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Ahmed S, Saini J, Gorantla P, Kulanthaivelu K, Shashidhar A, Deora H, Holla VV, Arora A. An Illustrative Review of the Pathomechanisms of Symptomatic Developmental Venous Anomalies. J Comput Assist Tomogr 2023; 47:940-950. [PMID: 37948370 DOI: 10.1097/rct.0000000000001508] [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: 07/23/2023]
Abstract
OBJECTIVE Symptomatic developmental venous anomalies (DVAs) are rare. Here, we illustrate the varied clinicoradiologic profiles of symptomatic DVAs and contemplate the mechanisms that render these (allegedly) benign entities symptomatic supported by a review of literature. METHODS Institutional databases were searched to identify cases of symptomatic DVAs. Clinical and imaging (angiographic and cross-sectional) data of 9 cases with 11 neurovascular symptoms consequent to inflow/outflow perturbations and mechanical obstruction that manifested because of the strategic topography of underlying DVAs were analyzed. A review of the existing literature on DVAs in agreement with our case series was performed on publications retrieved from the PubMed database. RESULTS Symptoms secondary to venous hypertension arising from flow-related perturbations were broadly divided into those arising from restricted outflow and increased inflow. Restricted outflow occurred because of collector vein stenosis (n = 2) and collector vein/DVA thrombosis (n = 3), whereas the latter pathomechanism was initiated by arterialized/transitional DVAs (n = 2). A mechanical/obstructive pathomechanism culminating in moderate supratentorial ventriculomegaly was noted in 1 case. One patient was given a diagnosis of hemorrhage associated with a cavernoma. CONCLUSIONS Awareness and contextualization of potential flow-related perturbations and mechanical insults that render DVAs symptomatic aid in accurate diagnosis, management, and prognostication.
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Affiliation(s)
- Sabha Ahmed
- From the Departments of Neuroimaging and Interventional Radiology
| | - Jitender Saini
- From the Departments of Neuroimaging and Interventional Radiology
| | | | | | - Abhinith Shashidhar
- Neurosurgery, National Institute of Mental Health and Neurosciences, Bengaluru, Karnataka, India
| | - Harsh Deora
- Neurosurgery, National Institute of Mental Health and Neurosciences, Bengaluru, Karnataka, India
| | - Vikram V Holla
- Neurosurgery, National Institute of Mental Health and Neurosciences, Bengaluru, Karnataka, India
| | - Ankit Arora
- From the Departments of Neuroimaging and Interventional Radiology
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2
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Guetarni Z, Bernard R, Boulouis G, Labeyrie MA, Biondi A, Velasco S, Saliou G, Bartolini B, Daumas-Duport B, Bourcier R, Janot K, Herbreteau D, Michelozzi C, Premat K, Redjem H, Escalard S, Bricout N, Thouant P, Arteaga C, Pierot L, Tahon F, Boubagra K, Ikka L, Chabert E, Lenck S, Guédon A, Consoli A, Saleme S, Forestier G, Di Maria F, Ferré JC, Anxionnat R, Eugene F, Kerleroux B, Dargazanli C, Sourour NA, Clarençon F, Shotar E. Longitudinal radiological follow-up of individual level non-ischemic cerebral enhancing lesions following endovascular aneurysm treatment. J Neurointerv Surg 2023:jnis-2023-020060. [PMID: 37770183 DOI: 10.1136/jnis-2023-020060] [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: 03/05/2023] [Accepted: 07/07/2023] [Indexed: 10/03/2023]
Abstract
BACKGROUND Non-ischemic cerebral enhancing (NICE) lesions following aneurysm endovascular therapy are exceptionally rare, with unknown longitudinal evolution. OBJECTIVE To evaluate the radiological behavior of individual NICE lesions over time. METHODS Patients included in a retrospective national multicentric inception cohort were analyzed. NICE lesions were defined, using MRI, as delayed onset punctate, nodular, or annular foci enhancements with peri-lesion edema, distributed in the vascular territory of the aneurysm treatment, with no other confounding disease. Lesion burden and the longitudinal behavior of individual lesions were assessed. RESULTS Twenty-two patients were included, with a median initial lesion burden of 36 (IQR 17-54) on the first MRI scan. Of the 22 patients with at least one follow-up MRI scan, 16 (73%) had new lesions occurring mainly within the first 200 weeks after the date of the procedure. The median number of new lesions per MRI was 6 (IQR 2-16). Among the same 22 patients, 7 (32%) had recurrent lesions. The median persistent enhancement of a NICE lesion was 13 weeks (IQR 6-30). No factor was predictive of early regression of enhancement activity with lesion regression kinetics mainly being patient-dependent. CONCLUSIONS The behavior of individual NICE lesions was found to be highly variable with an overall patient-dependent regression velocity.
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Affiliation(s)
- Zakaria Guetarni
- Department of Interventional Neuroradiology, Pitié-Salpêtrière Hospital, Paris, France
| | - Remy Bernard
- Department of Neurosurgical Anesthesiology and Intensive Care, Pitié-Salpêtrière Hospital, Paris, France
| | - Grégoire Boulouis
- Department of Interventional Neuroradiology, CHU de Tours, Tours, France
| | | | - Alessandra Biondi
- Department of Interventional Neuroradiology, Besançon University Hospital, Besancon, France
| | - Stéphane Velasco
- Department of Interventional Neuroradiology, CHU de Poitiers, Poitiers, France
| | - Guillaume Saliou
- Department of Diagnostic and Interventional Radiology, Centre Hospitalier Universitaire Vaudois, Lausanne, Vaud, Switzerland
| | - Bruno Bartolini
- Department of Diagnostic and Interventional Radiology, Centre Hospitalier Universitaire Vaudois, Lausanne, Vaud, Switzerland
| | - Benjamin Daumas-Duport
- Department of Interventional Neuroradiology, University Hospital of Nantes, Nantes, France
| | - Romain Bourcier
- Department of Interventional Neuroradiology, University Hospital of Nantes, Nantes, France
| | - Kevin Janot
- Department of Interventional Neuroradiology, CHU de Tours, Tours, France
| | - Denis Herbreteau
- Department of Interventional Neuroradiology, CHU de Tours, Tours, France
| | - Caterina Michelozzi
- Department of Interventional Neuroradiology, Michallon Hospital, La Tronche, France
| | - Kevin Premat
- Department of Interventional Neuroradiology, Pitié-Salpêtrière Hospital, Paris, France
| | - Hocine Redjem
- Department of Interventional Neuroradiology, Fondation Rothschild Hospital, Paris, France
| | - Simon Escalard
- Department of Interventional Neuroradiology, Fondation Rothschild Hospital, Paris, France
| | - Nicolas Bricout
- Department of interventional Neuroradiology, Centre Hospitalier Universitaire de Lille, Lille, France
| | - Pierre Thouant
- Department of Neuroradiology, F Mitterand Hospital, Dijon, France
| | - Charles Arteaga
- Radiology Department, Hôpital d'Instruction des Armées Sainte-Anne Bibliothèque, Toulon, Provence-Alpes-Côte d'Azu, France
| | - Laurent Pierot
- Department of Interventional Neuroradiology, University Hospital Reims, Reims, France
| | - Florence Tahon
- Department of Neuroradiology, Grenoble Alpes University Hospital, Grenoble, France
| | - Kamel Boubagra
- Department of Neuroradiology, Grenoble Alpes University Hospital, Grenoble, France
| | - Leon Ikka
- Department of Interventional Neuroradiology, Bicetre Hospital, Le Kremlin Bicetre, France
| | - Emmanuel Chabert
- Department of Neuroradiology, Centre Hospitalier Universitaire de Clermont-Ferrand, Clermont-Ferrand, France
| | - Stephanie Lenck
- Department of Interventional Neuroradiology, Pitié-Salpêtrière Hospital, Paris, France
| | - Alexis Guédon
- Department of Interventional Neuroradiology, Hopital Lariboisiere, Paris, France
| | - Arturo Consoli
- Diagnostic and Therapeutic Neuroradiology Department, Hopital Foch, Suresnes, Île-de-France, France
| | - Suzana Saleme
- Department of Interventional Neuroradiology, Centre Hospitalier Universitaire de Limoges, Limoges, France
| | - Géraud Forestier
- Department of Interventional Neuroradiology, Centre Hospitalier Universitaire de Limoges, Limoges, France
| | - Federico Di Maria
- Diagnostic and Therapeutic Neuroradiology Department, Hopital Foch, Suresnes, Île-de-France, France
| | | | - René Anxionnat
- Department of Diagnostic and Interventional Neuroradiology, CHRU Nancy, Nancy, Lorraine, France
| | - Francois Eugene
- Department of Neuroradiology, University Hospital of Rennes, Rennes, France
| | - Basile Kerleroux
- Department of Interventional Neuroradiology, Saint Anne Hospital Centre, Paris, France
| | - Cyril Dargazanli
- Department of Neuroradiology, University Hospital Centre Montpellier, Montpellier, Occitanie, France
| | - Nader-Antoine Sourour
- Department of Interventional Neuroradiology, Pitié-Salpêtrière Hospital, Paris, France
| | - Frédéric Clarençon
- Department of Interventional Neuroradiology, Pitié-Salpêtrière Hospital, Paris, France
| | - Eimad Shotar
- Department of Interventional Neuroradiology, Pitié-Salpêtrière Hospital, Paris, France
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3
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Hu Z, Christodoulou AG, Wang N, Xie Y, Shiroishi MS, Yang W, Zada G, Chow FE, Margol AS, Tamrazi B, Chang EL, Li D, Fan Z. MR multitasking-based dynamic imaging for cerebrovascular evaluation (MT-DICE): Simultaneous quantification of permeability and leakage-insensitive perfusion by dynamic T 1 / T 2 * mapping. Magn Reson Med 2023; 89:161-176. [PMID: 36128892 PMCID: PMC9826278 DOI: 10.1002/mrm.29431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 07/16/2022] [Accepted: 08/10/2022] [Indexed: 01/26/2023]
Abstract
PURPOSE To develop an MR multitasking-based dynamic imaging for cerebrovascular evaluation (MT-DICE) technique for simultaneous quantification of permeability and leakage-insensitive perfusion with a single-dose contrast injection. METHODS MT-DICE builds on a saturation-recovery prepared multi-echo fast low-angle shot sequence. The k-space is randomly sampled for 7.6 min, with single-dose contrast agent injected 1.5 min into the scan. MR multitasking is used to model the data into six dimensions, including three spatial dimensions for whole-brain coverage, a saturation-recovery time dimension, and a TE dimension for dynamicT 1 $$ {\mathrm{T}}_1 $$ andT 2 * $$ {\mathrm{T}}_2^{\ast } $$ quantification, respectively, and a contrast dynamics dimension for capturing contrast kinetics. The derived pixel-wiseT 1 / T 2 * $$ {\mathrm{T}}_1/{\mathrm{T}}_2^{\ast } $$ time series are converted into contrast concentration-time curves for calculation of kinetic metrics. The technique was assessed for its agreement with reference methods inT 1 $$ {\mathrm{T}}_1 $$ andT 2 * $$ {\mathrm{T}}_2^{\ast } $$ measurements in eight healthy subjects and, in three of them, inter-session repeatability of permeability and leakage-insensitive perfusion parameters. Its feasibility was also demonstrated in four patients with brain tumors. RESULTS MT-DICET 1 / T 2 * $$ {\mathrm{T}}_1/{\mathrm{T}}_2^{\ast } $$ values of normal gray matter and white matter were in excellent agreement with reference values (intraclass correlation coefficients = 0.860/0.962 for gray matter and 0.925/0.975 for white matter ). Both permeability and perfusion parameters demonstrated good to excellent intersession agreement with the lowest intraclass correlation coefficients at 0.694. Contrast kinetic parameters in all healthy subjects and patients were within the literature range. CONCLUSION Based on dynamicT 1 / T 2 * $$ {\mathrm{T}}_1/{\mathrm{T}}_2^{\ast } $$ mapping, MT-DICE allows for simultaneous quantification of permeability and leakage-insensitive perfusion metrics with a single-dose contrast injection.
