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Wehrli FW. Recent Advances in MR Imaging-based Quantification of Brain Oxygen Metabolism. Magn Reson Med Sci 2024; 23:377-403. [PMID: 38866481 PMCID: PMC11234951 DOI: 10.2463/mrms.rev.2024-0028] [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: 06/14/2024] Open
Abstract
The metabolic rate of oxygen (MRO2) is fundamental to tissue metabolism. Determination of MRO2 demands knowledge of the arterio-venous difference in hemoglobin-bound oxygen concentration, typically expressed as oxygen extraction fraction (OEF), and blood flow rate (BFR). MRI is uniquely suited for measurement of both these quantities, yielding MRO2 in absolute physiologic units of µmol O2 min-1/100 g tissue. Two approaches are discussed, both relying on hemoglobin magnetism. Emphasis will be on cerebral oxygen metabolism expressed in terms of the cerebral MRO2 (CMRO2), but translation of the relevant technologies to other organs, including kidney and placenta will be touched upon as well. The first class of methods exploits the blood's bulk magnetic susceptibility, which can be derived from field maps. The second is based on measurement of blood water T2, which is modulated by diffusion and exchange in the local-induced fields within and surrounding erythrocytes. Some whole-organ methods achieve temporal resolution adequate to permit time-series studies of brain energetics, for instance, during sleep in the scanner with concurrent electroencephalogram (EEG) sleep stage monitoring. Conversely, trading temporal for spatial resolution has led to techniques for spatially resolved approaches based on quantitative blood oxygen level dependent (BOLD) or calibrated BOLD models, allowing regional assessment of vascular-metabolic parameters, both also exploiting deoxyhemoglobin paramagnetism like their whole-organ counterparts.
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Affiliation(s)
- Felix W Wehrli
- Laboratory for Structural, Physiologic and Functional Imaging (LSPFI), Department of Radiology, Perelman School of Medicine, University Pennsylvania, Philadelphia, Pennsylvania, USA
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2
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Tao X, Zhu Z, Wang L, Li C, Sun L, Wang W, Gong W. Biomarkers of Aging and Relevant Evaluation Techniques: A Comprehensive Review. Aging Dis 2024; 15:977-1005. [PMID: 37611906 PMCID: PMC11081160 DOI: 10.14336/ad.2023.00808-1] [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: 06/03/2023] [Accepted: 08/08/2023] [Indexed: 08/25/2023] Open
Abstract
The risk of developing chronic illnesses and disabilities is increasing with age. To predict and prevent aging, biomarkers relevant to the aging process must be identified. This paper reviews the known molecular, cellular, and physiological biomarkers of aging. Moreover, we discuss the currently available technologies for identifying these biomarkers, and their applications and potential in aging research. We hope that this review will stimulate further research and innovation in this emerging and fast-growing field.
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Affiliation(s)
- Xue Tao
- Department of Research, Beijing Rehabilitation Hospital, Capital Medical University, Beijing, China.
| | - Ziman Zhu
- Beijing Rehabilitation Medicine Academy, Capital Medical University, Beijing, China.
| | - Liguo Wang
- Key Laboratory of Protein Sciences, School of Pharmaceutical Sciences, Tsinghua University, Beijing, China.
| | - Chunlin Li
- School of Biomedical Engineering, Capital Medical University, Beijing, China.
- Beijing Key Laboratory of Fundamental Research on Biomechanics in Clinical Application, Capital Medical University, Beijing, China.
| | - Liwei Sun
- School of Biomedical Engineering, Capital Medical University, Beijing, China.
- Beijing Key Laboratory of Fundamental Research on Biomechanics in Clinical Application, Capital Medical University, Beijing, China.
| | - Wei Wang
- Department of Rehabilitation Radiology, Beijing Rehabilitation Hospital, Capital Medical University, Beijing, China.
| | - Weijun Gong
- Department of Neurological Rehabilitation, Beijing Rehabilitation Hospital, Capital Medical University, Beijing, China.
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3
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Zhang Y. Editorial for "Effect of Physical Exercise on MRI-Assessed Brain Perfusion in Chemotherapy-Treated Breast Cancer Patients: A Randomized Controlled Trial". J Magn Reson Imaging 2024; 59:1681-1682. [PMID: 37587647 DOI: 10.1002/jmri.28966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 05/27/2023] [Indexed: 08/18/2023] Open
Affiliation(s)
- Yue Zhang
- Department of Electronic and Information Engineering, Department of Mechanical and Electrical Engineering, Department of Basic Discipline, Beihai Vocational college, Beihai, China
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Johnson BJ, Lipford ME, Barcus RA, Olson JD, Schaaf GW, Andrews RN, Kim J, Dugan GO, Deycmar S, Reed CA, Whitlow CT, Cline JM. Assessing cerebrovascular reactivity (CVR) in rhesus macaques (Macaca mulatta) using a hypercapnic challenge and pseudo-continuous arterial spin labeling (pCASL). Neuroimage 2024; 285:120491. [PMID: 38070839 PMCID: PMC10842457 DOI: 10.1016/j.neuroimage.2023.120491] [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: 06/27/2023] [Revised: 12/01/2023] [Accepted: 12/06/2023] [Indexed: 01/13/2024] Open
Abstract
Cerebrovascular reactivity (CVR) is a measure of cerebral small vessels' ability to respond to changes in metabolic demand and can be quantified using magnetic resonance imaging (MRI) coupled with a vasoactive stimulus. Reduced CVR occurs with neurodegeneration and is associated with cognitive decline. While commonly measured in humans, few studies have evaluated CVR in animal models. Herein, we describe methods to induce hypercapnia in rhesus macaques (Macaca mulatta) under gas anesthesia to measure cerebral blood flow (CBF) and CVR using pseudo-continuous arterial spin labeling (pCASL). Fifteen (13 M, 2 F) adult rhesus macaques underwent pCASL imaging that included a baseline segment (100% O2) followed by a hypercapnic challenge (isoflurane anesthesia with 5% CO2, 95% O2 mixed gas). Relative hypercapnia was defined as an end-tidal CO2 (ETCO2) ≥5 mmHg above baseline ETCO2. The mean ETCO2 during the baseline segment of the pCASL sequence was 34 mmHg (range: 23-48 mmHg). During this segment, mean whole-brain CBF was 51.48 ml/100g/min (range: 21.47-77.23 ml/100g/min). Significant increases (p<0.0001) in ETCO2 were seen upon inspiration of the mixed gas (5% CO2, 95% O2). The mean increase in ETCO2 was 8.5 mmHg and corresponded with a mean increase in CBF of 37.1% (p<0.0001). The mean CVR measured was 4.3%/mmHg. No anesthetic complications occurred as a result of the CO2 challenge. Our methods were effective at inducing a state of relative hypercapnia that corresponds with a detectable increase in whole brain CBF using pCASL MRI. Using these methods, a CO2 challenge can be performed in conjunction with pCASL imaging to evaluate CBF and CVR in rhesus macaques. The measured CVR in rhesus macaques is comparable to human CVR highlighting the translational utility of rhesus macaques in neuroscience research. These methods present a feasible means to measure CVR in comparative models of neurodegeneration and cerebrovascular dysfunction.
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Affiliation(s)
- Brendan J Johnson
- Department of Pathology, Section on Comparative Medicine, Wake Forest University School of Medicine, 1 Medical Center Blvd, Winston-Salem, NC, United States.
| | - Megan E Lipford
- Department of Radiology, Wake Forest University School of Medicine, 1 Medical Center Blvd, Winston-Salem, NC, United States; Department of Biomedical Engineering, Wake Forest University School of Medicine, 1 Medical Center Blvd, Winston-Salem, NC, United States
| | - Richard A Barcus
- Department of Radiology, Wake Forest University School of Medicine, 1 Medical Center Blvd, Winston-Salem, NC, United States
| | - John D Olson
- Department of Pathology, Section on Comparative Medicine, Wake Forest University School of Medicine, 1 Medical Center Blvd, Winston-Salem, NC, United States
| | - George W Schaaf
- Department of Pathology, Section on Comparative Medicine, Wake Forest University School of Medicine, 1 Medical Center Blvd, Winston-Salem, NC, United States
| | - Rachel N Andrews
- Department of Radiation Oncology, Section on Radiation Biology, Wake Forest University School of Medicine, 1 Medical Center Blvd, Winston-Salem, NC, United States
| | - Jeongchul Kim
- Department of Radiology, Wake Forest University School of Medicine, 1 Medical Center Blvd, Winston-Salem, NC, United States
| | - Greg O Dugan
- Department of Pathology, Section on Comparative Medicine, Wake Forest University School of Medicine, 1 Medical Center Blvd, Winston-Salem, NC, United States
| | - Simon Deycmar
- Department of Pathology, Section on Comparative Medicine, Wake Forest University School of Medicine, 1 Medical Center Blvd, Winston-Salem, NC, United States
| | - Colin A Reed
- Department of Pathology, Section on Comparative Medicine, Wake Forest University School of Medicine, 1 Medical Center Blvd, Winston-Salem, NC, United States
| | - Christopher T Whitlow
- Wake Forest Baptist Comprehensive Cancer Center, Wake Forest University School of Medicine, 1 Medical Center Blvd, Winston-Salem, NC, United States; Department of Radiology, Wake Forest University School of Medicine, 1 Medical Center Blvd, Winston-Salem, NC, United States; Department of Biomedical Engineering, Wake Forest University School of Medicine, 1 Medical Center Blvd, Winston-Salem, NC, United States; Department of Biostatistics and Data Science, Wake Forest University School of Medicine, 1 Medical Center Blvd, Winston-Salem, NC, United States
| | - J Mark Cline
- Department of Pathology, Section on Comparative Medicine, Wake Forest University School of Medicine, 1 Medical Center Blvd, Winston-Salem, NC, United States; Wake Forest Baptist Comprehensive Cancer Center, Wake Forest University School of Medicine, 1 Medical Center Blvd, Winston-Salem, NC, United States; Department of Radiation Oncology, Section on Radiation Biology, Wake Forest University School of Medicine, 1 Medical Center Blvd, Winston-Salem, NC, United States
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Baas KPA, Vu C, Shen J, Coolen BF, Biemond BJ, Strijkers GJ, Wood JC, Nederveen AJ. Venous Blood Oxygenation Measurements Using TRUST and T2-TRIR MRI During Hypoxic and Hypercapnic Gas Challenges. J Magn Reson Imaging 2023; 58:1903-1914. [PMID: 37092724 DOI: 10.1002/jmri.28744] [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: 02/21/2023] [Revised: 03/31/2023] [Accepted: 03/31/2023] [Indexed: 04/25/2023] Open
Abstract
BACKGROUND Oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen (CMRO2 ) may serve as biomarkers in several diseases. OEF and CMRO2 can be estimated from venous blood oxygenation (Yv ) levels, which in turn can be calculated from venous blood T2 values (T2b ). T2b can be measured using different MRI sequences, including T2-relaxation-under-spin-tagging (TRUST) and T2-prepared-blood-relaxation-imaging-with-inversion-recovery (T2-TRIR). The latter measures both T2b and T1 (T1b ) but was found previously to overestimate T2b compared to TRUST. It remained unclear, however, if this bias is constant across higher and lower oxygen saturations. PURPOSE To compare TRUST and T2-TRIR across a range of O2 saturations using hypoxic and hypercapnic gas challenges. STUDY TYPE Prospective. POPULATION Twelve healthy volunteers (four female, age 36 ± 10 years). FIELD STRENGTH/SEQUENCE A 3T; turbo-field echo-planar-imaging (TFEPI), echo-planar-imaging (EPI), and fast-field-echo (FFE). ASSESSMENT TRUST- and T2-TRIR-derived T2b , Yv , OEF, and CMRO2 were compared across different respiratory challenges. T1b from T2-TRIR was used to estimate Hct (HctTRIR ) and compared with venipuncture (HctVP ). STATISTICAL TESTS Shapiro-Wilk, one-sample and paired-sample t-test, repeated measures ANOVA, Friedman test, Bland-Altman, and correlation analysis. Bonferroni multiple-comparison correction was performed. Significance level was 0.05. RESULTS A significant bias was observed between TRUST- and T2-TRIR-derived T2b , Yv , and OEF values (-13 ± 11 msec, -5.3% ± 3.5% and 5.9 ± 4.1%, respectively). For Yv and OEF, this bias was constant across the range of measured values. T1b was significantly lower during severe hypoxia and hypercapnia compared to baseline (1712 ± 86 msec and 1634 ± 79 msec compared to 1757 ± 90 msec). While no significant bias was found between HctVP and HctTRIR (0.02% ± 0.06%, P = 0.20), the correlation between these Hct values was significant but weak (r = 0.19). DATA CONCLUSION Given the constant bias, TRUST- and T2-TRIR-derived venous T2b values can be used interchangeably to estimate Yv , OEF, and CMRO2 across a broad range of oxygen saturations. Hct from T2-TRIR-derived T1-values only weakly correlated with Hct from venipuncture. EVIDENCE LEVEL 2 TECHNICAL EFFICACY: Stage 2.
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Affiliation(s)
- Koen P A Baas
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Chau Vu
- Biomedical Engineering, University of Southern California, Los Angeles, California, USA
| | - Jian Shen
- Biomedical Engineering, University of Southern California, Los Angeles, California, USA
| | - Bram F Coolen
- Department of Biomedical Engineering and Physics, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands
| | - Bart J Biemond
- Department of Hematology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Gustav J Strijkers
- Department of Biomedical Engineering and Physics, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands
| | - John C Wood
- Biomedical Engineering, University of Southern California, Los Angeles, California, USA
- Division of Cardiology, Children's Hospital Los Angeles, University of Southern California, Los Angeles, California, USA
| | - Aart J Nederveen
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
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Gubler FS, Turan EI, Ramlagan S, Ackermans L, Kubben PL, Kuijf ML, Temel Y. Brain vascularization in deep brain stimulation surgeries: epilepsy, Parkinson's disease, and obsessive-compulsive disorder. J Neurosurg Sci 2023; 67:567-575. [PMID: 35380200 DOI: 10.23736/s0390-5616.22.05606-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND In our experience, we encountered more blood vessels during deep brain stimulation (DBS) surgeries in epilepsy. In this study, we have quantified and compared the cerebral vascularization in epilepsy, Parkinson's disease (PD) and obsessive-compulsive disorder (OCD). METHODS A retrospective observational study in 15 epilepsy and 15 PD patients was performed. The amount, location, and size of blood vessels within 5 millimeters (mm) of all DBS electrode trajectories (N.=120) for both targets (anterior nucleus of the thalamus: ANT and subthalamic nucleus: STN) in both patient groups were quantified and compared on a Medtronic workstation (Dublin, Ireland). Additionally, blood vessels in the trajectories (N.=120) of another group of 15 PD (STN) and 15 OCD (ventral capsule-ventral striatum [VC-VS]) patients were quantified and compared (trajectories N.=120), also to the first group. Statistical analyses were performed with SPSS version 27.0 (descriptive statistics, independent samples t-tests, Mann Whitney U Test, ANOVA Test and post-hoc Tukey Test). A P value <0.05 was considered statistically significant. RESULTS Our results showed a significant greater amount of cerebral blood vessels in epilepsy patients (10 SD±4) compared to PD (PD1 6 SD±1 and PD2 5 SD±3) and OCD (5 SD±1) with P<0.0001. Also, all other subanalyses showed more vascularization in the epilepsy group. CONCLUSIONS Our results show that the brain of epilepsy patients seems to be more vascularized compared to PD and OCD patients. This can make the surgical planning for DBS more challenging, and the use of multiple trajectories limited.
