40,661 results match your criteria cerebral perfusion


Enhancement degree of brain metastases: correlation analysis between enhanced T2 FLAIR and vascular permeability parameters of dynamic contrast-enhanced MRI.

Eur Radiol 2021 Apr 13. Epub 2021 Apr 13.

Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.

Objectives: To investigate the correlation between enhancement degrees of brain metastases on contrast-enhanced T2-fluid-attenuated inversion recovery (CE-T2 FLAIR) and vascular permeability parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).

Methods: Thirty-nine patients with brain metastases were prospectively collected. They underwent non-enhanced T2 FLAIR, DCE-MRI, CE-T2 FLAIR, and contrast-enhanced three-dimensional brain volume imaging (CE-BRAVO). Read More

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Increased heterogeneity of brain perfusion predicts the development of cerebrovascular accidents.

Medicine (Baltimore) 2021 Apr;100(15):e25557

Division of Allergy, Immunology and Rheumatology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.

Abstract: The heterogeneity of brain perfusion is related to the risk factors of thromboembolic events such as antiphospholipid syndrome. However, the effectiveness of brain perfusion heterogeneity as a marker to predict thromboembolic events has not been confirmed. Our objective was to evaluate the effectiveness of brain perfusion heterogeneity as a marker to predict the development of cerebrovascular accidents. Read More

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Successful treatment of cardiac arrest following hysteroscopic surgery using extracorporeal membrane oxygenation: A case report.

Medicine (Baltimore) 2021 Apr;100(15):e25519

Intensive Care Unit, The First Affiliated Hospital of USTC, University of Science and Technology of China, Anhui, China.

Rationale: Cardiac arrest caused by water intoxication syndrome following hysteroscopic surgery is a rare but life-threatening occurrence. Extracorporeal membrane oxygenation (ECMO) is rarely used to treat water intoxication syndrome in hysteroscopic surgery. Here, we successfully treated a patient with water intoxication syndrome following hysteroscopic surgery with ECMO. Read More

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Rapamycin restores brain vasculature, metabolism, and blood-brain barrier in an inflammaging model.

Geroscience 2021 Apr 13. Epub 2021 Apr 13.

Oklahoma Nathan Shock Center for Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.

Rapamycin (RAPA) is found to have neuro-protective properties in various neuroinflammatory pathologies, including brain aging. With magnetic resonance imaging (MRI) techniques, we investigated the effect of RAPA in a lipopolysaccharide (LPS)-induced inflammaging model in rat brains. Rats were exposed to saline (control), or LPS alone or LPS combined with RAPA treatment (via food over 6 weeks). Read More

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Increased beat-to-beat variability of cerebral microcirculatory perfusion during atrial fibrillation: a near-infrared spectroscopy study.

Europace 2021 Apr 13. Epub 2021 Apr 13.

Division of Cardiology, Department of Medical Sciences, 'Città della Salute e della Scienza di Torino' Hospital, University of Turin, Turin, Italy.

Aims: Atrial fibrillation (AFib) is associated with cognitive decline/dementia, independently from clinical strokes or transient ischaemic attacks (TIA). Recent in silico data suggested that AFib may induce transient critical haemodynamic events in the cerebral microcirculation. The aim of this study is to use non-invasive spatially resolved cerebral near-infrared spectroscopy (SRS-NIRS) to investigate in vivo beat-to-beat microcirculatory perfusion during AFib and after sinus rhythm (SR) restoration. Read More

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Delayed Endovascular Thrombectomy for Ischemic Stroke in a Young Woman with No Known Risk Factors: A Case Report.

Am J Case Rep 2021 Apr 12;22:e930291. Epub 2021 Apr 12.

University of Nevada, Reno School of Medicine, Reno, NV, USA.

BACKGROUND National guidelines and consensus statements suggest a 24-hour window for endovascular recanalization in patients presenting with acute ischemic stroke due to large-vessel occlusion. However, the safety and efficacy of extending the window for intervention remains to be definitively established. CASE REPORT A healthy 26-year-old woman presented with headache, left-sided hemiplegia, and rightward gaze palsy 2 days after a minor trauma. Read More

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Improved Cerebral Perfusion Pressure and Microcirculation by Drag Reducing Polymer-Enforced Resuscitation Fluid After Traumatic Brain Injury and Hemorrhagic Shock.

Acta Neurochir Suppl 2021 ;131:289-293

Lovelace Biomedical Research Institute, Albuquerque, NM, USA.