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Affiliation(s)
- Zhehao Hu
- Department of RadiologyUniversity of Southern California
Los AngelesCaliforniaUSA
- Biomedical Imaging Research InstituteCedars‐Sinai Medical CenterLos AngelesCaliforniaUSA
- Department of BioengineeringUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - Anthony G. Christodoulou
- Biomedical Imaging Research InstituteCedars‐Sinai Medical CenterLos AngelesCaliforniaUSA
- Department of BioengineeringUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - Nan Wang
- Biomedical Imaging Research InstituteCedars‐Sinai Medical CenterLos AngelesCaliforniaUSA
| | - Yibin Xie
- Biomedical Imaging Research InstituteCedars‐Sinai Medical CenterLos AngelesCaliforniaUSA
| | - Mark S. Shiroishi
- Department of RadiologyUniversity of Southern California
Los AngelesCaliforniaUSA
| | - Wensha Yang
- Department of Radiation OncologyUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Gabriel Zada
- Department of NeurosurgeryUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Frances E. Chow
- Department of NeurosurgeryUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Ashley S. Margol
- Department of Neuro‐oncologyChildren's Hospital Los AngelesLos AngelesCaliforniaUSA
| | - Benita Tamrazi
- Department of RadiologyChildren's Hospital Los AngelesLos AngelesCaliforniaUSA
| | - Eric L. Chang
- Department of Radiation OncologyUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Debiao Li
- Biomedical Imaging Research InstituteCedars‐Sinai Medical CenterLos AngelesCaliforniaUSA
- Department of BioengineeringUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - Zhaoyang Fan
- Department of RadiologyUniversity of Southern California
Los AngelesCaliforniaUSA
- Biomedical Imaging Research InstituteCedars‐Sinai Medical CenterLos AngelesCaliforniaUSA
- Department of Radiation OncologyUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
- Department of Biomedical EngineeringUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
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4
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van Dinther M, Voorter PH, Jansen JF, Jones EA, van Oostenbrugge RJ, Staals J, Backes WH. Assessment of microvascular rarefaction in human brain disorders using physiological magnetic resonance imaging. J Cereb Blood Flow Metab 2022; 42:718-737. [PMID: 35078344 PMCID: PMC9014687 DOI: 10.1177/0271678x221076557] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cerebral microvascular rarefaction, the reduction in number of functional or structural small blood vessels in the brain, is thought to play an important role in the early stages of microvascular related brain disorders. A better understanding of its underlying pathophysiological mechanisms, and methods to measure microvascular density in the human brain are needed to develop biomarkers for early diagnosis and to identify targets for disease modifying treatments. Therefore, we provide an overview of the assumed main pathophysiological processes underlying cerebral microvascular rarefaction and the evidence for rarefaction in several microvascular related brain disorders. A number of advanced physiological MRI techniques can be used to measure the pathological alterations associated with microvascular rarefaction. Although more research is needed to explore and validate these MRI techniques in microvascular rarefaction in brain disorders, they provide a set of promising future tools to assess various features relevant for rarefaction, such as cerebral blood flow and volume, vessel density and radius and blood-brain barrier leakage.
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Affiliation(s)
- Maud van Dinther
- Department of Neurology, Maastricht University Medical Center, The Netherlands.,CARIM - School for Cardiovascular Diseases, Maastricht University, The Netherlands
| | - Paulien Hm Voorter
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, The Netherlands.,MHeNs - School for Mental Health and Neuroscience, Maastricht University, The Netherlands
| | - Jacobus Fa Jansen
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, The Netherlands.,MHeNs - School for Mental Health and Neuroscience, Maastricht University, The Netherlands
| | | | - Robert J van Oostenbrugge
- Department of Neurology, Maastricht University Medical Center, The Netherlands.,CARIM - School for Cardiovascular Diseases, Maastricht University, The Netherlands.,MHeNs - School for Mental Health and Neuroscience, Maastricht University, The Netherlands
| | - Julie Staals
- Department of Neurology, Maastricht University Medical Center, The Netherlands.,CARIM - School for Cardiovascular Diseases, Maastricht University, The Netherlands
| | - Walter H Backes
- CARIM - School for Cardiovascular Diseases, Maastricht University, The Netherlands.,Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, The Netherlands.,MHeNs - School for Mental Health and Neuroscience, Maastricht University, The Netherlands
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5
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Booth TC, Wiegers EC, Warnert EAH, Schmainda KM, Riemer F, Nechifor RE, Keil VC, Hangel G, Figueiredo P, Álvarez-Torres MDM, Henriksen OM. High-Grade Glioma Treatment Response Monitoring Biomarkers: A Position Statement on the Evidence Supporting the Use of Advanced MRI Techniques in the Clinic, and the Latest Bench-to-Bedside Developments. Part 2: Spectroscopy, Chemical Exchange Saturation, Multiparametric Imaging, and Radiomics. Front Oncol 2022; 11:811425. [PMID: 35340697 PMCID: PMC8948428 DOI: 10.3389/fonc.2021.811425] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 12/28/2021] [Indexed: 01/16/2023] Open
Abstract
Objective To summarize evidence for use of advanced MRI techniques as monitoring biomarkers in the clinic, and to highlight the latest bench-to-bedside developments. Methods The current evidence regarding the potential for monitoring biomarkers was reviewed and individual modalities of metabolism and/or chemical composition imaging discussed. Perfusion, permeability, and microstructure imaging were similarly analyzed in Part 1 of this two-part review article and are valuable reading as background to this article. We appraise the clinic readiness of all the individual modalities and consider methodologies involving machine learning (radiomics) and the combination of MRI approaches (multiparametric imaging). Results The biochemical composition of high-grade gliomas is markedly different from healthy brain tissue. Magnetic resonance spectroscopy allows the simultaneous acquisition of an array of metabolic alterations, with choline-based ratios appearing to be consistently discriminatory in treatment response assessment, although challenges remain despite this being a mature technique. Promising directions relate to ultra-high field strengths, 2-hydroxyglutarate analysis, and the use of non-proton nuclei. Labile protons on endogenous proteins can be selectively targeted with chemical exchange saturation transfer to give high resolution images. The body of evidence for clinical application of amide proton transfer imaging has been building for a decade, but more evidence is required to confirm chemical exchange saturation transfer use as a monitoring biomarker. Multiparametric methodologies, including the incorporation of nuclear medicine techniques, combine probes measuring different tumor properties. Although potentially synergistic, the limitations of each individual modality also can be compounded, particularly in the absence of standardization. Machine learning requires large datasets with high-quality annotation; there is currently low-level evidence for monitoring biomarker clinical application. Conclusion Advanced MRI techniques show huge promise in treatment response assessment. The clinical readiness analysis highlights that most monitoring biomarkers require standardized international consensus guidelines, with more facilitation regarding technique implementation and reporting in the clinic.
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Affiliation(s)
- Thomas C. Booth
- School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom
- Department of Neuroradiology, King’s College Hospital NHS Foundation Trust, London, United Kingdom
| | - Evita C. Wiegers
- Department of Radiology, University Medical Center Utrecht, Utrecht, Netherlands
| | | | - Kathleen M. Schmainda
- Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Frank Riemer
- Mohn Medical Imaging and Visualization Centre (MMIV), Department of Radiology, Haukeland University Hospital, Bergen, Norway
| | - Ruben E. Nechifor
- Department of Clinical Psychology and Psychotherapy International Institute for the Advanced Studies of Psychotherapy and Applied Mental Health, Babes-Bolyai University, Cluj-Napoca, Romania
| | - Vera C. Keil
- Department of Radiology and Nuclear Medicine, Amsterdam UMC, location VUmc, Amsterdam, Netherlands
| | - Gilbert Hangel
- Department of Neurosurgery & High-Field MR Centre, Department of Biomedical Imaging and Image-Guided Therapy, Medical University Vienna, Vienna, Austria
| | - Patrícia Figueiredo
- Department of Bioengineering and Institute for Systems and Robotics - Lisboa, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | | | - Otto M. Henriksen
- Department of Clinical Physiology, Nuclear medicine and PET, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
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6
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Eskildsen SF, Iranzo A, Stokholm MG, Stær K, Østergaard K, Serradell M, Otto M, Svendsen KB, Garrido A, Vilas D, Borghammer P, Santamaria J, Møller A, Gaig C, Brooks DJ, Tolosa E, Østergaard L, Pavese N. Impaired cerebral microcirculation in isolated REM sleep behaviour disorder. Brain 2021; 144:1498-1508. [PMID: 33880533 DOI: 10.1093/brain/awab054] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 11/19/2020] [Accepted: 12/09/2020] [Indexed: 01/18/2023] Open
Abstract
During the prodromal period of Parkinson's disease and other α-synucleinopathy-related parkinsonisms, neurodegeneration is thought to progressively affect deep brain nuclei, such as the locus coeruleus, caudal raphe nucleus, substantia nigra, and the forebrain nucleus basalis of Meynert. Besides their involvement in the regulation of mood, sleep, behaviour, and memory functions, these nuclei also innervate parenchymal arterioles and capillaries throughout the cortex, possibly to ensure that oxygen supplies are adjusted according to the needs of neural activity. The aim of this study was to examine whether patients with isolated REM sleep behaviour disorder, a parasomnia considered to be a prodromal phenotype of α-synucleinopathies, reveal microvascular flow disturbances consistent with disrupted central blood flow control. We applied dynamic susceptibility contrast MRI to characterize the microscopic distribution of cerebral blood flow in the cortex of 20 polysomnographic-confirmed patients with isolated REM sleep behaviour disorder (17 males, age range: 54-77 years) and 25 healthy matched controls (25 males, age range: 58-76 years). Patients and controls were cognitively tested by Montreal Cognitive Assessment and Mini Mental State Examination. Results revealed profound hypoperfusion and microvascular flow disturbances throughout the cortex in patients compared to controls. In patients, the microvascular flow disturbances were seen in cortical areas associated with language comprehension, visual processing and recognition and were associated with impaired cognitive performance. We conclude that cortical blood flow abnormalities, possibly related to impaired neurogenic control, are present in patients with isolated REM sleep behaviour disorder and associated with cognitive dysfunction. We hypothesize that pharmacological restoration of perivascular neurotransmitter levels could help maintain cognitive function in patients with this prodromal phenotype of parkinsonism.
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Affiliation(s)
- Simon F Eskildsen
- Center of Functionally Integrative Neuroscience and MINDLab, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Alex Iranzo
- Department of Neurology, Hospital Clínic de Barcelona, Barcelona, Spain
| | - Morten G Stokholm
- Department of Nuclear Medicine & PET Centre, Aarhus University Hospital, Aarhus, Denmark
| | - Kristian Stær
- Department of Nuclear Medicine & PET Centre, Aarhus University Hospital, Aarhus, Denmark
| | - Karen Østergaard
- Department of Neurology, Aarhus University Hospital, Aarhus, Denmark
| | - Mónica Serradell
- Department of Neurology, Hospital Clínic de Barcelona, Barcelona, Spain
| | - Marit Otto
- Department of Clinical Neurophysiology, Aarhus University Hospital, Aarhus, Denmark
| | | | - Alicia Garrido
- Department of Neurology, Hospital Clínic de Barcelona, Barcelona, Spain
| | - Dolores Vilas
- Department of Neurology, Hospital Clínic de Barcelona, Barcelona, Spain
| | - Per Borghammer
- Department of Nuclear Medicine & PET Centre, Aarhus University Hospital, Aarhus, Denmark
| | - Joan Santamaria
- Department of Neurology, Hospital Clínic de Barcelona, Barcelona, Spain
| | - Arne Møller
- Center of Functionally Integrative Neuroscience and MINDLab, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Department of Nuclear Medicine & PET Centre, Aarhus University Hospital, Aarhus, Denmark
| | - Carles Gaig
- Department of Neurology, Hospital Clínic de Barcelona, Barcelona, Spain
| | - David J Brooks
- Department of Nuclear Medicine & PET Centre, Aarhus University Hospital, Aarhus, Denmark.,Translational and Clinical Research Institute, Newcastle University, England, UK
| | - Eduardo Tolosa
- Department of Neurology, Hospital Clínic de Barcelona, Barcelona, Spain.,Parkinson disease and Movement Disorders Unit, Neurology Service, Hospital Clínic de Barcelona, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), University of Barcelona, Barcelona, Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Spain
| | - Leif Østergaard
- Center of Functionally Integrative Neuroscience and MINDLab, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Neuroradiology Research Unit, Department of Radiology, Aarhus University Hospital, Denmark
| | - Nicola Pavese
- Department of Nuclear Medicine & PET Centre, Aarhus University Hospital, Aarhus, Denmark.,Translational and Clinical Research Institute, Newcastle University, England, UK
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7
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Assessment of tumor hypoxia and perfusion in recurrent glioblastoma following bevacizumab failure using MRI and 18F-FMISO PET. Sci Rep 2021; 11:7632. [PMID: 33828310 PMCID: PMC8027395 DOI: 10.1038/s41598-021-84331-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Accepted: 02/03/2021] [Indexed: 01/16/2023] Open
Abstract
Tumoral hypoxia correlates with worse outcomes in glioblastoma (GBM). While bevacizumab is routinely used to treat recurrent GBM, it may exacerbate hypoxia. Evofosfamide is a hypoxia-targeting prodrug being tested for recurrent GBM. To characterize resistance to bevacizumab and identify those with recurrent GBM who may benefit from evofosfamide, we ascertained MRI features and hypoxia in patients with GBM progression receiving both agents. Thirty-three patients with recurrent GBM refractory to bevacizumab were enrolled. Patients underwent MR and 18F-FMISO PET imaging at baseline and 28 days. Tumor volumes were determined, MRI and 18F-FMISO PET-derived parameters calculated, and Spearman correlations between parameters assessed. Progression-free survival decreased significantly with hypoxic volume [hazard ratio (HR) = 1.67, 95% confidence interval (CI) 1.14 to 2.46, P = 0.009] and increased significantly with time to the maximum value of the residue (Tmax) (HR = 0.54, 95% CI 0.34 to 0.88, P = 0.01). Overall survival decreased significantly with hypoxic volume (HR = 1.71, 95% CI 1.12 to 12.61, p = 0.01), standardized relative cerebral blood volume (srCBV) (HR = 1.61, 95% CI 1.09 to 2.38, p = 0.02), and increased significantly with Tmax (HR = 0.31, 95% CI 0.15 to 0.62, p < 0.001). Decreases in hypoxic volume correlated with longer overall and progression-free survival, and increases correlated with shorter overall and progression-free survival. Hypoxic volume and volume ratio were positively correlated (rs = 0.77, P < 0.0001), as were hypoxia volume and T1 enhancing tumor volume (rs = 0.75, P < 0.0001). Hypoxia is a key biomarker in patients with bevacizumab-refractory GBM. Hypoxia and srCBV were inversely correlated with patient outcomes. These radiographic features may be useful in evaluating treatment and guiding treatment considerations.