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Affiliation(s)
- Felix S Gubler
- Department of Neurosurgery, Maastricht University Medical Center, Maastricht, the Netherlands -
| | - Engin I Turan
- Department of Neurosurgery, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Shalini Ramlagan
- Department of Neurosurgery, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Linda Ackermans
- Department of Neurosurgery, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Pieter L Kubben
- Department of Neurosurgery, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Mark L Kuijf
- Department of Neurology, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Yasin Temel
- Department of Neurosurgery, Maastricht University Medical Center, Maastricht, the Netherlands
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Eldirdiri A, Zhuo J, Lin Z, Lu H, Gullapalli RP, Jiang D. Toward vendor-independent measurement of cerebral venous oxygenation: Comparison of TRUST MRI across three major MRI manufacturers and association with end-tidal CO 2. NMR IN BIOMEDICINE 2023; 36:e4990. [PMID: 37315951 PMCID: PMC10801912 DOI: 10.1002/nbm.4990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 05/29/2023] [Accepted: 05/30/2023] [Indexed: 06/16/2023]
Abstract
Cerebral venous oxygenation (Yv ) is a valuable biomarker for a variety of brain diseases. T2 relaxation under spin tagging (TRUST) MRI is a widely used method for Yv quantification. In this work, there were two main objectives. The first was to evaluate the reproducibility of TRUST Yv measurements across MRI scanners from different vendors. The second was to examine the correlation between Yv and end-tidal CO2 (EtCO2 ) in a multisite, multivendor setting and determine the usefulness of this correlation to account for variations in Yv caused by normal variations and physiological fluctuations. Standardized TRUST pulse sequences were implemented on three scanners from major MRI vendors (GE, Siemens, Philips). These scanners were located at two research institutions. Ten healthy subjects were scanned. On each scanner, the subject underwent two scan sessions, each of which included three TRUST scans, to evaluate the intrasession and intersession reproducibility of Yv . Each scanner was also equipped with a capnograph device to record the EtCO2 of the subject during the MRI scan. We found no significant bias in Yv measurements across the three scanners (P = 0.18). The measured Yv values on the three scanners were also strongly correlated with each other (intraclass correlation coefficients > 0.85, P < 0.001). The intrasession and intersession coefficients of variation of Yv were less than 4% and showed no significant difference among the scanners. In addition, our results revealed that (1) within the same subject, Yv increased with EtCO2 at a rate of 1.24 ± 0.17%/mmHg (P < 0.0001), and (2) across different subjects, individuals with a higher EtCO2 had a higher Yv , at a rate of 0.94 ± 0.36%/mmHg (P = 0.01). These results suggest that (1) the standardized TRUST sequences had similar accuracies and reproducibilities for the quantification of Yv across the scanners, and (2) recording of EtCO2 may be a useful complement to Yv measurement to account for CO2 -related physiological fluctuations in Yv in multisite, multivendor studies.
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Affiliation(s)
- Abubakr Eldirdiri
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Jiachen Zhuo
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Zixuan Lin
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Hanzhang Lu
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, Maryland, USA
| | - Rao P. Gullapalli
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Dengrong Jiang
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Fesharaki NJ, Taylor A, Mosby K, Kim JH, Ress D. Global effects of aging on the hemodynamic response function in the human brain. RESEARCH SQUARE 2023:rs.3.rs-3299293. [PMID: 37720046 PMCID: PMC10503846 DOI: 10.21203/rs.3.rs-3299293/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/19/2023]
Abstract
In functional magnetic resonance imaging, the hemodynamic response function (HRF) is a transient, stereotypical response to local changes in cerebral hemodynamics and oxygen metabolism due to briefly (< 4 s) evoked neural activity. Accordingly, the HRF is often used as an impulse response with the assumption of linearity in data analysis. In cognitive aging studies, it has been very common to interpret differences in brain activation as age-related changes in neural activity. Contrary to this assumption, however, evidence has accrued that normal aging may also significantly affect the vasculature, thereby affecting cerebral hemodynamics and metabolism, confounding interpretation of fMRI aging studies. In this study, use was made of a multisensory stimulus to evoke the HRF in ~ 87% of cerebral cortex in cognitively intact adults with ages ranging from 22-75 years. The stimulus evokes both positive and negative HRFs, which were characterized using model-free parameters in native-space coordinates. Results showed significant age trends in HRF parameter distributions in terms of both amplitudes (e.g., peak amplitude and CNR) and temporal dynamics (e.g., full-width-at-half-maximum). This work sets the stage for using HRF methods as a biomarker for age-related pathology.
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9
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Biondetti E, Cho J, Lee H. Cerebral oxygen metabolism from MRI susceptibility. Neuroimage 2023; 276:120189. [PMID: 37230206 PMCID: PMC10335841 DOI: 10.1016/j.neuroimage.2023.120189] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 04/26/2023] [Accepted: 05/23/2023] [Indexed: 05/27/2023] Open
Abstract
This article provides an overview of MRI methods exploiting magnetic susceptibility properties of blood to assess cerebral oxygen metabolism, including the tissue oxygen extraction fraction (OEF) and the cerebral metabolic rate of oxygen (CMRO2). The first section is devoted to describing blood magnetic susceptibility and its effect on the MRI signal. Blood circulating in the vasculature can have diamagnetic (oxyhemoglobin) or paramagnetic properties (deoxyhemoglobin). The overall balance between oxygenated and deoxygenated hemoglobin determines the induced magnetic field which, in turn, modulates the transverse relaxation decay of the MRI signal via additional phase accumulation. The following sections of this review then illustrate the principles underpinning susceptibility-based techniques for quantifying OEF and CMRO2. Here, it is detailed whether these techniques provide global (OxFlow) or local (Quantitative Susceptibility Mapping - QSM, calibrated BOLD - cBOLD, quantitative BOLD - qBOLD, QSM+qBOLD) measurements of OEF or CMRO2, and what signal components (magnitude or phase) and tissue pools they consider (intravascular or extravascular). Validations studies and potential limitations of each method are also described. The latter include (but are not limited to) challenges in the experimental setup, the accuracy of signal modeling, and assumptions on the measured signal. The last section outlines the clinical uses of these techniques in healthy aging and neurodegenerative diseases and contextualizes these reports relative to results from gold-standard PET.
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Affiliation(s)
- Emma Biondetti
- Department of Neuroscience, Imaging and Clinical Sciences, "D'Annunzio University" of Chieti-Pescara, Chieti, Italy; Institute for Advanced Biomedical Technologies, "D'Annunzio University" of Chieti-Pescara, Chieti, Italy
| | - Junghun Cho
- Department of Biomedical Engineering, University at Buffalo, The State University of New York, New York, USA
| | - Hyunyeol Lee
- School of Electronic and Electrical Engineering, Kyungpook National University, Daegu, Republic of Korea; Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
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10
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Hou X, Guo P, Wang P, Liu P, Lin DDM, Fan H, Li Y, Wei Z, Lin Z, Jiang D, Jin J, Kelly C, Pillai JJ, Huang J, Pinho MC, Thomas BP, Welch BG, Park DC, Patel VM, Hillis AE, Lu H. Deep-learning-enabled brain hemodynamic mapping using resting-state fMRI. NPJ Digit Med 2023; 6:116. [PMID: 37344684 PMCID: PMC10284915 DOI: 10.1038/s41746-023-00859-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 06/09/2023] [Indexed: 06/23/2023] Open
Abstract
Cerebrovascular disease is a leading cause of death globally. Prevention and early intervention are known to be the most effective forms of its management. Non-invasive imaging methods hold great promises for early stratification, but at present lack the sensitivity for personalized prognosis. Resting-state functional magnetic resonance imaging (rs-fMRI), a powerful tool previously used for mapping neural activity, is available in most hospitals. Here we show that rs-fMRI can be used to map cerebral hemodynamic function and delineate impairment. By exploiting time variations in breathing pattern during rs-fMRI, deep learning enables reproducible mapping of cerebrovascular reactivity (CVR) and bolus arrival time (BAT) of the human brain using resting-state CO2 fluctuations as a natural "contrast media". The deep-learning network is trained with CVR and BAT maps obtained with a reference method of CO2-inhalation MRI, which includes data from young and older healthy subjects and patients with Moyamoya disease and brain tumors. We demonstrate the performance of deep-learning cerebrovascular mapping in the detection of vascular abnormalities, evaluation of revascularization effects, and vascular alterations in normal aging. In addition, cerebrovascular maps obtained with the proposed method exhibit excellent reproducibility in both healthy volunteers and stroke patients. Deep-learning resting-state vascular imaging has the potential to become a useful tool in clinical cerebrovascular imaging.
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Affiliation(s)
- Xirui Hou
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Pengfei Guo
- Department of Computer Science, Johns Hopkins University, Baltimore, MD, USA
| | - Puyang Wang
- Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Peiying Liu
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Doris D M Lin
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Hongli Fan
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Yang Li
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Zhiliang Wei
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
| | - Zixuan Lin
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Dengrong Jiang
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jin Jin
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Catherine Kelly
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jay J Pillai
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Judy Huang
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Marco C Pinho
- Department of Radiology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Binu P Thomas
- Department of Radiology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Babu G Welch
- Department of Neurologic Surgery, UT Southwestern Medical Center, Dallas, TX, USA
- Center for Vital Longevity, School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, TX, USA
| | - Denise C Park
- Center for Vital Longevity, School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, TX, USA
| | - Vishal M Patel
- Department of Computer Science, Johns Hopkins University, Baltimore, MD, USA
- Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Argye E Hillis
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Hanzhang Lu
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA.
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11
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Lin Z, Lim C, Jiang D, Soldan A, Pettigrew C, Oishi K, Zhu Y, Moghekar A, Liu P, Albert M, Lu H. Longitudinal changes in brain oxygen extraction fraction (OEF) in older adults: Relationship to markers of vascular and Alzheimer's pathology. Alzheimers Dement 2023; 19:569-577. [PMID: 35791732 PMCID: PMC10838398 DOI: 10.1002/alz.12727] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 05/18/2022] [Accepted: 05/31/2022] [Indexed: 11/07/2022]
Abstract
INTRODUCTION Oxygen extraction fraction (OEF) reflects the balance between oxygen delivery and consumption. We longitudinally measured OEF in older adults to examine the relationship with markers of Alzheimer's disease (AD) and vascular pathology. METHODS One hundred thirty-seven participants were studied at two time-points at an interval of 2.16 years. OEF was measured using T2 -relaxation-under-spin-tagging (TRUST) magnetic resonance imaging (MRI). The association between OEF and vascular risks, white matter hyperintensities (WMH), cerebrospinal fluid (CSF) measures of amyloid beta (Aβ), total tau (t-tau), and phosphorylated tau 181 (p-tau181) was examined. RESULTS OEF increased from baseline to follow-up. The increase in OEF was more prominent in individuals with high vascular risks compared to those with low vascular risks, and was associated with progression of vascular risks and the growth in WMH volume. OEF change was not related to CSF markers of AD pathology or their progression. DISCUSSION Longitudinal OEF change in older adults is primarily related to vascular pathology.
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Affiliation(s)
- Zixuan Lin
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Chantelle Lim
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Dengrong Jiang
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Anja Soldan
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Corinne Pettigrew
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Kumiko Oishi
- Center for Imaging Science, Whiting School of Engineering, Johns Hopkins University, Baltimore, Maryland, USA
| | - Yuxin Zhu
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Abhay Moghekar
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Peiying Liu
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Marilyn Albert
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Hanzhang Lu
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- F.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
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12
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Hays Weeks CC, Zlatar ZZ, Meloy MJ, Shin DD, Thomas L, Wierenga CE. APOE Genotype Modifies the Association of Fusiform Gyrus Cerebral Metabolic Rate of Oxygen Consumption and Object Naming Performance. J Alzheimers Dis 2023; 91:1371-1383. [PMID: 36641668 DOI: 10.3233/jad-220749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
BACKGROUND The apolipoprotein E (APOE) ɛ4 allele confers risk for age and Alzheimer's disease related cognitive decline but the mechanistic link remains poorly understood. Blood oxygenation level dependent (BOLD) response in the fusiform gyrus (FG) during object naming appears greater among APOEɛ4 carriers even in the face of equivalent cognitive performance, suggesting neural compensation. However, BOLD is susceptible to known age and APOE-related vascular changes that could confound its interpretation. OBJECTIVE To address this limitation, we used calibrated fMRI during an object naming task and a hypercapnic challenge to obtain a more direct measure of neural function - percent change cerebral metabolic rate of oxygen consumption (%ΔCMRO2). METHODS Participants were 45 older adults without dementia (28 ɛ4-, 17 ɛ4+) between the ages of 65 and 85. We examined APOE-related differences in %ΔCMRO2 in the FG during object naming and the extent to which APOE modified associations between FG %ΔCMRO2 and object naming accuracy. Exploratory analyses also tested the hypothesis that %ΔCMRO2 is less susceptible to vascular compromise than are measures of %ΔCBF and %ΔBOLD. RESULTS We observed a modifying role of APOE on associations between FG %ΔCMRO2 and cognition, with ɛ4 carriers (but not non-carriers) demonstrating a positive association between right FG %ΔCMRO2 and object naming accuracy. CONCLUSION Results suggest that the relationship between neural function and cognition is altered among older adult APOEɛ4 carriers prior to the onset of dementia, implicating CMRO2 response as a potential mechanism to support cognition in APOE-related AD risk.
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Affiliation(s)
- Chelsea C Hays Weeks
- VA San Diego Healthcare System, San Diego, CA, USA.,Department of Psychiatry, UC San Diego, La Jolla, CA, USA
| | | | - M J Meloy
- VA San Diego Healthcare System, San Diego, CA, USA
| | | | - Liu Thomas
- Department of Radiology, UC San Diego, La Jolla, CA, USA
| | - Christina E Wierenga
- VA San Diego Healthcare System, San Diego, CA, USA.,Department of Psychiatry, UC San Diego, La Jolla, CA, USA
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13
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Shams S, Prokopiou P, Esmaelbeigi A, Mitsis GD, Chen JJ. Modeling the dynamics of cerebrovascular reactivity to carbon dioxide in fMRI under task and resting-state conditions. Neuroimage 2023; 265:119758. [PMID: 36442732 DOI: 10.1016/j.neuroimage.2022.119758] [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: 07/06/2022] [Revised: 11/11/2022] [Accepted: 11/18/2022] [Indexed: 11/26/2022] Open
Abstract
Conventionally, cerebrovascular reactivity (CVR) is estimated as the amplitude of the hemodynamic response to vascular stimuli, most commonly carbon dioxide (CO2). While the CVR amplitude has established clinical utility, the temporal characteristics of CVR (dCVR) have been increasingly explored and may yield even more pathology-sensitive parameters. This work is motivated by the current need to evaluate the feasibility of dCVR modeling in various experimental conditions. In this work, we present a comparison of several recently published/utilized model-based deconvolution (response estimation) approaches for estimating the CO2 response function h(t), including maximum a posteriori likelihood (MAP), inverse logit (IL), canonical correlation analysis (CCA), and basis expansion (using Gamma and Laguerre basis sets). To aid the comparison, we devised a novel simulation framework that incorporates a wide range of SNRs, ranging from 10 to -7 dB, representative of both task and resting-state CO2 changes. In addition, we built ground-truth h(t) into our simulation framework, overcoming the conventional limitation that the true h(t) is unknown. Moreover, to best represent realistic noise found in fMRI scans, we extracted noise from in-vivo resting-state scans. Furthermore, we introduce a simple optimization of the CCA method (CCAopt) and compare its performance to these existing methods. Our findings suggest that model-based methods can accurately estimate dCVR even amidst high noise (i.e. resting-state), and in a manner that is largely independent of the underlying model assumptions for each method. We also provide a quantitative basis for making methodological choices, based on the desired dCVR parameters, the estimation accuracy and computation time. The BEL method provided the highest accuracy and robustness, followed by the CCAopt and IL methods. Of the three, the CCAopt method has the lowest computational requirements. These findings lay the foundation for wider adoption of dCVR estimation in CVR mapping.
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Affiliation(s)
- Seyedmohammad Shams
- Rotman Research Institute, Baycrest Health Sciences, Canada; Department of Neurology, Henry Ford Health, USA
| | - Prokopis Prokopiou
- Department of Radiology, Gordon Center for Medical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | | | | | - J Jean Chen
- Rotman Research Institute, Baycrest Health Sciences, Canada; Department of Bioengineering, McGill University, Canada; Department of Medical Biophysics, University of Toronto, Canada; Institute of Biomedical Engineering, University of Toronto, Canada.
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14
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Vascular Aging and Damage in Patients with Iron Metabolism Disorders. Diagnostics (Basel) 2022; 12:diagnostics12112817. [PMID: 36428877 PMCID: PMC9689457 DOI: 10.3390/diagnostics12112817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Revised: 11/06/2022] [Accepted: 11/11/2022] [Indexed: 11/18/2022] Open
Abstract
Vascular aging is a physiological, multifactorial process that involves every type of vessel, from large arteries to microcirculation. This manifests itself as impaired vasomotor function, altered secretory phenotype, deteriorated intercellular transport function, structural remodeling, and aggravated barrier function between the blood and the vascular smooth muscle layer. Iron disorders, particularly iron overload, may lead to oxidative stress and, among other effects, vascular aging. The elevated transferrin saturation and serum iron levels observed in iron overload lead to the formation of a non-transferrin-bound iron (NTBI) fraction with high pro-oxidant activity. NTBI can induce the production of reactive oxygen species (ROS), which induce lipid peroxidation and mediate iron-related damage as the elements of oxidative stress in many tissues, including heart and vessels' mitochondria. However, the available data make it difficult to precisely determine the impact of iron metabolism disorders on vascular aging; therefore, the relationship requires further investigation. Our study aims to present the current state of knowledge on vascular aging in patients with deteriorated iron metabolism.
