1
|
Mohammadi S, Ghaderi S. Post-COVID-19 conditions: a systematic review on advanced magnetic resonance neuroimaging findings. Neurol Sci 2024; 45:1815-1833. [PMID: 38421524 DOI: 10.1007/s10072-024-07427-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 02/23/2024] [Indexed: 03/02/2024]
Abstract
Post-COVID conditions (PCCs) cover a wide spectrum of lingering symptoms experienced by survivors of coronavirus disease 2019 (COVID-19). Neurological and neuropsychiatric sequelae are common in PCCs. Advanced magnetic resonance imaging (MRI) techniques can reveal subtle alterations in brain structure, function, and perfusion that underlie these sequelae. This systematic review aimed to synthesize findings from studies that used advanced MRI to characterize brain changes in individuals with PCCs. A detailed literature search was conducted in the PubMed and Scopus databases to identify relevant studies that used advanced MRI modalities, such as structural MRI (sMRI), diffusion tensor imaging (DTI), functional MRI (fMRI), and perfusion-weighted imaging (PWI), to evaluate brain changes in PCCs. Twenty-five studies met the inclusion criteria, comprising 1219 participants with PCCs. The most consistent findings from sMRI were reduced gray matter volume (GMV) and cortical thickness (CTh) in cortical and subcortical regions. DTI frequently reveals increased mean diffusivity (MD), radial diffusivity (RD), and decreased fractional anisotropy (FA) in white matter tracts (WMTs) such as the corpus callosum, corona radiata, and superior longitudinal fasciculus. fMRI demonstrated altered functional connectivity (FC) within the default mode, salience, frontoparietal, somatomotor, subcortical, and cerebellar networks. PWI showed decreased cerebral blood flow (CBF) in the frontotemporal area, thalamus, and basal ganglia. Advanced MRI shows changes in the brain networks and regions of the PCCs, which may cause neurological and neuropsychiatric problems. Multimodal neuroimaging may help understand brain-behavior relationships. Longitudinal studies are necessary to better understand the progression of these brain anomalies.
Collapse
Affiliation(s)
- Sana Mohammadi
- Department of Medical Sciences, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Sadegh Ghaderi
- Department of Neuroscience and Addiction Studies, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran.
| |
Collapse
|
2
|
Mohammadi S, Ghaderi S. Advanced magnetic resonance neuroimaging techniques: feasibility and applications in long or post-COVID-19 syndrome - a review. Ann Med Surg (Lond) 2024; 86:1584-1589. [PMID: 38463042 PMCID: PMC10923379 DOI: 10.1097/ms9.0000000000001808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 01/29/2024] [Indexed: 03/12/2024] Open
Abstract
Long-term or post-COVID-19 syndrome (PCS) is a condition that affects people infected with SARS‑CoV‑2, the virus that causes COVID-19. PCS is characterized by a wide range of persistent or new symptoms that last months after the initial infection, such as fatigue, shortness of breath, cognitive dysfunction, and pain. Advanced magnetic resonance (MR) neuroimaging techniques can provide valuable information on the structural and functional changes in the brain associated with PCS as well as potential biomarkers for diagnosis and prognosis. In this review, we discuss the feasibility and applications of various advanced MR neuroimaging techniques in PCS, including perfusion-weighted imaging (PWI), diffusion-weighted imaging (DWI), susceptibility-weighted imaging (SWI), functional MR imaging (fMRI), diffusion tensor imaging (DTI), and tractography. We summarize the current evidence on neuroimaging findings in PCS, the challenges and limitations of these techniques, and the future directions for research and clinical practice. Although still uncertain, advanced MRI techniques show promise for gaining insight into the pathophysiology and guiding the management of COVID-19 syndrome, pending larger validation studies.
Collapse
Affiliation(s)
- Sana Mohammadi
- Department of Medical Sciences, School of Medicine, Iran University of Medical Sciences
| | - Sadegh Ghaderi
- Department of Neuroscience and Addiction Studies, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| |
Collapse
|
3
|
Abreu VS, Tarrio J, Silva J, Almeida F, Pinto C, Freitas D, Filipe JP. Multiparametric analysis from dynamic susceptibility contrast-enhanced perfusion MRI to evaluate malignant brain tumors. J Neuroimaging 2024; 34:257-266. [PMID: 38173078 DOI: 10.1111/jon.13183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 12/14/2023] [Accepted: 12/14/2023] [Indexed: 01/05/2024] Open
Abstract
BACKGROUND AND PURPOSE Dynamic susceptibility contrast-enhanced (DSC) MR perfusion is a valuable technique for distinguishing brain tumors. Diagnostic potential of measurable parameters derived from preload leakage-corrected-DSC-MRI remains somewhat underexplored. This study aimed to evaluate these parameters for differentiating primary CNS lymphoma (PCNSL), glioblastoma, and metastasis. METHODS Thirty-nine patients with pathologically proven PCNSL (n = 14), glioblastoma (n = 14), and metastasis (n = 11) were analyzed. Five DSC parameters-relative CBV (rCBV), percentage of signal recovery (PSR), downward slope (DS), upward slope (US), and first-pass slope ratio-were derived from tumor-enhancing areas. Diagnostic performance was assessed using receiver operating characteristic curve analysis. RESULTS RCBV was higher in metastasis (4.58; interquartile range [IQR]: 2.54) and glioblastoma (3.98; IQR: 1.87), compared with PCNSL (1.46; IQR: 0.29; p = .00006 for both). rCBV better distinguished metastasis and glioblastoma from PCNSL, with an area under the curve (AUC) of 0.97 and 0.99, respectively. PSR was higher in PCNSL (88.11; IQR: 21.21) than metastases (58.30; IQR: 22.28; p = .0002), while glioblastoma (74.54; IQR: 21.23) presented almost significant trend-level differences compared to the others (p≈.05). AUCs were 0.79 (PCNSL vs. glioblastoma), 0.91 (PCNSL vs. metastasis), and 0.78 (glioblastoma vs. metastasis). DS and US parameters were statistically significant between glioblastoma (-109.92; IQR: 152.71 and 59.06; IQR: 52.87) and PCNSL (-47.36; IQR: 44.30 and 21.68; IQR: 16.85), presenting AUCs of 0.86 and 0.87. CONCLUSION Metastasis and glioblastoma can be better differentiated from PCNSL through rCBV. PSR demonstrated higher differential performance compared to the other parameters and seemed useful, allowing a proper distinction among all, particularly between metastasis and glioblastoma, where rCBV failed. Finally, DS and US were only helpful in differentiating glioblastoma from PCNSL.
Collapse
Affiliation(s)
- Vasco Sousa Abreu
- Neuroradiology Department, Centro Hospitalar Universitário do Porto, Porto, Portugal
| | - João Tarrio
- Neuroradiology Department, Centro Hospitalar Universitário do Porto, Porto, Portugal
| | - José Silva
- Neuroradiology Department, Centro Hospitalar Universitário do Porto, Porto, Portugal
| | - Francisco Almeida
- Neuroradiology Department, Centro Hospitalar Universitário do Porto, Porto, Portugal
| | - Catarina Pinto
- Neuroradiology Department, Centro Hospitalar Universitário do Porto, Porto, Portugal
| | - Davide Freitas
- Neuroradiology Department, Centro Hospitalar Universitário do Porto, Porto, Portugal
| | - João Pedro Filipe
- Neuroradiology Department, Centro Hospitalar Universitário do Porto, Porto, Portugal
| |
Collapse
|
4
|
Filss CP, Cramer J, Löher S, Lohmann P, Stoffels G, Stegmayr C, Kocher M, Heinzel A, Galldiks N, Wittsack HJ, Sabel M, Neumaier B, Scheins J, Shah NJ, Meyer PT, Mottaghy FM, Langen KJ. Assessment of Brain Tumour Perfusion Using Early-Phase 18F-FET PET: Comparison with Perfusion-Weighted MRI. Mol Imaging Biol 2024; 26:36-44. [PMID: 37848641 PMCID: PMC10827807 DOI: 10.1007/s11307-023-01861-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 09/10/2023] [Accepted: 09/19/2023] [Indexed: 10/19/2023]
Abstract
PURPOSE Morphological imaging using MRI is essential for brain tumour diagnostics. Dynamic susceptibility contrast (DSC) perfusion-weighted MRI (PWI), as well as amino acid PET, may provide additional information in ambiguous cases. Since PWI is often unavailable in patients referred for amino acid PET, we explored whether maps of relative cerebral blood volume (rCBV) in brain tumours can be extracted from the early phase of PET using O-(2-18F-fluoroethyl)-L-tyrosine (18F-FET). PROCEDURE Using a hybrid brain PET/MRI scanner, PWI and dynamic 18F-FET PET were performed in 33 patients with cerebral glioma and four patients with highly vascularized meningioma. The time interval from 0 to 2 min p.i. was selected to best reflect the blood pool phase in 18F-FET PET. For each patient, maps of MR-rCBV, early 18F-FET PET (0-2 min p.i.) and late 18F-FET PET (20-40 min p.i.) were generated and coregistered. Volumes of interest were placed on the tumour (VOI-TU) and normal-appearing brain (VOI-REF). The correlation between tumour-to-brain ratios (TBR) of the different parameters was analysed. In addition, three independent observers evaluated MR-rCBV and early 18F-FET maps (18F-FET-rCBV) for concordance in signal intensity, tumour extent and intratumoural distribution. RESULTS TBRs calculated from MR-rCBV and 18F-FET-rCBV showed a significant correlation (r = 0.89, p < 0.001), while there was no correlation between late 18F-FET PET and MR-rCBV (r = 0.24, p = 0.16) and 18F-FET-rCBV (r = 0.27, p = 0.11). Visual rating yielded widely agreeing findings or only minor differences between MR-rCBV maps and 18F-FET-rCBV maps in 93 % of the tumours (range of three independent raters 91-94%, kappa among raters 0.78-1.0). CONCLUSION Early 18F-FET maps (0-2 min p.i.) in gliomas provide similar information to MR-rCBV maps and may be helpful when PWI is not possible or available. Further studies in gliomas are needed to evaluate whether 18F-FET-rCBV provides the same clinical information as MR-rCBV.
Collapse
Affiliation(s)
- Christian P Filss
- Department of Nuclear Medicine, RWTH University Hospital, Aachen, Germany.
- Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5, INM-11), Forschungszentrum Jülich, Jülich, Germany.