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8
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Han M, Yang B, Fernandez B, Lafontaine M, Alcaide-Leon P, Jakary A, Burns BL, Morrison MA, Villanueva-Meyer JE, Chang SM, Banerjee S, Lupo JM. Simultaneous multi-slice spin- and gradient-echo dynamic susceptibility-contrast perfusion-weighted MRI of gliomas. NMR IN BIOMEDICINE 2021; 34:e4399. [PMID: 32844496 DOI: 10.1002/nbm.4399] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 08/06/2020] [Accepted: 08/08/2020] [Indexed: 06/11/2023]
Abstract
Although combined spin- and gradient-echo (SAGE) dynamic susceptibility-contrast (DSC) MRI can provide perfusion quantification that is sensitive to both macrovessels and microvessels while correcting for T1 -shortening effects, spatial coverage is often limited in order to maintain a high temporal resolution for DSC quantification. In this work, we combined a SAGE echo-planar imaging (EPI) sequence with simultaneous multi-slice (SMS) excitation and blipped controlled aliasing in parallel imaging (blipped CAIPI) at 3 T to achieve both high temporal resolution and whole brain coverage. Two protocols using this sequence with multi-band (MB) acceleration factors of 2 and 3 were evaluated in 20 patients with treated gliomas to determine the optimal scan parameters for clinical use. ΔR2 *(t) and ΔR2 (t) curves were derived to calculate dynamic signal-to-noise ratio (dSNR), ΔR2 *- and ΔR2 -based relative cerebral blood volume (rCBV), and mean vessel diameter (mVD) for each voxel. The resulting SAGE DSC images acquired using MB acceleration of 3 versus 2 appeared visually similar in terms of image distortion and contrast. The difference in the mean dSNR from normal-appearing white matter (NAWM) and that in the mean dSNR between NAWM and normal-appearing gray matter were not statistically significant between the two protocols. ΔR2 *- and ΔR2 -rCBV maps and mVD maps provided unique contrast and spatial heterogeneity within tumors.
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Affiliation(s)
- Misung Han
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, California, USA
| | - Baolian Yang
- Applications and Workflow, GE Healthcare, Waukesha, Wisconsin, USA
| | | | - Marisa Lafontaine
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, California, USA
| | - Paula Alcaide-Leon
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, California, USA
| | - Angela Jakary
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, California, USA
| | - Brian L Burns
- Applications and Workflow, GE Healthcare, Menlo Park, California, USA
| | - Melanie A Morrison
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, California, USA
| | - Javier E Villanueva-Meyer
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, California, USA
| | - Susan M Chang
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, California, USA
| | | | - Janine M Lupo
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, California, USA
- UCSF-UC Berkeley Graduate Program in Bioengineering, University of California, San Francisco, and University of California, Berkeley, San Francisco, California, USA
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9
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Nielsen RB, Parbo P, Ismail R, Dalby R, Tietze A, Brændgaard H, Gottrup H, Brooks DJ, Østergaard L, Eskildsen SF. Impaired perfusion and capillary dysfunction in prodromal Alzheimer's disease. ALZHEIMER'S & DEMENTIA (AMSTERDAM, NETHERLANDS) 2020; 12:e12032. [PMID: 32490139 PMCID: PMC7241262 DOI: 10.1002/dad2.12032] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 02/21/2020] [Accepted: 02/24/2020] [Indexed: 12/19/2022]
Abstract
INTRODUCTION Cardiovascular disease increases the risk of developing Alzheimer's disease (AD), and growing evidence suggests an involvement of cerebrovascular pathology in AD. Capillary dysfunction, a condition in which capillary flow disturbances rather than arterial blood supply limit brain oxygen extraction, could represent an overlooked vascular contributor to neurodegeneration. We examined whether cortical capillary transit-time heterogeneity (CTH), an index of capillary dysfunction, is elevated in amyloid-positive patients with mild cognitive impairment (prodromal AD [pAD]). METHODS We performed structural and perfusion weighted MRI in 22 pAD patients and 21 healthy controls. RESULTS We found hypoperfusion, reduced blood volume, and elevated CTH in the parietal and frontal cortices of pAD-patients compared to controls, while only the precuneus showed focal cortical atrophy. DISCUSSION We propose that microvascular flow disturbances antedate cortical atrophy and may limit local tissue oxygenation in pAD. We speculate that capillary dysfunction contributes to the development of neurodegeneration in AD.
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Affiliation(s)
- Rune B. Nielsen
- Center of Functionally Integrative NeuroscienceAarhus UniversityAarhusDenmark
| | - Peter Parbo
- Department of Nuclear Medicine and PET CentreAarhus University HospitalAarhusDenmark
| | - Rola Ismail
- Department of Nuclear Medicine and PET CentreAarhus University HospitalAarhusDenmark
| | - Rikke Dalby
- Center of Functionally Integrative NeuroscienceAarhus UniversityAarhusDenmark
- Department of NeuroradiologyAarhus University HospitalAarhusDenmark
| | - Anna Tietze
- Charité, UniversitätsmedizinInstitute of NeuroradiologyBerlinGermany
| | - Hans Brændgaard
- Dementia ClinicDepartment of NeurologyAarhus University HospitalAarhusDenmark
| | - Hanne Gottrup
- Dementia ClinicDepartment of NeurologyAarhus University HospitalAarhusDenmark
| | - David J. Brooks
- Department of Nuclear Medicine and PET CentreAarhus University HospitalAarhusDenmark
- Division of NeuroscienceDepartment of MedicineImperial College LondonLondonUK
- Division of NeuroscienceNewcastle UniversityNewcastle upon TyneUK
| | - Leif Østergaard
- Center of Functionally Integrative NeuroscienceAarhus UniversityAarhusDenmark
- Department of Nuclear Medicine and PET CentreAarhus University HospitalAarhusDenmark
| | - Simon F. Eskildsen
- Center of Functionally Integrative NeuroscienceAarhus UniversityAarhusDenmark
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10
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Manhard MK, Bilgic B, Liao C, Han S, Witzel T, Yen YF, Setsompop K. Accelerated whole-brain perfusion imaging using a simultaneous multislice spin-echo and gradient-echo sequence with joint virtual coil reconstruction. Magn Reson Med 2019; 82:973-983. [PMID: 31069861 PMCID: PMC6692914 DOI: 10.1002/mrm.27784] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 04/03/2019] [Accepted: 04/04/2019] [Indexed: 12/13/2022]
Abstract
PURPOSE Dynamic susceptibility contrast imaging requires high temporal sampling, which poses limits on achievable spatial coverage and resolution. Additionally, more encoding-intensive multi-echo acquisitions for quantitative imaging are desired to mitigate contrast leakage effects, which further limits spatial encoding. We present an accelerated sequence that provides whole-brain coverage at an improved spatio-temporal resolution, to allow for dynamic quantitative R2 and R2 * mapping during contrast-enhanced imaging. METHODS A multi-echo spin and gradient-echo sequence was implemented with simultaneous multislice acquisition. Complementary k-space sampling between repetitions and joint virtual coil reconstruction were used along with a dynamic phase-matching technique to achieve high-quality reconstruction at 9-fold acceleration, which enabled 2 × 2 × 5 mm whole-brain imaging at TR of 1.5 to 1.7 seconds. The multi-echo images from this sequence were fit to achieve quantitative R2 and R2 * maps for each repetition, and subsequently used to find perfusion measures including cerebral blood flow and cerebral blood volume. RESULTS Images reconstructed using joint virtual coil show improved image quality and g-factor compared with conventional reconstruction methods, resulting in improved quantitative maps with a 9-fold acceleration factor and whole-brain coverage during the dynamic perfusion acquisition. CONCLUSION The method presented shows the advantage of using a joint virtual coil-GRAPPA reconstruction to allow for high acceleration factors while maintaining reliable image quality for quantitative perfusion mapping, with the potential to improve tumor diagnostics and monitoring.
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Affiliation(s)
- Mary Kate Manhard
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA
- Department of Radiology, Harvard Medical School, Boston, MA, USA
| | - Berkin Bilgic
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA
- Department of Radiology, Harvard Medical School, Boston, MA, USA
| | - Congyu Liao
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA
- Department of Radiology, Harvard Medical School, Boston, MA, USA
| | - SoHyun Han
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA
- Department of Radiology, Harvard Medical School, Boston, MA, USA
| | - Thomas Witzel
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA
- Department of Radiology, Harvard Medical School, Boston, MA, USA
| | - Yi-Fen Yen
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA
- Department of Radiology, Harvard Medical School, Boston, MA, USA
| | - Kawin Setsompop
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA
- Department of Radiology, Harvard Medical School, Boston, MA, USA
- Harvard-MIT Health Sciences and Technology, MIT, Cambridge, MA, USA
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11
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Lei H, Preitner F, Labouèbe G, Gruetter R, Thorens B. Glucose transporter 2 mediates the hypoglycemia-induced increase in cerebral blood flow. J Cereb Blood Flow Metab 2019; 39:1725-1736. [PMID: 29561214 PMCID: PMC6727137 DOI: 10.1177/0271678x18766743] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Glucose transporter 2 (Glut2)-positive cells are sparsely distributed in brain and play an important role in the stimulation of glucagon secretion in response to hypoglycemia. We aimed to determine if Glut2-positive cells can influence another response to hypoglycemia, i.e. increased cerebral blood flow (CBF). CBF of adult male mice devoid of Glut2, either globally (ripglut1:glut2-/-) or in the nervous system only (NG2KO), and their respective controls were studied under basal glycemia and insulin-induced hypoglycemia using quantitative perfusion magnetic resonance imaging at 9.4 T. The effect on CBF of optogenetic activation of hypoglycemia responsive Glut2-positive neurons of the paraventricular thalamic area was measured in mice expressing channelrhodopsin2 under the control of the Glut2 promoter. We found that in both ripglut1:glut2-/- mice and NG2KO mice, CBF in basal conditions was higher than in their respective controls and not further activated by hypoglycemia, as measured in the hippocampus, hypothalamus and whole brain. Conversely, optogenetic activation of Glut2-positive cells in the paraventricular thalamic nucleus induced a local increase in CBF similar to that induced by hypoglycemia. Thus, Glut2 expression in the nervous system is required for the control of CBF in response to changes in blood glucose concentrations.
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Affiliation(s)
- Hongxia Lei
- 1 AIT, Center for Biomedical Imaging (CIBM-AIT), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.,2 Department of Radiology, University of Geneva, Geneva, Switzerland
| | - Frédéric Preitner
- 3 Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland.,4 Mouse Metabolic Evaluation Facility, Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Gwenaël Labouèbe
- 3 Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Rolf Gruetter
- 1 AIT, Center for Biomedical Imaging (CIBM-AIT), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.,2 Department of Radiology, University of Geneva, Geneva, Switzerland.,5 Department of Radiology, University of Lausanne, Lausanne, Switzerland
| | - Bernard Thorens
- 3 Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
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12
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13
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Stadlbauer A, Mouridsen K, Doerfler A, Bo Hansen M, Oberndorfer S, Zimmermann M, Buchfelder M, Heinz G, Roessler K. Recurrence of glioblastoma is associated with elevated microvascular transit time heterogeneity and increased hypoxia. J Cereb Blood Flow Metab 2018; 38:422-432. [PMID: 28273720 PMCID: PMC5851132 DOI: 10.1177/0271678x17694905] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Dynamic susceptibility contrast (DSC) perfusion MRI provide information about differences in macro- and microvasculature when executed with gradient-echo (GE; sensitive to macrovasculature) and spin-echo (SE; sensitive to microvasculature) contrast. This study investigated whether there are differences between macro- and microvascular transit time heterogeneity (MVTH and µVTH) and tissue oxygen tension (PO2mit) in newly-diagnosed and recurrent glioblastoma. Fifty-seven patients with glioblastoma (25 newly-diagnosed/32 recurrent) were examined with GE- and SE-DSC perfusion sequences, and a quantitative blood-oxygen-level-dependent (qBOLD) approach. Maps of MVTH, µVTH and coefficient of variation (MCOV and µCOV) were calculated from GE- and SE-DSC data, respectively, using an extended flow-diffusion equation. PO2mit maps were calculated from qBOLD data. Newly-diagnosed and recurrent glioblastoma showed significantly lower ( P ≤ 0.001) µCOV values compared to both normal brain and macrovasculature (MCOV) of the lesions. Recurrent glioblastoma had significantly higher µVTH ( P = 0.014) and µCOV ( P = 0.039) as well as significantly lower PO2mit values ( P = 0.008) compared to newly-diagnosed glioblastoma. The macrovasculature, however, showed no significant differences. Our findings provide evidence of microvascular adaption in the disorganized tumor vasculature for retaining the metabolic demands in stress response of therapeutically-uncontrolled glioblastomas. Thus, µVTH and PO2mit mapping gives insight into the tumor microenvironment (vascular and hypoxic niches) responsible for therapy resistance.