Hemorrhagic shock (HS) after traumatic brain injury (TBI) reduces cerebral perfusion pressure (CPP) and cerebral blood flow (CBF), increasing hypoxia and doubling mortality. Volume expansion with resuscitation fluids (RFs) for HS does not improve CBF and tissue oxygen, while hypervolemia exacerbates brain edema and elevates intracranial pressure (ICP). We tested whether drag-reducing polymers (DRPs), added to isotonic Hetastarch (HES), would improve CBF but prevent ICP increase. Read More

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January 2021

Lower Limit of Reactivity Assessed with PRx in an Experimental Setting.

Acta Neurochir Suppl 2021 ;131:275-278

Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK.

In traumatic brain injury, longer time spent with a cerebral perfusion pressure (CPP) below the pressure reactivity index (PRx)-derived lower limit of reactivity (LLR) has been shown to be statistically associated with higher mortality. We set out to scrutinise the behaviour of LLR and the methods of its estimation in individual cases by performing retrospective analysis of intracranial pressure (ICP), arterial blood pressure (ABP) and laser Doppler flow (LDF) signals recorded in nine piglets undergoing controlled, terminal hypotension. We focused on the sections of the recordings with stable experimental conditions where a clear breakpoint of LDF/CPP characteristic (LLA) could be identified. Read More

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January 2021

Plateau Waves of Intracranial Pressure: Methods for Automatic Detection and Prediction.

Acta Neurochir Suppl 2021 ;131:249-253

Faculty of Engineering, INESC-TEC and Department of Electrical and Computer Engineering, University of Porto, Porto, Portugal.

Plateau waves are recurrent phenomena observed in traumatic brain injury (TBI) patients, characterised by an increase in intracranial pressure (ICP) above 40 mmHg combined with an almost zero arterial blood pressure (ABP) variation and, hence, a decrease in cerebral perfusion pressure (CPP). A raised ICP for a long period of time, namely plateau waves, can lead to a secondary brain injury. Due to the impaired cerebral autoregulation mechanism these TBI patients present, they are admitted to neurocritical care units (NCCUs) to be under continuous multimodal monitoring, which allows a correct diagnosis for each patient. Read More

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January 2021

Spectral Cerebral Blood Volume Accounting for Noninvasive Estimation of Changes in Cerebral Perfusion Pressure in Patients with Traumatic Brain Injury.

Acta Neurochir Suppl 2021 ;131:193-199

Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, Cambridge Biomedical Campus, Addenbrooke's Hospital, University of Cambridge, Cambridge, UK.

We present the application of a new method for non-invasive cerebral perfusion pressure estimation (spectral nCPP or nCPP) accounting for changes in transcranial Doppler-derived pulsatile cerebral blood volume. Primarily, we analysed cases in which CPP was changing (delta [∆],magnitude of changes]): (1) rise during vasopressor-induced augmentation of ABP (N = 16); and (2) spontaneous changes in intracranial pressure (ICP) during plateau waves (N = 14). Secondarily, we assessed nCPP in a larger cohort in which CPP presented a wider range of values. Read More

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January 2021

Monitoring of Cerebrovascular Reactivity in Intracerebral Hemorrhage and Its Relation with Survival.

Acta Neurochir Suppl 2021 ;131:187-190

Department of Intensive Care Medicine, Centro Hospitalar São João, Porto, Portugal.

Introduction: Neuromonitoring analysis for intracerebral hemorrhage (ICH) is still rare, especially regarding vascular reactivity patterns. Our goal was to analyze neuromonitoring data and 28-day mortality for ICH patients.

Methods: Neuromonitoring records were retrospectively reviewed from a cohort of ICH patients admitted to a neurocritical care unit between 2013 and 2016. Read More

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January 2021

Optimal Cerebral Perfusion Pressure Assessed with a Multi-Window Weighted Approach Adapted for Prospective Use: A Validation Study.

Acta Neurochir Suppl 2021 ;131:181-185

Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK.

Background: Pressure reactivity index (PRx)-cerebral perfusion pressure (CPP) relationships over a given time period can be used to detect a value of CPP at which PRx shows the best autoregulation (optimal CPP, or CPPopt). Algorithms for continuous assessment of CPPopt in traumatic brain injury (TBI) patients reached the desired high yield with a multi-window approach (CPPopt_MA). However, the calculations were tested on retrospective manually cleaned datasets. Read More

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January 2021

Optimal Cerebral Perfusion Pressure Based on Intracranial Pressure-Derived Indices of Cerebrovascular Reactivity: Which One Is Better for Outcome Prediction in Moderate/Severe Traumatic Brain Injury?