- Center of Integrated Oncology (CIO), University of Aachen, Bonn, Cologne and Düsseldorf, Germany.
| | - Julian Cramer
- Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5, INM-11), Forschungszentrum Jülich, Jülich, Germany
- Faculty of Medical Engineering and Technomathematics, FH Aachen University of Applied Sciences, Campus Juelich, Jülich, Germany
| | - Saskia Löher
- Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5, INM-11), Forschungszentrum Jülich, Jülich, Germany
- Faculty of Medical Engineering and Technomathematics, FH Aachen University of Applied Sciences, Campus Juelich, Jülich, Germany
| | - Philipp Lohmann
- Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5, INM-11), Forschungszentrum Jülich, Jülich, Germany
| | - Gabriele Stoffels
- Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5, INM-11), Forschungszentrum Jülich, Jülich, Germany
| | - Carina Stegmayr
- Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5, INM-11), Forschungszentrum Jülich, Jülich, Germany
| | - Martin Kocher
- Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5, INM-11), Forschungszentrum Jülich, Jülich, Germany
- Center of Integrated Oncology (CIO), University of Aachen, Bonn, Cologne and Düsseldorf, Germany
- Department of Stereotactic and Functional Neurosurgery, Center for Neurosurgery, University Hospital Cologne, Cologne, Germany
| | - Alexander Heinzel
- Department of Nuclear Medicine, RWTH University Hospital, Aachen, Germany
- Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5, INM-11), Forschungszentrum Jülich, Jülich, Germany
- Center of Integrated Oncology (CIO), University of Aachen, Bonn, Cologne and Düsseldorf, Germany
- Department of Nuclear Medicine, University Hospital Halle (Saale), Halle (Saale), Germany
| | - Norbert Galldiks
- Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5, INM-11), Forschungszentrum Jülich, Jülich, Germany
- Center of Integrated Oncology (CIO), University of Aachen, Bonn, Cologne and Düsseldorf, Germany
- Department of Neurology, University Hospital Cologne, Cologne, Germany
| | - Hans J Wittsack
- Department of Diagnostic and Interventional Radiology, Medical Faculty, University of Düsseldorf, Düsseldorf, Germany
| | - Michael Sabel
- Center of Integrated Oncology (CIO), University of Aachen, Bonn, Cologne and Düsseldorf, Germany
- Department of Neurosurgery, University Hospital Düsseldorf, Düsseldorf, Germany
| | - Bernd Neumaier
- Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5, INM-11), Forschungszentrum Jülich, Jülich, Germany
- Institute of Radiochemistry and Experimental Molecular Imaging, University Hospital Cologne, Cologne, Germany
| | - Jürgen Scheins
- Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5, INM-11), Forschungszentrum Jülich, Jülich, Germany
| | - N Jon Shah
- Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5, INM-11), Forschungszentrum Jülich, Jülich, Germany
- JARA - BRAIN - Translational Medicine, RWTH Aachen University, Aachen, Germany
- Department of Neurology, RWTH Aachen University Hospital, Aachen, Germany
| | - Philipp T Meyer
- Department of Nuclear Medicine, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Felix M Mottaghy
- Department of Nuclear Medicine, RWTH University Hospital, Aachen, Germany
- Center of Integrated Oncology (CIO), University of Aachen, Bonn, Cologne and Düsseldorf, Germany
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center (MUMC+), Maastricht, Netherlands
| | - Karl-Josef Langen
- Department of Nuclear Medicine, RWTH University Hospital, Aachen, Germany
- Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5, INM-11), Forschungszentrum Jülich, Jülich, Germany
- Center of Integrated Oncology (CIO), University of Aachen, Bonn, Cologne and Düsseldorf, Germany
- JARA - BRAIN - Translational Medicine, RWTH Aachen University, Aachen, Germany
| |
Collapse
|
5
|
Brownsett SLE, Mascelloni M, Gowlett G, McMahon KL, de Zubicaray GI. Neighing dogs: Semantic context effects of environmental sounds in spoken word production - a replication and extension. Q J Exp Psychol (Hove) 2023; 76:1990-2000. [PMID: 36301012 DOI: 10.1177/17470218221137007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/23/2023]
Abstract
Semantic context effects are well established using both words and pictures as stimuli. One such effect, semantic interference, is observed in naming latencies when a categorically related distractor word or picture is presented together with a target picture (e.g., dog-LION). Recently, this effect has also been shown to occur when an environmental sound (e.g., a dog barking) is presented as an auditory distractor during picture naming and when a distractor picture is presented with a target sound for naming. The purpose of the current study was twofold: (1) to replicate the semantic interference effect in the picture-sound interference (PSI) paradigm and (2) determine whether a semantic interference effect is also observable when distractor words are presented with environmental sounds as target auditory objects for naming, using a novel sound-word interference (SWI) paradigm. We replicated the semantic interference effect in Experiment 1 with environmental sound distractors. Experiment 2 demonstrated significant semantic interference during an SWI paradigm for the first time. We discuss the implications of these results for our understanding of the origin and locus of the semantic interference effect according to current theories of lexical selection.
Collapse
Affiliation(s)
- Sonia LE Brownsett
- School of Health and Rehabilitation Sciences, The University of Queensland, St Lucia, QLD, Australia
- NHMRC Centre of Research Excellence in Aphasia Recovery and Rehabilitation, Melbourne, VIC, Australia
| | - Matteo Mascelloni
- School of Psychology and Counselling, Faculty of Health, Queensland University of Technology, Brisbane, QLD, Australia
| | - Georgia Gowlett
- School of Psychology and Counselling, Faculty of Health, Queensland University of Technology, Brisbane, QLD, Australia
| | - Katie L McMahon
- School of Clinical Sciences and Centre for Biomedical Technologies, Queensland University of Technology, Brisbane, QLD, Australia
- Herston Imaging Research Facility, Royal Brisbane & Women's Hospital, Herston, QLD, Australia
| | - Greig I de Zubicaray
- School of Psychology and Counselling, Faculty of Health, Queensland University of Technology, Brisbane, QLD, Australia
| |
Collapse
|
6
|
Guarnera A, Romano A, Moltoni G, Ius T, Palizzi S, Romano A, Bagatto D, Minniti G, Bozzao A. The Role of Advanced MRI Sequences in the Diagnosis and Follow-Up of Adult Brainstem Gliomas: A Neuroradiological Review. Tomography 2023; 9:1526-1537. [PMID: 37624115 PMCID: PMC10457939 DOI: 10.3390/tomography9040122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 08/08/2023] [Accepted: 08/09/2023] [Indexed: 08/26/2023] Open
Abstract
The 2021 WHO (World Health Organization) classification of brain tumors incorporated the rapid advances in the molecular, genetic, and pathogenesis understanding of brain tumor pathogenesis, behavior, and treatment response. It revolutionized brain tumor classification by placing great emphasis on molecular types and completely splitting adult-type and pediatric-type diffuse gliomas. Brainstem gliomas (BSGs) are the leading primary tumors of the brainstem, although they are quite uncommon in adults compared with the pediatric population, representing less than 2% of adult gliomas. Surgery is not always the treatment of choice since resection is rarely feasible and does not improve overall survival, and biopsies are not generally performed since the location is treacherous. Therefore, MRI (Magnetic Resonance Imaging) without and with gadolinium administration represents the optimal noninvasive radiological technique to suggest brainstem gliomas diagnosis, plan a multidisciplinary treatment and for follow-up evaluations. The MRI protocol encompasses morphological sequences as well as functional and advanced sequences, such as DWI/ADC (Diffusion-Weighted Imaging/Apparent Diffusion Coefficient), DTI (Diffusion Tensor Imaging), PWI (Perfusion-Weighted Imaging), and MRS (Magnetic Resonance Spectroscopy), which improve the accuracy of the diagnosis of BSGs by adding substantial information regarding the cellularity, the infiltrative behavior toward the v fiber tracts, the vascularity, and the molecular changes. Brainstem gliomas have been divided into four categories on the basis of their MRI radiological appearance, including diffuse intrinsic low-grade gliomas, enhancing malignant gliomas, localized tectal gliomas, and other forms. The aim of our review is to provide insight into the role of advanced MRI sequences in the diagnosis and follow-up of adult brainstem gliomas.
Collapse
Affiliation(s)
- Alessia Guarnera
- Neuroradiology Unit, NESMOS Department Sant’Andrea Hospital, La Sapienza University of Rome, Via di Grottarossa, 1035-1039, 00189 Rome, Italy; (A.R.); (G.M.); (S.P.); (A.R.); (A.B.)
- Neuroradiology Unit, Imaging Department, Bambino Gesù Children’s Hospital, Piazza Sant’Onofrio 4, 00165 Rome, Italy
| | - Andrea Romano
- Neuroradiology Unit, NESMOS Department Sant’Andrea Hospital, La Sapienza University of Rome, Via di Grottarossa, 1035-1039, 00189 Rome, Italy; (A.R.); (G.M.); (S.P.); (A.R.); (A.B.)
| | - Giulia Moltoni
- Neuroradiology Unit, NESMOS Department Sant’Andrea Hospital, La Sapienza University of Rome, Via di Grottarossa, 1035-1039, 00189 Rome, Italy; (A.R.); (G.M.); (S.P.); (A.R.); (A.B.)
- Neuroradiology Unit, Imaging Department, Bambino Gesù Children’s Hospital, Piazza Sant’Onofrio 4, 00165 Rome, Italy
| | - Tamara Ius
- Neurosurgery Unit, Head-Neck and NeuroScience Department, University Hospital of Udine, Piazzale Santa Maria della Misericordia 15, 33100 Udine, Italy;
| | - Serena Palizzi
- Neuroradiology Unit, NESMOS Department Sant’Andrea Hospital, La Sapienza University of Rome, Via di Grottarossa, 1035-1039, 00189 Rome, Italy; (A.R.); (G.M.); (S.P.); (A.R.); (A.B.)
| | - Allegra Romano
- Neuroradiology Unit, NESMOS Department Sant’Andrea Hospital, La Sapienza University of Rome, Via di Grottarossa, 1035-1039, 00189 Rome, Italy; (A.R.); (G.M.); (S.P.); (A.R.); (A.B.)
| | - Daniele Bagatto
- Neuroradiology Unit, Department of Diagnostic Imaging, University Hospital of Udine, Piazzale Santa Maria della Misericordia 15, 33100 Udine, Italy;
| | - Giuseppe Minniti
- Department of Radiological Sciences, Oncology and Anatomical Pathology, Division of Radiotherapy, La Sapienza University of Rome, 00161 Rome, Italy;
- IRCCS Neuromed, 86077 Pozzilli, Italy
| | - Alessandro Bozzao
- Neuroradiology Unit, NESMOS Department Sant’Andrea Hospital, La Sapienza University of Rome, Via di Grottarossa, 1035-1039, 00189 Rome, Italy; (A.R.); (G.M.); (S.P.); (A.R.); (A.B.)
| |
Collapse
|
7
|
Werner JM, Wollring MM, Tscherpel C, Rosen EK, Werr L, Stetter I, Rueß D, Ruge MI, Brunn A, Al Shughri A, Kabbasch C, Fink GR, Langen KJ, Galldiks N. Multimodal imaging findings in patients with glioblastoma with extensive coagulative necrosis related to regorafenib. Neuro Oncol 2023; 25:1193-1195. [PMID: 36960770 PMCID: PMC10237410 DOI: 10.1093/neuonc/noad051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2023] Open
Affiliation(s)
- Jan-Michael Werner
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Michael M Wollring
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
- Institute of Neuroscience and Medicine (INM-3, -4), Research Center Juelich, Juelich, Germany
| | - Caroline Tscherpel
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
- Institute of Neuroscience and Medicine (INM-3, -4), Research Center Juelich, Juelich, Germany
| | - Elena K Rosen
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Lisa Werr
- Department of Experimental Pediatric Oncology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Isabelle Stetter
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Daniel Rueß
- Department of Stereotactic and Functional Neurosurgery, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne,Germany
| | - Maximilian I Ruge
- Department of Stereotactic and Functional Neurosurgery, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne,Germany
| | - Anna Brunn
- Institute of Neuropathology, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Abdulkader Al Shughri
- Institute of Neuropathology, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Christoph Kabbasch
- Institure of Radiology, Division of Neuroradiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne,Germany
| | - Gereon R Fink
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
- Institute of Neuroscience and Medicine (INM-3, -4), Research Center Juelich, Juelich, Germany
| | - Karl-Josef Langen
- Institute of Neuroscience and Medicine (INM-3, -4), Research Center Juelich, Juelich, Germany
- Department of Nuclear Medicine, University Hospital Aachen, Aachen, Germany
| | - Norbert Galldiks
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
- Institute of Neuroscience and Medicine (INM-3, -4), Research Center Juelich, Juelich, Germany
- Center for Integrated Oncology (CIO), Universities of Aachen, Bonn, Cologne, and Duesseldorf, Cologne, Germany
| |
Collapse
|
8
|
Wu R, Schiller NO. Gender Congruency Effects in Spanish: Behavioral Evidence from Noun Phrase Production. Brain Sci 2023; 13:brainsci13040696. [PMID: 37190661 DOI: 10.3390/brainsci13040696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 04/15/2023] [Accepted: 04/17/2023] [Indexed: 05/17/2023] Open
Abstract
Grammatical gender as a lexico-syntactic feature has been well explored, and the gender congruency effect has been observed in many languages (e.g., Dutch, German, Croatian, Czech, etc.). Yet, so far, this effect has not been found in Romance languages such as Italian, French, and Spanish. It has been argued that the absence of the effect in Romance languages is due the fact that the gender-marking definite article is not exclusively dependent on the grammatical gender of the head noun, but also on its onset phonology (e.g., lo zucchero is 'the sugar' in Italian, not il zucchero, il being the default masculine determiner in Italian). For Spanish, this argument has also been made because feminine words starting with a stressed /a/ take the masculine article (e.g., el água is 'the water', not la água). However, the number of words belonging to that set is rather small in Spanish, and it may be questionable whether or not this feature can be taken as an argument for the absence of a gender congruency effect in Spanish. In this study, we investigated the gender congruency effect in native Spanish noun phrase production. We measured 30 native Spanish speakers' naming latencies in four conditions via the picture-word interference paradigm by manipulating gender congruency (i.e., gender-congruent vs. gender-incongruent) and semantic relatedness (i.e., semantically related vs. semantically unrelated). The results revealed significantly longer naming latencies in gender-incongruent and semantically related conditions compared to gender-congruent and semantically unrelated conditions. This result suggests that grammatical gender as a lexico-syntactic feature in Spanish is used to competitively select determiners in native Spanish speakers' noun phrases. Our findings provide an important behavioral piece of evidence for the gender congruency effect in Romance languages.
