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Dahlberg D, Holm S, Sagen EML, Michelsen AE, Stensland M, de Souza GA, Müller EG, Connelly JP, Revheim ME, Halvorsen B, Hassel B. Bacterial Brain Abscesses Expand Despite Effective Antibiotic Treatment: A Process Powered by Osmosis Due to Neutrophil Cell Death. Neurosurgery 2023; 94:00006123-990000000-00996. [PMID: 38084989 PMCID: PMC10990409 DOI: 10.1227/neu.0000000000002792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 10/22/2023] [Indexed: 04/05/2024] Open
Abstract
BACKGROUND AND OBJECTIVES A bacterial brain abscess is an emergency and should be drained of pus within 24 hours of diagnosis, as recently recommended. In this cross-sectional study, we investigated whether delaying pus drainage entails brain abscess expansion and what the underlying mechanism might be. METHODS Repeated brain MRI of 47 patients who did not undergo immediate pus drainage, pus osmolarity measurements, immunocytochemistry, proteomics, and 18F-fluorodeoxyglucose positron emission tomography. RESULTS Time from first to last MRI before neurosurgery was 1 to 14 days. Abscesses expanded in all but 2 patients: The median average increase was 23% per day (range 0%-176%). Abscesses expanded during antibiotic therapy and even if the pus did not contain viable bacteria. In a separate patient cohort, we found that brain abscess pus tended to be hyperosmolar (median value 360 mOsm; range 266-497; n = 14; normal cerebrospinal fluid osmolarity is ∼290 mOsm). Hyperosmolarity would draw water into the abscess cavity, causing abscess expansion in a ballooning manner through increased pressure in the abscess cavity. A mechanism likely underlying pus hyperosmolarity was the recruitment of neutrophils to the abscess cavity with ensuing neutrophil cell death and decomposition of neutrophil proteins and other macromolecules to osmolytes: Pus analysis showed the presence of neutrophil proteins (protein-arginine deiminases, citrullinated histone, myeloperoxidase, elastase, cathelicidin). Previous studies have shown very high levels of osmolytes (ammonia, amino acids) in brain abscess pus. 18F-fluorodeoxyglucose positron emission tomography showed focal neocortical hypometabolism 1 to 8 years after brain abscess, indicating long-lasting damage to brain tissue. CONCLUSION Brain abscesses expand despite effective antibiotic treatment. Furthermore, brain abscesses cause lasting damage to surrounding brain tissue. These findings support drainage of brain abscesses within 24 hours of diagnosis.
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Affiliation(s)
- Daniel Dahlberg
- Department of Neurosurgery, Oslo University Hospital, Oslo, Norway
| | - Sverre Holm
- Research Institute of Internal Medicine, Oslo University Hospital, Oslo, Norway
| | - Ellen Margaret Lund Sagen
- Research Institute of Internal Medicine, Oslo University Hospital, Oslo, Norway
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Annika Elisabet Michelsen
- Research Institute of Internal Medicine, Oslo University Hospital, Oslo, Norway
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Maria Stensland
- Institute of Immunology and Centre for Immune Regulation, Oslo University Hospital, Oslo, Norway
| | - Gustavo Antonio de Souza
- Institute of Immunology and Centre for Immune Regulation, Oslo University Hospital, Oslo, Norway
- Department of Biochemistry, Universidade Federal Do Rio Grande Do Norte, Natal, Brazil
| | - Ebba Gløersen Müller
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway
- Division of Radiology and Nuclear Medicine, Department of Nuclear Medicine, Oslo University Hospital, Oslo, Norway
| | - James Patrick Connelly
- Division of Radiology and Nuclear Medicine, Department of Nuclear Medicine, Oslo University Hospital, Oslo, Norway
| | - Mona-Elisabeth Revheim
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway
- Division of Radiology and Nuclear Medicine, Department of Nuclear Medicine, Oslo University Hospital, Oslo, Norway
- The Intervention Centre, Oslo University Hospital, Oslo, Norway
| | - Bente Halvorsen
- Research Institute of Internal Medicine, Oslo University Hospital, Oslo, Norway
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Bjørnar Hassel
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway
- Department of Neurohabilitation, Oslo University Hospital, Oslo, Norway
- Norwegian Defence Research Establishment (FFI), Kjeller, Norway
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Galanaud D, Gupta R. MR Imaging for Acute Central Nervous System Pathologies and Presentations in Emergency Department. Magn Reson Imaging Clin N Am 2022; 30:371-381. [PMID: 35995468 DOI: 10.1016/j.mric.2022.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
Although evaluation of suspected stroke is a major driver of MRI use in the emergency department (ED), the exquisite contrast resolution and flexibility provided by MRI are valuable in the workup of a broad variety of acute neurologic complaints. This article provides an overview, focused primarily on "non-stroke" neurologic emergencies encountered in ED brain MRI that emergency radiologists should be familiar with.