Acta Neurochir Suppl 2021 ;131:173-179

Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, Addenbrooke's Hospital, University of Cambridge, Cambridge, UK.

Intracranial pressure (ICP)-derived indices of cerebrovascular reactivity (e.g., PRx, PAx, and RAC) have been developed to improve understanding of brain status from available neuromonitoring variables. Read More

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January 2021

Influence of Patient Demographics on Optimal Cerebral Perfusion Pressure Following Traumatic Brain Injury.

Acta Neurochir Suppl 2021 ;131:153-158

Department of Neuroanaesthesia, Institute of Neurological Sciences, Queen Elizabeth University Hospital, Glasgow, UK.

The relationship between optimal cerebral perfusion pressure (CPPopt) and patient characteristics has yet to be defined but could have significant implications for future guidelines recommending cerebral perfusion pressure (CPP) targets.Data from 36 traumatic brain injured patients admitted to neurological intensive care were analysed retrospectively. Linear mixed effects (LME) analysis was performed using an unadjusted-adjusted approach. Read More

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January 2021

An Update on the COGiTATE Phase II Study: Feasibility and Safety of Targeting an Optimal Cerebral Perfusion Pressure as a Patient-Tailored Therapy in Severe Traumatic Brain Injury.

Acta Neurochir Suppl 2021 ;131:143-147

Department of Intensive Care Medicine, University of Maastricht, Maastricht University Medical Centre, Maastricht, The Netherlands.

Introduction: Monitoring of cerebral autoregulation (CA) in patients with a traumatic brain injury (TBI) can provide an individual 'optimal' cerebral perfusion pressure (CPP) target (CPPopt) at which CA is best preserved. This potentially offers an individualized precision medicine approach. Retrospective data suggest that deviation of CPP from CPPopt is associated with poor outcomes. Read More

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January 2021

Impaired Autoregulation Following Resuscitation Correlates with Outcome in Pediatric Patients: A Pilot Study.

Acta Neurochir Suppl 2021 ;131:97-101

Pediatric Intensive Care Unit, University Children's Hospital of Tuebingen, Tuebingen, Germany.

In children with a traumatic brain injury, the duration of autoregulation impairment correlates with the neurological outcome. This pilot study explored whether a similar relation exists in nontraumatic hypoxic-ischemic brain injury following resuscitation.We investigated 11 children after resuscitation. Read More

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January 2021

Effects of Hyperthermia on Intracranial Pressure and Cerebral Autoregulation in Patients with an Acute Brain Injury.

Acta Neurochir Suppl 2021 ;131:71-74

Burdenko Neurosurgical Institute, Moscow, Russia.

Hyperthermia is a common detrimental condition in patients with an acute brain injury (ABI), which can worsen their prognosis and outcome. The aim of this study was to evaluate the effects of hyperthermia on intracranial pressure (ICP) and cerebral autoregulation (CA).Eight patients with ABI were studied. Read More

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January 2021

Perioperative Dynamics of Intracranial B-waves of Blood Flow Velocity in the Basal Cerebral Arteries in Patients with Brain Arteriovenous Malformation.

Acta Neurochir Suppl 2021 ;131:63-68

Johannes-Mueller Institute of Vegetative Physiology University Hospital Charité, Humboldt University of Berlin, Berlin, Germany.

Intracranial B-waves (8-30 mHz) of blood flow velocity (BFV) in the cerebral arteries are observed in various pathologies of the brain. Changes in B-waves of BFV in pathological arteriovenous shunting and "steal" syndrome remain poorly understood. The aim of this study was to evaluate the dynamics of the B-wave amplitude of BFV (BWA) in patients with an arteriovenous malformation (AVM) in the brain. Read More

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January 2021

Assessment of Cerebral Autoregulation in the Perifocal Zone of a Chronic Subdural Hematoma.

Acta Neurochir Suppl 2021 ;131:51-54

Lovelace Biomedical Research Institute, Albuquerque, NM, USA.

Introduction: The knowledge of conservative treatment modalities for a chronic subdural hematoma (CSDH) is still based on low-grade evidence. The purpose of this study was to evaluate the condition of the microcirculation and autoregulation in the perifocal CSDH zone for understanding of the mechanism of CSDH development.