Collapse
Affiliation(s)
- Ruixue Wu
- Leiden University Centre for Linguistics (LUCL), Leiden University, Reuvensplaats 3, 2311 BE Leiden, The Netherlands
| | - Niels O Schiller
- Leiden University Centre for Linguistics (LUCL), Leiden University, Reuvensplaats 3, 2311 BE Leiden, The Netherlands
- Leiden Institute for Brain and Cognition (LIBC), Leiden University, LUMC, Postzone C2-S, P.O. Box 9600, 2300 RC Leiden, The Netherlands
| |
Collapse
|
9
|
Nazari-Farsani S, Yu Y, Duarte Armindo R, Lansberg M, Liebeskind DS, Albers G, Christensen S, Levin CS, Zaharchuk G. Predicting final ischemic stroke lesions from initial diffusion-weighted images using a deep neural network. Neuroimage Clin 2023; 37:103278. [PMID: 36481696 PMCID: PMC9727698 DOI: 10.1016/j.nicl.2022.103278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 11/20/2022] [Accepted: 11/30/2022] [Indexed: 12/03/2022]
Abstract
BACKGROUND For prognosis of stroke, measurement of the diffusion-perfusion mismatch is a common practice for estimating tissue at risk of infarction in the absence of timely reperfusion. However, perfusion-weighted imaging (PWI) adds time and expense to the acute stroke imaging workup. We explored whether a deep convolutional neural network (DCNN) model trained with diffusion-weighted imaging obtained at admission could predict final infarct volume and location in acute stroke patients. METHODS In 445 patients, we trained and validated an attention-gated (AG) DCNN to predict final infarcts as delineated on follow-up studies obtained 3 to 7 days after stroke. The input channels consisted of MR diffusion-weighted imaging (DWI), apparent diffusion coefficients (ADC) maps, and thresholded ADC maps with values less than 620 × 10-6 mm2/s, while the output was a voxel-by-voxel probability map of tissue infarction. We evaluated performance of the model using the area under the receiver-operator characteristic curve (AUC), the Dice similarity coefficient (DSC), absolute lesion volume error, and the concordance correlation coefficient (ρc) of the predicted and true infarct volumes. RESULTS The model obtained a median AUC of 0.91 (IQR: 0.84-0.96). After thresholding at an infarction probability of 0.5, the median sensitivity and specificity were 0.60 (IQR: 0.16-0.84) and 0.97 (IQR: 0.93-0.99), respectively, while the median DSC and absolute volume error were 0.50 (IQR: 0.17-0.66) and 27 ml (IQR: 7-60 ml), respectively. The model's predicted lesion volumes showed high correlation with ground truth volumes (ρc = 0.73, p < 0.01). CONCLUSION An AG-DCNN using diffusion information alone upon admission was able to predict infarct volumes at 3-7 days after stroke onset with comparable accuracy to models that consider both DWI and PWI. This may enable treatment decisions to be made with shorter stroke imaging protocols.
Collapse
Affiliation(s)
| | - Yannan Yu
- Department of Radiology, Stanford University, CA, USA; Internal Medicine Department, University of Massachusetts Memorial Medical Center, University of Massachusetts, Boston, USA
| | - Rui Duarte Armindo
- Department of Radiology, Stanford University, CA, USA; Department of Neuroradiology, Hospital Beatriz Ângelo, Loures, Lisbon, Portugal
| | | | - David S Liebeskind
- Department of Neurology, University of California Los Angeles, Los Angeles, CA, USA
| | | | | | - Craig S Levin
- Department of Radiology, Stanford University, CA, USA
| | | |
Collapse
|
10
|
Nguemeni Tiako MJ, Wages JE, Perry SP. Black Medical Students' Sense of Belonging and Confidence in Scholastic Abilities at Historically Black vs Predominantly White Medical Schools: a Prospective Study. J Gen Intern Med 2023; 38:122-124. [PMID: 35840780 PMCID: PMC9849616 DOI: 10.1007/s11606-022-07716-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 06/17/2022] [Indexed: 01/22/2023]
Affiliation(s)
- Max Jordan Nguemeni Tiako
- Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA.
- Harvard Medical School, Boston, MA, USA.
| | - James E Wages
- Department of Psychology and Counseling, University of Central Arkansas, Conway, AR, USA
| | - Sylvia P Perry
- Department of Psychology, Northwestern University, Evanston, IL, USA
- Institute for Policy Research, Northwestern University, Evanston, IL, USA
- Department of Medical Social Sciences, Northwestern University, Chicago, IL, USA
| |
Collapse
|
11
|
Zhang Y, Song S, Li Z, Huang B, Geng Y, Zhang L. The Application of Software "Rapid Processing of Perfusion and Diffusion" in Acute Ischemic Stroke. Brain Sci 2022; 12:1451. [PMID: 36358379 PMCID: PMC9688896 DOI: 10.3390/brainsci12111451] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 10/20/2022] [Accepted: 10/20/2022] [Indexed: 08/30/2023] Open
Abstract
In the event of an acute ischemic stroke, saving the penumbra is the most important aspect of early treatment. The rapid and accurate identification of ischemic penumbra plays a key role in its comprehensive treatment. At present, the identification method and evaluation standard of ischemic penumbra have not been unified. Numerous pieces of software identifying ischemic penumbra have been developed, such as rapid processing of perfusion and diffusion (RAPID), Sphere, Vitrea, and computed tomography perfusion+ (CTP+). The RAPID software, analyzing and integrating multi-mode image data (mainly based on perfusion weighted imaging (PWI) or computed tomography perfusion (CTP) images, shows good performance in identifying ischemic penumbra and has been utilized for the assessment of ischemic penumbra in many ischemic stroke clinical studies, achieving good outcomes and promoting the transition from "time window" to "tissue window" in the treatment of early stage AIS. To obtain a comprehensive understanding of the RAPID software and its accuracy in evaluating ischemic penumbra, this paper reviews the background and development of the RAPID software, summarizes the published acute cerebral infarction trials using the RAPID software, generalizes the threshold parameters in different time windows, and further discusses its application and limitations.
Collapse
Affiliation(s)
- Yudi Zhang
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Shuang Song
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Zhenzhong Li
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Boyuan Huang
- Department of Radiology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Yanlu Geng
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
- Department of Neurology, Central Hospital of Qinghe County, Xingtai 054800, China
| | - Lihong Zhang
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| |
Collapse
|
12
|
Lee H, Jung K, Kang DW, Kim N. Fully Automated and Real-Time Volumetric Measurement of Infarct Core and Penumbra in Diffusion- and Perfusion-Weighted MRI of Patients with Hyper-Acute Stroke. J Digit Imaging 2021; 33:262-272. [PMID: 31267445 DOI: 10.1007/s10278-019-00222-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Multimodal magnetic resonance imaging (MRI) has emerged as a promising tool for diagnosing ischemic stroke and for determining treatment strategies in the acute phase. The detection and quantification of the penumbra and the infarct core regions aid the assessment of the potential risks and benefits of thrombolysis by providing information on salvageable tissue or ischemic lesion age. In this study, we proposed a fully automated and real-time algorithm to compute parameter maps of perfusion-weighted images (PWIs) and to identify an infarct core from diffusion-weighted images (DWIs). DWI and PWI were obtained using a 1.5 Tesla MRI scanner for 15 patients with acute ischemic stroke. Parameter maps of PWI were computed using restricted gamma-variate curve fitting and Fourier-based deconvolution. The ischemic penumbra was identified using time-to-maximum (Tmax) > 6 s as the mutual optimal threshold, while the infarct core was segmented using an adaptive thresholding on DWI. When the penumbra on PWI was compared with that generated using commercial software Pearson's linear correlation coefficient between penumbra volumes was 0.601 (p = 0.030), and the Dice coefficient was 0.51 ± 0.15. The infarct core on DWI was compared with the manually segmented gold standard. Dice coefficient between the manually drawn and automated segmented infarct cores was 0.62 ± 0.18. The processing times for PWI and DWI were 222.9 ± 16.4 and 53.4 ± 4.8 s, respectively. In conclusion, we demonstrate a fully automated and real-time algorithm to segment the penumbra and the infarct core regions based on PWI and DWI.
Collapse
Affiliation(s)
- Hyunna Lee
- Health Innovation Big Data Center, Asan Institute for Life Science, Asan Medical Center, Seoul, 05505, South Korea
| | - Kyesam Jung
- Institute of Neuroscience and Medicine - Brain & Behaviour (INM-7), Research Centre Jülich, Jülich, 52425, Germany
| | - Dong-Wha Kang
- Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, 05505, South Korea
| | - Namkug Kim
- Department of Convergence Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, 05505, South Korea.
- Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, 05505, South Korea.
| |
Collapse
|
13
|
Mascelloni M, McMahon KL, Piai V, Kleinman D, de Zubicaray G. Mediated phonological-semantic priming in spoken word production: Evidence for cascaded processing from picture-word interference. Q J Exp Psychol (Hove) 2021; 74:1284-1294. [PMID: 33818205 DOI: 10.1177/17470218211010591] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The cognitive architecture that allows humans to retrieve words from the mental lexicon has been investigated for decades. While there is consensus regarding a two-step architecture involving lexical-conceptual and phonological word-form levels of processing, accounts of how activation spreads between them (e.g., in a serial, cascaded, or interactive fashion) remain contentious. In addition, production models differ with respect to whether selection occurs at lexical or postlexical levels. The purpose of this study was to examine whether mediated phonological-semantic relations (e.g., drip is phonologically related to drill that is semantically related to hammer) influence production in adults as predicted by models implementing cascaded processing and feedback between levels. Two experiments using the picture-word interference (PWI) paradigm were conducted using auditory (Exp. 1) and written (Exp. 2) distractors. We hypothesised that a mediated semantic interference effect would be observable in the former with the involvement of both spoken word production and recognition, and in the latter if lexical representations are shared between written and spoken words in English, as assumed by some production accounts. Furthermore, we hypothesised a mediated semantic interference effect would be inconsistent with a postlexical selection account as the distractors do not constitute a relevant response for the target picture (e.g., drip-HAMMER). We observed mediated semantic interference only from auditory distractors, while observing the standard semantic interference effect from both auditory and written distractors. The current findings represent the first chronometric evidence involving spoken word production and recognition in support of cascaded processing during lexical retrieval in adults and present a significant challenge for the postlexical selection account.