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Affiliation(s)
- Andreas Stadlbauer
- 1 Department of Neurosurgery, University of Erlangen-Nürnberg, Erlangen, Germany.,2 Institute of Medical Radiology, University Clinic of St. Pölten, St. Pölten, Austria
| | - Kim Mouridsen
- 3 Center of Functionally Integrative Neuroscience and MIND Lab, Institute of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Arnd Doerfler
- 4 Department of Neuroradiology, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Mikkel Bo Hansen
- 3 Center of Functionally Integrative Neuroscience and MIND Lab, Institute of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Stefan Oberndorfer
- 5 Department of Neurology, University Clinic of St. Pölten, St. Pölten, Austria
| | - Max Zimmermann
- 1 Department of Neurosurgery, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Michael Buchfelder
- 1 Department of Neurosurgery, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Gertraud Heinz
- 2 Institute of Medical Radiology, University Clinic of St. Pölten, St. Pölten, Austria
| | - Karl Roessler
- 1 Department of Neurosurgery, University of Erlangen-Nürnberg, Erlangen, Germany
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14
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Rivera-Rivera LA, Schubert T, Knobloch G, Turski PA, Wieben O, Reeder SB, Johnson KM. Comparison of ferumoxytol-based cerebral blood volume estimates using quantitative R 1 and R2* relaxometry. Magn Reson Med 2017; 79:3072-3081. [PMID: 29096054 DOI: 10.1002/mrm.26975] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 08/24/2017] [Accepted: 09/28/2017] [Indexed: 12/11/2022]
Abstract
PURPOSE Cerebral perfusion is commonly assessed clinically with dynamic susceptibility contrast MRI using a bolus injection of gadolinium-based contrast agents, resulting in semi-quantitative values of cerebral blood volume (CBV). Steady-state imaging with ferumoxytol allows estimation of CBV with the potential for higher precision and accuracy. Prior CBV studies have focused on the signal disrupting T2* effects, but ferumoxytol also has high signal-enhancing T1 relaxivity. The purpose of this study was to investigate and compare CBV estimation using T1 and T2*, with the goal of understanding the contrast mechanisms and quantitative differences. METHODS Changes in R1 (1/T1 ) and R2* (1/ T2*) were measured after the administration of ferumoxytol using high-resolution quantitative approaches. Images were acquired at 3.0T and R1 was estimated from an ultrashort echo time variable flip angle approach, while R2* was estimated from a multiple gradient echo sequence. Twenty healthy volunteers were imaged at two doses. CBV was derived and compared from relaxometry in gray and white matter using different approaches. RESULTS R1 measurements showed a linear dependence of blood R1 with respect to dose in large vessels, in contrast to the nonlinear dose-dependence of blood R2* estimates. In the brain parenchyma, R2* showed linear dose-dependency whereas R1 showed nonlinearity. CBV calculations based on R2* changes in tissue and ferumoxytol blood concentration estimates based on R1 relaxivity showed the lowest variability in our cohort. CONCLUSIONS CBV measurements were successfully derived using a combined approach of R1 and R2* relaxometry. Magn Reson Med 79:3072-3081, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Leonardo A Rivera-Rivera
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Tilman Schubert
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
- Clinic of Radiology and Nuclear Medicine, Basel University Hospital, Basel, Switzerland
| | - Gesine Knobloch
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
- Departments of Biomedical Engineering, Medicine and Emergency Medicine, University of Wisconsin, Madison, Wisconsin, USA
| | - Patrick A Turski
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Oliver Wieben
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Scott B Reeder
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
- Departments of Biomedical Engineering, Medicine and Emergency Medicine, University of Wisconsin, Madison, Wisconsin, USA
| | - Kevin M Johnson
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
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15
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Stadlbauer A, Zimmermann M, Oberndorfer S, Doerfler A, Buchfelder M, Heinz G, Roessler K. Vascular Hysteresis Loops and Vascular Architecture Mapping in Patients with Glioblastoma treated with Antiangiogenic Therapy. Sci Rep 2017; 7:8508. [PMID: 28819189 PMCID: PMC5561153 DOI: 10.1038/s41598-017-09048-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 07/19/2017] [Indexed: 01/06/2023] Open
Abstract
In this study, we investigated the variability of vascular hysteresis loop (VHL) shapes and the spatial heterogeneity of neovascularization and microvascular alterations using vascular architecture mapping (VAM) in patients with recurrent glioblastoma during bevacizumab mono-therapy. VAM data were acquired in 13 patients suffering from recurrent glioblastoma prior to and 3 months after bevacizumab treatment onset using a dual contrast agent injections approach as part of routine MRI. Two patients were additionally examined after the first cycle of bevacizumab to check for early treatment response. VHLs were evaluated as biomarker maps of neovascularization activity: microvessel type indicator (MTI) and curvature (Curv) of the VHL-long-axis. Early response to bevacizumab was dominated by reduction of smaller microvasculature (around 10 µm). In the 3-month follow-up, responding tumors additionally showed a reduction in larger microvasculature (>20 µm). VAM biomarker images revealed spatially heterogeneous microvascular alterations during bevacizumab treatment. Responding, non-responding, progressive, and remote-progressive tumor areas were observed. MTI may be useful to predict responding and non-responding tumor regions, and Curv to assess severity of vasogenic edema. Analysis of VHLs in combination with VAM biomarkers may lead to a new perspective on investigating the spatial heterogeneity of neovascularization and microvascular alterations in glioblastoma during antiangiogenic therapy.
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Affiliation(s)
- Andreas Stadlbauer
- Department of Neurosurgery, University of Erlangen-Nürnberg, Erlangen, Germany. .,Institute of Medical Radiology, University Clinic of St. Pölten, St. Pölten, Austria.
| | - Max Zimmermann
- Department of Neurosurgery, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Stefan Oberndorfer
- Department of Neurology, University Clinic of St. Pölten, St. Pölten, Austria
| | - Arnd Doerfler
- Department of Neuroradiology, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Michael Buchfelder
- Department of Neurosurgery, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Gertraud Heinz
- Institute of Medical Radiology, University Clinic of St. Pölten, St. Pölten, Austria
| | - Karl Roessler
- Department of Neurosurgery, University of Erlangen-Nürnberg, Erlangen, Germany
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16
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Nielsen RB, Egefjord L, Angleys H, Mouridsen K, Gejl M, Møller A, Brock B, Brændgaard H, Gottrup H, Rungby J, Eskildsen SF, Østergaard L. Capillary dysfunction is associated with symptom severity and neurodegeneration in Alzheimer's disease. Alzheimers Dement 2017; 13:1143-1153. [PMID: 28343848 DOI: 10.1016/j.jalz.2017.02.007] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 01/13/2017] [Accepted: 02/13/2017] [Indexed: 01/18/2023]
Abstract
INTRODUCTION We examined whether cortical microvascular blood volume and hemodynamics in Alzheimer's disease (AD) are consistent with tissue hypoxia and whether they correlate with cognitive performance and the degree of cortical thinning. METHODS Thirty-two AD patients underwent cognitive testing, structural magnetic resonance imaging (MRI), and perfusion MRI at baseline and after 6 months. We measured cortical thickness, microvascular cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and capillary transit time heterogeneity (CTH) and estimated tissue oxygen tension (PtO2). RESULTS At baseline, poor cognitive performance and regional cortical thinning correlated with lower CBF and CBV, with higher MTT and CTH and with low PtO2 across the cortex. Cognitive decline over time was associated with increasing whole brain relative transit time heterogeneity (RTH = CTH/MTT). DISCUSSION Our results confirm the importance of microvascular pathology in AD. Deteriorating microvascular hemodynamics may cause hypoxia, which is known to precipitate amyloid retention.
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Affiliation(s)
- Rune B Nielsen
- Center of Functionally Integrative Neuroscience and MINDLab, Aarhus University, Aarhus, Denmark.
| | - Lærke Egefjord
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Hugo Angleys
- Center of Functionally Integrative Neuroscience and MINDLab, Aarhus University, Aarhus, Denmark
| | - Kim Mouridsen
- Center of Functionally Integrative Neuroscience and MINDLab, Aarhus University, Aarhus, Denmark
| | - Michael Gejl
- Department of Biomedicine, Aarhus University, Aarhus, Denmark; Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark
| | - Arne Møller
- PET-Center, Department of Nuclear Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Birgitte Brock
- Department of Biomedicine, Aarhus University, Aarhus, Denmark; Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark
| | - Hans Brændgaard
- Dementia Clinic, Department of Neurology, Aarhus University Hospital, Aarhus, Denmark
| | - Hanne Gottrup
- Dementia Clinic, Department of Neurology, Aarhus University Hospital, Aarhus, Denmark
| | - Jørgen Rungby
- Department of Endocrinology, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Simon F Eskildsen
- Center of Functionally Integrative Neuroscience and MINDLab, Aarhus University, Aarhus, Denmark
| | - Leif Østergaard
- Center of Functionally Integrative Neuroscience and MINDLab, Aarhus University, Aarhus, Denmark; Department of Neuroradiology, Aarhus University Hospital, Aarhus, Denmark
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17
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Tong Y, Lindsey KP, Hocke LM, Vitaliano G, Mintzopoulos D, Frederick BD. Perfusion information extracted from resting state functional magnetic resonance imaging. J Cereb Blood Flow Metab 2017; 37:564-576. [PMID: 26873885 PMCID: PMC5381451 DOI: 10.1177/0271678x16631755] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
It is widely known that blood oxygenation level dependent (BOLD) contrast in functional magnetic resonance imaging (fMRI) is an indirect measure for neuronal activations through neurovascular coupling. The BOLD signal is also influenced by many non-neuronal physiological fluctuations. In previous resting state (RS) fMRI studies, we have identified a moving systemic low frequency oscillation (sLFO) in BOLD signal and were able to track its passage through the brain. We hypothesized that this seemingly intrinsic signal moves with the blood, and therefore, its dynamic patterns represent cerebral blood flow. In this study, we tested this hypothesis by performing Dynamic Susceptibility Contrast (DSC) MRI scans (i.e. bolus tracking) following the RS scans on eight healthy subjects. The dynamic patterns of sLFO derived from RS data were compared with the bolus flow visually and quantitatively. We found that the flow of sLFO derived from RS fMRI does to a large extent represent the blood flow measured with DSC. The small differences, we hypothesize, are largely due to the difference between the methods in their sensitivity to different vessel types. We conclude that the flow of sLFO in RS visualized by our time delay method represents the blood flow in the capillaries and veins in the brain.
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Affiliation(s)
- Yunjie Tong
- 1 McLean Imaging Center, McLean Hospital, Belmont, MA, USA.,2 Department of Psychiatry, Harvard University Medical School, Boston, MA, USA
| | - Kimberly P Lindsey
- 1 McLean Imaging Center, McLean Hospital, Belmont, MA, USA.,2 Department of Psychiatry, Harvard University Medical School, Boston, MA, USA
| | - Lia M Hocke
- 1 McLean Imaging Center, McLean Hospital, Belmont, MA, USA.,3 Department of Radiology, University of Calgary, Calgary, Alberta, Canada
| | - Gordana Vitaliano
- 1 McLean Imaging Center, McLean Hospital, Belmont, MA, USA.,2 Department of Psychiatry, Harvard University Medical School, Boston, MA, USA
| | - Dionyssios Mintzopoulos
- 1 McLean Imaging Center, McLean Hospital, Belmont, MA, USA.,2 Department of Psychiatry, Harvard University Medical School, Boston, MA, USA
| | - Blaise deB Frederick
- 1 McLean Imaging Center, McLean Hospital, Belmont, MA, USA.,2 Department of Psychiatry, Harvard University Medical School, Boston, MA, USA
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18
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Pizzolato M, Boutelier T, Deriche R. Perfusion deconvolution in DSC-MRI with dispersion-compliant bases. Med Image Anal 2017; 36:197-215. [DOI: 10.1016/j.media.2016.12.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 12/05/2016] [Accepted: 12/05/2016] [Indexed: 11/27/2022]
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19
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Blasel S, Zagorcic A, Jurcoane A, Bähr O, Wagner M, Harter PN, Hattingen E. Perfusion MRI in the Evaluation of Suspected Glioblastoma Recurrence. J Neuroimaging 2015; 26:116-23. [PMID: 25907688 DOI: 10.1111/jon.12247] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 03/01/2015] [Indexed: 11/30/2022] Open
Abstract
PURPOSE Treatment-related changes (TRC) often imitate tumor progression in glioblastomas. Increased regional cerebral blood volume (rCBV) can differentiate tumor progression from TRC after the standardized first-line radiochemotherapy, but information about diagnostic accuracy of rCBV for patients without any clinical selection criteria is limited. Therefore, we aimed to evaluate if rCBV can differentiate between TRC and tumor progression irrespective of preceding therapies and number of tumor progressions. METHODS We analyzed mean and maximum rCBV from the enhancing areas normalized to the contralateral white matter in 44 pretreated glioblastomas with MR-morphological tumor progression. The diagnosis (real progression vs. TRC) was determined by histopathology or by clinical/MRI-follow-up. We performed nonparametric tests, receiver operating characteristics (ROC), and Kaplan-Meier analysis. RESULTS Significant differences between tumor progression (N = 37) and TRC (N = 7) were found for rCBVmean (2.44 ± 1.05 vs. 1.69 ± .56, P < .03) and rCBVmax (3.40 ± 1.25 vs. 2.21 ± .62, P < .0007). A rCBVmax of 2.6 had 78% sensitivity and 86% specificity to detect tumor progression. Neither rCBVmean nor rCBVmax was predictive for the patient overall survival (OS). There were no statistically different rCBVmean and rCBVmax between the first and further tumor progressions. CONCLUSIONS The rCBVmax differentiates tumor progression from TRC in unselected recurrent glioblastomas, but it is not predictive for the OS.