Methods: Cerebral microcirculation was evaluated in patients with the aid of brain perfusion computed tomography (PCT) within the first day. Read More

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January 2021

Cerebrovascular Consequences of Elevated Intracranial Pressure After Traumatic Brain Injury.

Acta Neurochir Suppl 2021 ;131:43-48

Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK.

We compared various descriptors of cerebral hemodynamics in 517 patients with traumatic brain injury (TBI) who had, on average, elevated (>23 mmHg) or normal (<15 mmHg) intracranial pressure (ICP). In a subsample of 193 of those patients, transcranial Doppler ultrasound (TCD) recordings were made. Arterial blood pressure (ABP), cerebral blood flow velocity (CBFV), cerebral autoregulation indices based on TCD (the mean flow index (Mx; the coefficient of correlation between the the cerebral perfusion pressure CPP and flow velocity) and the autoregulation index (ARI)), and the pressure reactivity index (PRx) were compared between groups. Read More

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January 2021

Analysis of the Association Between Lung Function and Brain Tissue Oxygen Tension in Severe Traumatic Brain Injury.

Acta Neurochir Suppl 2021 ;131:27-30

Neurosciences Critical Care, University of Cambridge, Cambridge, UK.

Introduction: Low brain tissue oxygen tension (PbtO) has been shown to be an independent factor associated with unfavourable outcomes in traumatic brain injury (TBI). Although PbtO provides clinicians with an understanding of ischaemic and non-ischaemic derangements of brain physiology, the value alone can be the result of several factors, including partial arterial oxygenation pressure (PaO), haemoglobin levels (Hb) and cerebral perfusion pressure (CPP).

Methods: This chapter presents a single-centre, retrospective cohort study of 70 adult patients with severe TBI who were admitted to the Neurocritical Care Unit (NCCU) at Addenbrooke's Hospital (Cambridge, UK) between October 2014 and December 2017. Read More

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January 2021

Impacts of a Pressure Challenge on Cerebral Critical Closing Pressure and Effective Cerebral Perfusion Pressure in Patients with Traumatic Brain Injury.

Acta Neurochir Suppl 2021 ;131:11-16

Intensive Care Unit, Hospital de Clinicas, Universidad de la Republica, Montevideo, Uruguay.

Introduction: Cerebral critical closing pressure (CrCP) comprises intracranial pressure (ICP) and arteriolar wall tension (WT). It is the arterial blood pressure (ABP) at which small vessels close and circulation stops. We hypothesized that the increase in WT secondary to a systemic hypertensive challenge would lead to an increase in CrCP and that the "effective" cerebral perfusion pressure (CPPeff; calculated as ABP - CrCP) would give more complete information than the "conventional" cerebral perfusion pressure (CPP; calculated as ABP - ICP). Read More

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January 2021

Visualization of Intracranial Pressure Insults After Severe Traumatic Brain Injury: Influence of Individualized Limits of Reactivity.

Acta Neurochir Suppl 2021 ;131:7-10

Academic Neurosurgery, University of Cambridge, Cambridge, UK.

Cerebral perfusion pressure (CPP) lower limits of reactivity can be determined almost continuously after severe traumatic brain injury (TBI), and deviation below the lower limit carries important prognostic information. In this study, we used a recently derived coloured contour method for visualizing intracranial pressure (ICP) insults to describe the influence of having a CPP above the CPP lower limits of reactivity after severe TBI. In a cohort of 729 patients, we examined the relationship between ICP insults and the 6-month Glasgow Outcome Scale score, using colour-coded plots, as described previously. Read More

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January 2021

Microcirculatory Biomarkers of Secondary Cerebral Ischemia in Traumatic Brain Injury.

Acta Neurochir Suppl 2021 ;131:3-5

Lovelace Biomedical Research Institute, Albuquerque, NM, USA.

Aim: The purpose of this study was to study changes in cerebral microcirculation parameters in the development of secondary cerebral ischemia (SCI).

Methods: A total of 202 patients with a Glasgow Coma Scale score ≤ 12 after experiencing a traumatic brain injury (TBI) were recruited for the study within 6 h of the injury. All patients were subjected to perfusion computed tomography. Read More

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January 2021

Neural dysfunctions following experimental permanent occlusions of bilateral common carotid arteries cause an increase of rat voluntary alcohol drinking behavior.

Leg Med (Tokyo) 2021 Apr 2;51:101875. Epub 2021 Apr 2.