Collapse
Affiliation(s)
- Matteo Mascelloni
- School of Psychology and Counselling, Faculty of Health, Queensland University of Technology, Kelvin Grove, QLD, Australia
| | - Katie L McMahon
- School of Psychology and Counselling, Faculty of Health, Queensland University of Technology, Kelvin Grove, QLD, Australia.,School of Clinical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, QLD, Australia
| | - Vitória Piai
- Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Cognition, Radboud University, Nijmegen, The Netherlands.,Department of Medical Psychology, Donders Centre for Medical Neuroscience, Radboud University Medical Centre, Nijmegen, The Netherlands
| | | | - Greig de Zubicaray
- School of Psychology and Counselling, Faculty of Health, Queensland University of Technology, Kelvin Grove, QLD, Australia
| |
Collapse
|
14
|
Garcia-Esperon C, Raposo N, Seners P, Spratt N, Parsons M, Olivot JM. Role of neuroimaging before reperfusion therapy. Part 1 - IV thrombolysis - Review. Rev Neurol (Paris) 2021:S0035-3787(20)30754-2. [PMID: 33455833 DOI: 10.1016/j.neurol.2020.10.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 09/25/2020] [Accepted: 10/05/2020] [Indexed: 11/22/2022]
Abstract
This review paper summarises the yield of the different imaging modalities in the evaluation of patients for IV thrombolysis. Non-contrast CT and CTA or brain MRI combined with MRA are the recommended sequences for the evaluation of patients within the 4.5 hours time window. Multimodal MRI (DWI/PWI), and more recently, CT perfusion, offer reliable surrogate of salvageable penumbra, the target mismatch, which is now currently used as selection criteria for revascularisation treatment in an extended time window. Those sequences may also help the physician for the management of other limited cases when the diagnosis of acute ischemic stroke is difficult. Another approach the DWI/FLAIR mismatch has been proposed to identify among wake-up stroke patients those who have been experiencing an acute ischemic stroke evolving from less than 4.5hrs. Other biomarkers, such as the clot imaging on MRI and CT, help to predict the recanalisation rate after IVT, while the impact of the presence microbleeds on MRI remains to be determined.
Collapse
|
15
|
Steidl E, Langen KJ, Hmeidan SA, Polomac N, Filss CP, Galldiks N, Lohmann P, Keil F, Filipski K, Mottaghy FM, Shah NJ, Steinbach JP, Hattingen E, Maurer GD. Sequential implementation of DSC-MR perfusion and dynamic [ 18F]FET PET allows efficient differentiation of glioma progression from treatment-related changes. Eur J Nucl Med Mol Imaging 2021; 48:1956-65. [PMID: 33241456 DOI: 10.1007/s00259-020-05114-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 11/08/2020] [Indexed: 11/21/2022]
Abstract
Purpose Perfusion-weighted MRI (PWI) and O-(2-[18F]fluoroethyl-)-l-tyrosine ([18F]FET) PET are both applied to discriminate tumor progression (TP) from treatment-related changes (TRC) in patients with suspected recurrent glioma. While the combination of both methods has been reported to improve the diagnostic accuracy, the performance of a sequential implementation has not been further investigated. Therefore, we retrospectively analyzed the diagnostic value of consecutive PWI and [18F]FET PET. Methods We evaluated 104 patients with WHO grade II–IV glioma and suspected TP on conventional MRI using PWI and dynamic [18F]FET PET. Leakage corrected maximum relative cerebral blood volumes (rCBVmax) were obtained from dynamic susceptibility contrast PWI. Furthermore, we calculated static (i.e., maximum tumor to brain ratios; TBRmax) and dynamic [18F]FET PET parameters (i.e., Slope). Definitive diagnoses were based on histopathology (n = 42) or clinico-radiological follow-up (n = 62). The diagnostic performance of PWI and [18F]FET PET parameters to differentiate TP from TRC was evaluated by analyzing receiver operating characteristic and area under the curve (AUC). Results Across all patients, the differentiation of TP from TRC using rCBVmax or [18F]FET PET parameters was moderate (AUC = 0.69–0.75; p < 0.01). A rCBVmax cutoff > 2.85 had a positive predictive value for TP of 100%, enabling a correct TP diagnosis in 44 patients. In the remaining 60 patients, combined static and dynamic [18F]FET PET parameters (TBRmax, Slope) correctly discriminated TP and TRC in a significant 78% of patients, increasing the overall accuracy to 87%. A subgroup analysis of isocitrate dehydrogenase (IDH) mutant tumors indicated a superior performance of PWI to [18F]FET PET (AUC = 0.8/< 0.62, p < 0.01/≥ 0.3). Conclusion While marked hyperperfusion on PWI indicated TP, [18F]FET PET proved beneficial to discriminate TP from TRC when PWI remained inconclusive. Thus, our results highlight the clinical value of sequential use of PWI and [18F]FET PET, allowing an economical use of diagnostic methods. The impact of an IDH mutation needs further investigation. Supplementary Information The online version contains supplementary material available at 10.1007/s00259-020-05114-0.
Collapse
|
16
|
Hartmann A, Scholz VB, Lautenschläger IE. MRI perfusion analysis using freeware, standard imaging software. BMC Vet Res 2020; 16:141. [PMID: 32423403 DOI: 10.1186/s12917-020-02352-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Accepted: 04/29/2020] [Indexed: 11/10/2022] Open
Abstract
Background Perfusion-weighted imaging is only scarcely used in veterinary medicine. The exact reasons are unclear. One reason might be the typically high costs of the software packages for image analysis. In addition, a great variability concerning available programs makes it hard to compare results between different studies. Moreover, these algorithms are tuned for their usage in human medicine and often difficult to adapt to veterinary studies. In order to address these issues, our aim is to deliver a free open source package for calculating quantitative perfusion parameters. We develop an “R package” calculating mean transit time, cerebral blood flow and cerebral blood volume from data obtained with freely imaging software (OsiriX Light®). We hope that the free availability, in combination with the fact that the underlying algorithm is open and adaptable, makes it easier for scientists in veterinary medicine to use, compare and adapt perfusion-weighted imaging analysis. In order to demonstrate the usage of our software package, we reviewed previously acquired perfusion-weighted images from a group of eight purpose-breed healthy beagle dogs and twelve client-owned dogs with idiopathic epilepsy. In order to obtain the data needed for our algorithm, the following steps were performed: First, regions of interest (ROI) were drawn around different, previously reported, brain regions and the middle cerebral artery. Second, a ROI enhancement curve was generated for each ROI using a freely available PlugIn. Third, the signal intensity curves were exported as a comma-separated-value file. These files constitute the input to our software package, which then calculates the PWI parameters. Results We used our software package to re-assess perfusion weighted images from two previous studies. The clinical results were similar, showing a significant increase in the mean transit time and a significant decrease in cerebral blood flow for diseased dogs. Conclusion We provide an “R package” for computing the main perfusion parameters from measurements taken with standard imaging software and describe in detail how to obtain these measurements. We hope that our contribution enables users in veterinary medicine to easily obtain perfusion parameters using standard Open Source software in a standard, adaptable and comparable way.
Collapse
|
17
|
Creyaufmüller M, Heim S, Habel U, Mühlhaus J. The influence of semantic associations on sentence production in schizophrenia: an fMRI study. Eur Arch Psychiatry Clin Neurosci 2020; 270:359-372. [PMID: 30094543 DOI: 10.1007/s00406-018-0936-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 07/30/2018] [Indexed: 11/24/2022]
Abstract
One of the most prominent symptoms of schizophrenia is thought disorder, which manifests itself in language production difficulties. In patients with thought disorders the associations are loosened and sentence production is impaired. The determining behavioral and neural mechanisms of sentence production are still an important subject of recent research and have not yet been fully understood. The aim of the current study was to examine the influence of associative relations and distractor modalities on sentence production in healthy participants and participants with schizophrenia. Therefore, reaction times and neural activation of 12 healthy subjects and 13 subjects with schizophrenia were compared in an adapted picture word interference paradigm (PWI). No significant group differences were found, neither on the behavioral nor on the neural level. On the behavioral level, for the entire group incremental sentence processing was found, i.e. processing of the second noun only starts after the first noun was processed. At the neural level, activation was discovered in the bilateral caudate nuclei and the cerebellum. Those activations could be related to response enhancement and suppression as well as to the modulation of cognitive processes.
Collapse
Affiliation(s)
- Maike Creyaufmüller
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Pauwelsstrasse 30, 52074, Aachen, Germany
| | - Stefan Heim
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Pauwelsstrasse 30, 52074, Aachen, Germany. .,JARA Translational Brain Medicine, Aachen, Germany. .,AG Neuroanatomy of Language, Institute of Neurosciences and Medicine (INM-1), Research Centre Jülich, Leo-Brand-Straße 5, 52428, Jülich, Germany.
| | - Ute Habel
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Pauwelsstrasse 30, 52074, Aachen, Germany.,JARA Translational Brain Medicine, Aachen, Germany
| | - Juliane Mühlhaus
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Pauwelsstrasse 30, 52074, Aachen, Germany.,JARA Translational Brain Medicine, Aachen, Germany.,Department of Computer Science, Speech and Language Therapy, Trier University of Applied Sciences, Trier, Germany
| |
Collapse
|
18
|
Ouyang M, Cai X, Zhang Q. The Effect of Lexical Cohort Size Is Independent of Semantic Context Effects in a Picture-Word Interference Task: A Combined ERP and sLORETA Study. Front Hum Neurosci 2019; 13:439. [PMID: 31920597 PMCID: PMC6933526 DOI: 10.3389/fnhum.2019.00439] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Accepted: 11/29/2019] [Indexed: 11/21/2022] Open
Abstract
Lexical cohort size is known to play an important role in the magnitude of semantic interference during picture naming in continuous and blocking naming tasks. Nevertheless, whether and how lexical cohort size influences semantic context effects in a picture-word interference (PWI) task remains unclear. To address this issue, participants were required to name pictures, which were paired with both semantically related and unrelated distractors, from both large and small lexical cohorts while electroencephalogram (EEG) signals were recorded. Behavior results showed a semantic interference effect but no interaction between semantic relatedness and lexical cohort size in naming latencies. ERPs and correlation analyses revealed that semantic interference effects occurred at the lexical level in the time windows of 200-400 and 400-600 ms, and lexical cohort size effects occurred at the conceptual level in the time window of 100-200 ms and at the lexical level in the time windows of 200-400 ms. Critically, no interaction between two variables was found, reflecting that lexical cohort size is independent of semantic interference for categorical relations in the PWI. sLORETA results found stronger brain activations for large lexical cohorts at the left superior temporal gyrus and inferior frontal gyrus in the time interval of 250-300 ms, which may relate to lexical selection and self-monitoring. Our findings provide evidence for the swinging lexical network rather than the response exclusion hypothesis in spoken production.
Collapse
Affiliation(s)
| | | | - Qingfang Zhang
- Department of Psychology, Renmin University of China, Beijing, China
| |
Collapse
|
19
|
Siempis T, Tsakiris C, Alexiou GA, Xydis VG, Voulgaris S, Argyropoulou MI. Diagnostic performance of diffusion and perfusion MRI in differentiating high from low-grade meningiomas: A systematic review and meta-analysis. Clin Neurol Neurosurg 2019; 190:105643. [PMID: 31865221 DOI: 10.1016/j.clineuro.2019.105643] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 12/13/2019] [Accepted: 12/15/2019] [Indexed: 10/25/2022]
Abstract
OBJECTIVES The purpose of the present meta-analysis and systematic review was to evaluate the currently published data on the potential role of perfusion (PWI) and diffusion (DWI) weighted imaging for the assessment of meningioma grade. PATIENTS AND METHODS A search of MEDLINE and relative reference lists was conducted to identify all the eligible studies assessing the diagnostic performance of DWI and PWI in grading meningiomas. Meta-Disc and Rev-Man were used for the statistical analysis. Methodological quality and risk of bias were assessed with the use of the updated Quality assessment of the diagnostic accuracy (QUADAS-2) tool. Pooled sensitivity, specificity and area under the summary receiver operating characteristic curve were calculated individually for DWI and PWI to demonstrate the diagnostic performance of each modality. RESULTS Fourteen studies with 1063 patients were included. The 8 studies evaluating DWI showed a pooled sensitivity of 80% (95% CI, 74%-86%) and a pooled specificity of 76% (95% CI, 72%-79%). As for the 6 remaining studies concerning PWI, the pooled sensitivity and specificity were found 80% (95% CI, 71%-88%) and 91% (95% CI, 87%-94%), respectively. The area under the SROC curve was 0.94 (95% CI) for PWI and 0.91 (95% CI) for DWI. The comparison of the two AUCs showed that neither technique was superior with regards to the diagnostic performance. CONCLUSIONS The current evidence proves that both techniques are efficient at differentiating high from low-grade meningiomas.