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15
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Bhatia K, Kindelin A, Nadeem M, Khan MB, Yin J, Fuentes A, Miller K, Turner GH, Preul MC, Ahmad AS, Mufson EJ, Waters MF, Ahmad S, Ducruet AF. Complement C3a Receptor (C3aR) Mediates Vascular Dysfunction, Hippocampal Pathology, and Cognitive Impairment in a Mouse Model of VCID. Transl Stroke Res 2022; 13:816-829. [PMID: 35258803 DOI: 10.1007/s12975-022-00993-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 01/24/2022] [Accepted: 01/28/2022] [Indexed: 01/12/2023]
Abstract
Vascular contributions to cognitive impairment and dementia (VCID) secondary to chronic mild-moderate cerebral ischemia underlie a significant percentage of cases of dementia. We previously reported that either genetic deficiency of the complement C3a receptor (C3aR) or its pharmacological inhibition protects against cerebral ischemia in rodents, while others have implicated C3aR in the pathogenesis seen in rodent transgenic models of Alzheimer's disease. In the present study, we evaluated the role of complement C3a-C3aR signaling in the onset and progression of VCID. We utilized the bilateral common carotid artery stenosis (BCAS) model to induce VCID in male C57BL/6 wild-type and C3aR-knockout (C3aR-/-) mice. Cerebral blood flow (CBF) changes, hippocampal atrophy (HA), white matter degeneration (WMD), and ventricular size were assessed at 4 months post-BCAS using laser speckle contrast analysis (LSCI) and magnetic resonance imaging (MRI). Cognitive function was evaluated using the Morris water maze (MWM), and novel object recognition (NOR), immunostaining, and western blot were performed to assess the effect of genetic C3aR deletion on post-VCID outcomes. BCAS resulted in decreased CBF and increased HA, WMD, and neurovascular inflammation in WT (C57BL/6) compared to C3aR-/- (C3aR-KO) mice. Moreover, C3aR-/- mice exhibited improved cognitive function on NOR and MWM relative to WT controls. We conclude that over-activation of the C3a/C3aR axis exacerbates neurovascular inflammation leading to poor VCID outcomes which are mitigated by C3aR deletion. Future studies are warranted to dissect the role of cell-specific C3aR in VCID.
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Affiliation(s)
- Kanchan Bhatia
- Department of Neurosurgery, Barrow Neurological Institute, SJHMC, Dignity Health, Phoenix, AZ, 85013, USA
- School of Mathematical and Natural Sciences, Arizona State University, Phoenix, AZ, USA
| | - Adam Kindelin
- Department of Neurosurgery, Barrow Neurological Institute, SJHMC, Dignity Health, Phoenix, AZ, 85013, USA
| | - Muhammad Nadeem
- Department of Translational Neuroscience, Barrow Neurological Institute, SJHMC, Dignity Health, Phoenix, AZ, 85013, USA
| | | | - Junxiang Yin
- Department of Translational Neuroscience, Barrow Neurological Institute, SJHMC, Dignity Health, Phoenix, AZ, 85013, USA
- Department of Neurology, Barrow Neurological Institute, SJHMC, Dignity Health, Phoenix, AZ, 85013, USA
| | - Alberto Fuentes
- Barrow Neurological Institute/Arizona State University Center for Preclinical Imaging, Barrow Neurological Institute, SJHMC, Dignity Health, Phoenix, AZ, 85013, USA
| | - Karis Miller
- Department of Neurosurgery, Barrow Neurological Institute, SJHMC, Dignity Health, Phoenix, AZ, 85013, USA
- Department of Translational Neuroscience, Barrow Neurological Institute, SJHMC, Dignity Health, Phoenix, AZ, 85013, USA
| | - Gregory H Turner
- Barrow Neurological Institute/Arizona State University Center for Preclinical Imaging, Barrow Neurological Institute, SJHMC, Dignity Health, Phoenix, AZ, 85013, USA
| | - Mark C Preul
- Department of Neurosurgery, Barrow Neurological Institute, SJHMC, Dignity Health, Phoenix, AZ, 85013, USA
| | - Abdullah S Ahmad
- Department of Translational Neuroscience, Barrow Neurological Institute, SJHMC, Dignity Health, Phoenix, AZ, 85013, USA
- Department of Neurology, Barrow Neurological Institute, SJHMC, Dignity Health, Phoenix, AZ, 85013, USA
| | - Elliott J Mufson
- Department of Translational Neuroscience, Barrow Neurological Institute, SJHMC, Dignity Health, Phoenix, AZ, 85013, USA
| | - Michael F Waters
- Department of Translational Neuroscience, Barrow Neurological Institute, SJHMC, Dignity Health, Phoenix, AZ, 85013, USA
- Department of Neurology, Barrow Neurological Institute, SJHMC, Dignity Health, Phoenix, AZ, 85013, USA
| | - Saif Ahmad
- Department of Neurosurgery, Barrow Neurological Institute, SJHMC, Dignity Health, Phoenix, AZ, 85013, USA.
- Department of Translational Neuroscience, Barrow Neurological Institute, SJHMC, Dignity Health, Phoenix, AZ, 85013, USA.
| | - Andrew F Ducruet
- Departments of Neurosurgery & Translational Neuroscience, Barrow Neurological Institute, SJHMC, Dignity Health, Phoenix, AZ, 85086, USA.
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16
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Liu P, Baker Z, Li Y, Li Y, Xu J, Park DC, Welch BG, Pinho M, Pillai JJ, Hillis AE, Mori S, Lu H. CVR-MRICloud: An online processing tool for CO2-inhalation and resting-state cerebrovascular reactivity (CVR) MRI data. PLoS One 2022; 17:e0274220. [PMID: 36170233 PMCID: PMC9518872 DOI: 10.1371/journal.pone.0274220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 08/23/2022] [Indexed: 12/02/2022] Open
Abstract
Cerebrovascular Reactivity (CVR) provides an assessment of the brain's vascular reserve and has been postulated to be a sensitive marker in cerebrovascular diseases. MRI-based CVR measurement typically employs alterations in arterial carbon dioxide (CO2) level while continuously acquiring Blood-Oxygenation-Level-Dependent (BOLD) images. CO2-inhalation and resting-state methods are two commonly used approaches for CVR MRI. However, processing of CVR MRI data often requires special expertise and may become an obstacle in broad utilization of this promising technique. The aim of this work was to develop CVR-MRICloud, a cloud-based CVR processing pipeline, to enable automated processing of CVR MRI data. The CVR-MRICloud consists of several major steps including extraction of end-tidal CO2 (EtCO2) curve from raw CO2 recording, alignment of EtCO2 curve with BOLD time course, computation of CVR value on a whole-brain, regional, and voxel-wise basis. The pipeline also includes standard BOLD image processing steps such as motion correction, registration between functional and anatomic images, and transformation of the CVR images to canonical space. This paper describes these algorithms and demonstrates the performance of the CVR-MRICloud in lifespan healthy subjects and patients with clinical conditions such as stroke, brain tumor, and Moyamoya disease. CVR-MRICloud has potential to be used as a data processing tool for a variety of basic science and clinical applications.
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Affiliation(s)
- Peiying Liu
- Department of Diagnostic Radiology & Nuclear Medicine, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Zachary Baker
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Yue Li
- AnatomyWorks, LLC, Baltimore, Maryland, United States of America
| | - Yang Li
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Jiadi Xu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- F.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, United States of America
| | - Denise C. Park
- Center for Vital Longevity, School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, Texas, United States of America
| | - Babu G. Welch
- Department of Neurological Surgery, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Marco Pinho
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Jay J. Pillai
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Argye E. Hillis
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Susumu Mori
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- F.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, United States of America
| | - Hanzhang Lu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- F.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, United States of America
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17
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Saillant K, Intzandt B, Bérubé B, Sanami S, Gauthier C, Bherer L. Mastering the Relationship between the Body and the Brain? The Case of a Female Master Athlete. Exp Aging Res 2022; 49:372-388. [PMID: 35950796 DOI: 10.1080/0361073x.2022.2109340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND Physical inactivity significantly increases risk of cardiovascular diseases, which are highly prevalent in aging. Conversely, higher levels of physical activity in aging have been associated with benefits for physical and cognitive health and is hypothesized to prevent and reduce development of cardiovascular risk factors. However, those older adults with the highest activity levels (i.e., Master Athletes [MA]) are relatively understudied, and even fewer studies involve female MA. OBJECTIVE The aim of this study was to compare the physiological, physical, and cognitive profiles of an 83-year-old track-and-field MA runner to a sample of inactive age-matched females. RESULTS Results revealed the MA had a high peak oxygen uptake and had superior performance on visuospatial memory tasks compared to her inactive counterparts. Cerebral blood flow was slightly elevated in the MA, but lower cerebrovascular reactivity was revealed compared to the other female included in the magnetic resonance imaging portion. CONCLUSION Our results suggest that high levels of physical activity have benefits on multiple aspects of an aging female's life and that more studies should include MA, as well as a spectrum of cardiorespiratory fitness to further understand the role of physical activity in female aging.
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Affiliation(s)
- Kathia Saillant
- Department of Psychology, Université du Québec à Montréal, Montréal, Québec, Canada.,Research Center of the Montreal Heart Institute, Montréal, Québec, Canada.,Research Center of the Institut Universitaire de Gériatrie de Montréal, Montréal, Québec, Canada
| | - Brittany Intzandt
- Research Center of the Montreal Heart Institute, Montréal, Québec, Canada.,Research Center of the Institut Universitaire de Gériatrie de Montréal, Montréal, Québec, Canada.,School of Graduate Studies, Concordia University, Montréal, Québec, Canada.,PERFORM Centre, Concordia University, Montréal, Québec, Canada
| | - Béatrice Bérubé
- Department of Psychology, Université du Québec à Montréal, Montréal, Québec, Canada.,Research Center of the Montreal Heart Institute, Montréal, Québec, Canada.,Research Center of the Institut Universitaire de Gériatrie de Montréal, Montréal, Québec, Canada
| | - Safa Sanami
- Research Center of the Montreal Heart Institute, Montréal, Québec, Canada.,PERFORM Centre, Concordia University, Montréal, Québec, Canada.,Physics Department, Concordia University, Montréal, Québec, Canada
| | - Claudine Gauthier
- Research Center of the Montreal Heart Institute, Montréal, Québec, Canada.,PERFORM Centre, Concordia University, Montréal, Québec, Canada.,Physics Department, Concordia University, Montréal, Québec, Canada
| | - Louis Bherer
- Research Center of the Montreal Heart Institute, Montréal, Québec, Canada.,Research Center of the Institut Universitaire de Gériatrie de Montréal, Montréal, Québec, Canada.,Department of Medicine, Université de Montréal, Montréal, Québec, Canada
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18
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Jiang D, Lu H. Cerebral oxygen extraction fraction MRI: Techniques and applications. Magn Reson Med 2022; 88:575-600. [PMID: 35510696 PMCID: PMC9233013 DOI: 10.1002/mrm.29272] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 03/20/2022] [Accepted: 03/29/2022] [Indexed: 12/20/2022]
Abstract
The human brain constitutes 2% of the body's total mass but uses 20% of the oxygen. The rate of the brain's oxygen utilization can be derived from a knowledge of cerebral blood flow and the oxygen extraction fraction (OEF). Therefore, OEF is a key physiological parameter of the brain's function and metabolism. OEF has been suggested to be a useful biomarker in a number of brain diseases. With recent advances in MRI techniques, several MRI-based methods have been developed to measure OEF in the human brain. These MRI OEF techniques are based on the T2 of blood, the blood signal phase, the magnetic susceptibility of blood-containing voxels, the effect of deoxyhemoglobin on signal behavior in extravascular tissue, and the calibration of the BOLD signal using gas inhalation. Compared to 15 O PET, which is considered the "gold standard" for OEF measurement, MRI-based techniques are non-invasive, radiation-free, and are more widely available. This article provides a review of these emerging MRI-based OEF techniques. We first briefly introduce the role of OEF in brain oxygen homeostasis. We then review the methodological aspects of different categories of MRI OEF techniques, including their signal mechanisms, acquisition methods, and data analyses. The strengths and limitations of the techniques are discussed. Finally, we review key applications of these techniques in physiological and pathological conditions.
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Affiliation(s)
- Dengrong Jiang
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Hanzhang Lu
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, Maryland, USA
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19
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Deckers PT, Bhogal AA, Dijsselhof MB, Faraco CC, Liu P, Lu H, Donahue MJ, Siero JC. Hemodynamic and metabolic changes during hypercapnia with normoxia and hyperoxia using pCASL and TRUST MRI in healthy adults. J Cereb Blood Flow Metab 2022; 42:861-875. [PMID: 34851757 PMCID: PMC9014679 DOI: 10.1177/0271678x211064572] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Blood oxygenation level-dependent (BOLD) or arterial spin labeling (ASL) MRI with hypercapnic stimuli allow for measuring cerebrovascular reactivity (CVR). Hypercapnic stimuli are also employed in calibrated BOLD functional MRI for quantifying neuronally-evoked changes in cerebral oxygen metabolism (CMRO2). It is often assumed that hypercapnic stimuli (with or without hyperoxia) are iso-metabolic; increasing arterial CO2 or O2 does not affect CMRO2. We evaluated the null hypothesis that two common hypercapnic stimuli, 'CO2 in air' and carbogen, are iso-metabolic. TRUST and ASL MRI were used to measure the cerebral venous oxygenation and cerebral blood flow (CBF), from which the oxygen extraction fraction (OEF) and CMRO2 were calculated for room-air, 'CO2 in air' and carbogen. As expected, CBF significantly increased (9.9% ± 9.3% and 12.1% ± 8.8% for 'CO2 in air' and carbogen, respectively). CMRO2 decreased for 'CO2 in air' (-13.4% ± 13.0%, p < 0.01) compared to room-air, while the CMRO2 during carbogen did not significantly change. Our findings indicate that 'CO2 in air' is not iso-metabolic, while carbogen appears to elicit a mixed effect; the CMRO2 reduction during hypercapnia is mitigated when including hyperoxia. These findings can be important for interpreting measurements using hypercapnic or hypercapnic-hyperoxic (carbogen) stimuli.
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Affiliation(s)
- Pieter T Deckers
- Department of Neurosurgery, University Medical Center Utrecht, Utrecht, Netherlands
| | - Alex A Bhogal
- Department of Radiology, Center for Image Sciences, University Medical Center Utrecht, Utrecht, Netherlands
| | - Mathijs Bj Dijsselhof
- Department of Radiology, Center for Image Sciences, University Medical Center Utrecht, Utrecht, Netherlands.,Department of Radiology and Nuclear Medicine, Amsterdam Neuroscience, Amsterdam UMC (location VUmc), Amsterdam, Netherlands
| | - Carlos C Faraco
- Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Peiying Liu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Hanzhang Lu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Manus J Donahue
- Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Jeroen Cw Siero
- Department of Radiology, Center for Image Sciences, University Medical Center Utrecht, Utrecht, Netherlands.,Spinoza Centre for Neuroimaging, Amsterdam, Netherlands
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20
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Schneider SC, Archila-Meléndez ME, Göttler J, Kaczmarz S, Zott B, Priller J, Kallmayer M, Zimmer C, Sorg C, Preibisch C. Resting-state BOLD functional connectivity depends on the heterogeneity of capillary transit times in the human brain A combined lesion and simulation study about the influence of blood flow response timing. Neuroimage 2022; 255:119208. [PMID: 35427773 DOI: 10.1016/j.neuroimage.2022.119208] [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: 11/04/2021] [Revised: 02/23/2022] [Accepted: 04/11/2022] [Indexed: 11/25/2022] Open
Abstract
Functional connectivity (FC) derived from blood oxygenation level dependent (BOLD) functional magnetic resonance imaging at rest (rs-fMRI), is commonly interpreted as indicator of neuronal connectivity. In a number of brain disorders, however, metabolic, vascular, and hemodynamic impairments can be expected to alter BOLD-FC independently from neuronal activity. By means of a neurovascular coupling (NVC) model of BOLD-FC, we recently demonstrated that aberrant timing of cerebral blood flow (CBF) responses may influence BOLD-FC. In the current work, we support and extend this finding by empirically linking BOLD-FC with capillary transit time heterogeneity (CTH), which we consider as an indicator of delayed and broadened CBF responses. We assessed 28 asymptomatic patients with unilateral high-grade internal carotid artery stenosis (ICAS) as a hemodynamic lesion model with largely preserved neurocognitive functioning and 27 age-matched healthy controls. For each participant, we obtained rs-fMRI, arterial spin labeling, and dynamic susceptibility contrast MRI to study the dependence of left-right homotopic BOLD-FC on local perfusion parameters. Additionally, we investigated the dependency of BOLD-FC on CBF response timing by detailed simulations. Homotopic BOLD-FC was negatively associated with increasing CTH differences between homotopic brain areas. This relation was more pronounced in asymptomatic ICAS patients even after controlling for baseline CBF and relative cerebral blood volume influences. These findings match simulation results that predict an influence of delayed and broadened CBF responses on BOLD-FC. Results demonstrate that increasing CTH differences between homotopic brain areas lead to BOLD-FC reductions. Simulations suggest that CTH increases correspond to broadened and delayed CBF responses to fluctuations in ongoing neuronal activity.