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Affiliation(s)
- Stella Blasel
- Institute of Neuroradiology, Goethe-University Hospital Frankfurt, Schleusenweg 2-16, 60528, Frankfurt, Germany
| | - Andrea Zagorcic
- Institute of Neuroradiology, Goethe-University Hospital Frankfurt, Schleusenweg 2-16, 60528, Frankfurt, Germany
| | - Alina Jurcoane
- Institute of Neuroradiology, Goethe-University Hospital Frankfurt, Schleusenweg 2-16, 60528, Frankfurt, Germany
| | - Oliver Bähr
- Dr. Senckenberg Institute of Neurooncology, Goethe-University Hospital Frankfurt, Schleusenweg 2-16, 60528, Frankfurt, Germany
| | - Marlies Wagner
- Institute of Neuroradiology, Goethe-University Hospital Frankfurt, Schleusenweg 2-16, 60528, Frankfurt, Germany
| | - Patrick N Harter
- Edinger Institute, Institute of Neurology, Goethe-University Frankfurt, Heinrich Hoffmann Strasse 7, 60528, Frankfurt, Germany
| | - Elke Hattingen
- Institute of Neuroradiology, Goethe-University Hospital Frankfurt, Schleusenweg 2-16, 60528, Frankfurt, Germany
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Roldan-Valadez E, Lopez-Mejia M. Current concepts on magnetic resonance imaging (MRI) perfusion-diffusion assessment in acute ischaemic stroke: a review & an update for the clinicians. Indian J Med Res 2015; 140:717-28. [PMID: 25758570 PMCID: PMC4365345 DOI: pmid/25758570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Recently, several medical societies published joint statements about imaging recommendations for acute stroke and transient ischaemic attack patients. In following with these published guidelines, we considered it appropriate to present a brief, practical and updated review of the most relevant concepts on the MRI assessment of acute stroke. Basic principles of the clinical interpretation of diffusion, perfusion, and MRI angiography (as part of a global MRI protocol) are discussed with accompanying images for each sequence. Brief comments on incidence and differential diagnosis are also included, together with limitations of the techniques and levels of evidence. The purpose of this article is to present knowledge that can be applied in day-to-day clinical practice in specialized stroke units or emergency rooms to attend patients with acute ischaemic stroke or transient ischaemic attack according to international standards.
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Bisdas S, Braun C, Skardelly M, Schittenhelm J, Teo TH, Thng CH, Klose U, Koh TS. Correlative assessment of tumor microcirculation using contrast-enhanced perfusion MRI and intravoxel incoherent motion diffusion-weighted MRI: is there a link between them? NMR IN BIOMEDICINE 2014; 27:1184-1191. [PMID: 25088433 DOI: 10.1002/nbm.3172] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Revised: 07/03/2014] [Accepted: 07/03/2014] [Indexed: 06/03/2023]
Abstract
The purpose of this study was to correlate intravoxel incoherent motion (IVIM) imaging with classical perfusion-weighted MRI metrics in human gliomas. Parametric images for slow diffusion coefficient (D), fast diffusion coefficient (D*), and fractional perfusion-related volume (f) in patients with high-grade gliomas were generated. Maps of Fp (plasma flow), vp (vascular plasma volume), PS (permeability surface-area product), ve (extravascular, extracellular volume), E (extraction ratio), ke (influx ratio into the interstitium), and tc (vascular transit time) from dynamic contrast-enhanced (DCE) and dynamic susceptibility contrast-enhanced (DSC) MRI were also generated. A region-of-interest analysis on the contralateral healthy white matter and on the tumor areas was performed and the extracted parameter values were tested for any significant differences among tumor grades or any correlations. Only f could be significantly correlated to DSC-derived vp and tc in healthy brain tissue. Concerning the tumor regions, Fp was significantly positively correlated with D* and inversely correlated with f in DSC measurements. The D*, f, and f × D* values in the WHO grade III gliomas were non-significantly different from those in the grade IV gliomas. There was a trend to significant negative correlations between f and PS as well as between f × D* and ke in DCE experiments. Presumably due to different theoretical background, tracer properties and modeling of the tumor vasculature in the IVIM theory, there is no clearly evident link between D*, f and DSC- and DCE-derived metrics.
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Affiliation(s)
- Sotirios Bisdas
- Department of Neuroradiology, Eberhard Karls University, Tübingen, Germany
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Jahng GH, Li KL, Ostergaard L, Calamante F. Perfusion magnetic resonance imaging: a comprehensive update on principles and techniques. Korean J Radiol 2014; 15:554-77. [PMID: 25246817 PMCID: PMC4170157 DOI: 10.3348/kjr.2014.15.5.554] [Citation(s) in RCA: 126] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Accepted: 07/05/2014] [Indexed: 12/16/2022] Open
Abstract
Perfusion is a fundamental biological function that refers to the delivery of oxygen and nutrients to tissue by means of blood flow. Perfusion MRI is sensitive to microvasculature and has been applied in a wide variety of clinical applications, including the classification of tumors, identification of stroke regions, and characterization of other diseases. Perfusion MRI techniques are classified with or without using an exogenous contrast agent. Bolus methods, with injections of a contrast agent, provide better sensitivity with higher spatial resolution, and are therefore more widely used in clinical applications. However, arterial spin-labeling methods provide a unique opportunity to measure cerebral blood flow without requiring an exogenous contrast agent and have better accuracy for quantification. Importantly, MRI-based perfusion measurements are minimally invasive overall, and do not use any radiation and radioisotopes. In this review, we describe the principles and techniques of perfusion MRI. This review summarizes comprehensive updated knowledge on the physical principles and techniques of perfusion MRI.
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Affiliation(s)
- Geon-Ho Jahng
- Department of Radiology, Kyung Hee University Hospital at Gangdong, College of Medicine, Kyung Hee University, Seoul 134-727, Korea
| | - Ka-Loh Li
- Wolfson Molecular Imaging Center, The University of Manchester, Manchester M20 3LJ, UK
| | - Leif Ostergaard
- Center for Functionally Integrative Neuroscience, Department of Neuroradiology, Aarhus University Hospital, Aarhus C 8000, Denmark
| | - Fernando Calamante
- Florey Institute of Neuroscience and Mental Health, Heidelberg, Victoria 3084, Australia
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Shiroishi MS, Castellazzi G, Boxerman JL, D'Amore F, Essig M, Nguyen TB, Provenzale JM, Enterline DS, Anzalone N, Dörfler A, Rovira À, Wintermark M, Law M. Principles of T2*-weighted dynamic susceptibility contrast MRI technique in brain tumor imaging. J Magn Reson Imaging 2014; 41:296-313. [DOI: 10.1002/jmri.24648] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Accepted: 04/03/2014] [Indexed: 01/17/2023] Open
Affiliation(s)
- Mark S. Shiroishi
- Keck School of Medicine; University of Southern California; Los Angeles California USA
| | - Gloria Castellazzi
- Department of Industrial and Information Engineering; University of Pavia; Pavia Italy
- Brain Connectivity Center, IRCCS “C. Mondino Foundation,”; Pavia Italy
| | - Jerrold L. Boxerman
- Warren Alpert Medical School of Brown University; Providence Rhode Island USA
| | - Francesco D'Amore
- Keck School of Medicine; University of Southern California; Los Angeles California USA
- Department of Neuroradiology; IRCCS “C. Mondino Foundation,” University of Pavia; Pavia Italy
| | - Marco Essig
- University of Manitoba's Faculty of Medicine; Winnipeg Manitoba Canada
| | - Thanh B. Nguyen
- Faculty of Medicine, Ottawa University; Ottawa Ontario Canada
| | - James M. Provenzale
- Duke University Medical Center; Durham North Carolina USA
- Emory University School of Medicine; Atlanta Georgia USA
| | | | | | - Arnd Dörfler
- University of Erlangen-Nuremberg, Erlangen; Germany
| | - Àlex Rovira
- Vall d'Hebron University Hospital; Barcelona Spain
| | - Max Wintermark
- School of Medicine; University of Virginia; Charlottesville Virginia USA
| | - Meng Law
- Keck School of Medicine; University of Southern California; Los Angeles California USA
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Akgoz A, Rahman R, You H, Qu J, Hamdan A, Seethamraju RT, Wen PY, Young GS. Spin-echo echo-planar perfusion prior to chemoradiation is a strong independent predictor of progression-free and overall survival in newly diagnosed glioblastoma. J Neurooncol 2014; 119:111-9. [PMID: 24792644 DOI: 10.1007/s11060-014-1454-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Accepted: 04/20/2014] [Indexed: 11/29/2022]
Abstract
Spin-echo echo planar (EP) perfusion weighted imaging (SE-PWI) has been demonstrated to be more selective than gradient-echo EP PWI for blood volume in microvessels the size of glioma neocapillaries, but it has not been comprehensively studied in human clinical use. We assessed whether SE-PWI before and after initiating chemoradiation can stratify patients with respect to progression free survival (PFS) and overall survival (OS). Sixty-eight patients with newly diagnosed glioblastoma (mean age 58.3, 36 males) were included in analysis. SE EP cerebral blood volumes (SE-CBVs) in enhancing and nonenhancing tumor, normalized to contralateral normal appearing white matter (SE-nCBV), were assessed at baseline and after initial chemoradiation. SE-nCBV parameters predictive of PFS and OS were identified in univariate and multivariate Cox proportional hazards models. Multivariate analysis demonstrated that baseline tumor mean SE-nCBV was predictive of PFS (p = 0.038) and OS (p = 0.004). Within the patient sample, baseline tumor mean SE-nCBV <2.0 predicted longer patient PFS (median 47.0 weeks, p < 0.001) and OS (median 98.6 weeks, p = 0.003) compared with baseline mean SE-nCBV >2.0 (median PFS 25.3, median OS 56.0 weeks). Exploratory multi-group stratification demonstrated that very high (>4.0) tumor SE-nCBV was associated with worse patient OS than intermediate high (>2.0, <4.0) SE-nCBV (p = 0.025). Baseline mean SE-nCBV can stratify patients for PFS and OS prior to initiation of chemoradiation, which may help select patients who require closer surveillance. Our exploratory analysis indicates a magnitude-dependent relationship between baseline SE-nCBV and OS.
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Affiliation(s)
- Ayca Akgoz
- Department of Radiology, Brigham and Women's Hospital, 75 Francis Street, Boston, MA, 02115, USA
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Iv M, Fischbein NJ, Zaharchuk G. Association of Developmental Venous Anomalies with Perfusion Abnormalities on Arterial Spin Labeling and Bolus Perfusion-Weighted Imaging. J Neuroimaging 2014; 25:243-250. [PMID: 24717021 DOI: 10.1111/jon.12119] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 02/01/2014] [Accepted: 03/02/2014] [Indexed: 11/28/2022] Open
Affiliation(s)
- Michael Iv
- Department of Radiology; Stanford University and Stanford University Medical Center; Stanford CA
| | - Nancy J. Fischbein
- Department of Radiology; Stanford University and Stanford University Medical Center; Stanford CA
| | - Greg Zaharchuk
- Department of Radiology; Stanford University and Stanford University Medical Center; Stanford CA
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Wong AM, Yan FX, Liu HL. Comparison of three-dimensional pseudo-continuous arterial spin labeling perfusion imaging with gradient-echo and spin-echo dynamic susceptibility contrast MRI. J Magn Reson Imaging 2013; 39:427-33. [PMID: 23677620 DOI: 10.1002/jmri.24178] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Accepted: 03/27/2013] [Indexed: 11/10/2022] Open
Abstract
PURPOSE To compare the relative cerebral blood flow (CBF) obtained by pseudo-continuous arterial spin labeling sequence incorporated with volumetric fast spin-echo readout (3D-PCASL) with those by gradient-echo (GE) and spin-echo (SE) dynamic susceptibility contrast (DSC) MRI. MATERIALS AND METHODS Thirty patients with various neurological diseases participated in this study. In addition to 3D-PCASL, 15 patients received GE-DSC and the others received SE-DSC imaging on a 3 Tesla scanner. A cortical gray matter (GM) to white matter (WM) and a thalamus (TM) to WM CBF ratio were determined from each perfusion scan. In addition, histograms of relative CBF distributions were obtained from each method for comparison. RESULTS Significant correlations of CBF ratios were found between 3D-PCASL and the two DSC methods (P < 0.05). The 3D-PCASL resulted in GM/WM CBF ratios similar to SE-DSC but significantly smaller than GE-DSC (P = 2.3 × 10(-7) ). TM/WM CBF ratio obtained by 3D-PCASL was significantly smaller than those by GE- and SE-DSC (P = 4.1 × 10(-7) and 1.2 × 10(-6) , respectively). The histogram of relative CBF maps obtained from SE-DSC, after applied spatial smoothing, agreed well with that from 3D-PCASL. CONCLUSION This study suggested that perfusion images obtained from 3D-PCASL exhibited significant correlations with DSC-MRI, with greater microvascular weighting like SE-DSC.