Collapse
Affiliation(s)
- Timoleon Siempis
- Department of Neurosurgery, Medical School, University of Ioannina, Greece
| | | | - George A Alexiou
- Department of Neurosurgery, Medical School, University of Ioannina, Greece.
| | | | - Spyridon Voulgaris
- Department of Neurosurgery, Medical School, University of Ioannina, Greece
| | | |
Collapse
|
20
|
Blackman A, Browne M, Rockloff M, Hing N, Russell AMT. Contrasting Effects of Gambling Consumption and Gambling Problems on Subjective Wellbeing. J Gambl Stud 2019; 35:773-792. [PMID: 31175554 DOI: 10.1007/s10899-019-09862-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Most research on gambling focuses on the negative consequences associated with excessive consumption, which implicitly leads to a reduction in health and wellbeing. However, few studies have measured subjective wellbeing with respect to gambling involvement, and almost none has attempted to distinguish the separate effects of consumption and problems. We used the Personal Wellbeing Index (PWI) in two surveys with different recruitment criteria. Study 1 (N = 1524, 50.6% female) was designed to compare differences in personal wellbeing among gamblers, and Study 2 (N = 1586, 70.2% female) compared wellbeing between gamblers and non-gamblers. Participants provided demographic information, and answered questions allowing them to be grouped into high/low levels of consumption, and problem gambling risk categories. After accounting for gambling problems, higher consumption was associated with higher wellbeing. Study 2 showed consistent results; revealing that both high and low consumption non-problem gamblers (NPGs) had higher personal wellbeing than non-gamblers. Nevertheless, the deleterious effect of gambling problems on wellbeing was larger than the effect of consumption. After accounting for population prevalence (i.e., per capita), only 15.3% of the negative influence of gambling problems on PWI was attributable to problem gamblers; the remainder associated with lower risk categories. Although results were consistent when controlling for demographic covariates, the positive link between consumption and wellbeing may be due to unmeasured variables such as personality traits, health, and socioeconomic status. Nevertheless, the assessment of subjective wellbeing provides a unique perspective on both the positive and negative effects of gambling.
Collapse
Affiliation(s)
- Amanda Blackman
- School of Medical, Health, Medical and Applied Sciences, Central Queensland University, B8 G.47 University Drive, Bundaberg, QLD, 4670, Australia
| | - Matthew Browne
- School of Medical, Health, Medical and Applied Sciences, Central Queensland University, B8 G.47 University Drive, Bundaberg, QLD, 4670, Australia.
| | - Matthew Rockloff
- School of Medical, Health, Medical and Applied Sciences, Central Queensland University, B8 G.47 University Drive, Bundaberg, QLD, 4670, Australia
| | - Nerilee Hing
- School of Medical, Health, Medical and Applied Sciences, Central Queensland University, B8 G.47 University Drive, Bundaberg, QLD, 4670, Australia
| | - Alex M T Russell
- School of Medical, Health, Medical and Applied Sciences, Central Queensland University, B8 G.47 University Drive, Bundaberg, QLD, 4670, Australia
| |
Collapse
|
21
|
Wang Y, Liang H, Luo Y, Zhou Y, Jin L, Wang S, Bi Y. History of Hypertension Is Associated With MR Hypoperfusion in Chinese Inpatients With DWI-Negative TIA. Front Neurol 2019; 10:867. [PMID: 31474927 PMCID: PMC6702658 DOI: 10.3389/fneur.2019.00867] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 07/26/2019] [Indexed: 12/28/2022] Open
Abstract
Objectives: The present study aimed to examine the prevalence of and risk factors for magnetic resonance (MR) perfusion abnormality in a Chinese population with transient ischemic attack (TIA) and normal diffusion-weighted imaging (DWI) findings. Methods: Patients with TIA admitted to our stroke center between January 2015 and October 2017 were recruited to the present study. MRI, including both DWI and perfusion-weighted imaging (PWI), was performed within 7 days of symptom onset. Time to maximum of the residue function (Tmax) maps were evaluated using the RAPID software (Ischemaview USA, Version 4.9) to determine hypoperfusion. Multivariate analysis was used to assess perfusion findings, clinical variables, medical history, cardio-metabolic, and the ABCD2 scores (age, blood pressure, clinical features, symptom duration, and diabetes). Results: Fifty-nine patients met the inclusion criteria. The prevalence of MR perfusion Tmax ≥ 4 s ≥ 0 ml and ≥ 10 mL were 72.9% (43/59) and 42.4% (25/59), respectively. Multivariate analyses revealed that history of hypertension is an independent factor associated with MR perfusion abnormality (Tmax ≥ 4 s ≥ 10 mL) for Chinese patients with TIA (P = 0.033, adjusted OR = 4.11, 95% CI = 1.12–15.11). Proximal artery stenosis (>50%) tended to lead to a larger PW lesion on MRI (p = 0.067, adjusted OR = 3.60, 95% CI = 0.91–14.20). Conclusion: Our results suggest that the prevalence of perfusion abnormality is high as assessed by RAPID using the parametric Tmax ≥ 4 s. History of hypertension is a strong predictor of focal perfusion abnormality as calculated by RAPID on Tmax map of TIA patients with negative DWI findings.
Collapse
Affiliation(s)
- Yue Wang
- Department of Neurology, Shanghai Fourth People's Hospital Affiliated to Tongji University School of Medicine, Shanghai, China.,Department of Neurology, Translational Research Institute of Brain and Brain-Like Intelligence, Shanghai Fourth People's Hospital Affiliated to Tongji University School of Medicine, Shanghai, China
| | - Huazheng Liang
- Department of Neurology, Shanghai Fourth People's Hospital Affiliated to Tongji University School of Medicine, Shanghai, China.,Department of Neurology, Translational Research Institute of Brain and Brain-Like Intelligence, Shanghai Fourth People's Hospital Affiliated to Tongji University School of Medicine, Shanghai, China
| | - Yu Luo
- Department of Neurology, Translational Research Institute of Brain and Brain-Like Intelligence, Shanghai Fourth People's Hospital Affiliated to Tongji University School of Medicine, Shanghai, China.,Department of Radiology, Shanghai Fourth People's Hospital Affiliated to Tongji University School of Medicine, Shanghai, China
| | - Yuan Zhou
- Department of Neurology, Shanghai Fourth People's Hospital Affiliated to Tongji University School of Medicine, Shanghai, China.,Department of Neurology, Translational Research Institute of Brain and Brain-Like Intelligence, Shanghai Fourth People's Hospital Affiliated to Tongji University School of Medicine, Shanghai, China
| | - Lingjing Jin
- Department of Neurology, Tongji Hospital, Tongji University, Shanghai, China
| | - Shaoshi Wang
- Department of Neurology, Shanghai Fourth People's Hospital Affiliated to Tongji University School of Medicine, Shanghai, China.,Department of Neurology, Translational Research Institute of Brain and Brain-Like Intelligence, Shanghai Fourth People's Hospital Affiliated to Tongji University School of Medicine, Shanghai, China
| | - Yong Bi
- Department of Neurology, Shanghai Fourth People's Hospital Affiliated to Tongji University School of Medicine, Shanghai, China.,Department of Neurology, Translational Research Institute of Brain and Brain-Like Intelligence, Shanghai Fourth People's Hospital Affiliated to Tongji University School of Medicine, Shanghai, China
| |
Collapse
|
22
|
Neska-Matuszewska M, Zimny A, Bladowska J, Czarnecka A, Sąsiadek M. The role of diffusion and perfusion magnetic resonance imaging in differentiation of haemangioblastomas and pilocytic astrocytomas. Pol J Radiol 2018; 83:e197-203. [PMID: 30627235 DOI: 10.5114/pjr.2018.75870] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 06/06/2018] [Indexed: 12/12/2022] Open
Abstract
Purpose Haemangioblastomas (HABLs) and pilocytic astrocytomas (PAs) are brain tumours presenting similar appearance and location in conventional magnetic resonance (MR) imaging. The purpose of our study was to determine whether a detailed analysis of diffusion (DWI) and perfusion (PWI) characteristics can be useful in preoperative differentiation of these tumours. Material and methods The study group consisted of biopsy proven six HABLs and six PAs, which underwent preoperative standard MR examinations including PWI and DWI. In PWI relative cerebral blood volume (rCBV) and the shape of perfusion curves (parameters of peak height - rPH and percentage of signal recovery - rPSR) were analysed. All perfusion parameters were measured for the entire tumour core (mean rCBV, mean rPH, mean rPSR) and in regions with maximal values (max rCBV, max rPH, max rPSR). In DWI parameters of apparent diffusion coefficient (ADC) from the entire tumour core (mean ADC) and in regions with minimal values (min ADC) were evaluated. Results Compared to PAs, HABLs presented significantly higher rCBV and rPH values and lower mean rPSR value. PAs showed significantly lower rCBV and rPH values and higher mean rPSR value. Mean rCBV showed no overlap in the values between HABLs and PAs, and thus it provided the highest accuracy in differentiating between them. Max rPSR, mean ADC, and min ADC did not show any significant differences. Conclusions High rCBV values and deep perfusion curves with only partial return to the baseline are characteristic features of HABLs differentiating them from PAs, which show lower rCBV values and perfusion curves overshooting the baseline. Diffusion parameters are not useful in differentiation of these tumours.
Collapse
|
23
|
Förster A, Brehmer S, Seiz-Rosenhagen M, Mildenberger I, Giordano FA, Wenz H, Reuss D, Hänggi D, Groden C. Heterogeneity of glioblastoma with gliomatosis cerebri growth pattern on diffusion and perfusion MRI. J Neurooncol 2018; 142:103-109. [PMID: 30565029 DOI: 10.1007/s11060-018-03068-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Accepted: 11/30/2018] [Indexed: 01/30/2023]
Abstract
BACKGROUND AND PURPOSE Gliomatosis cerebri (GC) is a rare growth pattern of glioblastoma whose diffuse nature is reflected by unspecific, relatively uniform findings on conventional MRI. In the present study we sought to evaluate the additional value of diffusion (DWI) and perfusion weighted (PWI) MRI for a more detailed characterization. METHODS We analyzed the MRI findings in patients with histologically proven glioblastoma with GC growth pattern with a specific emphasis on T2 lesion pattern, volume, relative apparent diffusion coefficient (rACD), and relative cerebral blood volume (rCBV) and compared these to age-/gender-matched patients with localized glioblastoma. RESULTS Overall, 16 patients (median age 59.5 years, 4 male) were included in the study. Of these, 8 patients had a glioblastoma with GC growth pattern, and 8 a classical localized growth pattern. While the median rADC (1.27 [IQR 1.12-1.41]) within the T2 lesion was significant lower in glioblastoma with GC growth pattern compared to localized glioblastoma (1.74 [IQR 1.45-1.96]; p = 0.003), the median T2 lesion volume and rCBV within the T2 lesion did not differ significantly. Furthermore, six patients with glioblastoma with GC growth pattern showed focal areas with significantly reduced rADC (p = 0.043), and/or increased rCBV (p = 0.028). CONCLUSIONS Lower rADC in glioblastoma with GC growth pattern might reflect the diffuse tumor cell infiltration whereas focal areas with decreased rADC and/or increased rCBV probably indicate high tumor cell density and/or abnormal tumor vessels which may be useful for biopsy guidance.
