004), suggesting compensation for reduced flow. Patients with perfusion-diffusion match or no hypo-perfusion showed less OEF difference between hemispheres. Nine patients received longitudinal assessment and showed OEF ratio (affected to contralateral) of 1.2 ± 0.1 at baseline that normalized (decreased) to 1.0 ± 0.1 at follow-up three days later (P = 0.03). Our feasibility study demonstrates that QSM MRI can non-invasively quantify OEF in stroke patients, relates to perfusion status, and is sensitive to OEF changes over time. Clinical trial registration: Longitudinal MRI examinations of patients with brain ischemia and blood brain barrier permeability; clinicaltrials.org :NCT02077582.
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Affiliation(s)
- Audrey P Fan
- Department of Radiology, Stanford University, Stanford, CA, USA
| | - Ahmed A Khalil
- Center for Stroke Research Berlin, Charité Universitätsmedizin Berlin, Berlin, Germany.,Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.,Berlin School of Mind and Brain, Humboldt-Universitaet zu Berlin, Berlin, Germany
| | - Jochen B Fiebach
- Center for Stroke Research Berlin, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Greg Zaharchuk
- Department of Radiology, Stanford University, Stanford, CA, USA
| | - Arno Villringer
- Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.,Berlin School of Mind and Brain, Humboldt-Universitaet zu Berlin, Berlin, Germany
| | - Kersten Villringer
- Center for Stroke Research Berlin, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Claudine J Gauthier
- Department of Physics, Concordia University, Montreal, Canada.,Montreal Heart Institute, Montreal, Canada
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41
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Yamauchi H, Kagawa S, Takahashi M, Kusano K, Okuyama C. Selective neuronal damage and blood pressure in atherosclerotic major cerebral artery disease. J Neurol Neurosurg Psychiatry 2019; 90:975-980. [PMID: 31127015 PMCID: PMC6820160 DOI: 10.1136/jnnp-2019-320326] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 04/02/2019] [Accepted: 04/05/2019] [Indexed: 11/04/2022]
Abstract
OBJECTIVE In patients with atherosclerotic major cerebral artery disease, low blood pressure might impair cerebral perfusion, thereby exacerbate the risk of selective neuronal damage. The purpose of this retrospective study was to determine whether low blood pressure at follow-up is associated with increased selective neuronal damage. METHODS We retrospectively analysed data from 76 medically treated patients with atherosclerotic internal carotid artery or middle cerebral artery disease with no ischaemic episodes on a follow-up of 6 months or more. All patients had measurements of the distribution of central benzodiazepine receptors twice using positron emission tomography and 11C-flumazenil. Using three-dimensional stereotactic surface projections, we quantified abnormal decreases in the benzodiazepine receptors of the cerebral cortex within the middle cerebral artery distribution and correlated these changes in the benzodiazepine receptors index with blood pressure values at follow-up examinations. RESULTS The changes in the benzodiazepine receptor index during follow-up (mean 27±21 months) were negatively correlated with systolic blood pressure at follow-up. The relationship between changes in benzodiazepine receptor index and systolic blood pressure was different among patients with and without decreased cerebral blood flow at baseline (interaction, p<0.005). Larger increases in benzodiazepine receptor index (neuronal damage) were observed at lower systolic blood pressure levels in patients with decreased cerebral blood flow than in patients without such decreases. CONCLUSION In patients without ischaemic stroke episodes at follow-up but with decreased cerebral blood flow due to arterial disease, low systolic blood pressure at follow-up may be associated with increased selective neuronal damage.