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Affiliation(s)
- Sebastian C Schneider
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Diagnostic and Interventional Neuroradiology, Ismaningerstr. 22, 81675, Munich, Germany; Technical University of Munich, School of Medicine, Klinikum rechts der Isar, TUM Neuroimaging Center, Ismaningerstr. 22, 81675, Munich, Germany
| | - Mario E Archila-Meléndez
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Diagnostic and Interventional Neuroradiology, Ismaningerstr. 22, 81675, Munich, Germany; Technical University of Munich, School of Medicine, Klinikum rechts der Isar, TUM Neuroimaging Center, Ismaningerstr. 22, 81675, Munich, Germany
| | - Jens Göttler
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Diagnostic and Interventional Neuroradiology, Ismaningerstr. 22, 81675, Munich, Germany; Technical University of Munich, School of Medicine, Klinikum rechts der Isar, TUM Neuroimaging Center, Ismaningerstr. 22, 81675, Munich, Germany
| | - Stephan Kaczmarz
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Diagnostic and Interventional Neuroradiology, Ismaningerstr. 22, 81675, Munich, Germany; Technical University of Munich, School of Medicine, Klinikum rechts der Isar, TUM Neuroimaging Center, Ismaningerstr. 22, 81675, Munich, Germany; Philips GmbH Market DACH, Hamburg, Germany
| | - Benedikt Zott
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Diagnostic and Interventional Neuroradiology, Ismaningerstr. 22, 81675, Munich, Germany; Technical University of Munich, School of Medicine, Klinikum rechts der Isar, TUM Neuroimaging Center, Ismaningerstr. 22, 81675, Munich, Germany
| | - Josef Priller
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Psychiatry, Ismaningerstr. 22, 81675, Munich, Munich, Germany
| | - Michael Kallmayer
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Vascular and Endovascular Surgery, Ismaningerstr. 22, 81675, Munich, Munich, Germany
| | - Claus Zimmer
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Diagnostic and Interventional Neuroradiology, Ismaningerstr. 22, 81675, Munich, Germany
| | - Christian Sorg
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Diagnostic and Interventional Neuroradiology, Ismaningerstr. 22, 81675, Munich, Germany; Technical University of Munich, School of Medicine, Klinikum rechts der Isar, TUM Neuroimaging Center, Ismaningerstr. 22, 81675, Munich, Germany
| | - Christine Preibisch
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Diagnostic and Interventional Neuroradiology, Ismaningerstr. 22, 81675, Munich, Germany; Technical University of Munich, School of Medicine, Klinikum rechts der Isar, TUM Neuroimaging Center, Ismaningerstr. 22, 81675, Munich, Germany; Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Neurology, Ismaningerstr. 22, 81675, Munich, Munich, Germany.
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21
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Champagne AA, Coverdale NS, Allen MD, Tremblay JC, MacPherson REK, Pyke KE, Olver TD, Cook DJ. The physiological basis underlying functional connectivity differences in older adults: A multi-modal analysis of resting-state fMRI. Brain Imaging Behav 2022; 16:1575-1591. [PMID: 35092574 DOI: 10.1007/s11682-021-00570-0] [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: 04/11/2020] [Accepted: 09/27/2021] [Indexed: 11/02/2022]
Abstract
The purpose of this study was to determine if differences in functional connectivity strength (FCS) with age were confounded by vascular parameters including resting cerebral blood flow (CBF0), cerebrovascular reactivity (CVR), and BOLD-CBF coupling. Neuroimaging data were collected from 13 younger adults (24 ± 2 years) and 14 older adults (71 ± 4 years). A dual-echo resting state pseudo-continuous arterial spin labeling sequence was performed, as well as a BOLD breath-hold protocol. A group independent component analysis was used to identify networks, which were amalgamated into a region of interest (ROI). Within the ROI, FC strength (FCS) was computed for all voxels and compared across the groups. CBF0, CVR and BOLD-CBF coupling were examined within voxels where FCS was different between young and older adults. FCS was greater in old compared to young (P = 0.001). When the effect of CBF0, CVR and BOLD-CBF coupling on FCS was examined, BOLD-CBF coupling had a significant effect (P = 0.003) and group differences in FCS were not present once all vascular parameters were considered in the statistical model (P = 0.07). These findings indicate that future studies of FCS should consider vascular physiological markers in order to improve our understanding of aging processes on brain connectivity.
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Affiliation(s)
- Allen A Champagne
- Centre for Neuroscience Studies, Queen's University, Room 260, Kingston, ON, K7L 3N6, Canada
| | - Nicole S Coverdale
- Centre for Neuroscience Studies, Queen's University, Room 260, Kingston, ON, K7L 3N6, Canada
| | - Matti D Allen
- Department of Physical Medicine and Rehabilitation, Queen's University, Kingston, ON, Canada.,School of Kinesiology and Health Studies, Cardiovascular Stress Response Laboratory, Queen's University, Kingston, ON, K7L 3N6, Canada.,Department of Physical Medicine and Rehabilitation, Providence Care Hospital, 752 King St., Ontario, West Kingston, Canada
| | - Joshua C Tremblay
- School of Kinesiology and Health Studies, Cardiovascular Stress Response Laboratory, Queen's University, Kingston, ON, K7L 3N6, Canada
| | - Rebecca E K MacPherson
- Department of Health Sciences, Faculty of Applied Health Sciences, Brock University, 1812 Sir Isaac Brock Way, St Catharines, ON, L2S 3A1, Canada
| | - Kyra E Pyke
- School of Kinesiology and Health Studies, Cardiovascular Stress Response Laboratory, Queen's University, Kingston, ON, K7L 3N6, Canada
| | - T Dylan Olver
- Biomedical Sciences, Western College of Veterinarian Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan, S7N 5B4, Canada
| | - Douglas J Cook
- Centre for Neuroscience Studies, Queen's University, Room 260, Kingston, ON, K7L 3N6, Canada. .,Department of Surgery, Queen's University, Room 232, 18 Stuart St, Kingston, ON, K7L 3N6, Canada.
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22
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Liu P, Jiang D, Albert M, Bauer CE, Caprihan A, Gold BT, Greenberg SM, Helmer KG, Jann K, Jicha G, Rodriguez P, Satizabal CL, Seshadri S, Singh H, Thompson JF, Wang DJJ, Lu H. Multi-vendor and multisite evaluation of cerebrovascular reactivity mapping using hypercapnia challenge. Neuroimage 2021; 245:118754. [PMID: 34826595 PMCID: PMC8783393 DOI: 10.1016/j.neuroimage.2021.118754] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 11/05/2021] [Accepted: 11/22/2021] [Indexed: 01/22/2023] Open
Abstract
Cerebrovascular reactivity (CVR), which measures the ability of cerebral blood vessels to dilate or constrict in response to vasoactive stimuli such as CO2 inhalation, is an important index of the brain's vascular health. Quantification of CVR using BOLD MRI with hypercapnia challenge has shown great promises in research and clinical studies. However, in order for it to be used as a potential imaging biomarker in large-scale and multi-site studies, the reliability of CO2-CVR quantification across different MRI acquisition platforms and researchers/raters must be examined. The goal of this report from the MarkVCID small vessel disease biomarkers consortium is to evaluate the reliability of CO2-CVR quantification in three studies. First, the inter-rater reliability of CO2-CVR data processing was evaluated by having raters from 5 MarkVCID sites process the same 30 CVR datasets using a cloud-based CVR data processing pipeline. Second, the inter-scanner reproducibility of CO2-CVR quantification was assessed in 10 young subjects across two scanners of different vendors. Third, test-retest repeatability was evaluated in 20 elderly subjects from 4 sites with a scan interval of less than 2 weeks. In all studies, the CO2 CVR measurements were performed using the fixed inspiration method, where the subjects wore a nose clip and a mouthpiece and breathed room air and 5% CO2 air contained in a Douglas bag alternatively through their mouth. The results showed that the inter-rater CoV of CVR processing was 0.08 ± 0.08% for whole-brain CVR values and ranged from 0.16% to 0.88% in major brain regions, with ICC of absolute agreement above 0.9959 for all brain regions. Inter-scanner CoV was found to be 6.90 ± 5.08% for whole-brain CVR values, and ranged from 4.69% to 12.71% in major brain regions, which are comparable to intra-session CoVs obtained from the same scanners on the same day. ICC of consistency between the two scanners was 0.8498 for whole-brain CVR and ranged from 0.8052 to 0.9185 across major brain regions. In the test-retest evaluation, test-retest CoV across different days was found to be 18.29 ± 17.12% for whole-brain CVR values, and ranged from 16.58% to 19.52% in major brain regions, with ICC of absolute agreement ranged from 0.6480 to 0.7785. These results demonstrated good inter-rater, inter-scanner, and test-retest reliability in healthy volunteers, and suggested that CO2-CVR has suitable instrumental properties for use as an imaging biomarker of cerebrovascular function in multi-site and longitudinal observational studies and clinical trials.
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Affiliation(s)
- Peiying Liu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Dengrong Jiang
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Marilyn Albert
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | | | | | - Brian T Gold
- Department of Neuroscience, University of Kentucky, Lexington, KY, USA
| | - Steven M Greenberg
- Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Karl G Helmer
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
| | - Kay Jann
- Laboratory of Functional MRI Technology, Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Gregory Jicha
- Department of Neurology, University of Kentucky, Lexington, KY, USA
| | - Pavel Rodriguez
- Department of Radiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA; Glenn Biggs Institute for Alzheimer's and Neurodegenerative Diseases, UT Health San Antonio, San Antonio, TX, USA
| | - Claudia L Satizabal
- Glenn Biggs Institute for Alzheimer's and Neurodegenerative Diseases, UT Health San Antonio, San Antonio, TX, USA
| | - Sudha Seshadri
- Glenn Biggs Institute for Alzheimer's and Neurodegenerative Diseases, UT Health San Antonio, San Antonio, TX, USA
| | - Herpreet Singh
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
| | - Jeffrey F Thompson
- Department of Neurology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA
| | - Danny J J Wang
- Laboratory of Functional MRI Technology, Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Hanzhang Lu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore 21287, USA; F.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, 21205, USA.
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23
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Wang R, Oh JM, Motovylyak A, Ma Y, Sager MA, Rowley HA, Johnson KM, Gallagher CL, Carlsson CM, Bendlin BB, Johnson SC, Asthana S, Eisenmenger L, Okonkwo OC. Impact of sex and APOE ε4 on age-related cerebral perfusion trajectories in cognitively asymptomatic middle-aged and older adults: A longitudinal study. J Cereb Blood Flow Metab 2021; 41:3016-3027. [PMID: 34102919 PMCID: PMC8545048 DOI: 10.1177/0271678x211021313] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 03/16/2021] [Accepted: 03/20/2021] [Indexed: 01/03/2023]
Abstract
Cerebral hypoperfusion is thought to contribute to cognitive decline in Alzheimer's disease, but the natural trajectory of cerebral perfusion in cognitively healthy adults has not been well-studied. This longitudinal study is consisted of 950 participants (40-89 years), who were cognitively unimpaired at their first visit. We investigated the age-related changes in cerebral perfusion, and their associations with APOE-genotype, biological sex, and cardiometabolic measurements. During the follow-up period (range 0.13-8.24 years), increasing age was significantly associated with decreasing cerebral perfusion, in total gray-matter (β=-1.43), hippocampus (-1.25), superior frontal gyrus (-1.70), middle frontal gyrus (-1.99), posterior cingulate (-2.46), and precuneus (-2.14), with all P-values < 0.01. Compared with male-ɛ4 carriers, female-ɛ4 carriers showed a faster decline in global and regional cerebral perfusion with increasing age, whereas the age-related decline in cerebral perfusion was similar between male- and female-ɛ4 non-carriers. Worse cardiometabolic profile (i.e., increased blood pressure, body mass index, total cholesterol, and blood glucose) was associated with lower cerebral perfusion at all the visits. When time-varying cardiometabolic measurements were adjusted in the model, the synergistic effect of sex and APOE-ɛ4 on age-related cerebral perfusion-trajectories became largely attenuated. Our findings demonstrate that APOE-genotype and sex interactively impact cerebral perfusion-trajectories in mid- to late-life. This effect may be partially explained by cardiometabolic alterations.
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Affiliation(s)
- Rui Wang
- Wisconsin Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- The Swedish School of Sport and Health Science, GIH, Stockholm, Sweden
- Division of Clinical Geriatrics, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet and Stockholm University, Stockholm, Sweden
| | - Jennifer M Oh
- Wisconsin Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Geriatric Research Education and Clinical Center, William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
| | - Alice Motovylyak
- Wisconsin Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Yue Ma
- Wisconsin Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Mark A Sager
- Wisconsin Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Wisconsin Alzheimer’s Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Howard A Rowley
- Wisconsin Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Kevin M Johnson
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Catherine L Gallagher
- Wisconsin Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Geriatric Research Education and Clinical Center, William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
| | - Cynthia M Carlsson
- Wisconsin Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Geriatric Research Education and Clinical Center, William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
| | - Barbara B Bendlin
- Wisconsin Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Geriatric Research Education and Clinical Center, William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
- Wisconsin Alzheimer’s Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Sterling C Johnson
- Wisconsin Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Geriatric Research Education and Clinical Center, William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
- Wisconsin Alzheimer’s Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Sanjay Asthana
- Wisconsin Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Geriatric Research Education and Clinical Center, William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
| | - Laura Eisenmenger
- Wisconsin Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Ozioma C Okonkwo
- Wisconsin Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Geriatric Research Education and Clinical Center, William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
- Wisconsin Alzheimer’s Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
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24
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Sabra D, Intzandt B, Desjardins-Crepeau L, Langeard A, Steele CJ, Frouin F, Hoge RD, Bherer L, Gauthier CJ. Sex moderations in the relationship between aortic stiffness, cognition, and cerebrovascular reactivity in healthy older adults. PLoS One 2021; 16:e0257815. [PMID: 34582484 PMCID: PMC8478243 DOI: 10.1371/journal.pone.0257815] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 09/10/2021] [Indexed: 11/21/2022] Open
Abstract
It is well established that sex differences exist in the manifestation of vascular diseases. Arterial stiffness (AS) has been associated with changes in cerebrovascular reactivity (CVR) and cognitive decline in aging. Specifically, older adults with increased AS show a decline on executive function (EF) tasks. Interestingly, the relationship between AS and CVR is more complex, where some studies show decreased CVR with increased AS, and others demonstrate preserved CVR despite higher AS. Here, we investigated the possible role of sex on these hemodynamic relationships. Acquisitions were completed in 48 older adults. Pseudo-continuous arterial spin labeling (pCASL) data were collected during a hypercapnia challenge. Aortic pulse wave velocity (PWV) data was acquired using cine phase contrast velocity series. Cognitive function was assessed with a comprehensive neuropsychological battery, and a composite score for EF was calculated using four cognitive tests from the neuropsychological battery. A moderation model test revealed that sex moderated the relationship between PWV and CVR and PWV and EF, but not between CVR and EF. Together, our results indicate that the relationships between central stiffness, cerebral hemodynamics and cognition are in part mediated by sex.
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Affiliation(s)
- Dalia Sabra
- Faculty of Medicine, Department of Biomedical Science, Université de Montreal, Montreal, QC, Canada
- Research Center, Montreal Heart Institute, Montreal, QC, Canada
- Centre de recherche de l’Institut Universitaire de Gériatrie de Montréal (CRIUGM), Montréal, QC, Canada
- Department of Medicine, Universite de Montreal, Montreal, QC, Canada
| | - Brittany Intzandt
- Research Center, Montreal Heart Institute, Montreal, QC, Canada
- Centre de recherche de l’Institut Universitaire de Gériatrie de Montréal (CRIUGM), Montréal, QC, Canada
- PERFORM Centre, Concordia University, Montreal, QC, Canada
- INDI Department, Concordia University, Montreal, QC, Canada
| | - Laurence Desjardins-Crepeau
- Research Center, Montreal Heart Institute, Montreal, QC, Canada
- Centre de recherche de l’Institut Universitaire de Gériatrie de Montréal (CRIUGM), Montréal, QC, Canada
| | - Antoine Langeard
- Research Center, Montreal Heart Institute, Montreal, QC, Canada
- Centre de recherche de l’Institut Universitaire de Gériatrie de Montréal (CRIUGM), Montréal, QC, Canada
- Department of Medicine, Universite de Montreal, Montreal, QC, Canada
| | - Christopher J. Steele
- PERFORM Centre, Concordia University, Montreal, QC, Canada
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
- Department of Psychology, Concordia University, Montreal, QC, Canada
| | | | - Richard D. Hoge
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
- Montreal Neurological Institute, Montreal, QC, Canada
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
| | - Louis Bherer
- Research Center, Montreal Heart Institute, Montreal, QC, Canada
- Centre de recherche de l’Institut Universitaire de Gériatrie de Montréal (CRIUGM), Montréal, QC, Canada
- Department of Medicine, Universite de Montreal, Montreal, QC, Canada
| | - Claudine J. Gauthier
- Research Center, Montreal Heart Institute, Montreal, QC, Canada
- PERFORM Centre, Concordia University, Montreal, QC, Canada
- Physics Department, Concordia University, Montreal, QC, Canada
- * E-mail:
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25
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Graff BJ, Payne SJ, El-Bouri WK. The Ageing Brain: Investigating the Role of Age in Changes to the Human Cerebral Microvasculature With an in silico Model. Front Aging Neurosci 2021; 13:632521. [PMID: 34421568 PMCID: PMC8374868 DOI: 10.3389/fnagi.2021.632521] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 07/12/2021] [Indexed: 11/25/2022] Open
Abstract
Ageing causes extensive structural changes to the human cerebral microvasculature, which have a significant effect on capillary bed perfusion and oxygen transport. Current models of brain capillary networks in the literature focus on healthy adult brains and do not capture the effects of ageing, which is critical when studying neurodegenerative diseases. This study builds upon a statistically accurate model of the human cerebral microvasculature based on ex-vivo morphological data. This model is adapted for “healthy” ageing using in-vivo measurements from mice at three distinct age groups—young, middle-aged, and old. From this new model, blood and molecular exchange parameters are calculated such as permeability and surface-area-to-volume ratio, and compared across the three age groups. The ability to alter the model vessel-by-vessel is used to create a continuous gradient of ageing. It was found that surface-area-to-volume ratio reduced in old age by 6% and permeability by 24% from middle-age to old age, and variability within the networks also increased with age. The ageing gradient indicated a threshold in the ageing process around 75 years old, after which small changes have an amplified effect on blood flow properties. This gradient enables comparison of studies measuring cerebral properties at discrete points in time. The response of middle aged and old aged capillary beds to micro-emboli showed a lower robustness of the old age capillary bed to vessel occlusion. As the brain ages, there is thus increased vulnerability of the microvasculature—with a “tipping point” beyond which further remodeling of the microvasculature has exaggerated effects on the brain. When developing in-silico models of the brain, age is a very important consideration to accurately assess risk factors for cognitive decline and isolate early biomarkers of microvascular health.