Collapse
Affiliation(s)
- Alex Förster
- Department of Neuroradiology, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany.
| | - Stefanie Brehmer
- Department of Neurosurgery, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Marcel Seiz-Rosenhagen
- Department of Neurosurgery, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Iris Mildenberger
- Department of Neurology, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Frank A Giordano
- Department of Radiation Oncology, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Holger Wenz
- Department of Neuroradiology, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany
| | - David Reuss
- Department of Neuropathology, University Hospital Heidelberg, Heidelberg, Germany
- Clinical Cooperation Unit Neuropathology, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Daniel Hänggi
- Department of Neurosurgery, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Christoph Groden
- Department of Neuroradiology, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany
| |
Collapse
|
24
|
Arrigoni F, Calloni S, Huisman TAGM, Chiapparini L. Conventional MRI. Handb Clin Neurol 2018; 154:219-34. [PMID: 29903441 DOI: 10.1016/B978-0-444-63956-1.00013-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/26/2023]
Abstract
Conventional magnetic resonance imaging (MRI) allows for a detailed noninvasive visualization/examination of posterior fossa structures and represents a fundamental step in the diagnostic workup of many cerebellar disorders. In the first part of this chapter methodologic issues, like the correct choice of hardware (magnets, coils), pro and cons of the different MRI sequences, and patient management during the examination are discussed. In the second part, the MRI anatomy of the cerebellum, as noted on the various conventional MRI sequences, as well as a detailed description of cerebellar maturational processes from birth to childhood and into adulthood, are reported. Volumetric studies on the cerebellar growth based on three-dimensional MRI sequences are also presented. Moreover, we briefly discuss two main topics regarding conventional MRI of the cerebellum that have generated some debate in recent years: the differentiation between cerebellar atrophy, hypoplasia, and pontocerebellar hypoplasia, and signal changes of dentate nuclei after repetitive gadolinium-based contrast injections. The advantages and benefits of advanced neuroimaging techniques, including 1H magnetic resonance spectroscopy, diffusion-weighted imaging, diffusion tensor imaging, and perfusion-weighted imaging are discussed in the last section of the chapter.
Collapse
|
25
|
Pala A, Reske SN, Eberhardt N, Scheuerle A, König R, Schmitz B, Beer AJ, Wirtz CR, Coburger J. Diagnostic accuracy of intraoperative perfusion-weighted MRI and 5-aminolevulinic acid in relation to contrast-enhanced intraoperative MRI and 11C-methionine positron emission tomography in resection of glioblastoma: a prospective study. Neurosurg Rev 2018; 42:471-479. [PMID: 29808321 DOI: 10.1007/s10143-018-0987-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 05/06/2018] [Accepted: 05/21/2018] [Indexed: 10/14/2022]
Abstract
The aim of our study was to compare depicted pre-, intra-, and postoperative tumor volume of met-PET, perfusion-weighed MRI (PWI), and Gd-DTPA MRI. Further, to assess their sensitivity and specificity in correlation with histopathological specimen. Inclusion criteria of the prospective study were histological confirmed glioblastoma (GB), age > 18, and eligible for gross total resection (GTR). Met-PET was performed before and after surgery. Gd-DTPA MRI and PWI were performed before, during, and after surgery. A combined 5-aminolevulinic acid (5-ALA) and iMRI-guided surgery was performed. Volumetric analysis was evaluated for all imaging modalities except for 5-ALA. A total of 59 navigated biopsies were taken. Sensitivity and specificity were calculated for Gd-DTPA MRI, PWI, met-PET, and 5-ALA according to the histology of specimen. Met-PET depicted significantly larger tumor volume before surgery (p = 0.01) compared to PWI and Gd-DTPI MRI. We found no significant difference in tumor volume between met-PET and PWI after surgery (p = 0.059). Both PWI and met-PET showed significantly larger tumor volume after surgery when compared to Gd-DTPA (p = 0.018 and p = 0.003, respectively). Intraoperative PWI reading was impaired in 33.3% due to artifacts. Met-PET showed the highest sensitivity for detection of GB with 95%. The lowest sensitivity was found with Gd-DTPA MRI (50%), while 5-ALA and intraoperative PWI showed similar results (69 and 67%). Met-Pet is the imaging modality with the highest sensitivity to detect a residual tumor in GB. Intraoperative PWI seems to have a synergistic effect to Gd-DTPA and 5-ALA. However, its value may be limited by artifacts. Both pre- and intraoperative PWI cannot substitute met-PET in tumor detection.
Collapse
Affiliation(s)
- Andrej Pala
- Department of Neurosurgery, University of Ulm, Ludwig-Heilmeyerstr. 2, 89312, Günzburg, Germany.
| | - Sven N Reske
- Department of Nuclear Medicine, University of Ulm, Albert-Einstein-Allee 23, 89081, Ulm, Germany
| | - Nina Eberhardt
- Department of Nuclear Medicine, University of Ulm, Albert-Einstein-Allee 23, 89081, Ulm, Germany
| | - Angelika Scheuerle
- Department of Neuropathology, University of Ulm, Ludwig-Heilmeyerstr. 2, 89312, Günzburg, Germany
| | - Ralph König
- Department of Neurosurgery, University of Ulm, Ludwig-Heilmeyerstr. 2, 89312, Günzburg, Germany
| | - Bernd Schmitz
- Department of Neuroradiology, University of Ulm, Ludwig-Heilmeyerstr. 2, 89312, Günzburg, Germany
| | - Ambros J Beer
- Department of Nuclear Medicine, University of Ulm, Albert-Einstein-Allee 23, 89081, Ulm, Germany
| | - Christian R Wirtz
- Department of Neurosurgery, University of Ulm, Ludwig-Heilmeyerstr. 2, 89312, Günzburg, Germany
| | - Jan Coburger
- Department of Neurosurgery, University of Ulm, Ludwig-Heilmeyerstr. 2, 89312, Günzburg, Germany
| |
Collapse
|
26
|
Abstract
Stroke consists of the loss of cerebral functions resulting from the interruption of blood supply to a region of the brain, and represents the second cause of death and the leading cause of major disability in adults in Europe. Stroke is a very active field of research at preclinical and clinical levels, and Magnetic Resonance Imaging (MRI) is one of the most powerful tools that scientist and clinicians have for the study of the onset, evolution and consequences of this devastating disease, as well as for the monitoring of the success of available treatments, or for the development of novel therapeutic strategies.MRI can tackle the study of stroke from different points of view, and at scales ranging from subcellular to systems biology level. Magnetic resonance spectroscopy (MRS) allows the noninvasive measurement of the levels of principal metabolites in the brain, and how they change during the course of the disease, or in response to therapy. Glutamate, in particular, is very important in the field of stroke. Several anatomical MR techniques allow the characterization of the lesion volumes, the formation of cytotoxic and vasogenic edema, changes in cerebral blood flow and volume, structural changes in gray and white matter, the obtaining of the vascular architecture and status, etc. At functional level, diverse modalities of functional MRI (fMRI) allow the assessment of the alteration in the function and organization of neuronal networks of the subject under study, as a consequence of the disease or in response to treatment. Finally, emerging imaging modalities that include temperature and pH mapping of the brain, imaging by chemical exchange saturation transfer effect (CEST), all of them closely related to tissue status, or the use of contrast agents for the targeting of tissue in theranostic approaches or for cell tracking studies in cell-based therapies, etc., are only a few examples of the power and versatility of MRI as a definitive tool for the study of stroke.In this work we will set our focus on preclinical imaging of stroke models, emphasizing the most commonly used imaging modalities in a stroke-dedicated research laboratory. However, advanced techniques will be briefly discussed, providing references to specialized literature for more advanced readers. Thus, the aim of this chapter consist in the description of a simple imaging protocol for the study of the most important and common aspects of stroke in a research laboratory.
Collapse
Affiliation(s)
- Pedro Ramos-Cabrer
- Molecular Imaging Unit, CIC biomaGUNE, Paseo de Miramón 182, 20009, Donostia-San Sebastián, Spain.
- Ikerbasque, Basque Foundation for Science, María Díaz de Haro 3, 48013, Bilbao, Spain.
| | - Daniel Padro
- Molecular Imaging Unit, CIC biomaGUNE, Paseo de Miramón 182, 20009, Donostia-San Sebastián, Spain
| |
Collapse
|
27
|
Abstract
INTRODUCTION Initial diagnostics and follow-up of gliomas is usually based on contrast-enhanced MRI. However, the capacity of standard MRI to differentiate neoplastic tissue from posttherapeutic effects such as pseudoprogression is limited. Advanced neuroimaging methods may provide relevant additional information, which allow for a more accurate diagnosis especially in clinically equivocal situations. This review article focuses predominantly on PET using radiolabeled amino acids and advanced MRI techniques such as perfusion-weighted imaging (PWI) and summarizes the efforts of these methods regarding the identification of pseudoprogression after glioma therapy. Areas covered: The current literature on pseudoprogression in the field of brain tumors, with a focus on gliomas is summarized. A literature search was performed using the terms 'pseudoprogression', 'temozolomide', 'glioblastoma', 'PET', 'PWI', 'radiochemotherapy', and derivations thereof. Expert commentary: The present literature provides strong evidence that PWI MRI and amino acid PET can be of great value by providing valuable additional diagnostic information in order to overcome the diagnostic challenge of pseudoprogression. Despite various obstacles such as the still limited availability of amino acid PET and the lack of standardization of PWI, the diagnostic improvement probably results in relevant benefits for brain tumor patients and justifies a more widespread use of these diagnostic tools.
Collapse
Affiliation(s)
- Norbert Galldiks
- a Department of Neurology , University of Cologne , Cologne , Germany.,b Institute of Neuroscience and Medicine , Forschungszentrum Jülich , Jülich , Germany.,c Center of Integrated Oncology (CIO) , Universities of Cologne and Bonn , Cologne , Germany
| | - Martin Kocher
- d Department of Radiation Oncology , University of Cologne , Cologne , Germany
| | - Karl-Josef Langen
- b Institute of Neuroscience and Medicine , Forschungszentrum Jülich , Jülich , Germany.,e Department of Nuclear Medicine , University of Aachen , Aachen , Germany
| |
Collapse
|
28
|
Livne M, Madai VI, Brunecker P, Zaro-Weber O, Moeller-Hartmann W, Heiss WD, Mouridsen K, Sobesky J. A PET-Guided Framework Supports a Multiple Arterial Input Functions Approach in DSC-MRI in Acute Stroke. J Neuroimaging 2017; 27:486-492. [PMID: 28207200 DOI: 10.1111/jon.12428] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Accepted: 01/02/2017] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE In acute stroke, arterial-input-function (AIF) determination is essential for obtaining perfusion estimates with dynamic susceptibility-weighted contrast-enhanced magnetic resonance imaging (DSC-MRI). Standard DSC-MRI postprocessing applies single AIF selection, ie, global AIF. Physiological considerations, however, suggest that a multiple AIFs selection method would improve perfusion estimates to detect penumbral flow. In this study, we developed a framework based on comparable DSC-MRI and positron emission tomography (PET) images to compare the two AIF selection approaches and assess their performance in penumbral flow detection in acute stroke. METHODS In a retrospective analysis of 17 sub(acute) stroke patients with consecutive MRI and PET scans, voxel-wise optimized AIFs were calculated based on the kinetic model as derived from both imaging modalities. Perfusion maps were calculated based on the optimized-AIF using two methodologies: (1) Global AIF and (2) multiple AIFs as identified by cluster analysis. Performance of penumbral-flow detection was tested by receiver-operating characteristics (ROC) curve analysis, ie, the area under the curve (AUC). RESULTS Large variation of optimized AIFs across brain voxels demonstrated that there is no optimal single AIF. Subsequently, the multiple-AIF method (AUC range over all maps: .82-.90) outperformed the global AIF methodology (AUC .72-.85) significantly. CONCLUSIONS We provide PET imaging-based evidence that a multiple AIF methodology is beneficial for penumbral flow detection in comparison with the standard global AIF methodology in acute stroke.
Collapse
Affiliation(s)
- Michelle Livne
- Center for Stroke Research Berlin (CSB), Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Vince I Madai
- Center for Stroke Research Berlin (CSB), Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Peter Brunecker
- Center for Stroke Research Berlin (CSB), Charité - Universitätsmedizin Berlin, Berlin, Germany
| | | | | | | | - Kim Mouridsen
- Center of Functionally Integrative Neuroscience, Aarhus University, Denmark
| | - Jan Sobesky
- Center for Stroke Research Berlin (CSB), Charité - Universitätsmedizin Berlin, Berlin, Germany
| |
Collapse
|
29
|
Abstract
Traumatic brain injury (TBI) is a leading cause of death and disability in the USA. Common causes of TBI include falls, violence, injuries from wars, and vehicular and sporting accidents. The initial direct mechanical damage in TBI is followed by progressive secondary injuries such as brain swelling, perturbed cerebral blood flow (CBF), abnormal cerebrovascular reactivity (CR), metabolic dysfunction, blood-brain-barrier disruption, inflammation, oxidative stress, and excitotoxicity, among others. Magnetic resonance imaging (MRI) offers the means to noninvasively probe many of these secondary injuries. MRI has been used to image anatomical, physiological, and functional changes associated with TBI in a longitudinal manner. This chapter describes controlled cortical impact (CCI) TBI surgical procedures, a few common MRI protocols used in TBI imaging, and, finally, image analysis pertaining to experimental TBI imaging in rats.