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Affiliation(s)
- Hiroshi Yamauchi
- Division of PET Imaging, Shiga Medical Center Research Institute, Moriyama, Japan
| | - Shinya Kagawa
- Division of PET Imaging, Shiga Medical Center Research Institute, Moriyama, Japan
| | - Masaaki Takahashi
- Division of PET Imaging, Shiga Medical Center Research Institute, Moriyama, Japan
| | - Kuninori Kusano
- Division of PET Imaging, Shiga Medical Center Research Institute, Moriyama, Japan
| | - Chio Okuyama
- Division of PET Imaging, Shiga Medical Center Research Institute, Moriyama, Japan
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42
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McLeod D. Misery Perfusion, Diffusive Oxygen Shunting and Interarterial Watershed Infarction Underlie Oxygenation-Based Hypoperfusion Maculopathy. Am J Ophthalmol 2019; 205:153-164. [PMID: 30905727 DOI: 10.1016/j.ajo.2019.03.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 03/06/2019] [Accepted: 03/09/2019] [Indexed: 11/16/2022]
Abstract
PURPOSE To describe and explain the entire range of acute ischemic macular damage that follows panretinal hypoperfusion from central retinal artery or vein occlusion. DESIGN Perspective article. METHODS To correlate the fundoscopic, fluorescein angiographic, oximetric, and optical coherence tomographic (OCT) features developing within the posterior inner retina following incremental reductions in arteriovenous perfusion pressure across the retinal circulation. RESULTS The spectrum of acute oxygenation-based hypoperfusion maculopathy (OHM) is consistent with that predictable from a modified Krogh cylinder model of tissue oxygenation. Diffusive oxygen shunting plays a significant role in the "artery-dominated" generation of ischemic signs during misery perfusion. Three major grades of OHM severity can be discerned according to the predominant oxygenation status of ganglion cells within the superficial inner retina, whether this is normoxic (OHM1), hypoxic (OHM2), or anoxic (OHM3). Densely opaque axoplasmic sentinels are arranged along normoxic/hypoxic interfaces in OHM2. In OHM1 and OHM2, relative hypermetabolism and interarterial watershed infarction of fundal interneurons (WIFI) underpin subtle middle-retinal opacification with periarterial sparing. The fundal signs are optimally displayed en face using autofluorescence imaging whereas cross-sectional OCT reveals Paques' plaque formation. CONCLUSIONS An exquisite and supremely accessible exhibition of classical oxygen physiopathology unfolds in eyes with panretinal hypoperfusion courtesy of the transparent ocular media and the pattern of macular neuroretinal opacification that evolves as upstream tissues extract oxygen to the detriment of tissues downstream. Recent attempts to overrule the simple conceptual framework embodied in WIFI have no plausible anatomical nor physiological basis. Overreliance on OCT can result in misdiagnosis.
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Affiliation(s)
- David McLeod
- Academic Department of Ophthalmology, Manchester Royal Eye Hospital, Manchester University National Health Service Foundation Trust, and Centre for Ophthalmology and Vision Research, Institute of Human Development, University of Manchester, Manchester, United Kingdom.
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43
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Stotesbury H, Kawadler JM, Hales PW, Saunders DE, Clark CA, Kirkham FJ. Vascular Instability and Neurological Morbidity in Sickle Cell Disease: An Integrative Framework. Front Neurol 2019; 10:871. [PMID: 31474929 PMCID: PMC6705232 DOI: 10.3389/fneur.2019.00871] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 07/26/2019] [Indexed: 12/20/2022] Open
Abstract
It is well-established that patients with sickle cell disease (SCD) are at substantial risk of neurological complications, including overt and silent stroke, microstructural injury, and cognitive difficulties. Yet the underlying mechanisms remain poorly understood, partly because findings have largely been considered in isolation. Here, we review mechanistic pathways for which there is accumulating evidence and propose an integrative systems-biology framework for understanding neurological risk. Drawing upon work from other vascular beds in SCD, as well as the wider stroke literature, we propose that macro-circulatory hyper-perfusion, regions of relative micro-circulatory hypo-perfusion, and an exhaustion of cerebral reserve mechanisms, together lead to a state of cerebral vascular instability. We suggest that in this state, tissue oxygen supply is fragile and easily perturbed by changes in clinical condition, with the potential for stroke and/or microstructural injury if metabolic demand exceeds tissue oxygenation. This framework brings together recent developments in the field, highlights outstanding questions, and offers a first step toward a linking pathophysiological explanation of neurological risk that may help inform future screening and treatment strategies.