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Affiliation(s)
- Barnaby J Graff
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, Oxford, United Kingdom
| | - Stephen J Payne
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, Oxford, United Kingdom
| | - Wahbi K El-Bouri
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, Oxford, United Kingdom.,Liverpool Centre for Cardiovascular Science, University of Liverpool & Liverpool Heart and Chest Hospital, Liverpool, United Kingdom.,Department of Cardiovascular and Metabolic Medicine, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, United Kingdom
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26
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Rajagopal S, Poddar R, Paul S. Tyrosine phosphatase STEP is a key regulator of glutamate-induced prostaglandin E 2 release from neurons. J Biol Chem 2021; 297:100944. [PMID: 34246631 PMCID: PMC8326425 DOI: 10.1016/j.jbc.2021.100944] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 06/23/2021] [Accepted: 07/07/2021] [Indexed: 12/30/2022] Open
Abstract
The neuron-specific tyrosine phosphatase striatal-enriched phosphatase (STEP) is emerging as a key regulator of excitotoxicity, which is involved in the pathogenesis of both acute and chronic neurological diseases. However, the intracellular mechanisms that are regulated by STEP to confer neuroprotection against excitotoxic insults are not well understood. The present study investigates the role of STEP in regulating neuronal release of the proinflammatory prostanoid prostaglandin E2 (PGE2), which is associated with a wide range of pathological conditions. The findings show that glutamate-mediated activation of the N-methyl-D-aspartic acid receptor in STEP-deficient neurons leads to rapid and sustained increase in the phosphorylation of p38 mitogen-activated protein kinase (p38 MAPK), a signaling molecule involved in the production of inflammatory mediators. Such sustained p38 MAPK activation increases the activity of cytosolic phospholipase A2, which catalyzes the release of arachidonic acid, the initial substrate for PGE2 biosynthesis. Sustained p38 MAPK activation also induces nuclear factor-κB-mediated increase in expression of cyclooxygenase-2 that is involved in the conversion of arachidonic acid to prostanoids, resulting in enhanced biosynthesis and release of PGE2 from neurons. Restoration of STEP function with a STEP mimetic (TAT-STEP-myc peptide) significantly decreases the activation of p38 MAPK-mediated cytosolic phospholipase A2/cyclooxygenase-2/PGE2 signaling cascade. This study identifies an important mechanism involved in the neuronal release of the proinflammatory mediator PGE2 after excitotoxic insult and highlights for the first time the immunomodulatory ability of a neuronal tyrosine phosphatase.
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Affiliation(s)
- Sathyanarayanan Rajagopal
- Department of Neurology, University of New Mexico Health Sciences Center, University of New Mexico, Albuquerque, New Mexico, USA
| | - Ranjana Poddar
- Department of Neurology, University of New Mexico Health Sciences Center, University of New Mexico, Albuquerque, New Mexico, USA
| | - Surojit Paul
- Department of Neurology, University of New Mexico Health Sciences Center, University of New Mexico, Albuquerque, New Mexico, USA.
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27
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Yabluchanskiy A, Nyul-Toth A, Csiszar A, Gulej R, Saunders D, Towner R, Turner M, Zhao Y, Abdelkari D, Rypma B, Tarantini S. Age-related alterations in the cerebrovasculature affect neurovascular coupling and BOLD fMRI responses: Insights from animal models of aging. Psychophysiology 2021; 58:e13718. [PMID: 33141436 PMCID: PMC9166153 DOI: 10.1111/psyp.13718] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 08/10/2020] [Accepted: 09/28/2020] [Indexed: 12/11/2022]
Abstract
The present and future research efforts in cognitive neuroscience and psychophysiology rely on the measurement, understanding, and interpretation of blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) to effectively investigate brain function. Aging and age-associated pathophysiological processes change the structural and functional integrity of the cerebrovasculature which can significantly alter how the BOLD signal is recorded and interpreted. In order to gain an improved understanding of the benefits, drawbacks, and methodological implications for BOLD fMRI in the context of cognitive neuroscience, it is crucial to understand the cellular and molecular mechanism of age-related vascular pathologies. This review discusses the multifaceted effects of aging and the contributions of age-related pathologies on structural and functional integrity of the cerebral microcirculation as they has been investigated in animal models of aging, including age-related alterations in neurovascular coupling responses, cellular and molecular mechanisms involved in microvascular damage, vascular rarefaction, blood-brain barrier disruption, senescence, humoral deficiencies as they relate to, and potentially introduce confounding factors in the interpretation of BOLD fMRI.
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Affiliation(s)
- Andriy Yabluchanskiy
- Vascular Cognitive Impairment and Neurodegeneration Program, Oklahoma Center for Geroscience and Healthy Brain Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Adam Nyul-Toth
- Vascular Cognitive Impairment and Neurodegeneration Program, Oklahoma Center for Geroscience and Healthy Brain Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA,Institute of Biophysics, Biological Research Centre, Szeged, Hungary
| | - Anna Csiszar
- Vascular Cognitive Impairment and Neurodegeneration Program, Oklahoma Center for Geroscience and Healthy Brain Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Rafal Gulej
- Advanced Magnetic Resonance Center, Oklahoma Medical Research Foundation, Oklahoma, OK, USA
| | - Debra Saunders
- Advanced Magnetic Resonance Center, Oklahoma Medical Research Foundation, Oklahoma, OK, USA
| | - Rheal Towner
- Advanced Magnetic Resonance Center, Oklahoma Medical Research Foundation, Oklahoma, OK, USA
| | - Monroe Turner
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, TX, USA
| | - Yuguang Zhao
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, TX, USA
| | - Dema Abdelkari
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, TX, USA
| | - Bart Rypma
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, TX, USA,Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Stefano Tarantini
- Vascular Cognitive Impairment and Neurodegeneration Program, Oklahoma Center for Geroscience and Healthy Brain Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA,International Training Program in Geroscience, Doctoral School of Basic and Translational Medicine/Department of Public Health, Semmelweis University, Budapest, Hungary,Department of Health Promotion Sciences, College of Public Health, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
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28
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Zimmerman B, Rypma B, Gratton G, Fabiani M. Age-related changes in cerebrovascular health and their effects on neural function and cognition: A comprehensive review. Psychophysiology 2021; 58:e13796. [PMID: 33728712 PMCID: PMC8244108 DOI: 10.1111/psyp.13796] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 01/11/2021] [Accepted: 02/08/2021] [Indexed: 12/11/2022]
Abstract
The process of aging includes changes in cellular biology that affect local interactions between cells and their environments and eventually propagate to systemic levels. In the brain, where neurons critically depend on an efficient and dynamic supply of oxygen and glucose, age-related changes in the complex interaction between the brain parenchyma and the cerebrovasculature have effects on health and functioning that negatively impact cognition and play a role in pathology. Thus, cerebrovascular health is considered one of the main mechanisms by which a healthy lifestyle, such as habitual cardiorespiratory exercise and a healthful diet, could lead to improved cognitive outcomes with aging. This review aims at detailing how the physiology of the cerebral vascular system changes with age and how these changes lead to differential trajectories of cognitive maintenance or decline. This provides a framework for generating specific mechanistic hypotheses about the efficacy of proposed interventions and lifestyle covariates that contribute to enhanced cognitive well-being. Finally, we discuss the methodological implications of age-related changes in the cerebral vasculature for human cognitive neuroscience research and propose directions for future experiments aimed at investigating age-related changes in the relationship between physiology and cognitive mechanisms.
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Affiliation(s)
- Benjamin Zimmerman
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Bart Rypma
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX, USA
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Gabriele Gratton
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Psychology, University of Illinois at Urbana-Champaign, Champaign, IL, USA
- Neuroscience Program, University of Illinois at Urbana-Champaign, Champaign, IL, USA
| | - Monica Fabiani
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Psychology, University of Illinois at Urbana-Champaign, Champaign, IL, USA
- Neuroscience Program, University of Illinois at Urbana-Champaign, Champaign, IL, USA
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29
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Zhao Y, Liu P, Turner MP, Abdelkarim D, Lu H, Rypma B. The neural-vascular basis of age-related processing speed decline. Psychophysiology 2021; 58:e13845. [PMID: 34115388 DOI: 10.1111/psyp.13845] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 04/14/2021] [Accepted: 04/19/2021] [Indexed: 12/12/2022]
Abstract
Most studies examining neurocognitive aging are based on the blood-oxygen level-dependent signal obtained during functional magnetic resonance imaging (fMRI). The physiological basis of this signal is neural-vascular coupling, the process by which neurons signal cerebrovasculature to dilate in response to an increase in active neural metabolism due to stimulation. These fMRI studies of aging rely on the hemodynamic equivalence assumption that this process is not disrupted by physiologic deterioration associated with aging. Studies of neural-vascular coupling challenge this assumption and show that neural-vascular coupling is closely related to cognition. In this review, we put forward a theory of processing speed decline in aging and how it is related to age-related neural-vascular coupling changes based on the results of studies elucidating the relationships between cognition, cerebrovascular dynamics, and aging.
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Affiliation(s)
- Yuguang Zhao
- School of Behavioral and Brain Sciences, Center for Brain Health, University of Texas at Dallas, Richardson, TX, USA
| | - Peiying Liu
- School of Medicine, Department of Radiology, Johns Hopkins University, Baltimore, MD, USA
| | - Monroe P Turner
- School of Behavioral and Brain Sciences, Center for Brain Health, University of Texas at Dallas, Richardson, TX, USA
| | - Dema Abdelkarim
- School of Behavioral and Brain Sciences, Center for Brain Health, University of Texas at Dallas, Richardson, TX, USA
| | - Hanzhang Lu
- School of Medicine, Department of Radiology, Johns Hopkins University, Baltimore, MD, USA
| | - Bart Rypma
- School of Behavioral and Brain Sciences, Center for Brain Health, University of Texas at Dallas, Richardson, TX, USA
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30
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Nogueira RC, Beishon L, Bor-Seng-Shu E, Panerai RB, Robinson TG. Cerebral Autoregulation in Ischemic Stroke: From Pathophysiology to Clinical Concepts. Brain Sci 2021; 11:511. [PMID: 33923721 PMCID: PMC8073938 DOI: 10.3390/brainsci11040511] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 04/02/2021] [Accepted: 04/09/2021] [Indexed: 11/17/2022] Open
Abstract
Ischemic stroke (IS) is one of the most impacting diseases in the world. In the last decades, new therapies have been introduced to improve outcomes after IS, most of them aiming for recanalization of the occluded vessel. However, despite this advance, there are still a large number of patients that remain disabled. One interesting possible therapeutic approach would be interventions guided by cerebral hemodynamic parameters such as dynamic cerebral autoregulation (dCA). Supportive hemodynamic therapies aiming to optimize perfusion in the ischemic area could protect the brain and may even extend the therapeutic window for reperfusion therapies. However, the knowledge of how to implement these therapies in the complex pathophysiology of brain ischemia is challenging and still not fully understood. This comprehensive review will focus on the state of the art in this promising area with emphasis on the following aspects: (1) pathophysiology of CA in the ischemic process; (2) methodology used to evaluate CA in IS; (3) CA studies in IS patients; (4) potential non-reperfusion therapies for IS patients based on the CA concept; and (5) the impact of common IS-associated comorbidities and phenotype on CA status. The review also points to the gaps existing in the current research to be further explored in future trials.
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Affiliation(s)
- Ricardo C. Nogueira
- Neurology Department, School of Medicine, Hospital das Clinicas, University of São Paulo, São Paulo 01246-904, Brazil;
- Department of Neurology, Hospital Nove de Julho, São Paulo 01409-002, Brazil
| | - Lucy Beishon
- Cerebral Haemodynamics in Ageing and Stroke Medicine Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester LE2 7LX, UK; (L.B.); (R.B.P.); (T.G.R.)
| | - Edson Bor-Seng-Shu
- Neurology Department, School of Medicine, Hospital das Clinicas, University of São Paulo, São Paulo 01246-904, Brazil;
| | - Ronney B. Panerai
- Cerebral Haemodynamics in Ageing and Stroke Medicine Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester LE2 7LX, UK; (L.B.); (R.B.P.); (T.G.R.)
- National Institute for Health Research (NIHR) Leicester Biomedical Research Centre, University of Leicester, Leicester LE5 4PW, UK
| | - Thompson G. Robinson
- Cerebral Haemodynamics in Ageing and Stroke Medicine Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester LE2 7LX, UK; (L.B.); (R.B.P.); (T.G.R.)
- National Institute for Health Research (NIHR) Leicester Biomedical Research Centre, University of Leicester, Leicester LE5 4PW, UK
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Chen JJ, Gauthier CJ. The Role of Cerebrovascular-Reactivity Mapping in Functional MRI: Calibrated fMRI and Resting-State fMRI. Front Physiol 2021; 12:657362. [PMID: 33841190 PMCID: PMC8027080 DOI: 10.3389/fphys.2021.657362] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 03/02/2021] [Indexed: 12/14/2022] Open
Abstract
Task and resting-state functional MRI (fMRI) is primarily based on the same blood-oxygenation level-dependent (BOLD) phenomenon that MRI-based cerebrovascular reactivity (CVR) mapping has most commonly relied upon. This technique is finding an ever-increasing role in neuroscience and clinical research as well as treatment planning. The estimation of CVR has unique applications in and associations with fMRI. In particular, CVR estimation is part of a family of techniques called calibrated BOLD fMRI, the purpose of which is to allow the mapping of cerebral oxidative metabolism (CMRO2) using a combination of BOLD and cerebral-blood flow (CBF) measurements. Moreover, CVR has recently been shown to be a major source of vascular bias in computing resting-state functional connectivity, in much the same way that it is used to neutralize the vascular contribution in calibrated fMRI. Furthermore, due to the obvious challenges in estimating CVR using gas challenges, a rapidly growing field of study is the estimation of CVR without any form of challenge, including the use of resting-state fMRI for that purpose. This review addresses all of these aspects in which CVR interacts with fMRI and the role of CVR in calibrated fMRI, provides an overview of the physiological biases and assumptions underlying hypercapnia-based CVR and calibrated fMRI, and provides a view into the future of non-invasive CVR measurement.
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Affiliation(s)
- J Jean Chen
- Baycrest Centre for Geriatric Care, Rotman Research Institute, Toronto, ON, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Claudine J Gauthier
- Department of Physics, Concordia University, Montreal, QC, Canada.,Montreal Heart Institute, Montreal, QC, Canada
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32
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Sleight E, Stringer MS, Marshall I, Wardlaw JM, Thrippleton MJ. Cerebrovascular Reactivity Measurement Using Magnetic Resonance Imaging: A Systematic Review. Front Physiol 2021; 12:643468. [PMID: 33716793 PMCID: PMC7947694 DOI: 10.3389/fphys.2021.643468] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 02/01/2021] [Indexed: 12/27/2022] Open
Abstract
Cerebrovascular reactivity (CVR) magnetic resonance imaging (MRI) probes cerebral haemodynamic changes in response to a vasodilatory stimulus. CVR closely relates to the health of the vasculature and is therefore a key parameter for studying cerebrovascular diseases such as stroke, small vessel disease and dementias. MRI allows in vivo measurement of CVR but several different methods have been presented in the literature, differing in pulse sequence, hardware requirements, stimulus and image processing technique. We systematically reviewed publications measuring CVR using MRI up to June 2020, identifying 235 relevant papers. We summarised the acquisition methods, experimental parameters, hardware and CVR quantification approaches used, clinical populations investigated, and corresponding summary CVR measures. CVR was investigated in many pathologies such as steno-occlusive diseases, dementia and small vessel disease and is generally lower in patients than in healthy controls. Blood oxygen level dependent (BOLD) acquisitions with fixed inspired CO2 gas or end-tidal CO2 forcing stimulus are the most commonly used methods. General linear modelling of the MRI signal with end-tidal CO2 as the regressor is the most frequently used method to compute CVR. Our survey of CVR measurement approaches and applications will help researchers to identify good practice and provide objective information to inform the development of future consensus recommendations.