Collapse
Affiliation(s)
- Qiang Shen
- Research Imaging Institute, University of Texas Health Science Center, 8403 Floyd Curl Dr, San Antonio, TX, 78229, USA. .,Department of Ophthalmology, University of Texas Health Science Center, San Antonio, TX, USA. .,Department of Radiology, University of Texas Health Science Center, San Antonio, TX, USA.
| | - Lora Tally Watts
- Research Imaging Institute, University of Texas Health Science Center, 8403 Floyd Curl Dr, San Antonio, TX, 78229, USA.,Departments of Cellular and Structure Biology, University of Texas Health Science Center, San Antonio, TX, USA
| | - Wei Li
- Research Imaging Institute, University of Texas Health Science Center, 8403 Floyd Curl Dr, San Antonio, TX, 78229, USA.,Department of Ophthalmology, University of Texas Health Science Center, San Antonio, TX, USA
| | - Timothy Q Duong
- Research Imaging Institute, University of Texas Health Science Center, 8403 Floyd Curl Dr, San Antonio, TX, 78229, USA. .,Department of Ophthalmology, University of Texas Health Science Center, San Antonio, TX, USA. .,Department of Radiology, University of Texas Health Science Center, San Antonio, TX, USA. .,Department of Veterans Affairs, South Texas Veterans Health Care System, San Antonio, TX, USA.
| |
Collapse
|
30
|
Brown TA, Luby M, Shah J, Giannakidis D, Latour LL. Magnetic Resonance Imaging in Acute Ischemic Stroke Patients with Mild Symptoms: An Opportunity to Standardize Intravenous Thrombolysis. J Stroke Cerebrovasc Dis 2015; 24:1832-40. [PMID: 25997980 DOI: 10.1016/j.jstrokecerebrovasdis.2015.04.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2015] [Accepted: 04/12/2015] [Indexed: 10/23/2022] Open
Abstract
BACKGROUND Patients presenting with mild stroke symptoms are excluded inconsistently from intravenous (IV) thrombolysis. We aimed to compare acute magnetic resonance imaging findings in patients with mild symptoms to those with more severe deficits to identify clinically mild patients who might benefit from IV thrombolysis. METHODS We retrospectively studied consecutive stroke patients presenting with perfusion deficit who underwent time-of-flight magnetic resonance angiography within 24 hours of time last seen normal. Two raters measured the lesion volumes on diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) with mismatch (MM) calculated as PWI minus DWI. Occlusion site was categorized as "proximal," "distal," or "magnetic resonance angiography-negative" by consensus review. Stroke with mild symptoms was defined as admit National Institutes of Health Stroke Scale score of 4 or less. Values were reported as n (%). RESULTS Ninety-one patients were included; 56 (61.5%) with nonmild and 35 (38.5%) with mild symptoms. After stratifying for occlusion site, there were no differences in PWI and MM lesion volumes for the nonmild versus mild patients (P = .34-.98 and P = .54-1, respectively). Furthermore, there was a trend for thrombolyzed mild stroke patients (88%, n = 7 of 8) to more likely have a favorable clinical outcome (discharge modified Rankin score ≤ 2) versus untreated patients (70%, n = 16 of 23). CONCLUSIONS When present, conspicuous vessel occlusions in clinically mild stroke patients are concomitant with similar perfusion deficit and MM volumes in more clinically severe stroke patients. Coupled with a trend toward better outcomes in mild stroke patients who were treated with IV tissue plasminogen activator (t-PA), this could indicate that advanced imaging may be used in standardizing the way these patients are selected for IV t-PA therapy.
Collapse
Affiliation(s)
- Tyler A Brown
- Stroke Diagnostics and Therapeutics Branch, National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, Maryland
| | - Marie Luby
- Stroke Diagnostics and Therapeutics Branch, National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, Maryland
| | - Jignesh Shah
- Stroke Diagnostics and Therapeutics Branch, National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, Maryland
| | - Dimitrios Giannakidis
- Stroke Diagnostics and Therapeutics Branch, National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, Maryland
| | - Lawrence L Latour
- Stroke Diagnostics and Therapeutics Branch, National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, Maryland.
| |
Collapse
|
31
|
Kim YW, Kim HJ, Choi SH, Kim DC. Prominent hypointense veins on susceptibility weighted image in the cat brain with acute infarction: DWI, SWI, and PWI. Acta Radiol 2014; 55:1008-14. [PMID: 24136983 DOI: 10.1177/0284185113508181] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND The multiple prominent hypointense veins on susceptibility-weighted imaging (SWI) have been found in the ischemic territory of patients with acute ischemic stroke. Venous side is the unknown area in the hemodynamics of brain infarction. PURPOSE To evaluate the venous aspect in acute brain infarction through an animal study. MATERIAL AND METHODS The acute infarction in cat brains was induced with a bolus infusion of 0.25 mL of triolein through one side of the common carotid artery. The magnetic resonance (MR) images, including diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC) map, SW, and perfusion-weighted (PWI) images, were obtained serially at 2 h (n = 17), 1 day (n = 11), and 4 days (n = 4) after triolein infusion. The obtained MR images were evaluated qualitatively and quantitatively. For qualitative assessment, the signal intensity of the serial MR images was evaluated. The presence or absence and the location with serial changes of infarction were identified on DWI and ADC map images. The presence or absence of prominent hypointense veins and the serial changes of cortical veins were also evaluated on SWI. Quantitative assessment was performed by comparing the relative cerebral blood volume (rCBV), cerebral blood flow (rCBF), and mean transit times (MTT) of the lesions with those of the contralateral normal side calculated on PWI. The serial changes of rCBV, rCBF, and MTT ratio were also evaluated. RESULTS Acute infarction in the first and second medial gyrus of lesion hemisphere was found by qualitative evaluation of DWI and ADC map images. On the serial evaluation of SWI, the cortical veins of cat brain with infarction were obscured at 2 h and then re-appeared at 1 day. The hemorrhage transformation and prominent hypointense veins were seen at 4 days on SWI. The quantitative evaluation revealed increased MTT ratios and decreased rCBV and rCBF ratios on PWIs in the acute infarction of cat brain. CONCLUSION The prominent hypointense veins on SWI were seen in the half of the acute infarction at 4 days. The prominent hypointense veins on SWI may have good agreement with the increased MTT ratio.
Collapse
Affiliation(s)
- Yong-Woo Kim
- Department of Radiology, Pusan National University School of Medicine, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Republic of Korea
| | - Hak Jin Kim
- Department of Radiology, Pusan National University School of Medicine, Biomedical Research Institute, Pusan National University Hospital, Pusan, Republic of Korea
| | - Seon Hee Choi
- Pusan National University Postgraduate School, Pusan, Republic of Korea
| | - Dong Chan Kim
- Seoul National University School of Veterinary Medicine, Seoul, Republic of Korea
| |
Collapse
|
32
|
Leigh R, Urrutia VC, Llinas RH, Gottesman RF, Krakauer JW, Hillis AE. A comparison of two methods for MRI classification of at-risk tissue and core infarction. Front Neurol 2014; 5:155. [PMID: 25232348 PMCID: PMC4153314 DOI: 10.3389/fneur.2014.00155] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 07/31/2014] [Indexed: 01/19/2023] Open
Abstract
Objective: To compare how at-risk tissue and core infarction were defined in two major trials that tested the use of MRI in selecting acute stroke patients for endovascular recanalization therapy. Methods: MRIs from 12 patients evaluated for possible endovascular therapy were processed using the methods published from two major trials, MR RESCUE and DEFUSE 2. Specifically, volumes of at-risk tissue and core infarction were generated from each patient’s MRI. MRIs were then classified as whether or not they met criteria for salvageable tissue: “penumbral pattern” for MR RESCUE and/or “target profile” for DEFUSE 2 as defined by each trial. Results: Volumes of at-risk tissue measured by the two definitions were correlated (p = 0.017) while the volumes of core infarct were not (p = 0.059). The volume of at-risk tissue was consistently larger when defined by the penumbral pattern than the target profile while the volume of core infarct was consistently larger when defined by the target profile than the penumbral pattern. When these volumes were used to classify the MRI scans, 9 out of 12 patients (75%) were classified as having a penumbral pattern, while only 4 out of 12 patients (33%) were classified as having a target profile. Of the 9 patients classified as penumbral pattern, 5 (55%) were classified differently by the target profile. Interpretation: Our analysis found that the MR RESCUE trial defined salvageable tissue in a way that made it more likely for patients be labeled as favorable for treatment. For the cohort of patients examined in this study, had they been enrolled in both trials, most of the patients identified as having salvageable tissue by the MR RESCUE trial would not have been considered to have salvageable tissue in the DEFUSE 2 trial. Caution should be taken in concluding that MRI selection for endovascular therapy is not effective as imaging selection criteria were substantially different between the two trials.
Collapse
Affiliation(s)
- Richard Leigh
- Johns Hopkins University School of Medicine , Baltimore, MD , USA
| | - Victor C Urrutia
- Johns Hopkins University School of Medicine , Baltimore, MD , USA
| | - Rafael H Llinas
- Johns Hopkins University School of Medicine , Baltimore, MD , USA
| | | | - John W Krakauer
- Johns Hopkins University School of Medicine , Baltimore, MD , USA
| | - Argye E Hillis
- Johns Hopkins University School of Medicine , Baltimore, MD , USA
| |
Collapse
|
33
|
Muccio CF, Caranci F, D'Arco F, Cerase A, De Lipsis L, Esposito G, Tedeschi E, Andreula C. Magnetic resonance features of pyogenic brain abscesses and differential diagnosis using morphological and functional imaging studies: a pictorial essay. J Neuroradiol 2014; 41:153-67. [PMID: 24957685 DOI: 10.1016/j.neurad.2014.05.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 05/06/2014] [Accepted: 05/10/2014] [Indexed: 10/25/2022]
Abstract
The aim of this paper is to illustrate the potential of magnetic resonance imaging (MRI) in diagnosis, differential diagnosis, treatment planning and evaluation of therapy effectiveness of pyogenic brain abscesses, through the use of morphological (or conventional) and functional (or advanced) sequences. Conventional MRI study is useful for the identification of lesions, to determine the location and morphology and allows a correct hypothesis of nature in the most typical cases. However, the differential diagnosis from other brain lesions, such as non-pyogenic abscesses or necrotic tumors (high-grade gliomas and metastases) is often only possible through the use of functional sequences, as the measurement of diffusion with apparent diffusion coefficient (DWI-ADC), proton magnetic resonance spectroscopy ((1)H-MRS) and perfusion weighted imaging (PWI), which complement the morphological sequences and provide essential information on structural, metabolic and hemodynamic characteristics allowing greater neuroradiological confidence. Modern diagnostic MRI of pyogenic brain abscesses cannot be separated from knowledge, integration and proper use of the morphological and functional sequences.