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Affiliation(s)
- Alex M Wong
- Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital at Keelung, Linkou Medical Center, Taiwan; College of Medicine, Chang Gung University, Taoyuan, Taiwan
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Schmiedeskamp H, Andre JB, Straka M, Christen T, Nagpal S, Recht L, Thomas RP, Zaharchuk G, Bammer R. Simultaneous perfusion and permeability measurements using combined spin- and gradient-echo MRI. J Cereb Blood Flow Metab 2013; 33:732-43. [PMID: 23462570 PMCID: PMC3652702 DOI: 10.1038/jcbfm.2013.10] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The purpose of this study was to estimate magnetic resonance imaging-based brain perfusion parameters from combined multiecho spin-echo and gradient-echo acquisitions, to correct them for T₁₋, T₂₋, and T₂₋*-related contrast agent (CA) extravasation effects, and to simultaneously determine vascular permeability. Perfusion data were acquired using a combined multiecho spin- and gradient-echo (SAGE) echo-planar imaging sequence, which was corrected for CA extravasation effects using pharmacokinetic modeling. The presented method was validated in simulations and brain tumor patients, and compared with uncorrected single-echo and multiecho data. In the presence of CA extravasation, uncorrected single-echo data resulted in underestimated CA concentrations, leading to underestimated single-echo cerebral blood volume (CBV) and mean transit time (MTT). In contrast, uncorrected multiecho data resulted in overestimations of CA concentrations, CBV, and MTT. The correction of CA extravasation effects resulted in CBV and MTT estimates that were more consistent with the underlying tissue characteristics. Spin-echo perfusion data showed reduced large-vessel blooming effects, facilitating better distinction between increased CBV due to active tumor progression and elevated CBV due to the presence of cortical vessels in tumor proximity. Furthermore, extracted permeability parameters were in good agreement with elevated T1-weighted postcontrast signal values.
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Affiliation(s)
- Heiko Schmiedeskamp
- Lucas Center, Department of Radiology, Stanford University, Stanford, California 94305-5488, USA
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Wirestam R. Using contrast agents to obtain maps of regional perfusion and capillary wall permeability. ACTA ACUST UNITED AC 2012. [DOI: 10.2217/iim.12.24] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Fischer MA, Donati OF, Reiner CS, Hunziker R, Nanz D, Boss A. Feasibility of semiquantitative liver perfusion assessment by ferucarbotran bolus injection in double-contrast hepatic MRI. J Magn Reson Imaging 2012; 36:168-76. [PMID: 22334302 DOI: 10.1002/jmri.23611] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Accepted: 01/11/2012] [Indexed: 01/15/2023] Open
Abstract
PURPOSE To evaluate the feasibility of semiquantitative measurement of liver perfusion from analysis of ferucarbotran induced signal-dynamics in double-contrast liver MR-imaging (DC-MRI). MATERIALS AND METHODS In total 31 patients (21 men; 58 ± 10 years) including 18 patients with biopsy proven liver cirrhosis prospectively underwent clinically indicated DC-MRI at 1.5 Tesla (T) with dynamic T2-weighted gradient-echo imaging after ferucarbotran bolus injection. Breathing artefacts in tissue and input time curves were reduced by Savitzky-Golay-filtering and semiquantitative perfusion maps were calculated using a model free approach. Hepatic blood flow index (HBFI) and splenic blood flow index (SBFI) were determined by normalization of arbitrary perfusion values to the perfusion of the erector spinae muscle resulting in a semiquantitative perfusion measure. RESULTS In 30 of 31 patients the evaluated protocol could successfully be applied. Mean HBF was 7.7 ± 2.46 (range, 4.6-12.8) and mean SBF was 13.20 ± 2.57 (range, 8.5-17.8). A significantly lower total HBF was seen in patients with cirrhotic livers as compared to patients with noncirrhotic livers (P < 0.05). In contrast, similar SBF was observed in cirrhotic and noncirrhotic patients (P = 0.11). CONCLUSION Capturing the signal dynamics during bolus injection of ferucarbotran in DC-MRI of the liver allows for semiquantitative assessment of hepatic perfusion that may be helpful for a more precise characterisation of liver cirrhosis and focal liver lesions.
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Affiliation(s)
- Michael A Fischer
- Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Zurich, Switzerland.
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Schmiedeskamp H, Straka M, Newbould RD, Zaharchuk G, Andre JB, Olivot JM, Moseley ME, Albers GW, Bammer R. Combined spin- and gradient-echo perfusion-weighted imaging. Magn Reson Med 2011; 68:30-40. [PMID: 22114040 DOI: 10.1002/mrm.23195] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 07/21/2011] [Accepted: 08/02/2011] [Indexed: 11/09/2022]
Abstract
In this study, a spin- and gradient-echo echo-planar imaging (SAGE EPI) MRI pulse sequence is presented that allows simultaneous measurements of gradient-echo and spin-echo dynamic susceptibility-contrast perfusion-weighted imaging data. Following signal excitation, five readout trains were acquired using spin- and gradient-echo echo-planar imaging, all of them with echo times of less than 100 ms. Contrast agent concentrations in brain tissue were determined based on absolute R2* and R(2) estimates rather than relative changes in the signals of individual echo trains, producing T(1)-independent dynamic susceptibility-contrast perfusion-weighted imaging data. Moreover, this acquisition technique enabled vessel size imaging through the simultaneous quantification of R2* and R(2), without an increase in acquisition time. In this work, the concepts of SAGE EPI pulse sequence and results in stroke and tumor imaging are presented. Overall, SAGE EPI combined the advantages of higher sensitivity to contrast agent passage of gradient-echo perfusion-weighted imaging with better microvascular selectivity of spin-echo perfusion-weighted imaging.
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Affiliation(s)
- Heiko Schmiedeskamp
- Department of Radiology, Stanford University, Lucas Center, Stanford, California, USA
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Unsupervised multiparametric classification of dynamic susceptibility contrast imaging: Study of the healthy brain. Neuroimage 2011; 56:858-64. [DOI: 10.1016/j.neuroimage.2011.03.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Revised: 02/23/2011] [Accepted: 03/10/2011] [Indexed: 11/17/2022] Open
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Huang J, Wang AM, Shetty A, Maitz AH, Yan D, Doyle D, Richey K, Park S, Pieper DR, Chen PY, Grills IS. Differentiation between intra-axial metastatic tumor progression and radiation injury following fractionated radiation therapy or stereotactic radiosurgery using MR spectroscopy, perfusion MR imaging or volume progression modeling. Magn Reson Imaging 2011; 29:993-1001. [PMID: 21571478 DOI: 10.1016/j.mri.2011.04.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Revised: 03/28/2011] [Accepted: 04/04/2011] [Indexed: 10/18/2022]
Abstract
OBJECTIVE To determine the accuracy of magnetic resonance spectroscopy (MRS), perfusion MR imaging (MRP), or volume modeling in distinguishing tumor progression from radiation injury following radiotherapy for brain metastasis. METHODS Twenty-six patients with 33 intra-axial metastatic lesions who underwent MRS (n=41) with or without MRP (n=32) after cranial irradiation were retrospectively studied. The final diagnosis was based on histopathology (n=4) or magnetic resonance imaging (MRI) follow-up with clinical correlation (n=29). Cho/Cr (choline/creatinine), Cho/NAA (choline/N-acetylaspartate), Cho/nCho (choline/contralateral normal brain choline) ratios were retrospectively calculated for the multi-voxel MRS. Relative cerebral blood volume (rCBV), relative peak height (rPH) and percentage of signal-intensity recovery (PSR) were also retrospectively derived for the MRPs. Tumor volumes were determined using manual segmentation method and analyzed using different volume progression modeling. Different ratios or models were tested and plotted on the receiver operating characteristic curve (ROC), with their performances quantified as area under the ROC curve (AUC). MRI follow-up time was calculated from the date of initial radiotherapy until the last MRI or the last MRI before surgical diagnosis. RESULTS Median MRI follow-up was 16 months (range: 2-33). Thirty percent of lesions (n=10) were determined to be radiation injury; 70% (n=23) were determined to be tumor progression. For the MRS, Cho/nCho had the best performance (AUC of 0.612), and Cho/nCho >1.2 had 33% sensitivity and 100% specificity in predicting tumor progression. For the MRP, rCBV had the best performance (AUC of 0.802), and rCBV >2 had 56% sensitivity and 100% specificity. The best volume model was percent increase (AUC of 0.891); 65% tumor volume increase had 100% sensitivity and 80% specificity. CONCLUSION Cho/nCho of MRS, rCBV of MRP, and percent increase of MRI volume modeling provide the best discrimination of intra-axial metastatic tumor progression from radiation injury for their respective modalities. Cho/nCho and rCBV appear to have high specificities but low sensitivities. In contrast, percent volume increase of 65% can be a highly sensitive and moderately specific predictor for tumor progression after radiotherapy. Future incorporation of 65% volume increase as a pretest selection criterion may compensate for the low sensitivities of MRS and MRP.
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Affiliation(s)
- Jiayi Huang
- Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI 48073, USA
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Holveck A, Grand S, Boini S, Kirchin M, Le Bas JF, Dietemann JL, Bracard S, Kremer S. Dynamic susceptibility contrast-enhanced MRI evaluation of cerebral intraventricular tumors: preliminary results. J Neuroradiol 2011; 37:269-75. [PMID: 20435349 DOI: 10.1016/j.neurad.2009.11.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2009] [Revised: 11/11/2009] [Accepted: 11/12/2009] [Indexed: 10/19/2022]
Abstract
INTRODUCTION The aims of the present study were to determine the perfusion characteristics of several types of intraventricular tumors and to evaluate the usefulness of dynamic contrast-enhanced MRI in making the differential diagnosis. METHODS A total of 28 patients with intraventricular tumors (five meningiomas, five papillomas, three ependymomas, four subependymomas, seven central neurocytomas, two subependymal giant cell astrocytomas and two metastases) underwent conventional and dynamic susceptibility contrast-enhanced MRI. Cerebral blood volume (CBV) maps were obtained and the relative CBV (rCBV) calculated for each tumor. Mean rCBV(max) values were compared across the different types of tumors (ANOVA, P=0.05). RESULTS Intraventricular tumors presented with three different patterns of vascularization: highly vascularized tumors (mean rCBV(max)>3), including papillomas, meningiomas and renal carcinoma metastases; poorly vascularized tumors (mean rCBV(max)<2), including ependymomas and subependymomas; and intermediately vascularized tumors (mean rCBV(max)>2 but<3), including central neurocytomas and lung metastases. There was a significant difference between the highly vascularized (papillomas, meningiomas) and poorly vascularized (subependymomas) tumors. In cases of suspected meningioma, papilloma or neurocytoma, low rCBV values (<3) point to a diagnosis of neurocytoma rather than either of the other tumor types. CONCLUSION Susceptibility contrast-enhanced MRI can provide additional information on the vascularization of intraventricular cerebral tumors and may help in making the differential diagnosis.
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Affiliation(s)
- A Holveck
- Neuroradiology Department, hôpital Central, CHU de Nancy, 54000 Nancy, France.