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Affiliation(s)
- Hanne Stotesbury
- Developmental Neurosciences, UCL Great Ormond Institute of Child Health, London, United Kingdom
| | - Jamie M Kawadler
- Developmental Neurosciences, UCL Great Ormond Institute of Child Health, London, United Kingdom
| | - Patrick W Hales
- Developmental Neurosciences, UCL Great Ormond Institute of Child Health, London, United Kingdom
| | - Dawn E Saunders
- Developmental Neurosciences, UCL Great Ormond Institute of Child Health, London, United Kingdom.,Department of Radiology, Great Ormond Hospital, London, United Kingdom
| | - Christopher A Clark
- Developmental Neurosciences, UCL Great Ormond Institute of Child Health, London, United Kingdom
| | - Fenella J Kirkham
- Developmental Neurosciences, UCL Great Ormond Institute of Child Health, London, United Kingdom.,Clinical and Experimental Sciences, University of Southampton, Southampton, United Kingdom.,Department of Child Health, University Hospital Southampton, Southampton, United Kingdom.,Department of Paediatric Neurology, Kings College Hospital NHS Foundation Trust, London, United Kingdom
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44
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Miyata M, Kakeda S, Kudo K, Iwata S, Tanaka Y, Wang Y, Korogi Y. Evaluation of oxygen extraction fraction in systemic lupus erythematosus patients using quantitative susceptibility mapping. J Cereb Blood Flow Metab 2019; 39:1648-1658. [PMID: 29547080 PMCID: PMC6681530 DOI: 10.1177/0271678x18764829] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The purposes of this study are to assess the oxygen extraction fraction (OEF) changes on MRI-based quantitative susceptibility mapping (QSM) in systemic lupus erythematosus (SLE) patients and to determine whether QSM-OEF is associated with disease activity in SLE. We enrolled 42 SLE patients and 20 healthy subjects (HS) who had no pathologies on conventional brain MRI. Disease activity was assessed using SLE Disease Activity Index (SLEDAI). For the measurement of QSM-OEF, QSM data were analysed using the Perfusion Mismatch Analyzer software program. Spearman's or Pearson's correlation coefficients were calculated, and independent predictors were identified through a multiple linear regression analysis. QSM-OEF was significantly higher in SLE than that in HS (51.3 ± 10.1 vs. 40.5 ± 3.7, p < 0.001). QSM-OEF was positively correlated with SLEDAI and the presence of neuropsychiatric symptom (NPS) scores (ρ = 0.663, p < 0.001 and ρ = 0.340, p = 0.028). At multiple linear regression analysis, SLEDAI and NPS were independently associated with QSM-OEF (standardized β = 0.426, p = 0.016 and standardized β = 6.148, p = 0.029). In the SLE patients, QSM-OEF is associated with disease activity, which might predict an increased risk of stroke in SLE.
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Affiliation(s)
- Mari Miyata
- 1 Department of Radiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Shingo Kakeda
- 1 Department of Radiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Kohsuke Kudo
- 2 Department of Diagnostic and Interventional Radiology, Hokkaido University Hospital, Sapporo, Japan
| | - Shigeru Iwata
- 3 Department of the First Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Yoshiya Tanaka
- 3 Department of the First Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Yi Wang
- 4 Departments of Biomedical Engineering and Radiology, Cornell University, MedImageMetric LLC, New York, NY, USA
| | - Yukunori Korogi
- 1 Department of Radiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
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Seiler A, Kammerer S, Gühl A, Schüre JR, Deichmann R, Nöth U, Pfeilschifter W, Hattingen E, Keese M, Pilatus U, Wagner M. Revascularization of High-Grade Carotid Stenosis Restores Global Cerebral Energy Metabolism. Stroke 2019; 50:1742-1750. [PMID: 31164069 DOI: 10.1161/strokeaha.118.023559] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background and Purpose- Chronic cerebral hemodynamic impairment due to high-grade occlusive carotid disease may lead to compromised energy metabolism. This might result in chronic subtle tissue damage, even in patients without overt brain infarction. The aim of this study was to investigate hypoperfusion-related changes of cerebral energy metabolism and their potential restitution after revascularization. For this purpose, 3-dimensional 31P magnetic resonance spectroscopy and oxygenation-sensitive T2' magnetic resonance imaging were used (with 1/T2'=1/T2*-1/T2), which were expected to cross-validate each other. Methods- Ten patients with unilateral high-grade carotid artery stenosis resulting in a transient ischemic attack or a nondisabling cerebral ischemia were included. Then, high-energy metabolites, intracellular pH, and oxygenation-sensitive quantitative (q)T2' values were determined in noninfarcted hypoperfused areas delineated on