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Affiliation(s)
- Emilie Sleight
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom
| | - Michael S. Stringer
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom,*Correspondence: Michael S. Stringer
| | - Ian Marshall
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom
| | - Joanna M. Wardlaw
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom
| | - Michael J. Thrippleton
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom
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33
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Champagne AA, Bhogal AA. Insights Into Cerebral Tissue-Specific Response to Respiratory Challenges at 7T: Evidence for Combined Blood Flow and CO 2-Mediated Effects. Front Physiol 2021; 12:601369. [PMID: 33584344 PMCID: PMC7876301 DOI: 10.3389/fphys.2021.601369] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 01/06/2021] [Indexed: 11/16/2022] Open
Abstract
Cerebrovascular reactivity (CVR) mapping is finding increasing clinical applications as a non-invasive probe for vascular health. Further analysis extracting temporal delay information from the CVR response provide additional insight that reflect arterial transit time, blood redistribution, and vascular response speed. Untangling these factors can help better understand the (patho)physiology and improve diagnosis/prognosis associated with vascular impairments. Here, we use hypercapnic (HC) and hyperoxic (HO) challenges to gather insight about factors driving temporal delays between gray-matter (GM) and white-matter (WM). Blood Oxygen Level Dependent (BOLD) datasets were acquired at 7T in nine healthy subjects throughout BLOCK- and RAMP-HC paradigms. In a subset of seven participants, a combined HC+HO block, referred as the “BOOST” protocol, was also acquired. Tissue-based differences in Rapid Interpolation at Progressive Time Delays (RIPTiDe) were compared across stimulus to explore dynamic (BLOCK-HC) versus progressive (RAMP-HC) changes in CO2, as well as the effect of bolus arrival time on CVR delays (BLOCK-HC versus BOOST). While GM delays were similar between the BLOCK- (21.80 ± 10.17 s) and RAMP-HC (24.29 ± 14.64 s), longer WM lag times were observed during the RAMP-HC (42.66 ± 17.79 s), compared to the BLOCK-HC (34.15 ± 10.72 s), suggesting that the progressive stimulus may predispose WM vasculature to longer delays due to the smaller arterial content of CO2 delivered to WM tissues, which in turn, decreases intravascular CO2 gradients modulating CO2 diffusion into WM tissues. This was supported by a maintained ∼10 s offset in GM (11.66 ± 9.54 s) versus WM (21.40 ± 11.17 s) BOOST-delays with respect to the BLOCK-HC, suggesting that the vasoactive effect of CO2 remains constant and that shortening of BOOST delays was be driven by blood arrival reflected through the non-vasodilatory HO contrast. These findings support that differences in temporal and magnitude aspects of CVR between vascular networks reflect a component of CO2 sensitivity, in addition to redistribution and steal blood flow effects. Moreover, these results emphasize that the addition of a BOOST paradigm may provide clinical insights into whether vascular diseases causing changes in CVR do so by way of severe blood flow redistribution effects, alterations in vascular properties associated with CO2 diffusion, or changes in blood arrival time.
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Affiliation(s)
- Allen A Champagne
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada.,School of Medicine, Queen's University, Kingston, ON, Canada
| | - Alex A Bhogal
- Department of Radiology, University Medical Center Utrecht, Utrecht, Netherlands
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34
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Leidhin CN, McMorrow J, Carey D, Newman L, Williamson W, Fagan AJ, Chappell MA, Kenny RA, Meaney JF, Knight SP. Age-related normative changes in cerebral perfusion: Data from The Irish Longitudinal Study on Ageing (TILDA). Neuroimage 2021; 229:117741. [PMID: 33454406 DOI: 10.1016/j.neuroimage.2021.117741] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 12/27/2020] [Accepted: 01/09/2021] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVE To establish normative reference values for total grey matter cerebral blood flow (CBFGM) measured using pseudo-continuous arterial spin labelling (pCASL) MRI in a large cohort of community-dwelling adults aged 54 years and older. BACKGROUND Quantitative assessment of CBFGM may provide an imaging biomarker for the early detection of those at risk of neurodegenerative diseases, such as Alzheimer's and dementia. However, the use of this method to differentiate normal age-related decline in CBFGM from pathological reduction has been hampered by the lack of reference values for cerebral perfusion. METHODS The study cohort comprised a subset of wave 3 (2014-2015) participants from The Irish Longitudinal Study on Ageing (TILDA), a large-scale prospective cohort study of individuals aged 50 and over. Of 4309 participants attending for health centre assessment, 578 individuals returned for 3T multi-parametric MRI brain examinations. In total, CBFGM data acquired from 468 subjects using pCASL-MRI were included in this analysis. Normative values were estimated using Generalised Additive Models for Location Shape and Scale (GAMLSS) and are presented as percentiles, means and standard deviations. RESULTS The mean age of the cohort was 68.2 ± 6.9 years and 51.7% were female. Mean CBFGM for the cohort was 36.5 ± 8.2 ml/100 g/min. CBFGM decreased by 0.2 ml/100 g/min for each year increase in age (95% CI = -0.3, -0.1; p ≤ 0.001) and was 3.1 ml/100 g/min higher in females (95% CI = 1.6, 4.5; p ≤ 0.001). CONCLUSIONS This study is by far the largest single-site study focused on an elderly community-dwelling cohort to present normative reference values for CBFGM measured at 3T using pCASL-MRI. Significant age- and sex-related differences exist in CBFGM.
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Affiliation(s)
- Caoilfhionn Ní Leidhin
- School of Medicine, Trinity College Dublin, Ireland; The National Centre for Advanced Medical Imaging (CAMI), St. James's Hospital, Dublin, Ireland
| | - Jason McMorrow
- School of Medicine, Trinity College Dublin, Ireland; The National Centre for Advanced Medical Imaging (CAMI), St. James's Hospital, Dublin, Ireland
| | - Daniel Carey
- School of Medicine, Trinity College Dublin, Ireland; The Irish Longitudinal Study on Ageing (TILDA), Trinity College Dublin, Ireland
| | - Louise Newman
- School of Medicine, Trinity College Dublin, Ireland; The Irish Longitudinal Study on Ageing (TILDA), Trinity College Dublin, Ireland
| | - Wilby Williamson
- School of Medicine, Trinity College Dublin, Ireland; The Global Brain Health Institute (GBHI), Trinity College Dublin, Ireland
| | - Andrew J Fagan
- Department of Radiology, Mayo Clinic, Rochester, MN, USA
| | - Michael A Chappell
- Radiological Sciences, Division of Clinical Neuroscience, School of Medicine, University of Nottingham, Nottingham, United Kingdom; Sir Peter Mansfield Imaging Center, School of Medicine, University of Nottingham, Nottingham, United Kingdom; Nottingham Biomedical Research Centre, Queens Medical Centre, University of Nottingham, Nottingham, United Kingdom; Wellcome Centre for Integrative Neuroimaging, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Rose Anne Kenny
- School of Medicine, Trinity College Dublin, Ireland; The Irish Longitudinal Study on Ageing (TILDA), Trinity College Dublin, Ireland; The Global Brain Health Institute (GBHI), Trinity College Dublin, Ireland; Mercer's Institute for Successful Ageing, St. James's Hospital, Dublin, Ireland
| | - James F Meaney
- School of Medicine, Trinity College Dublin, Ireland; The National Centre for Advanced Medical Imaging (CAMI), St. James's Hospital, Dublin, Ireland
| | - Silvin P Knight
- School of Medicine, Trinity College Dublin, Ireland; The Irish Longitudinal Study on Ageing (TILDA), Trinity College Dublin, Ireland.
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Tsvetanov KA, Henson RNA, Rowe JB. Separating vascular and neuronal effects of age on fMRI BOLD signals. Philos Trans R Soc Lond B Biol Sci 2021; 376:20190631. [PMID: 33190597 PMCID: PMC7741031 DOI: 10.1098/rstb.2019.0631] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/19/2020] [Indexed: 12/14/2022] Open
Abstract
Accurate identification of brain function is necessary to understand the neurobiology of cognitive ageing, and thereby promote well-being across the lifespan. A common tool used to investigate neurocognitive ageing is functional magnetic resonance imaging (fMRI). However, although fMRI data are often interpreted in terms of neuronal activity, the blood oxygenation level-dependent (BOLD) signal measured by fMRI includes contributions of both vascular and neuronal factors, which change differentially with age. While some studies investigate vascular ageing factors, the results of these studies are not well known within the field of neurocognitive ageing and therefore vascular confounds in neurocognitive fMRI studies are common. Despite over 10 000 BOLD-fMRI papers on ageing, fewer than 20 have applied techniques to correct for vascular effects. However, neurovascular ageing is not only a confound in fMRI, but an important feature in its own right, to be assessed alongside measures of neuronal ageing. We review current approaches to dissociate neuronal and vascular components of BOLD-fMRI of regional activity and functional connectivity. We highlight emerging evidence that vascular mechanisms in the brain do not simply control blood flow to support the metabolic needs of neurons, but form complex neurovascular interactions that influence neuronal function in health and disease. This article is part of the theme issue 'Key relationships between non-invasive functional neuroimaging and the underlying neuronal activity'.
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Affiliation(s)
- Kamen A. Tsvetanov
- Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0SZ, UK
- Department of Psychology, University of Cambridge, Cambridge CB2 3EB, UK
| | - Richard N. A. Henson
- Department of Psychiatry, University of Cambridge, Cambridge CB2 0SP, UK
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
| | - James B. Rowe
- Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0SZ, UK
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
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36
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Candelario-Jalil E, Paul S. Impact of aging and comorbidities on ischemic stroke outcomes in preclinical animal models: A translational perspective. Exp Neurol 2021; 335:113494. [PMID: 33035516 PMCID: PMC7874968 DOI: 10.1016/j.expneurol.2020.113494] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 09/25/2020] [Accepted: 10/02/2020] [Indexed: 12/16/2022]
Abstract
Ischemic stroke is a highly complex and devastating neurological disease. The sudden loss of blood flow to a brain region due to an ischemic insult leads to severe damage to that area resulting in the formation of an infarcted tissue, also known as the ischemic core. This is surrounded by the peri-infarct region or penumbra that denotes the functionally impaired but potentially salvageable tissue. Thus, the penumbral tissue is the main target for the development of neuroprotective strategies to minimize the extent of ischemic brain damage by timely therapeutic intervention. Given the limitations of reperfusion therapies with recombinant tissue plasminogen activator or mechanical thrombectomy, there is high enthusiasm to combine reperfusion therapy with neuroprotective strategies to further reduce the progression of ischemic brain injury. Till date, a large number of candidate neuroprotective drugs have been identified as potential therapies based on highly promising results from studies in rodent ischemic stroke models. However, none of these interventions have shown therapeutic benefits in stroke patients in clinical trials. In this review article, we discussed the urgent need to utilize preclinical models of ischemic stroke that more accurately mimic the clinical conditions in stroke patients by incorporating aged animals and animal stroke models with comorbidities. We also outlined the recent findings that highlight the significant differences in stroke outcome between young and aged animals, and how major comorbid conditions such as hypertension, diabetes, obesity and hyperlipidemia dramatically increase the vulnerability of the brain to ischemic damage that eventually results in worse functional outcomes. It is evident from these earlier studies that including animal models of aging and comorbidities during the early stages of drug development could facilitate the identification of neuroprotective strategies with high likelihood of success in stroke clinical trials.
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Affiliation(s)
- Eduardo Candelario-Jalil
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA.
| | - Surojit Paul
- Department of Neurology, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
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37
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Delli Pizzi S, Granzotto A, Bomba M, Frazzini V, Onofrj M, Sensi SL. Acting Before; A Combined Strategy to Counteract the Onset and Progression of Dementia. Curr Alzheimer Res 2020; 17:790-804. [PMID: 33272186 DOI: 10.2174/1567205017666201203085524] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Revised: 09/10/2020] [Accepted: 10/16/2020] [Indexed: 11/22/2022]
Abstract
Brain aging and aging-related neurodegenerative disorders are posing a significant challenge for health systems worldwide. To date, most of the therapeutic efforts aimed at counteracting dementiarelated behavioral and cognitive impairment have been focused on addressing putative determinants of the disease, such as β-amyloid or tau. In contrast, relatively little attention has been paid to pharmacological interventions aimed at restoring or promoting the synaptic plasticity of the aging brain. The review will explore and discuss the most recent molecular, structural/functional, and behavioral evidence that supports the use of non-pharmacological approaches as well as cognitive-enhancing drugs to counteract brain aging and early-stage dementia.
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Affiliation(s)
- Stefano Delli Pizzi
- Behavioral Neurology and Molecular Neurology Units, Center for Advanced Studies and Technology, CAST, University G. d'Annunzio of Chieti-Pescara, Pescara, Italy
| | - Alberto Granzotto
- Behavioral Neurology and Molecular Neurology Units, Center for Advanced Studies and Technology, CAST, University G. d'Annunzio of Chieti-Pescara, Pescara, Italy
| | - Manuela Bomba
- Behavioral Neurology and Molecular Neurology Units, Center for Advanced Studies and Technology, CAST, University G. d'Annunzio of Chieti-Pescara, Pescara, Italy
| | - Valerio Frazzini
- AP-HP, Epilepsy Unit, Pitie-Salpetriere Hospital and Brain and Spine Institute (INSERM UMRS1127, CNRS UMR7225, Sorbonne Universite), Pitie-Salpetriere Hospital, Paris, France
| | - Marco Onofrj
- Behavioral Neurology and Molecular Neurology Units, Center for Advanced Studies and Technology, CAST, University G. d'Annunzio of Chieti-Pescara, Pescara, Italy
| | - Stefano L Sensi
- Behavioral Neurology and Molecular Neurology Units, Center for Advanced Studies and Technology, CAST, University G. d'Annunzio of Chieti-Pescara, Pescara, Italy
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Archila-Meléndez ME, Sorg C, Preibisch C. Modeling the impact of neurovascular coupling impairments on BOLD-based functional connectivity at rest. Neuroimage 2020; 218:116871. [DOI: 10.1016/j.neuroimage.2020.116871] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 04/17/2020] [Accepted: 04/20/2020] [Indexed: 12/12/2022] Open
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Taneja K, Liu P, Xu C, Turner M, Zhao Y, Abdelkarim D, Thomas BP, Rypma B, Lu H. Quantitative Cerebrovascular Reactivity in Normal Aging: Comparison Between Phase-Contrast and Arterial Spin Labeling MRI. Front Neurol 2020; 11:758. [PMID: 32849217 PMCID: PMC7411174 DOI: 10.3389/fneur.2020.00758] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 06/19/2020] [Indexed: 12/20/2022] Open
Abstract
Purpose: Cerebrovascular reactivity (CVR) is an index of the dilatory function of cerebral blood vessels and has shown great promise in the diagnosis of risk factors in cerebrovascular disease. Aging is one such risk factor; thus, it is important to characterize age-related differences in CVR. CVR can be measured by BOLD MRI but few studies have measured quantitative cerebral blood flow (CBF)-based CVR in the context of aging. This study aims to determine the age effect on CVR using two quantitative CBF techniques, phase-contrast (PC), and arterial spin labeling (ASL) MRI. Methods: In 49 participants (32 younger and 17 older), CVR was measured with PC, ASL, and BOLD MRI. These CVR methods were compared across young and older groups to determine their dependence on age. PC and ASL CVR were also studied for inter-correlation and mean differences. Gray and white matter CVR values were also studied. Results: PC CVR was higher in younger participants than older participants (by 17%, p = 0.046). However, there were no age differences in ASL or BOLD CVR. ASL CVR was significantly correlated with PC CVR (p = 0.042) and BOLD CVR (p = 0.016), but its values were underestimated compared to PC CVR (p = 0.045). ASL CVR map revealed no difference between gray matter and white matter tissue types, whereas gray matter was significantly higher than white matter in the BOLD CVR map. Conclusion: This study compared two quantitative CVR techniques in the context of brain aging and revealed that PC CVR is a more sensitive method for detection of age differences, despite the absence of spatial information. The ASL method showed a significant correlation with PC and BOLD, but it tends to underestimate CVR due to confounding factors associated with this technique. Importantly, our data suggest that there is not a difference in CBF-based CVR between the gray and white matter, in contrast to previous observation using BOLD MRI.