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Fayed N, Dávila J, Oliveros A, Medrano J, Castillo J. Correlation of findings in advanced MR techniques with global severity scales in patients with some grade of cognitive impairment. Neurol Res 2010; 32:157-65. [PMID: 20158954 DOI: 10.1179/174313209x405164] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
INTRODUCTION Some previous studies in patients with mild cognitive impairment and Alzheimer's disease have probed changes in the results of (1)H magnetic resonance spectroscopy and perfusion- and diffusion-weighted imaging. The purpose of this work was to correlate the results of perfusion- and diffusion-weighted imaging and magnetic resonance spectroscopy with the results of two global severity scales in cognitive impairment: the clinical dementia rating (CDR) and the global deterioration scale (GDS). PATIENTS AND METHODS We evaluated 87 patients with cognitive impairment of diverse grade (35 men and 52 women; mean age, 70.2 +/- 8.5 years old). All patients were evaluated by a neurological team in our hospital. They applied both global severity scales (CDR and GDS) and referred the patients to our diagnostic imaging department to make a cerebral magnetic resonance imaging study and studies of diffusion- and perfusion-weighted imaging and magnetic resonance spectroscopy. We excluded patients with history of Parkinson's disease, frontotemporal dementia, cerebrovascular disease, intracranial tumors, hydrocephaly, epilepsy, alcoholism and psychiatric disorders. Magnetic resonance spectroscopy was carried out in the left occipital cortex and in the posterior cingulate gyrus. The evaluated metabolites were N-acetylaspartate (NAA), choline (Cho), creatine (Cr) and myo-inositol (mI). After diffusion-weighted imaging, we calculated apparent diffusion coefficient values in the region of interest located in hippocampi, white matter of temporal lobes, occipital lobes, parietal lobes, frontal lobes and posterior cingulate gyrus of both hemispheres. In perfusion-weighted imaging, we calculated the relative cerebral blood volume in hippocampi, gray matter of frontal lobes, occipital lobes, temporoparietal regions, posterior cingulate gyri and somatic-sensorial cortex. We used Spearman coefficient to analyse the correlation among the different factors. Statistical analysis was made with SPSS 14 software. RESULTS We found 33 patients with Alzheimer's disease and 54 with mild cognitive impairment. The Spearman coefficient had statistical significance in the correlation of CDR and GDS (R(2)=0.596, p<0.001). Magnetic resonance spectroscopy showed a good correlation between ratios of NAA/Cr and NAA/mI with CDR and GDS in both evaluated regions and a weak correlation between Cho/Cr in the left occipital lobe and GDS. In diffusion-weighted imaging, we found a weak correlation between GDS and apparent diffusion coefficient values in hippocampi, temporal lobes, left frontal lobe and left occipital lobe. Finally, perfusion showed a weak correlation between GDS and relative cerebral blood volume in occipital lobes and posterior cingulate gyrus. CONCLUSION In patients with cognitive impairment, there is a good correlation between CDR and GDS. The tool that showed the closest correlation with the clinical scales (CDR and GDS) was magnetic resonance spectroscopy in the left occipital cortex and posterior cingulate gyrus. Perfusion- and diffusion-weighted imaging are tools with a weak correlation with clinical scales, GDS being unique that gave us significant statistical results; this could be explained by the major number of items considered for cognitive impairment (GDS 2 and 3) compared with CDR (CDR 0.5). Magnetic resonance spectroscopy can be used in the diagnostic, following and evaluation of the response to the treatment in patients with cognitive impairment (mild cognitive impairment and Alzheimer's disease), complementing the information obtained in the clinical evaluation.
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Affiliation(s)
- Nicolás Fayed
- Department of Radiology, Quiron Hospital, Paseo Mariano Renovales s/n, Zaragoza 50006, Spain
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Gasparovic CM, Roldan CA, Sibbitt WL, Qualls CR, Mullins PG, Sharrar JM, Yamamoto JJ, Bockholt HJ. Elevated cerebral blood flow and volume in systemic lupus measured by dynamic susceptibility contrast magnetic resonance imaging. J Rheumatol 2010; 37:1834-43. [PMID: 20551095 DOI: 10.3899/jrheum.091276] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
OBJECTIVE Studies that have examined abnormalities in cerebral blood flow (CBF) in patients with systemic lupus erythematosus (SLE) reported CBF relative to a region assumed to be normal in the brain. We examined the absolute differences in both regional CBF and cerebral blood volume (CBV) between patients with SLE and healthy controls. METHODS CBF and CBV were measured with dynamic susceptibility contrast (DSC) magnetic resonance imaging (MRI), a technique that provides an alternative to radionuclide perfusion studies and permits quantitative anatomic, CBF, and CBV imaging in a single scanning session. CBF and CBV were measured in lesions and in normal-appearing tissue in the major cerebral and subcortical brain regions. Unlike most perfusion studies in SLE, CBF and CBV values were not normalized to a region of the brain assumed to be healthy. RESULTS CBF and CBV within MRI-visible lesions were markedly reduced relative to surrounding normal-appearing white matter. CBF and CBV in normal-appearing tissue were both higher in SLE patient groups, with or without lesions, relative to the control group. CONCLUSION DSC MRI, without normalization to a region presumed to be healthy, revealed that CBF and CBV in normal-appearing tissue in patients with SLE was higher than CBF and CBV in controls. Since this finding was made in subgroups of patients with and without lesions, the higher CBF and CBV appear to precede lesion pathology.
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Affiliation(s)
- Charles M Gasparovic
- Department of Psychology, Divisions of Cardiology and Rheumatology, University of New Mexico, 1101 Yale Blvd. NE, Albuquerque, NM 87106, USA.
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Knutsson L, Ståhlberg F, Wirestam R. Absolute quantification of perfusion using dynamic susceptibility contrast MRI: pitfalls and possibilities. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2009; 23:1-21. [DOI: 10.1007/s10334-009-0190-2] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2009] [Revised: 11/11/2009] [Accepted: 11/12/2009] [Indexed: 10/20/2022]
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Gasparetto EL, Pawlak MA, Patel SH, Huse J, Woo JH, Krejza J, Rosenfeld MR, O'Rourke DM, Lustig R, Melhem ER, Wolf RL. Posttreatment Recurrence of Malignant Brain Neoplasm: Accuracy of Relative Cerebral Blood Volume Fraction in Discriminating Low from High Malignant Histologic Volume Fraction. Radiology 2009; 250:887-96. [DOI: 10.1148/radiol.2502071444] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Young GS, Setayesh K. Spin-echo echo-planar perfusion MR imaging in the differential diagnosis of solitary enhancing brain lesions: distinguishing solitary metastases from primary glioma. AJNR Am J Neuroradiol 2008; 30:575-7. [PMID: 19095787 DOI: 10.3174/ajnr.a1239] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Unlike the more widely reported gradient-echo echo-planar perfusion-weighted imaging (EPI-PWI) technique, spin-echo (SE) EPI relative cerebral blood volume maps select for blood volume in microvessels <8 microm in diameter. This first report of SE-EPI PWI for distinguishing brain metastasis from high-grade glioma demonstrated 88% sensitivity and 72% specificity in 83 patients. We discuss differences in microvessel architecture between high-grade glioma and brain metastasis that may explain the surprising success of SE-EPI in this application and may deserve further investigation.
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Affiliation(s)
- G S Young
- Department of Radiology of Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
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Fayed N, Dávila J, Oliveros A, Castillo J, Medrano JJ. Utility of different MR modalities in mild cognitive impairment and its use as a predictor of conversion to probable dementia. Acad Radiol 2008; 15:1089-98. [PMID: 18692749 DOI: 10.1016/j.acra.2008.04.008] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2008] [Revised: 03/25/2008] [Accepted: 04/01/2008] [Indexed: 11/24/2022]
Abstract
RATIONALE AND OBJECTIVES Mild cognitive impairment has been regarded as a pre-Alzheimer condition, but some patients do not develop dementia. The authors' objective was to determine whether findings from a combined use of H1 magnetic resonance spectroscopy (MRS), perfusion imaging (PI), and diffusion-weighted imaging (DWI) would predict conversion from amnesic mild cognitive impairment to dementia and to compare the diagnostic accuracy in discriminating patients with probable Alzheimer disease (AD), mixed dementia (MD), Lewy body dementia (LBD), pre-Alzheimer disease mild cognitive impairment (MCI), vascular MCI (VaMCI), and anxious or depression patients with cognitive impairment (DeMCI). MATERIALS AND METHODS A longitudinal cohort of 119 consecutive and incident subjects (73 women, 46 men; age 70+/-9.5 years) who fulfilled the criteria of amnesic MCI was followed for a mean period of 29 months. At baseline, a neuropsychological examination and standard blood test were performed, and different areas were examined by proton MRS, PI, and DWI. Among the group of patients considered to have AD, we also included patients with MD because these patients have a neurodegenerative component. RESULTS After the follow-up period, 54 patients were considered as converted to dementia (49 with AD; 5 with LBD), 28 patients as MCI, 22 patients as DeMCI, and 15 patients as VaMCI. We found that N-acetylaspartate (NAA)/creatine (Cr) ratios in posterior cingulated gyri (PCG) predict the conversion to probable AD with a sensitivity of 82% and specificity of 72%, and NAA/Cr ratios in the left occipital cortex (LOC) had a sensitivity of 78% and specificity of 69%. When we used spectroscopy in the PCG and LOC to differentiate the types of MCI and dementias, we found significance differences in NAA/Cr, NAA/myoinositol (mI), NAA/choline (Cho), mI/NAA, and Cho/Cr ratios. The apparent diffusion coefficient (ADC) values in the right hippocampus showed differences in patients with LBD and DeMCI (P=.003), LBD with MCI (P=0.48), and LBD and VaMCI (P=.009). CONCLUSIONS NAA/Cr ratios in PCG and LOC can predict the conversion from MCI to dementia with high sensitivity and specificity. MRS can differentiate AD from MCI, but cannot differentiate the types of MCI. DWI in the right hippocampus presents higher values of ADC in LBD and allows differentiating it from MCI.
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Siemonsen S, Finsterbusch J, Matschke J, Lorenzen A, Ding XQ, Fiehler J. Age-dependent normal values of T2* and T2' in brain parenchyma. AJNR Am J Neuroradiol 2008; 29:950-5. [PMID: 18272561 DOI: 10.3174/ajnr.a0951] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
BACKGROUND AND PURPOSE Physiologic age-related T2* and T2' values are required as reference for comparison with disease-related deviations. In our study, T2* and T2' values (T2 values as control) were determined with MR imaging in healthy subjects to determine standard values and investigate age-related changes. MATERIALS AND METHODS Data of 50 patients without intraparenchymal pathology and 10 acute stroke patients who underwent MR imaging including a T2 and T2* sequence with 3 echotimes were included. After calculation of T2*, T2', and T2 maps, the values of gray matter (GM) and white matter (WM) for each hemisphere were measured in 6 distinct regions of interest (ROIs). RESULTS There was a negative correlation between age and T2* values in the caudate nucleus (r = -0.34 Pearson correlation; P = .001) and lentiform nucleus (r = -0.67; P = .001) and a positive correlation in the occipital (r = 0.41; P = .001) and subcortical (r = 0.45; P = .001) WM. An age dependency for T2' values was only found for the caudate (r = -0.35; P = .001) and lentiform nucleus (r = -0.69; P = .001). T2' values in acute stroke were lower than normal in all patients with stroke. CONCLUSION Decrease in T2' and T2* values in GM and increase of T2* values in WM correlate with the progress of brain aging. Explanations for decreasing T2' and T2* values include iron deposition in the caudate and lentiform nucleus. In contrast to T2* values, there is no association of T2' values with the degree of leukoaraiosis. These age-dependent values can be used as a reference in neurovascular diseases and for the discussion of functional MR imaging data.
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Affiliation(s)
- S Siemonsen
- Department of Neuroradiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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Nagesh V, Chenevert TL, Tsien CI, Ross BD, Lawrence TS, Junck L, Cao Y. Quantitative characterization of hemodynamic properties and vasculature dysfunction of high-grade gliomas. NMR IN BIOMEDICINE 2007; 20:566-77. [PMID: 17221937 DOI: 10.1002/nbm.1118] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Aberrations in tumor and peritumoral vasculature may not be distinguishable by cerebral blood flow (CBF) or cerebral blood volume (CBV) alone. The relationships between CBF and CBV were examined to estimate vasculature-specific hemodynamic characteristics. Twenty glioma patients were studied with dynamic susceptibility T2*-weighted MRI [(dynamic contrast-enhanced magnetic resonance imaging (DSC-MRI)] before and during week 1 and 3 of radiotherapy (RT). CBF and CBV were calculated from DSC-MRI, and relationships between the two were evaluated: the physiological measure of mean transit time (MTT) = CBV/CBF; empirical fitting using the power law CBV = constant x (CBF)(beta). Three different tissue types were assessed: the Gd-enhancing tumor volume (GEV); non-enhanced abnormal tissue located beyond GEV but within the abnormal hyperintense region on FLAIR images (NEV); normal tissue in the hemisphere contralateral to the tumor (CNT). The effects of tissue types, CBV magnitudes (low, medium and high), before and during RT, on MTT and beta were analyzed by analysis of variance (ANOVA). The MTT and beta for the three tissue types were significantly different (p < 0.009). MTT increased from CNT (1.60 s) to NEV (1.93 s) to GEV (2.28 s) (p < 0.0005). beta was significantly greater in GEV (1.079) and NEV (1.070) than in CNT (1.025). Beta increased with increasing CBV magnitude while MTT was independent of CBV magnitude. There was a significant decrease in MTT of NEV and GEV during week 3 of RT compared with pre-RT values for all CBV magnitudes. There was a significant increase in beta during RT in the tumor and peritumor. Progressive abnormalities in vasculature and hemodynamic characteristics of the vascular bed were delineated, with significant disorder in the tumor but mild abnormality in peritumoral tissue.