time-to-peak maps from perfusion-weighted imaging and in unaffected contralateral areas before and shortly after carotid stenting/endarterectomy. Repeated measures ANOVA was used to test for intervention effects. Results- Within dependent hypoperfused areas ipsilateral to the stenosis, qT2' was significantly decreased ( P<0.05) as compared to corresponding contralateral areas before carotid intervention. There was a significant effect of carotid intervention on qT2' values in both hemispheres ( P<0.001). No differences between hemispheres were found for qT2' after revascularization. Intracellular pH and qT2' values showed a significant negative relationship ( P=0.005) irrespective of time point and hemisphere. Conclusions- After revascularization of unilateral high-grade carotid stenosis, previously decreased qT2' in the dependent hypoperfused territory as marker of hypoxia reincreases not only in the dependent territory but also in corresponding contralateral brain tissue. This might indicate a restriction of the whole-brain oxygen metabolism in case of unilateral high-grade carotid stenosis and an improvement of whole-brain oxygenation after revascularization that goes beyond acute clinically apparent affection of the dependent territory. Furthermore, tissue oxygen supply seems to be closely linked to intracellular pH.
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Affiliation(s)
- Alexander Seiler
- From the Department of Neurology (A.S., W.P.), Goethe University Frankfurt, Germany
| | - Sara Kammerer
- Institute of Neuroradiology (S.K., A.G., J.R.S., E.H., U.P., M.W.), Goethe University Frankfurt, Germany
| | - Alexander Gühl
- Institute of Neuroradiology (S.K., A.G., J.R.S., E.H., U.P., M.W.), Goethe University Frankfurt, Germany
| | - Jan Rüdiger Schüre
- Institute of Neuroradiology (S.K., A.G., J.R.S., E.H., U.P., M.W.), Goethe University Frankfurt, Germany
| | - Ralf Deichmann
- Brain Imaging Center (R.D., U.N.), Goethe University Frankfurt, Germany
| | - Ulrike Nöth
- Brain Imaging Center (R.D., U.N.), Goethe University Frankfurt, Germany
| | | | - Elke Hattingen
- Institute of Neuroradiology (S.K., A.G., J.R.S., E.H., U.P., M.W.), Goethe University Frankfurt, Germany
| | - Michael Keese
- Department of Vascular Surgery (M.K.), Goethe University Frankfurt, Germany
| | - Ulrich Pilatus
- Institute of Neuroradiology (S.K., A.G., J.R.S., E.H., U.P., M.W.), Goethe University Frankfurt, Germany
| | - Marlies Wagner
- Institute of Neuroradiology (S.K., A.G., J.R.S., E.H., U.P., M.W.), Goethe University Frankfurt, Germany
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Hayashi K, Uekawa K, Kawano T, Ohmori Y, Amadatsu T, Takemoto Y, Mukasa A. Cortical Venous Reddening Predicts Remote Cerebral Infarction Post Superficial Temporal Artery-Middle Cerebral Artery Bypass in Atherosclerotic Occlusive Cerebrovascular Disease. World Neurosurg 2019; 127:e864-e872. [PMID: 30954735 DOI: 10.1016/j.wneu.2019.03.287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 03/27/2019] [Accepted: 03/28/2019] [Indexed: 11/24/2022]
Abstract
BACKGROUND The superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis (STA-MCA bypass) currently is performed to prevent atherosclerotic occlusive cerebrovascular disease. However, the benefits of the bypass surgery remain controversial. To ensure consistent surgical benefits, understanding the mechanisms of perioperative cerebral infarction (CI) is required. Moreover, appropriate patient selection procedures must be determined to decrease the rate of perioperative stroke. We retrospectively investigated patients who underwent bypass surgery at our institution and determined that the patients who presented with cortical venous reddening after anastomosis during the surgery developed perioperative CI. METHODS A total of 45 consecutive patients who underwent bypass surgery were retrospectively investigated. Twenty-five of the 45 patients underwent bypass for atherosclerotic occlusion or stenosis of the internal carotid artery or middle cerebral artery. Preoperative iodine-123-N-isopropyl-iodoamphetamine single-photon emission computed tomography was performed with and without acetazolamide administration. Change in color of the cortical veins was observed on recorded surgical videos, and its correlation with perioperative CI was investigated. RESULTS We experienced 2 cases of perioperative extensive CI at a region remote from the site of anastomosis. In both cases, retrospective investigation of surgical videos demonstrated reddening of cortical veins soon after the anastomosis procedure. Of all 45 patients, postoperative CI and venous reddening were observed in only these 2 cases. CONCLUSIONS We determined that patients presenting with cortical venous reddening after anastomosis developed perioperative CI. Cortical venous reddening may be an important predictor for the occurrence of CI after STA-MCA bypass surgery for patients with atherosclerotic occlusive cerebrovascular disease.