Department of Forensic Medicine, Graduate School of Biomedical and Health Sciences, Hiroshima University, Minami-ku, 734-8553 Hiroshima, Japan.

We have previously reported that ischemic animal models treated with a respiratory inhibitor, rotenon, show an increased voluntary alcohol intake. Although it is clear that ischemic brain, as a result of reduced-blood flow, shows pathological events and/or neuro-degenerations apparently, little is known of causal relationship between the mechanism of neural dysfunction and voluntary alcohol consumption. Authors have investigated effects of permanent two-vessel occlusion (p2VO) on rat voluntary alcohol drinking behavior. Read More

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Teleradiology-based stroke network in Western and Southern Transdanubia in Hungary

Orv Hetil 2021 04 10;162(17):668-675. Epub 2021 Apr 10.

6 Pécsi Tudományegyetem, Általános Orvostudományi Kar, Klinikai Központ, Neurológiai Klinika, Pécs.

Összefoglaló. Bevezetés: A stroke kezelésének lehetőségei az utóbbi években jelentősen megváltoztak: a thrombolysis után bevezetésre került a mechanikus thrombectomia, és a terápiás időablak is jelentősen kitágult az utóbbi évek nagy multicentrikus tanulmányai alapján. Ezek a lehetőségek új igényeket fogalmaztak meg a képalkotó diagnosztikával szemben: az ischaemia okozta morfológiai elváltozások mellett az artériás és a kollaterális rendszer állapotát, valamint bizonyos esetekben az agy szöveti perfúzióját is szükséges meghatározni. Read More

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Plasma levels of extracellular vesicles and the risk of post-operative pulmonary embolism in patients with primary brain tumors: a prospective study.

J Thromb Thrombolysis 2021 Apr 10. Epub 2021 Apr 10.

A. Bianchi Bonomi Hemophilia and Thrombosis Center, Fondazione IRCCS Ca' Granda - Ospedale Maggiore Policlinico, Via Pace 9, 20122, Milan, Italy.

Primary brain tumors are associated with an increased risk of pulmonary embolism (PE), particularly in the early post-operative period. The pathophysiological mechanisms of PE are poorly understood. This study aims to describe prospectively extracellular vesicles (EVs) levels and investigate whether or not their variations allow to identify patients at increased risk of post-operative PE. Read More

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Individualized blood pressure targets in the postoperative care of patients with intracerebral hemorrhage.

J Neurosurg 2021 Apr 9:1-10. Epub 2021 Apr 9.

1Neurological Intensive Care Unit, Department of Neurology, and.

Objective: Recent guidelines recommend targeting a systolic blood pressure (SBP) < 140 mm Hg in the early management of patients with spontaneous intracerebral hemorrhage (ICH). The optimal SBP targets for ICH patients after hematoma evacuation (HE) remain unclear. Here, the authors aimed to define the optimal SBP range based on multimodal neuromonitoring data. Read More

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The role of ex-situ hypothermic oxygenated machine perfusion and cold preservation time in extended criteria DCD and DBD.

Liver Transpl 2021 Apr 9. Epub 2021 Apr 9.

General and Liver Transplant Surgery Unit - Fondazione IRCCS Ca' Granda - Ospedale Maggiore Policlinico, Milan.

Hypothermic-oxygenated machine perfusion (HOPE) has the potential to counterbalance the detrimental consequences of cold and warm ischemia time in both brain death donors (DBD) and donors after circulatory death (DCD). Herein, we investigated the protective effects of HOPE in extended criteria (ECD) DBD and over-extended warm ischemia time (WIT) DCD grafts. The present retrospective case-series study included 50 livers subjected to end-ischemic HOPE or dual (D)HOPE in two liver transplant (LT) Centers from January 2018 to December 2019. Read More

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APOE moderates the effect of hippocampal blood flow on memory pattern separation in clinically normal older adults.

Hippocampus 2021 Apr 9. Epub 2021 Apr 9.

Department of Neurology, Memory and Aging Center, University of California, San Francisco (UCSF), San Francisco, California, USA.

Pattern separation, the ability to differentiate new information from previously experienced similar information, is highly sensitive to hippocampal structure and function and declines with age. Functional MRI studies have demonstrated hippocampal hyperactivation in older adults compared to young, with greater task-related activation associated with worse pattern separation performance. The current study was designed to determine whether pattern separation was sensitive to differences in task-free hippocampal cerebral blood flow (CBF) in 130 functionally intact older adults. Read More

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