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Affiliation(s)
- Vijaya Nagesh
- Department of Radiation Oncology, University of Michigan, Ann Arbor, MI 48109-0010, USA
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Hakyemez B, Yildirim N, Erdoğan C, Kocaeli H, Korfali E, Parlak M. Meningiomas with conventional MRI findings resembling intraaxial tumors: can perfusion-weighted MRI be helpful in differentiation? Neuroradiology 2006; 48:695-702. [PMID: 16896907 DOI: 10.1007/s00234-006-0115-y] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2005] [Accepted: 05/17/2006] [Indexed: 02/07/2023]
Abstract
INTRODUCTION To investigate the contribution of perfusion-weighted MRI to the differentiation of meningiomas with atypical conventional MRI findings from intraaxial tumors. METHODS We retrospectively analyzed 54 meningiomas, 12 glioblastomas and 13 solitary metastases. We detected 6 meningiomas with atypical features on conventional MRI resembling intraaxial tumors. The regional cerebral blood flow (rCBV) ratios of all tumors were calculated via perfusion-weighted MRI. The signal intensity-time curves were plotted and three different curve patterns were observed. The type 1 curve resembled normal brain parenchyma or the postenhancement part was minimally below the baseline, the type 2 curve was similar to the type 1 curve but with the postenhancement part above the baseline, and the type 3 curve had the postenhancement part below the baseline accompanied by widening of the curve. Student's t-test was used for statistical analysis. RESULTS On CBV images meningiomas were hypervascular and the mean rCBV ratio was 10.58+/-2.00. For glioblastomas and metastatic lesions, the rCBV ratios were 5.02+/-1.40 and 4.68+/-1.54, respectively. There was a statistically significant difference in rCBV ratios between meningiomas and glioblastomas and metastases (P<0.001). Only one of the meningiomas displayed a type 2 curve while five showed a type 3 curve. Glioblastomas and metastases displayed either a type 1 or a type 2 curve. None of the meningiomas showed a type 1 curve and none of the glioblastomas or metastases showed a type 3 curve. CONCLUSION Differentiating meningiomas with atypical conventional MRI findings from malignant intraaxial tumors can be difficult. Calculation of rCBV ratios and construction of signal intensity-time curves may contribute to the differentiation of meningiomas from intraaxial tumors.
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Affiliation(s)
- Bahattin Hakyemez
- Department of Radiology, Uludag University Medical School, Bursa, Turkey.
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Kielstein JT, Donnerstag F, Gasper S, Menne J, Kielstein A, Martens-Lobenhoffer J, Scalera F, Cooke JP, Fliser D, Bode-Böger SM. ADMA increases arterial stiffness and decreases cerebral blood flow in humans. Stroke 2006; 37:2024-9. [PMID: 16809568 DOI: 10.1161/01.str.0000231640.32543.11] [Citation(s) in RCA: 162] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND AND PURPOSE Preclinical studies have revealed that the endogenous nitric oxide synthase inhibitor, asymmetric dimethylarginine (ADMA), increases vascular tone in cerebral blood vessels. Marked elevations of ADMA blood levels were found in patients with diseases characterized by decreased cerebral perfusion, such as ischemic stroke. Arterial stiffness is an independent predictor of stroke and other adverse cardiovascular events. The aim of this study was to investigate the influence of a systemic subpressor dose of ADMA on arterial stiffness and cerebral perfusion in humans. METHODS Using a double-blind, vehicle-controlled study design, we allocated 20 healthy men in random order to infusion of either ADMA (0.10 mg ADMA/kg per min) or vehicle over a period of 40 minutes. Arterial stiffness was assessed noninvasively by pulse wave analysis. All volunteers underwent measurement of cerebral perfusion by dynamic contrast-enhanced perfusion magnetic resonance imaging of the brain. RESULTS Infusion of ADMA significantly decreased total cerebral perfusion by 15.1+/-4.5% (P=0.007), whereas blood flow in the vehicle group increased by 7.7+/-2.8% (P=0.02). ADMA also increased arterial stiffness as assessed by measurement of the augmentation index (-12.6+/-1.9 to -9.6+/-1.5, P=0.007). CONCLUSIONS Our results document for the first time that subpressor doses of ADMA increase vascular stiffness and decrease cerebral perfusion in healthy subjects. Thus, ADMA is an important endogenous modulator of cerebral vascular tone and may be involved in the pathogenesis of cerebrovascular disease.
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Affiliation(s)
- Jan T Kielstein
- Department of Nephrology, Medical School, Hannover, Germany.
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Abstract
Stroke is a devastating disease with a complex pathophysiology. It is a major cause of death and disability in North America. To fully characterize its extent and effects, one requires numerous specialized anatomical and functional MR techniques, specifically diffusion-weighted imaging, MR angiography, and perfusion-weighted imaging. The advent of 3.0 T clinical scanners has the potential to provide higher quality information in potentially less time compared with 1.5 T stroke-specific MR imaging protocols. This article gives a brief overview of stroke, presents the principles and clinical applications of the relevant MR techniques required for diagnostic stroke imaging at high field, and discusses the advantages, challenges, and limitations of 3.0 T imaging as they relate to stroke.
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Abstract
There is increasing interest in using diffusion-weighted (DWI) MR imaging and perfusion-weighted MR imaging (PWI) to assist clinical decision-making in the management of acute stroke patients. Larger PWI than DWI lesions have been speculated to represent potentially salvageable tissue that is at risk of infarction unless nutritive flow is restored and presence of these mismatches have been proposed as inclusion criteria for identifying patients most likely to benefit from therapeutic intervention. Understanding the technical aspects of PWI may improve comprehension of the capabilities and limitations of this technique.
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Affiliation(s)
- Ona Wu
- MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA 02129, USA.
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Wintermark M, Sesay M, Barbier E, Borbély K, Dillon WP, Eastwood JD, Glenn TC, Grandin CB, Pedraza S, Soustiel JF, Nariai T, Zaharchuk G, Caillé JM, Dousset V, Yonas H. Comparative overview of brain perfusion imaging techniques. J Neuroradiol 2006; 32:294-314. [PMID: 16424829 DOI: 10.1016/s0150-9861(05)83159-1] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Numerous imaging techniques have been developed and applied to evaluate brain hemodynamics. Among these are: Positron Emission Tomography (PET), Single Photon Emission Computed Tomography (SPECT), Xenon-enhanced Computed Tomography (XeCT), Dynamic Perfusion-computed Tomography (PCT), Magnetic Resonance Imaging Dynamic Susceptibility Contrast (DSC), Arterial Spin-Labeling (ASL), and Doppler Ultrasound. These techniques give similar information about brain hemodynamics in the form of parameters such as cerebral blood flow (CBF) or volume (CBV). All of them are used to characterize the same types of pathological conditions. However, each technique has its own advantages and drawbacks. This article addresses the main imaging techniques dedicated to brain hemodynamics. It represents a comparative overview, established by consensus among specialists of the various techniques. For clinicians, this paper should offers a clearer picture of the pros and cons of currently available brain perfusion imaging techniques, and assist them in choosing the proper method in every specific clinical setting.
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Affiliation(s)
- M Wintermark
- Department of Radiology, Neuroradiology Section, University of California, 505 Parnassus Avenue, Room L358, Box 0628, San Francisco, CA 94143-0628, USA.
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Weber MA, Risse F, Giesel FL, Schad LR, Kauczor HU, Essig M. [Perfusion measurement using the T2* contrast media dynamics in neuro-oncology. Physical basics and clinical applications]. Radiologe 2005; 45:618-32. [PMID: 15098092 DOI: 10.1007/s00117-004-1048-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Perfusion imaging in the central nervous system (CNS) is mostly performed using the first-pass dynamic susceptibility-weighted contrast-enhanced (DSC) MRI. The first-pass of a contrast bolus in brain tissue is monitored by a series of T2*-weighted MR images. The susceptibility effect of the paramagnetic contrast agent leads to a signal loss that can be converted, using the principles of the indicator dilution theory, into an increase of the contrast agent concentration. From these data, parameter maps of cerebral blood volume (CBV) and flow (CBF) can be derived. Regional CBF and CBV values can be obtained by region-of-interest analysis. This review article describes physical basics of DSC MRI and summarizes the literature of DSC MRI in neurooncological issues.Studies, all with relatively limited patient numbers, report that DSC MRI is useful in the preoperative diagnosis of gliomas, CNS-lymphomas, and solitary metastases, as well as in the differentiation of these neoplastic lesions from infections and tumor-like manifestations of demyelinating disease. Additionally, DSC MRI is suitable for determining glioma grade and regions of active tumor growth which should be the target of stereotactic biopsy. After therapy, DSC MRI helps better assessing the tumor response to therapy, residual tumor after therapy, and possible treatment failure and therapy-related complications, such as radiation necrosis. The preliminary results show that DSC MRI is a diagnostic tool depicting regional variations in microvasculature of normal and diseased brains.
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Affiliation(s)
- M-A Weber
- Abteilung Radiologie, Deutsches Krebsforschungszentrum, Heidelberg.
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Krishnan S, Talley BD, Slavin MJ, Doraiswamy PM, Petrella JR. Current Status of Functional MR Imaging, Perfusion-Weighted Imaging, and Diffusion-Tensor Imaging in Alzheimer's Disease Diagnosis and Research. Neuroimaging Clin N Am 2005; 15:853-68, xi. [PMID: 16443496 DOI: 10.1016/j.nic.2005.09.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Advanced MR techniques, such as functional MR imaging, perfusion-weighted imaging, and diffusion-tensor imaging, offer the capability of detecting early functional, hemodynamic, and microstructural alterations in Alzheimer's disease before gross anatomic alterations. Most studies of these emerging technologies are at the exploratory stage, with the purpose of increasing understanding of the underlying disease process and defining cross-sectional differences across various subject populations. Assessment of the diagnostic efficacy of these technologies in detecting early Alzheimer's disease in its preclinical and prodromal stages is ongoing.
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Affiliation(s)
- Sriyesh Krishnan
- Department of Radiology, Duke University Medical Center, Durham, NC 27710, USA
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Wintermark M, Sesay M, Barbier E, Borbély K, Dillon WP, Eastwood JD, Glenn TC, Grandin CB, Pedraza S, Soustiel JF, Nariai T, Zaharchuk G, Caillé JM, Dousset V, Yonas H. Comparative overview of brain perfusion imaging techniques. Stroke 2005; 36:e83-99. [PMID: 16100027 DOI: 10.1161/01.str.0000177884.72657.8b] [Citation(s) in RCA: 328] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Numerous imaging techniques have been developed and applied to evaluate brain hemodynamics. Among these are positron emission tomography, single photon emission computed tomography, Xenon-enhanced computed tomography, dynamic perfusion computed tomography, MRI dynamic susceptibility contrast, arterial spin labeling, and Doppler ultrasound. These techniques give similar information about brain hemodynamics in the form of parameters such as cerebral blood flow or cerebral blood volume. All of them are used to characterize the same types of pathological conditions. However, each technique has its own advantages and drawbacks. SUMMARY OF REVIEW This article addresses the main imaging techniques dedicated to brain hemodynamics. It represents a comparative overview established by consensus among specialists of the various techniques. CONCLUSIONS For clinicians, this article should offer a clearer picture of the pros and cons of currently available brain perfusion imaging techniques and assist them in choosing the proper method for every specific clinical setting.
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Affiliation(s)
- Max Wintermark
- Department of Radiology, University of California, 505 Parnassus Ave, San Francisco, CA 94143-0628, USA.
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Ibaraki M, Shimosegawa E, Toyoshima H, Ishigame K, Ito H, Takahashi K, Miura S, Kanno I. Effect of Regional Tracer Delay on CBF in Healthy Subjects Measured with Dynamic Susceptibility Contrast-Enhanced MRI: Comparison with 15O-PET. Magn Reson Med Sci 2005; 4:27-34. [PMID: 16127251 DOI: 10.2463/mrms.4.27] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PURPOSE Deconvolution based on truncated singular value decomposition (SVD deconvolution) is a promising method for measuring cerebral blood flow (CBF) with dynamic susceptibility contrast-enhanced magnetic resonance imaging (DSC-MRI), but it has proved extremely sensitive to tracer delay. The purpose of this study was to investigate the effect of regional tracer delay on CBF determined by SVD deconvolution (SVD-CBF). SVD-CBFs with and without correction for the delay were compared with CBF measured by positron emission tomography (PET-CBF), which is regarded as the gold standard for quantification of CBF. METHODS Perfusion MRI and PET were performed on seven healthy men. In the PET study, the CBF image was obtained with bolus injection of H2(15)O and continuous arterial sampling. In the DSC-MRI study with bolus injection of Gd-based contrast agent, dynamic perfusion data were obtained with a 1.5T scanner at 1-s intervals by means of gradient-echo echo-planar imaging. CBF was determined by the SVD deconvolution method with and without correction for the tracer delay. Region-of-interest measurements were obtained in the gray matter (cerebral cortex in the middle cerebral artery territory) and white matter (centrum semiovale). RESULTS Tracer delay was significantly longer in white matter than in gray matter (1.45+/-0.61 s vs. 0.59+/-0.35 s, P<0.01). Correction for the delay increased SVD-CBF in the white matter and consequently reduced the gray-to-white SVD-CBF ratio. The uncorrected gray-to-white SVD-CBF ratio was significantly larger than that of PET-CBF (3.33+/-0.66 vs. 2.54+/-0.49, P<0.01). However, the gray-to-white delay-corrected SVD-CBF ratio did not differ significantly from that of PET-CBF (2.83+/-0.31 vs. 2.54+/-0.49, P=0.10). CONCLUSION The tracer delay in DSC-MRI causes errors in CBF estimates, even in healthy persons, and therefore should be corrected for when delay-sensitive deconvolution, such as SVD deconvolution, is used.
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Affiliation(s)
- Masanobu Ibaraki
- Department of Radiology and Nuclear Medicine, Akita Research Institute of Brain and Blood Vessels, 6-10 Senshu-Kubota Machi, Akita 010-0874, Japan.
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