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Affiliation(s)
- Kenyu Hayashi
- Department of Neurosurgery, Kumamoto University School of Medicine, Honjo, Kumamoto, Japan
| | - Ken Uekawa
- Department of Neurosurgery, Saiseikai Kumamoto Hospital, Chikami, Kumamoto, Japan
| | - Takayuki Kawano
- Department of Neurosurgery, Kumamoto University School of Medicine, Honjo, Kumamoto, Japan.
| | - Yuki Ohmori
- Department of Neurosurgery, Kumamoto University School of Medicine, Honjo, Kumamoto, Japan
| | - Toshihiro Amadatsu
- Department of Neurosurgery, Kumamoto University School of Medicine, Honjo, Kumamoto, Japan
| | - Yushin Takemoto
- Department of Neurosurgery, Kumamoto University School of Medicine, Honjo, Kumamoto, Japan
| | - Akitake Mukasa
- Department of Neurosurgery, Kumamoto University School of Medicine, Honjo, Kumamoto, Japan
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Eker OF, Ameli R, Makris N, Jurkovic T, Montigon O, Barbier EL, Cho TH, Nighoghossian N, Berthezène Y. MRI Assessment of Oxygen Metabolism and Hemodynamic Status in Symptomatic Intracranial Atherosclerotic Stenosis: A Pilot Study. J Neuroimaging 2019; 29:467-475. [DOI: 10.1111/jon.12615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 03/14/2019] [Accepted: 03/17/2019] [Indexed: 10/27/2022] Open
Affiliation(s)
- Omer F. Eker
- Department of NeuroradiologyHospices Civils de Lyon Bron France
- CREATIS CNRS UMR 5220, INSERM U1044 Villeurbanne cedex France
| | - Roxana Ameli
- Department of NeuroradiologyHospices Civils de Lyon Bron France
| | - Nikolaos Makris
- CREATIS CNRS UMR 5220, INSERM U1044 Villeurbanne cedex France
| | - Thomas Jurkovic
- Department of NeuroradiologyHospices Civils de Lyon Bron France
| | - Olivier Montigon
- INSERM U1216Grenoble Institut des Neurosciences La Tronche France
| | - Emmanuel L. Barbier
- INSERM U1216Grenoble Institut des Neurosciences La Tronche France
- Université Grenoble Alpes Saint‐Martin‐d'Hères France
| | - Tae Hee Cho
- CREATIS CNRS UMR 5220, INSERM U1044 Villeurbanne cedex France
| | | | - Yves Berthezène
- Department of NeuroradiologyHospices Civils de Lyon Bron France
- CREATIS CNRS UMR 5220, INSERM U1044 Villeurbanne cedex France
- Department of Vascular Neurology, Hospices Civils de LyonHôpital Pierre Wertheimer Bron France
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Heiss WD, Zaro-Weber O. Extension of therapeutic window in ischemic stroke by selective mismatch imaging. Int J Stroke 2019; 14:351-358. [DOI: 10.1177/1747493019840936] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The concept of the ischemic penumbra was formulated on the basis of animal experiments showing functional impairment and electrophysiologic disturbances with decreasing flow to the brain below defined values (the threshold for function) and irreversible tissue damage with blood supply further decreased (the threshold for infarction). The perfusion range between these thresholds was termed the “penumbra,” and restitution of flow above the functional threshold was able to reverse the deficits without permanent damage. In further experiments, the dependency of the development of irreversible lesions on the interaction of the severity and the duration of critically reduced blood flow was established, proving that the lower the flow, the shorter the time for efficient reperfusion. As a consequence, infarction develops from the core of ischemia to the areas of less severe hypoperfusion. The translation of this experimental concept as the basis for the efficient treatment of stroke requires methods by which regional flow and energy metabolism can be repeatedly investigated to demonstrate penumbra tissue, which can benefit from therapeutic interventions. Positron emission tomography allows the quantification of regional cerebral blood flow, the regional oxygen extraction fraction, and the regional metabolic rate for oxygen. With these variables, clear definitions of irreversible tissue damage and of critically hypoperfused but potentially salvageable tissue (i.e. the penumbra) in stroke patients can be achieved. However, positron emission tomography is a research tool, and its complex logistics limit clinical routine applications. Perfusion-weighted or diffusion-weighted magnetic resonance imaging is a widely applicable clinical tool, and the “mismatch” between perfusion-weighted and diffusion-weighted abnormalities serves as an indicator of the penumbra. Also computed tomography angiography and computed tomography perfusion imaging can be used to detect areas suspicious of penumbra. The findings with both methods should be validated by positron