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Affiliation(s)
- Kamil Taneja
- The Russel H. Morgan Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Peiying Liu
- The Russel H. Morgan Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Cuimei Xu
- The Russel H. Morgan Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Monroe Turner
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX, United States
| | - Yuguang Zhao
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX, United States
| | - Dema Abdelkarim
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX, United States
| | - Binu P Thomas
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Bart Rypma
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX, United States.,Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Hanzhang Lu
- The Russel H. Morgan Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, United States.,Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, United States
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40
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Intzandt B, Sabra D, Foster C, Desjardins-Crépeau L, Hoge RD, Steele CJ, Bherer L, Gauthier CJ. Higher cardiovascular fitness level is associated with lower cerebrovascular reactivity and perfusion in healthy older adults. J Cereb Blood Flow Metab 2020; 40:1468-1481. [PMID: 31342831 PMCID: PMC7308519 DOI: 10.1177/0271678x19862873] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 06/02/2019] [Indexed: 01/01/2023]
Abstract
Aging is accompanied by vascular and structural changes in the brain, which include decreased grey matter volume (GMV), cerebral blood flow (CBF), and cerebrovascular reactivity (CVR). Enhanced fitness in aging has been related to preservation of GMV and CBF, and in some cases CVR, although there are contradictory relationships reported between CVR and fitness. To gain a better understanding of the complex interplay between fitness and GMV, CBF and CVR, the present study assessed these factors concurrently. Data from 50 participants, aged 55 to 72, were used to derive GMV, CBF, CVR and VO2peak. Results revealed that lower CVR was associated with higher VO2peak throughout large areas of the cerebral cortex. Within these regions lower fitness was associated with higher CBF and a faster hemodynamic response to hypercapnia. Overall, our results indicate that the relationships between age, fitness, cerebral health and cerebral hemodynamics are complex, likely involving changes in chemosensitivity and autoregulation in addition to changes in arterial stiffness. Future studies should collect other physiological outcomes in parallel with quantitative imaging, such as measures of chemosensitivity and autoregulation, to further understand the intricate effects of fitness on the aging brain, and how this may bias quantitative measures of cerebral health.
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Affiliation(s)
- Brittany Intzandt
- INDI Department, Concordia University,
Montreal, Canada
- PERFORM Centre, Concordia University,
Montreal, Canada
- Centre de Recherche de l'Institut
Universitaire de Gériatrie de Montréal, Montreal, Canada
| | - Dalia Sabra
- Départment de Médecine, Université de
Montréal, Canada
| | - Catherine Foster
- PERFORM Centre, Concordia University,
Montreal, Canada
- Physics Department, Concordia
University, Montreal, Canada
| | - Laurence Desjardins-Crépeau
- Centre de Recherche de l'Institut
Universitaire de Gériatrie de Montréal, Montreal, Canada
- Centre de Recherche de l'Institut de
Cardiologie de Montréal, Montréal, Canada
| | - Richard D Hoge
- Department of Neurology and
Neurosurgery, McGill University, Canada
| | - Christopher J Steele
- Department of Psychology, Concordia
University, Montreal, Canada
- Department of Neurology, Max Planck
Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Louis Bherer
- PERFORM Centre, Concordia University,
Montreal, Canada
- Centre de Recherche de l'Institut
Universitaire de Gériatrie de Montréal, Montreal, Canada
- Départment de Médecine, Université de
Montréal, Canada
- Centre de Recherche de l'Institut de
Cardiologie de Montréal, Montréal, Canada
| | - Claudine J Gauthier
- PERFORM Centre, Concordia University,
Montreal, Canada
- Physics Department, Concordia
University, Montreal, Canada
- Centre de Recherche de l'Institut de
Cardiologie de Montréal, Montréal, Canada
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Jiang D, Lin Z, Liu P, Sur S, Xu C, Hazel K, Pottanat G, Yasar S, Rosenberg P, Albert M, Lu H. Normal variations in brain oxygen extraction fraction are partly attributed to differences in end-tidal CO 2. J Cereb Blood Flow Metab 2020; 40:1492-1500. [PMID: 31382788 PMCID: PMC7308520 DOI: 10.1177/0271678x19867154] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Cerebral oxygen extraction fraction is an important physiological index of the brain's oxygen consumption and supply and has been suggested to be a potential biomarker for a number of diseases such as stroke, Alzheimer's disease, multiple sclerosis, sickle cell disease, and metabolic disorders. However, in order for oxygen extraction fraction to be a sensitive biomarker for personalized disease diagnosis, inter-subject variations in normal subjects must be minimized or accounted for, which will otherwise obscure its interpretation. Therefore, it is essential to investigate the physiological underpinnings of normal differences in oxygen extraction fraction. This work used two studies, one discovery study and one verification study, to examine the extent to which an individual's end-tidal CO2 can explain variations in oxygen extraction fraction. It was found that, across normal subjects, oxygen extraction fraction is inversely correlated with end-tidal CO2. Approximately 50% of the inter-subject variations in oxygen extraction fraction can be attributed to end-tidal CO2 differences. In addition, oxygen extraction fraction was found to be positively associated with age and systolic blood pressure. By accounting for end-tidal CO2, age, and systolic blood pressure of the subjects, normal variations in oxygen extraction fraction can be reduced by 73%, which is expected to substantially enhance the utility of oxygen extraction fraction as a disease biomarker.
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Affiliation(s)
- Dengrong Jiang
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Zixuan Lin
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Peiying Liu
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Sandeepa Sur
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Cuimei Xu
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Kaisha Hazel
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - George Pottanat
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Sevil Yasar
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Paul Rosenberg
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Marilyn Albert
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Hanzhang Lu
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
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42
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Breiding PS, Kellner-Weldon F, Grunder L, Scutelnic A, Fischer U, Meinel TR, Slavova N, Gralla J, El-Koussy M, Denier N. Quantification of cerebral veins in patients with acute migraine with aura: A fully automated quantification algorithm using susceptibility-weighted imaging. PLoS One 2020; 15:e0233992. [PMID: 32492059 PMCID: PMC7269254 DOI: 10.1371/journal.pone.0233992] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Accepted: 05/16/2020] [Indexed: 12/02/2022] Open
Abstract
Introduction Susceptibility weighted imaging (SWI) is a very sensitive technique that often depicts prominent focal veins (PFV) in patients with acute migraine with aura (MwA). Interpretation of visual venous asymmetry (VVA) between brain hemispheres on SWI may help support the clinical diagnosis of MwA. Our goal was to develop an automated algorithm for segmentation and quantification of cerebral veins using SWI. Materials and methods Expert readers visually evaluated SWI of patients with acute MwA for VVA. Subsequently a fully automated algorithm based on 3D normalization and 2D imaging processing using SPM and MATLAB image processing software including top-hat transform was used to quantify cerebral veins and to calculate volumetric differences between hemispheres. Results Fifty patients with MwA were examined with SWI. VVA was present in 20 of 50 patients (40%). In 95% of patients with VVA, the fully automated calculation agreed with the side that visually harboured more PFV. Our algorithm showed a sensitivity of 95%, specificity of 90% and accuracy of 92% for detecting VVA. Patients with VVA had significantly larger vein volume on the hemisphere with more PFV compared to patients without (15.90 ± 5.38 ml vs 11.93 ± 5.31 ml; p = 0.013). The mean difference in venous volume between hemispheres in patients with VVA was larger compared to patients without VVA (16.34 ± 7.76% vs 4.31 ± 3.26% p < 1E-10). The average time between aura onset and SWI correlated negatively with venous volume of the dominant brain hemisphere (r = -0.348; p = 0.038). Conclusion A fully automated algorithm can accurately identify and quantify cerebral venous distribution on SWI. Absolute quantification may be useful for the future assessment of patients with suspected diseases, which may be associated with a unilateral abnormal degree of venous oxygenation.
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Affiliation(s)
- Philipe Sebastian Breiding
- Institute of Diagnostic and Interventional Radiology, Cantonal Hospital Frauenfeld, Spital Thurgau AG, Frauenfeld, Switzerland
- * E-mail:
| | - Frauke Kellner-Weldon
- Institute of Diagnostic and Interventional Radiology, Cantonal Hospital Luzern, Luzern, Switzerland
- Support Center for Advanced Neuroimaging (SCAN), University Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Inselspital, Bern, Switzerland
| | - Lorenz Grunder
- University Institute of Diagnostic and Interventional Radiology, University of Bern, Inselspital, Bern, Switzerland
| | - Adrian Scutelnic
- Department of Neurology, University of Bern, Inselspital, Bern, Switzerland
| | - Urs Fischer
- Department of Neurology, University of Bern, Inselspital, Bern, Switzerland
| | | | - Nedelina Slavova
- Support Center for Advanced Neuroimaging (SCAN), University Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Inselspital, Bern, Switzerland
- University Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Inselspital, Bern, Switzerland
| | - Jan Gralla
- University Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Inselspital, Bern, Switzerland
| | - Marwan El-Koussy
- Support Center for Advanced Neuroimaging (SCAN), University Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Inselspital, Bern, Switzerland
- University Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Inselspital, Bern, Switzerland
| | - Niklaus Denier
- Support Center for Advanced Neuroimaging (SCAN), University Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Inselspital, Bern, Switzerland
- Department of Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland
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43
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Krishnamurthy V, Krishnamurthy LC, Drucker JH, Kundu S, Ji B, Hortman K, Roberts SR, Mammino K, Tran SM, Gopinath K, McGregor KM, Rodriguez AD, Qiu D, Crosson B, Nocera JR. Correcting Task fMRI Signals for Variability in Baseline CBF Improves BOLD-Behavior Relationships: A Feasibility Study in an Aging Model. Front Neurosci 2020; 14:336. [PMID: 32425745 PMCID: PMC7205008 DOI: 10.3389/fnins.2020.00336] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 03/20/2020] [Indexed: 12/24/2022] Open
Abstract
Blood Oxygen Level Dependent (BOLD) functional MRI is a complex neurovascular signal whose magnitude depends on baseline physiological factors such as cerebral blood flow (CBF). Because baseline CBF varies across the brain and is altered with aging, the interpretation of stand-alone aging-related BOLD changes can be misleading. The primary objective of this study was to develop a methodology that combines task fMRI and arterial spin labeling (ASL) techniques to sensitize task-induced BOLD activity by covarying out the baseline physiology (i.e., CBF) in an aging model. We recruited 11 younger and 13 older healthy participants who underwent ASL and an overt language fMRI task (semantic category member generation). We measured in-scanner language performance to investigate the effect of BOLD sensitization on BOLD-behavior relationships. The results demonstrate that our correction approach is effective at enhancing the specificity and sensitivity of the BOLD signal in both groups. In addition, the correction strengthens the statistical association between task BOLD activity and behavioral performance. Although CBF has inherent age dependence, our results show that retaining the age factor within CBF aides in greater sensitization of task fMRI signals. From a cognitive standpoint, compared to young adults, the older participants showed a delayed domain-general language-related task activity possibly due to compromised vessel compliance. Further, assessment of functional evolution of corrected BOLD activity revealed biphasic BOLD dynamics in both groups where BOLD deactivation may reflect greater semantic demand or increased premium on domain general executive functioning in response to task difficulty. Although it was promising to note that the predictability of behavior using the proposed methodology outperforms other methodologies (i.e., no correction and normalization by division), and provides moderate stability and adequate power, further work with a larger cohort and other task designs is necessary to improve the stability of predicting associated behavior. In summary, we recommend correction of task fMRI signals by covarying out baseline CBF especially when comparing groups with different neurovascular properties. Given that ASL and BOLD fMRI are well established and widely employed techniques, our proposed multi-modal methodology can be readily implemented into data processing pipelines to obtain more accurate BOLD activation maps.
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Affiliation(s)
- Venkatagiri Krishnamurthy
- Department of Neurology, Emory University, Atlanta, GA, United States.,Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center (VAMC), Decatur, GA, United States
| | - Lisa C Krishnamurthy
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center (VAMC), Decatur, GA, United States.,Department of Physics and Astronomy, Georgia State University, Atlanta, GA, United States
| | - Jonathan H Drucker
- Department of Neurology, Emory University, Atlanta, GA, United States.,Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center (VAMC), Decatur, GA, United States
| | - Suprateek Kundu
- Department of Biostatistics and Bioinformatics, Emory University, Atlanta, GA, United States
| | - Bing Ji
- Department of Neurology, Emory University, Atlanta, GA, United States.,Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center (VAMC), Decatur, GA, United States.,Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, United States
| | - Kyle Hortman
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center (VAMC), Decatur, GA, United States
| | - Simone R Roberts
- Department of Neurology, Emory University, Atlanta, GA, United States.,Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center (VAMC), Decatur, GA, United States.,Department of Psychology, Georgia State University, Atlanta, GA, United States
| | - Kevin Mammino
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center (VAMC), Decatur, GA, United States
| | - Stella M Tran
- Department of Psychology, Georgia State University, Atlanta, GA, United States
| | - Kaundinya Gopinath
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, United States
| | - Keith M McGregor
- Department of Neurology, Emory University, Atlanta, GA, United States.,Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center (VAMC), Decatur, GA, United States
| | - Amy D Rodriguez
- Department of Neurology, Emory University, Atlanta, GA, United States.,Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center (VAMC), Decatur, GA, United States
| | - Deqiang Qiu
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, United States
| | - Bruce Crosson
- Department of Neurology, Emory University, Atlanta, GA, United States.,Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center (VAMC), Decatur, GA, United States.,Department of Psychology, Georgia State University, Atlanta, GA, United States
| | - Joe R Nocera
- Department of Neurology, Emory University, Atlanta, GA, United States.,Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center (VAMC), Decatur, GA, United States.,Division of Physical Therapy, School of Medicine, Emory University, Atlanta, GA, United States
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44
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Foster C, Steventon JJ, Helme D, Tomassini V, Wise RG. Assessment of the Effects of Aerobic Fitness on Cerebrovascular Function in Young Adults Using Multiple Inversion Time Arterial Spin Labeling MRI. Front Physiol 2020; 11:360. [PMID: 32372976 PMCID: PMC7187806 DOI: 10.3389/fphys.2020.00360] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 03/27/2020] [Indexed: 11/13/2022] Open
Abstract
This cross-sectional study investigated the effects of aerobic fitness on cerebrovascular function in the healthy brain. Gray matter cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) were quantified in a sample of young adults within a normal fitness range. Based on existing Transcranial Doppler ultrasound and fMRI evidence, we predicted a positive relationship between fitness and resting gray matter CBF and CVR. Exploratory hypotheses that higher V . O2peak would be associated with higher GM volume and cognitive performance were also investigated. 20 adults underwent a V . O2peak test and a battery of cognitive tests. All subjects also underwent an MRI scan where multiple inversion time (MTI) pulsed arterial spin labeling (PASL) was used to quantify resting CBF and CVR to 5% CO2. Region of interest analysis showed a non-significant inverse correlation between whole-brain gray matter CBF and V . O2peak; r = -0.4, p = 0.08, corrected p (p') = 0.16 and a significant positive correlation between V . O2peak and whole-brain averaged gray matter CVR; r = 0.62, p = 0.003, p' = 0.006. Voxel-wise analysis revealed a significant inverse association between V . O2peak and resting CBF in the left and right thalamus, brainstem, right lateral occipital cortex, left intra-calcarine cortex and cerebellum. The results of this study suggest that aerobic fitness is associated with lower baseline CBF and greater CVR in young adults.