Collapse
Affiliation(s)
- Carmine Franco Muccio
- Unit of Neuroradiology, Department of Neuroscience, Hospital "Gaetano Rummo", Benevento, Italy
| | - Ferdinando Caranci
- Unit of Neuroradiology, Department of Advanced Biomedical Sciences, University "Federico II", Naples, Italy
| | - Felice D'Arco
- Unit of Neuroradiology, Department of Advanced Biomedical Sciences, University "Federico II", Naples, Italy.
| | - Alfonso Cerase
- Unit of Neuroradiology, Department of Neuroscience, University "Santa Maria alle Scotte", Siena, Italy
| | - Luca De Lipsis
- Department of Critical Care Medicine, Hospital "Fatebenefratelli", Benevento, Italy
| | - Gennaro Esposito
- Unit of Neuroradiology, Department of Neuroscience, Hospital "Gaetano Rummo", Benevento, Italy
| | - Enrico Tedeschi
- Unit of Neuroradiology, Department of Advanced Biomedical Sciences, University "Federico II", Naples, Italy
| | - Cosma Andreula
- Unit of Radiology and Neuroradiology, Anthea Hospital, Bari, Italy
| |
Collapse
|
34
|
Ma H, Wright P, Allport L, Phan TG, Churilov L, Ly J, Zavala JA, Arakawa S, Campbell B, Davis SM, Donnan GA. Salvage of the PWI/DWI mismatch up to 48 h from stroke onset leads to favorable clinical outcome. Int J Stroke 2014; 10:565-70. [PMID: 24612428 DOI: 10.1111/ijs.12203] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 08/20/2013] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND PURPOSE In acute ischemic stroke perfusion/diffusion-weighted image, mismatch using magnetic resonance imaging approximates the ischemic penumbra. For early time windows, mismatch salvage improves clinical outcomes, but uncertainty exists at later time epochs. We hypothesized that (a) mismatch may exist up to 48 h; (b) the proportion of mismatch salvage is time independent; and (c) when salvaged, it improves clinical outcomes. METHODS Magnetic resonance imaging was performed within 48 h of ischemic stroke. Perfusion-weighted image was defined by relative Tmax two-second delay. Perfusion/diffusion-weighted image mismatch was the perfusion-weighted image not overlapped by the diffusion-weighted image when coregistered. Infarct volume and disability (modified Rankin Score) were assessed at three-months. Mismatch salvage was the region not overlapped by final infarction. Favorable outcome was defined as modified Rankin Score 0-1. RESULTS Sixty-six patients were studied [mean age 69.9 years (standard deviation 13.1), initial median National Institute of Health Stroke Scale 9.0 (interquartile range 6.0, 18.3)]. There was no relationship between time of stroke onset and the proportion of mismatch salvaged (P = 0.73). Age (adjusted odds ratio = 0.92, 95% confidence interval 0.86-0.98, P = 0.01), initial National Institute of Health Stroke Scale (adjusted odds ratio = 0.80, 95% confidence interval 0.70-0.92, P < 0.01), mismatch volume (adjusted odds ratio = 0.98, 95% confidence interval 0.968-0.1, P = 0.05), and percentage of mismatch salvage (adjusted odds ratio = 1.04, 95% confidence interval 0.99-1.07, P = 0.05) were independently associated with favorable outcome. CONCLUSION Using coregistered perfusion/diffusion-weighted image criteria, mismatch persists up to 48 h post stroke. For the whole group, the proportion of mismatch salvage remains independent of time and, although the effect is small, its salvage is independently associated with improved clinical outcomes at three-months. Larger sample sizes are needed to determine the time limit for mismatch salvage.
Collapse
Affiliation(s)
- H Ma
- National Stroke Research Institute, Florey Neuroscience Institutes, University of Melbourne, Melbourne, Vic, Australia.,Department of Medicine, Monash Medical Centre, Monash University, Melbourne, Vic, Australia
| | - P Wright
- National Stroke Research Institute, Florey Neuroscience Institutes, University of Melbourne, Melbourne, Vic, Australia
| | - L Allport
- Department of Medicine, Melbourne Brain Centre, Royal Melbourne Hospital, Melbourne, Vic, Australia
| | - T G Phan
- Department of Medicine, Monash Medical Centre, Monash University, Melbourne, Vic, Australia
| | - L Churilov
- National Stroke Research Institute, Florey Neuroscience Institutes, University of Melbourne, Melbourne, Vic, Australia
| | - J Ly
- Department of Medicine, Monash Medical Centre, Monash University, Melbourne, Vic, Australia
| | - J A Zavala
- National Stroke Research Institute, Florey Neuroscience Institutes, University of Melbourne, Melbourne, Vic, Australia
| | - S Arakawa
- National Stroke Research Institute, Florey Neuroscience Institutes, University of Melbourne, Melbourne, Vic, Australia
| | - B Campbell
- Department of Medicine, Melbourne Brain Centre, Royal Melbourne Hospital, Melbourne, Vic, Australia
| | - S M Davis
- Department of Medicine, Melbourne Brain Centre, Royal Melbourne Hospital, Melbourne, Vic, Australia
| | - G A Donnan
- National Stroke Research Institute, Florey Neuroscience Institutes, University of Melbourne, Melbourne, Vic, Australia
| |
Collapse
|
35
|
Filss CP, Galldiks N, Stoffels G, Sabel M, Wittsack HJ, Turowski B, Antoch G, Zhang K, Fink GR, Coenen HH, Shah NJ, Herzog H, Langen KJ. Comparison of 18F-FET PET and perfusion-weighted MR imaging: a PET/MR imaging hybrid study in patients with brain tumors. J Nucl Med 2014; 55:540-5. [PMID: 24578243 DOI: 10.2967/jnumed.113.129007] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
UNLABELLED PET using O-(2-(18)F-fluoroethyl)-L-tyrosine ((18)F-FET) provides important diagnostic information in addition to that from conventional MR imaging on tumor extent and activity of cerebral gliomas. Recent studies suggest that perfusion-weighted MR imaging (PWI), especially maps of regional cerebral blood volume (rCBV), may provide similar diagnostic information. In this study, we directly compared (18)F-FET PET and PWI in patients with brain tumors. METHODS Fifty-six patients with gliomas were investigated using static (18)F-FET PET and PWI. For comparison, 8 patients with meningiomas were included. We generated a set of tumor and reference volumes of interest (VOIs) based on morphologic MR imaging and transferred these VOIs to the corresponding (18)F-FET PET scans and PWI maps. From these VOIs, tumor-to-brain ratios (TBR) were calculated, and normalized histograms were generated for (18)F-FET PET and rCBV maps. Furthermore, in rCBV maps and in (18)F-FET PET scans, tumor volumes, their spatial congruence, and the distance between the local hot spots were assessed. RESULTS For patients with glioma, TBR was significantly higher in (18)F-FET PET than in rCBV maps (TBR, 2.28 ± 0.99 vs. 1.62 ± 1.13; P < 0.001). Histogram analysis of the VOIs revealed that (18)F-FET scans could clearly separate tumor from background. In contrast, deriving this information from rCBV maps was difficult. Tumor volumes were significantly larger in (18)F-FET PET than in rCBV maps (tumor volume, 24.3 ± 26.5 cm(3) vs. 8.9 ± 13.9 cm(3); P < 0.001). Accordingly, spatial overlap of both imaging parameters was poor (congruence, 11.0%), and mean distance between the local hot spots was 25.4 ± 16.1 mm. In meningioma patients, TBR was higher in rCBV maps than in (18)F-FET PET (TBR, 5.33 ± 2.63 vs. 2.37 ± 0.32; P < 0.001) whereas tumor volumes were comparable. CONCLUSION In patients with cerebral glioma, tumor imaging with (18)F-FET PET and rCBV yields different information. (18)F-FET PET shows considerably higher TBRs and larger tumor volumes than rCBV maps. The spatial congruence of both parameters is poor. The locations of the local hot spots differ considerably. Taken together, our data show that metabolically active tumor tissue of gliomas as depicted by amino acid PET is not reflected by rCBV as measured with PWI.
Collapse
Affiliation(s)
- Christian P Filss
- Institute of Neuroscience and Medicine (INM-3, -4, -5), Research Center Jülich, Jülich, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Abstract
OBJECTIVES Migraine with aura is a common neurological disorder, and differentiation from transient ischemic attack or stroke based on clinical symptoms may be difficult. METHODS From an MRI report database we identified 33 patients with migraine with aura and compared these to 33 age-matched ischemic stroke patients regarding perfusion patterns on perfusion-weighted imaging (PWI)-derived maps: time to peak (TTP), mean transit time (MTT), and cerebral blood flow and volume (CBF, CBV). RESULTS In 18/33 (54.5%) patients with migraine with aura, TTP showed areas of hypoperfusion, most of these not limited to the territory of a specific artery but affecting two or more vascular territories. In patients with migraine with aura, TTP (1.09 ± 0.05 vs. 1.47 ± 0.40, p < 0.001) and MTT ratios (1.01 ± 0.10 vs. 1.19 ± 0.21, p = 0.003) were significantly lower compared to patients with ischemic stroke. In contrast to this, CBF and CBV ratios did not differ significantly between both groups. CONCLUSIONS Migraine aura is usually associated with a perfusion deficit not limited to a specific vascular territory, and only a moderate increase of TTP. Thus, hypoperfusion restricted to a single vascular territory in combination with a marked increase of TTP or MTT may be regarded as atypical for migraine aura and suggestive of acute ischemic stroke.
Collapse
Affiliation(s)
- Alex Förster
- Department of Neuroradiology, Universitätsmedizin Mannheim, University of Heidelberg, Germany
| | - Holger Wenz
- Department of Neuroradiology, Universitätsmedizin Mannheim, University of Heidelberg, Germany
| | - Hans U Kerl
- Department of Neuroradiology, Universitätsmedizin Mannheim, University of Heidelberg, Germany
| | - Marc A Brockmann
- Department of Neuroradiology, Universitätsmedizin Mannheim, University of Heidelberg, Germany Department of Diagnostic and Interventional Neuroradiology, University Hospital of the RWTH Aachen, Germany
| | - Christoph Groden
- Department of Neuroradiology, Universitätsmedizin Mannheim, University of Heidelberg, Germany
| |
Collapse
|
37
|
Bladowska J, Zimny A, Knysz B, Małyszczak K, Kołtowska A, Szewczyk P, Gąsiorowski J, Furdal M, Sąsiadek MJ. Evaluation of early cerebral metabolic, perfusion and microstructural changes in HCV-positive patients: a pilot study. J Hepatol 2013; 59:651-7. [PMID: 23680314 DOI: 10.1016/j.jhep.2013.05.008] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Revised: 04/09/2013] [Accepted: 05/06/2013] [Indexed: 12/30/2022]
Abstract
BACKGROUND & AIMS The aim of the study was to evaluate early metabolic perfusion, and microstructural cerebral changes in patients with the hepatitis C virus (HCV) infection and normal appearing brain on plain MR using advanced MR techniques, as well as to assess correlations of MR measurements with the liver histology activity index (HAI). METHODS Fifteen HCV-positive patients and 18 control subjects underwent single voxel MR spectroscopy (MRS), perfusion weighted imaging (PWI), and diffusion tensor imaging (DTI), using a 1.5T MR unit. MRS metabolite ratios (NAA/Cr, Cho/Cr, mI/Cr) were calculated. PWI values of relative cerebral blood volume (rCBV) were assessed from 8 areas including several cortical locations, basal ganglia, and fronto-parietal white matter. DTI fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were obtained from 14 white matter tracts. RESULTS Compared to controls, HCV-positive patients showed significantly (p < 0.05) lower NAA/Cr ratios within frontal and parietal white matters, lower rCBV values within frontal and temporo-parietal cortices, decreased FA values, as well as increased ADC values in several white matter tracts. We also found elevated rCBV values in basal ganglia regions. The increase in mI/Cr and Cho/Cr ratio was correlated with a higher HAI score. CONCLUSIONS The results of advanced MR techniques indicate neurotoxicity of HCV reflected by neuronal impairment within white matter, cortical hypoperfusion, and disintegrity within several white matter tracts. Hyperperfusion in basal ganglia may be an indicator of brain inflammation in HCV patients. Our findings may suggest a biologic link between HCV-related liver disease and cerebral dysfunction.
Collapse
Affiliation(s)
- Joanna Bladowska
- Department of General Radiology, Interventional Radiology and Neuroradiology, Chair of Radiology, Wroclaw Medical University, Borowska 213, 50-556 Wroclaw, Poland.
| | | | | | | | | | | | | | | | | |
Collapse
|