emission tomography measurements. Several studies included the selection of patients for intravenous thrombolysis on the basis of a perfusion-weighted imaging–diffusion-weighted imaging mismatch or computed tomography perfusion studies. A meta-analysis of several mismatch-based thrombolysis studies of delayed treatment from the DIAS, DIAS-2, DEDAS, EPITHET, and DEFUSE trials revealed increased recanalization. However, this analysis did not confirm an improvement in clinical outcome with delayed thrombolysis. Randomized controlled trials that did enroll patients based on the presence of a target mismatch on multimodal imaging demonstrated a higher benefit of revascularization treatment by comparison with those who did not and demonstrated for the first time that revascularization treatment for occlusion of an internal carotid artery (ICA) or a proximal middle cerebral artery (MCA) was still beneficial from 6 to 24 h after onset among patients in whom the clinical examination and the multimodal brain imaging indicate a persistent penumbra. On this background, the yield of imaging for the selection of patients for a revascularization therapy will be discussed.
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Affiliation(s)
- Wolf-Dieter Heiss
- Max Planck Institute for Metabolism Research, Cologne, Germany
- Max Planck Institute for Neurological Research, Cologne, Germany
| | - Olivier Zaro-Weber
- Max Planck Institute for Metabolism Research, Cologne, Germany
- Max Planck Institute for Neurological Research, Cologne, Germany
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Yamauchi H, Kagawa S, Takahashi M, Oishi N, Ono M, Higashi T. Misery perfusion and amyloid deposition in atherosclerotic major cerebral artery disease. NEUROIMAGE-CLINICAL 2019; 22:101762. [PMID: 30884364 PMCID: PMC6424140 DOI: 10.1016/j.nicl.2019.101762] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 01/08/2019] [Accepted: 03/10/2019] [Indexed: 11/18/2022]
Abstract
Although experimental studies have shown that global cerebral hypoperfusion leads to amyloid deposition in the hemisphere with carotid artery occlusion in rodents, the results of such occurrence are controversial in humans. Hence, we aim to determine whether global cerebral hypoperfusion leading to decreased blood flow relative to metabolic demand [increased oxygen extraction fraction (OEF), misery perfusion] is associated with increases in amyloid deposition in the hemisphere with atherosclerotic major cerebral artery disease in patients. We evaluated the distribution of β-amyloid plaques using positron emission tomography and a [18F]-pyridylbenzofuran derivative (18F-FPYBF-2) in 13 patients with unilateral atherosclerotic disease of the internal carotid artery (ICA) or middle cerebral artery (MCA) disease and no cortical infarction. The distribution volume ratio (DVR) of 18F- FPYBF-2 was calculated using dynamic data and Logan graphical analysis with reference tissue and was correlated with the cerebral blood flow (CBF), cerebral metabolic rate of oxygen (CMRO2), and OEF, obtained from 15O-gas PET. The mean cortical value was calculated as the mean value within the frontal, posterior cingulate, precuneus, parietal, and lateral temporal cortical regions. Significant reductions in CBF and CMRO2 and increases in OEF were found in the hemisphere ipsilateral to the arterial lesion compared with the contralateral hemisphere. There was no significant difference for 18F-FPYBF-2 DVR between hemispheres. The ipsilateral to contralateral ratio of the 18F- FPYBF-2 DVR was increased in 3 patients, while the ipsilateral to contralateral OEF ratio was increased in 4 patients. The incidence of an increased hemispheric DVR ratio was significantly higher in patients with an increased hemispheric OEF ratio (3/4) than in patients without (0/9) (p < 0.02). Although the 18F- FPYBF-2 DVR in the ipsilateral hemisphere was positively correlated with OEF after adjustment for the 18F- FPYBF-2 DVR in the contralateral hemisphere using multiple regression analysis (p < 0.05), the contribution rate of OEF was small (R2 = 5.5%). Only one of the 4 patients with an increased hemispheric OEF ratio showed amyloid positivity based on the DVR value. In atherosclerotic major cerebral artery disease, misery perfusion accompanied only small increases of amyloid deposition at best. Misery perfusion was not associated with amyloid positivity. Misery perfusion accompanied only small increases of amyloid deposition at best. Relative oxygen extraction fraction correlated with relative amyloid deposition. Misery perfusion was not associated with amyloid positivity.