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Affiliation(s)
- Catherine Foster
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom
| | - Jessica J. Steventon
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Physics and Astronomy, Cardiff University, Cardiff, United Kingdom
- Neuroscience and Mental Health Research Institute (NMHRI), School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Daniel Helme
- Department of Anaesthetics and Intensive Care Medicine, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Valentina Tomassini
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom
- Division of Psychological Medicine and Clinical Neurosciences, School of Medicine, Cardiff University, Cardiff, United Kingdom
- Department of Neuroscience, Imaging and Clinical Sciences, “G. D’Annunzio University” of Chieti-Pescara, Chieti, Italy
- Institute for Advanced Biomedical Technologies (ITAB), “G. D’Annunzio University” of Chieti-Pescara, Chieti, Italy
| | - Richard G. Wise
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom
- Department of Neuroscience, Imaging and Clinical Sciences, “G. D’Annunzio University” of Chieti-Pescara, Chieti, Italy
- Institute for Advanced Biomedical Technologies (ITAB), “G. D’Annunzio University” of Chieti-Pescara, Chieti, Italy
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45
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Václavů L, Petr J, Petersen ET, Mutsaerts HJ, Majoie CB, Wood JC, VanBavel E, Nederveen AJ, Biemond BJ. Cerebral oxygen metabolism in adults with sickle cell disease. Am J Hematol 2020; 95:401-412. [PMID: 31919876 PMCID: PMC7155077 DOI: 10.1002/ajh.25727] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/02/2020] [Accepted: 01/03/2020] [Indexed: 02/01/2023]
Abstract
In sickle cell disease (SCD), oxygen delivery is impaired due to anemia, especially during times of increased metabolic demand, and cerebral blood flow (CBF) must increase to meet changing physiologic needs. But hyperemia limits cerebrovascular reserve (CVR) and ischemic risk prevails despite elevated CBF. The cerebral metabolic rate of oxygen (CMRO2 ) directly reflects oxygen supply and consumption and may therefore be more insightful than flow-based CVR measures for ischemic risk in SCD. We hypothesized that adults with SCD have impaired CMRO2 at rest and that a vasodilatory challenge with acetazolamide would improve CMRO2 . CMRO2 was calculated from CBF and oxygen extraction fraction (OEF), measured with arterial spin labeling and T2 -prepared tissue relaxation with inversion recovery (T2 -TRIR) MRI. We studied 36 adults with SCD without a clinical history of overt stroke, and nine healthy controls. As expected, CBF was higher in patients with SCD versus controls (mean ± SD: 74 ± 16 versus 46 ± 5 mL/100 g/min, P < .001), resulting in similar oxygen delivery (SCD: 377 ± 67 versus controls: 368 ± 42 μmol O2 /100g/min, P = .69). OEF was lower in patients versus controls (27 ± 4 versus 35 ± 4%, P < .001), resulting in lower CMRO2 in patients versus controls (102 ± 24 versus 127 ± 20 μmol O2 /100g/min, P = .002). After acetazolamide, CMRO2 declined further in patients (P < .01) and did not decline significantly in controls (P = .78), indicating that forcing higher CBF worsened oxygen utilization in SCD patients. This lower CMRO2 could reflect variation between healthy and unhealthy vascular beds in terms of dilatory capacity and resistance whereby dysfunctional vessels become more oxygen-deprived, hence increasing the risk of localized ischemia.
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Affiliation(s)
- Lena Václavů
- Radiology & Nuclear Medicine, Amsterdam UMC University of Amsterdam Amsterdam The Netherlands
- C.J. Gorter Center for High Field MRI, Department of Radiology Leiden University Medical Center, Leiden University Leiden The Netherlands
| | - Jan Petr
- Helmholtz‐Zentrum Dresden‐Rossendorf Institute of Radiopharmaceutical Cancer Research Dresden Germany
| | - Esben Thade Petersen
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research Copenhagen University Hospital Hvidovre Hvidovre Denmark
- Center for Magnetic Resonance, Department of Health Technology Technical University of Denmark Kongens Lyngby Denmark
| | - Henri J.M.M. Mutsaerts
- Radiology & Nuclear Medicine, Amsterdam UMC Vrije Universiteit Amsterdam The Netherlands
| | - Charles B.L. Majoie
- Radiology & Nuclear Medicine, Amsterdam UMC University of Amsterdam Amsterdam The Netherlands
| | - John C. Wood
- Cardiology & Radiology Children's Hospital of Los Angeles Los Angeles California
| | - Ed VanBavel
- Biomedical Engineering & Physics, Amsterdam UMC University of Amsterdam Amsterdam The Netherlands
| | - Aart J. Nederveen
- Radiology & Nuclear Medicine, Amsterdam UMC University of Amsterdam Amsterdam The Netherlands
| | - Bart J. Biemond
- Hematology, Amsterdam UMC University of Amsterdam Amsterdam The Netherlands
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46
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Meijboom R, Steketee RME, Jiskoot LC, Bron EE, van der Lugt A, van Swieten JC, Smits M. Qualitative Assessment of Longitudinal Changes in Phenocopy Frontotemporal Dementia. Front Neurol 2019; 10:1207. [PMID: 31798526 PMCID: PMC6874122 DOI: 10.3389/fneur.2019.01207] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 10/29/2019] [Indexed: 01/22/2023] Open
Abstract
Phenocopy frontotemporal dementia (phFTD) shares core characteristics with behavioral variant frontotemporal dementia (bvFTD), yet without associated cognitive deficits and brain abnormalities on conventional magnetic resonance imaging (MRI), and without progression. Using advanced MRI techniques, we previously observed subtle structural and functional brain changes in phFTD similar to bvFTD. The aim of the current study was to follow these as well as cognition in phFTD over time, by means of a descriptive case series. Cognition, gray matter (GM) volume and white matter (WM) microstructure, and perfusion of 6 phFTD patients were qualitatively compared longitudinally (3-years follow-up), and cross-sectionally with baseline data from 9 bvFTD patients and 17 controls. For functional brain changes, arterial spin labeling (ASL) was performed to assess GM perfusion. For structural brain changes, diffusion tensor imaging was performed to assess WM microstructure and T1w imaging to assess GM volume. MRI acquisition was performed at 3T (General Electric, US). Clinical profiles of phFTD cases at follow-up are described. At follow-up phFTD patients showed clinical symptomatology similar to bvFTD, but had a relatively stable clinical profile. Longitudinal qualitative comparisons in phFTD showed some deterioration of language and memory function, a stable pattern of structural brain abnormalities and increased perfusion over time. Additionally, both baseline and follow-up cognitive scores and structural values in phFTD were generally in between those of controls and bvFTD. Although a descriptive case series does not allow for strong conclusions, these observations in a unique longitudinal phFTD patient cohort are suggestive of the notion that phFTD and bvFTD may belong to the same disease spectrum. They may also provide a basis for further longitudinal studies in phFTD, specifically exploring the structural vs. functional brain changes. Such studies are essential for improved insight, accurate diagnosis, and appropriate treatment of phFTD.
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Affiliation(s)
- Rozanna Meijboom
- Department of Radiology and Nuclear Medicine, Erasmus MC-University Medical Center Rotterdam, Rotterdam, Netherlands.,Center for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Rebecca M E Steketee
- Department of Radiology and Nuclear Medicine, Erasmus MC-University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Lize C Jiskoot
- Department of Neurology, Erasmus MC-University Medical Center Rotterdam, Rotterdam, Netherlands.,Department of Radiology, Leiden University Medical Center, Leiden, Netherlands
| | - Esther E Bron
- Biomedical Imaging Group Rotterdam, Departments of Medical Informatics and Radiology, Erasmus MC-University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Aad van der Lugt
- Department of Radiology and Nuclear Medicine, Erasmus MC-University Medical Center Rotterdam, Rotterdam, Netherlands
| | - John C van Swieten
- Department of Neurology, Erasmus MC-University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Marion Smits
- Department of Radiology and Nuclear Medicine, Erasmus MC-University Medical Center Rotterdam, Rotterdam, Netherlands
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Li W, Xu X, Liu P, Strouse JJ, Casella JF, Lu H, van Zijl PCM, Qin Q. Quantification of whole-brain oxygenation extraction fraction and cerebral metabolic rate of oxygen consumption in adults with sickle cell anemia using individual T 2 -based oxygenation calibrations. Magn Reson Med 2019; 83:1066-1080. [PMID: 31483528 DOI: 10.1002/mrm.27972] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 07/18/2019] [Accepted: 08/05/2019] [Indexed: 12/23/2022]
Abstract
PURPOSE To evaluate different T2 -oxygenation calibrations for estimating venous oxygenation in people with sickle cell anemia (SCA). METHODS Blood T2 values were measured at 3 T in the internal jugular veins of 12 healthy volunteers and 11 SCA participants with no history of stroke, recent transfusion, or renal impairment. T2 -oxygenation relationships of both sickled and normal blood samples were calibrated individually and compared with values generated from published models. After converting venous T2 values to venous oxygenation, whole-brain oxygen extraction fraction and cerebral metabolic rate of oxygen were calculated. RESULTS Sickle blood samples' oxygenation values calculated from our individual calibrations agreed well with measurements using a blood analyzer, whereas previous T2 calibrations based on normal blood samples showed 13%-19% underestimation. Meanwhile, oxygenation values calculated from previous grouped T2 calibration for sickle blood agreed well with experimental measurement on averaged values, but showed up to 20% variation for several individual samples. Using individual T2 calibrations, the whole-brain oxygen extraction fraction and cerebral metabolic rate of oxygen of SCA participants were 0.38 ± 0.08 and 172 ± 42 µmol/min/100 g, respectively, which were comparable to those values measured on healthy volunteers. CONCLUSION Our results confirm that sickle blood T2 values not only depend on the hematocrit and oxygenation values, but also on other hematological factors. The individual T2 calibrations minimized the effect of heterogeneity of sickle blood between different SCA populations and improved the accuracy of T2 -based oximetry. The measured oxygen extraction fraction and cerebral metabolic rate of oxygen of this group of SCA participants were found to not differ significantly from those of healthy individuals.
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Affiliation(s)
- Wenbo Li
- Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - Xiang Xu
- Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - Peiying Liu
- Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - John J Strouse
- Department of Pediatrics, Division of Pediatric Hematology, Johns Hopkins University School of Medicine, Baltimore, Maryland.,Division of Hematology, Duke University, Durham, North Carolina
| | - James F Casella
- Department of Pediatrics, Division of Pediatric Hematology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Hanzhang Lu
- Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Peter C M van Zijl
- Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - Qin Qin
- Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
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Champagne AA, Coverdale NS, Germuska M, Cook DJ. Multi-parametric analysis reveals metabolic and vascular effects driving differences in BOLD-based cerebrovascular reactivity associated with a history of sport concussion. Brain Inj 2019; 33:1479-1489. [PMID: 31354054 PMCID: PMC7115911 DOI: 10.1080/02699052.2019.1644375] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 07/12/2019] [Indexed: 12/19/2022]
Abstract
Objective: Identify alterations in cerebrovascular reactivity (CVR) based on the history of sport-related concussion (SRC). Further explore possible mechanisms underlying differences in vascular physiology using hemodynamic parameters modeled using calibrated magnetic resonance imaging (MRI). Method: End-tidal targeting and dual-echo MRI were combined to probe hypercapnic and hyperoxic challenges in athletes with (n = 32) and without (n = 31) a history of SRC. Concurrent blood oxygenation level dependent (BOLD) and arterial spin labeling (ASL) data were used to compute BOLD-CVR, ASL-CVR, and other physiological parameters including resting oxygen extraction fraction (OEF0) and cerebral blood volume (CBV0). Multiple linear and logistic regressions were then used to identify dominant parameters driving group-differences in BOLD-CVR. Results: Robust evidence for elevated BOLD-CVR were found in athletes with SRC history spreading over parts of the cortical hemispheres. Follow-up analyses showed co-localized differences in ASL-CVR (representing modulation of cerebral blood flow) and hemodynamic factors representing static vascular (i.e., CBV0) and metabolic (i.e., OEF0) effects suggesting that group-based differences in BOLD-CVR may be driven by a mixed effect from factors with vascular and metabolic origins. Conclusion: These results emphasize that while BOLD-CVR offers promises as a surrogate non-specific biomarker for cerebrovascular health following SRC, multiple hemodynamic parameters can affect its relative measurements. Abbreviations: [dHb]: concentration of deoxyhemoglobin; AFNI: Analysis of Functional NeuroImages ( https://afni.nimh.nih.gov ); ASL: arterial spin labeling; BIG: position group: defensive and offensive linemen; BIG-SKILL: position group: full backs, linebackers, running backs, tight-ends; BOLD: blood oxygen level dependent; CBF: cerebral blood flow; CMRO2: cerebral metabolic rate of oxygen consumption; CTL: group of control subjects; CVR: cerebrovascular reactivity; fMRI: functional magnetic resonance imaging; FSL: FMRIB software library ( https://fsl.fmrib.ox.ac.uk/fsl/fslwiki/ ); HC: hypercapnia; HO: hyperoxia; HX: group with history of concussion; M: maximal theoretical BOLD signal upon complete removal of venous dHb; pCASL: pseudo-continuous arterial spin labeling; PETCO2: end-tidal carbon dioxide; PETO2: end-tidal oxygen; SCAT: sport-concussion assessment tool; SKILL: position group: defensive backs, kickers, quarterbacks, safeties, wide-receivers; SRC: sport-related concussion.
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Affiliation(s)
- Allen A. Champagne
- Centre for Neuroscience Studies, Queen’s University, Kingston, ON, Canada
| | | | - Michael Germuska
- Cardiff University Brain Research Imaging Center, Cardiff University, Cardiff, United Kingdom
| | - Douglas J. Cook
- Centre for Neuroscience Studies, Queen’s University, Kingston, ON, Canada
- Department of Surgery, Queen’s University, Kingston, ON, Canada
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49
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McKetton L, Cohn M, Tang-Wai DF, Sobczyk O, Duffin J, Holmes KR, Poublanc J, Sam K, Crawley AP, Venkatraghavan L, Fisher JA, Mikulis DJ. Cerebrovascular Resistance in Healthy Aging and Mild Cognitive Impairment. Front Aging Neurosci 2019; 11:79. [PMID: 31031616 PMCID: PMC6474328 DOI: 10.3389/fnagi.2019.00079] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 03/19/2019] [Indexed: 12/04/2022] Open
Abstract
Measures of cerebrovascular reactivity (CVR) are used to judge the health of the brain vasculature. In this study, we report the use of several different analyses of blood oxygen dependent (BOLD) fMRI responses to CO2 to provide a number of metrics of CVR based on the sigmoidal resistance response to CO2. To assess possible differences in these metrics with age, we compiled atlases reflecting voxel-wise means and standard deviations for four different age ranges and for a group of patients with mild cognitive impairment (MCI) and compared them. Sixty-seven subjects were recruited for this study and scanned at 3T field strength. Of those, 51 healthy control volunteers between the ages of 18–83 were recruited, and 16 (MCI) subjects between the ages of 61–83 were recruited. Testing was carried out using an automated computer-controlled gas blender to induce hypercapnia in a step and ramp paradigm while monitoring end-tidal partial pressures of CO2. Surprisingly, some resistance sigmoid parameters in the oldest control group were increased compared to the youngest control group. Resistance amplitude maps showed increases in clusters within the temporal cortex, thalamus, corpus callosum and brainstem, and resistance reserve maps showed increases in clusters within the cingulate cortex, frontal gyrus, and corpus callosum. These findings suggest that some aspects of vascular reactivity in parts of the brain are initially maintained with age but then may increase in later years. We found significant reductions in all resistance sigmoid parameters (amplitude, reserve, sensitivity, midpoint, and range) when comparing MCI patients to controls. Additionally, in controls and in MCI patients, amplitude, range, reserve, and sensitivity in white matter (WM) was significantly reduced compared to gray matter (GM). WM midpoints were significantly above those of GM. Our general conclusion is that vascular regulation in terms of cerebral blood flow (CBF) responsiveness to CO2 is not significantly affected by age, but is reduced in MCI. These changes in cerebrovascular regulation demonstrate the value of resistance metrics for mapping areas of dysregulated blood flow in individuals with MCI. They may also be of value in the investigation of patients with vascular risk factors at risk for developing vascular dementia.
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Affiliation(s)
- Larissa McKetton
- Joint Department of Medical Imaging, University Health Network (UHN), Toronto, ON, Canada
| | - Melanie Cohn
- Krembil Brain Institute, University Health Network (UHN), Toronto, ON, Canada.,Department of Psychology, University of Toronto, Toronto, ON, Canada
| | - David F Tang-Wai
- Krembil Brain Institute, University Health Network (UHN), Toronto, ON, Canada.,Department of Medicine, Division of Neurology, University of Toronto and the University Health Network Memory Clinic, Toronto, ON, Canada
| | - Olivia Sobczyk
- Joint Department of Medical Imaging, University Health Network (UHN), Toronto, ON, Canada
| | - James Duffin
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Kenneth R Holmes
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Julien Poublanc
- Joint Department of Medical Imaging, University Health Network (UHN), Toronto, ON, Canada
| | - Kevin Sam
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Adrian P Crawley
- Joint Department of Medical Imaging, University Health Network (UHN), Toronto, ON, Canada
| | - Lashmi Venkatraghavan
- Department of Anaesthesia and Pain Management, University Health Network (UHN), Toronto, ON, Canada
| | - Joseph A Fisher
- Joint Department of Medical Imaging, University Health Network (UHN), Toronto, ON, Canada.,Institute of Medical Science, University of Toronto, Toronto, ON, Canada.,Department of Anaesthesia and Pain Management, University Health Network (UHN), Toronto, ON, Canada
| | - David J Mikulis
- Joint Department of Medical Imaging, University Health Network (UHN), Toronto, ON, Canada.,Krembil Brain Institute, University Health Network (UHN), Toronto, ON, Canada.,Institute of Medical Science, University of Toronto, Toronto, ON, Canada
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Ruotsalainen I, Renvall V, Gorbach T, Syväoja HJ, Tammelin TH, Karvanen J, Parviainen T. Aerobic fitness, but not physical activity, is associated with grey matter volume in adolescents. Behav Brain Res 2019; 362:122-130. [DOI: 10.1016/j.bbr.2018.12.041] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 11/28/2018] [Accepted: 12/20/2018] [Indexed: 12/22/2022]
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