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Affiliation(s)
- Hiroshi Yamauchi
- Division of PET Imaging, Shiga Medical Centre Research Institute, Moriyama, Japan.
| | - Shinya Kagawa
- Division of PET Imaging, Shiga Medical Centre Research Institute, Moriyama, Japan
| | - Masaaki Takahashi
- Division of PET Imaging, Shiga Medical Centre Research Institute, Moriyama, Japan
| | - Naoya Oishi
- Human Brain Research Center, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Masahiro Ono
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan
| | - Tatsuya Higashi
- Division of PET Imaging, Shiga Medical Centre Research Institute, Moriyama, Japan; National Institute of Radiological Sciences, National Institutes of Quantum and Radiological Science and Technology, Chiba, Japan
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Yamauchi H, Kagawa S, Takahashi M, Higashi T. Long-term hemodynamic changes and blood pressure in atherosclerotic major cerebral artery disease. J Cereb Blood Flow Metab 2019; 39:324-331. [PMID: 28820296 PMCID: PMC6365607 DOI: 10.1177/0271678x17727385] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
In patients with major cerebral artery disease, lower blood pressure might reduce blood flow in the collateral pathways, thereby impairing the growth of cerebral collaterals, inhibiting hemodynamic improvement. We evaluated the hemodynamic status twice using positron emission tomography and 15O-gas, over time, in 89 medically treated patients with atherosclerotic internal carotid artery or middle cerebral artery disease that had no ischemic episodes during follow-up (mean, 28 ± 23 months). Changes in the mean hemispheric values of hemodynamic parameters in the territory of the diseased artery at follow-up were correlated with the mean blood pressure values at the baseline and follow-up examinations. There was a positive linear relationship between the degree of hemodynamic improvement and systolic blood pressure. Patients with low systolic blood pressure (<130 mmHg) ( n = 18) showed hemodynamic deterioration as indicated by significant decreases in cerebral blood flow, cerebral blood flow/cerebral blood volume ratio, and increases in oxygen extraction fraction during follow-up. In contrast, there were no significant changes in patients without low systolic blood pressure. In patients with atherosclerotic internal carotid artery or middle cerebral artery disease and no ischemic episodes of stroke during follow-up, lower systolic blood pressure was associated with lesser hemodynamic improvement.
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Affiliation(s)
- Hiroshi Yamauchi
- 1 Division of PET Imaging, Shiga Medical Center Research Institute, Moriyama, Japan
| | - Shinya Kagawa
- 1 Division of PET Imaging, Shiga Medical Center Research Institute, Moriyama, Japan
| | - Masaaki Takahashi
- 1 Division of PET Imaging, Shiga Medical Center Research Institute, Moriyama, Japan
| | - Tatsuya Higashi
- 1 Division of PET Imaging, Shiga Medical Center Research Institute, Moriyama, Japan.,2 National Institute of Radiological Sciences, National Institutes of Quantum and Radiological Science and Technology, Chiba, Japan
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