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Affiliation(s)
- Damien Galanaud
- Department of Neuroradiology, Pitié Salpêtrière Hospital, 47 Boulevard de l'hopital, Paris 75013, France
| | - Rajiv Gupta
- Department of Radiology, Massachusetts General Hospital, 55 Fruit Street, Boston, MA 02114, USA.
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3
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Polvoy I, Qin H, Flavell RR, Gordon J, Viswanath P, Sriram R, Ohliger MA, Wilson DM. Deuterium Metabolic Imaging-Rediscovery of a Spectroscopic Tool. Metabolites 2021; 11:570. [PMID: 34564385 PMCID: PMC8470013 DOI: 10.3390/metabo11090570] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 08/18/2021] [Indexed: 01/31/2023] Open
Abstract
The growing demand for metabolism-specific imaging techniques has rekindled interest in Deuterium (2H) Metabolic Imaging (DMI), a robust method based on administration of a substrate (glucose, acetate, fumarate, etc.) labeled with the stable isotope of hydrogen and the observation of its metabolic fate in three-dimensions. This technique allows the investigation of multiple metabolic processes in both healthy and diseased states. Despite its low natural abundance, the short relaxation time of deuterium allows for rapid radiofrequency (RF) pulses without saturation and efficient image acquisition. In this review, we provide a comprehensive picture of the evolution of DMI over the course of recent decades, with a special focus on its potential clinical applications.
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Affiliation(s)
- Ilona Polvoy
- Department of Radiology and Biomedical Imaging, University of California, 185 Berry St., San Francisco, CA 94158, USA; (I.P.); (H.Q.); (R.R.F.); (J.G.); (P.V.); (R.S.); (M.A.O.)
| | - Hecong Qin
- Department of Radiology and Biomedical Imaging, University of California, 185 Berry St., San Francisco, CA 94158, USA; (I.P.); (H.Q.); (R.R.F.); (J.G.); (P.V.); (R.S.); (M.A.O.)
| | - Robert R. Flavell
- Department of Radiology and Biomedical Imaging, University of California, 185 Berry St., San Francisco, CA 94158, USA; (I.P.); (H.Q.); (R.R.F.); (J.G.); (P.V.); (R.S.); (M.A.O.)
| | - Jeremy Gordon
- Department of Radiology and Biomedical Imaging, University of California, 185 Berry St., San Francisco, CA 94158, USA; (I.P.); (H.Q.); (R.R.F.); (J.G.); (P.V.); (R.S.); (M.A.O.)
| | - Pavithra Viswanath
- Department of Radiology and Biomedical Imaging, University of California, 185 Berry St., San Francisco, CA 94158, USA; (I.P.); (H.Q.); (R.R.F.); (J.G.); (P.V.); (R.S.); (M.A.O.)
| | - Renuka Sriram
- Department of Radiology and Biomedical Imaging, University of California, 185 Berry St., San Francisco, CA 94158, USA; (I.P.); (H.Q.); (R.R.F.); (J.G.); (P.V.); (R.S.); (M.A.O.)
| | - Michael A. Ohliger
- Department of Radiology and Biomedical Imaging, University of California, 185 Berry St., San Francisco, CA 94158, USA; (I.P.); (H.Q.); (R.R.F.); (J.G.); (P.V.); (R.S.); (M.A.O.)
- Department of Radiology, Zuckerberg San Francisco General Hospital, San Francisco, CA 94110, USA
| | - David M. Wilson
- Department of Radiology and Biomedical Imaging, University of California, 185 Berry St., San Francisco, CA 94158, USA; (I.P.); (H.Q.); (R.R.F.); (J.G.); (P.V.); (R.S.); (M.A.O.)
- Department of Radiology and Biomedical Imaging, University of California, 505 Parnassus Ave, San Francisco, CA 94143, USA
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Gajdošík M, Landheer K, Swanberg KM, Adlparvar F, Madelin G, Bogner W, Juchem C, Kirov II. Hippocampal single-voxel MR spectroscopy with a long echo time at 3 T using semi-LASER sequence. NMR IN BIOMEDICINE 2021; 34:e4538. [PMID: 33956374 PMCID: PMC10874619 DOI: 10.1002/nbm.4538] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 04/01/2021] [Accepted: 04/19/2021] [Indexed: 06/12/2023]
Abstract
The hippocampus is one of the most challenging brain regions for proton MR spectroscopy (MRS) applications. Moreover, quantification of J-coupled species such as myo-inositol (m-Ins) and glutamate + glutamine (Glx) is affected by the presence of macromolecular background. While long echo time (TE) MRS eliminates the macromolecules, it also decreases the m-Ins and Glx signal and, as a result, these metabolites are studied mainly with short TE. Here, we investigate the feasibility of reproducibly measuring their concentrations at a long TE of 120 ms, using a semi-adiabatic localization by adiabatic selective refocusing (sLASER) sequence, as this sequence was recently recommended as a standard for clinical MRS. Gradient offset-independent adiabatic refocusing pulses were implemented, and an optimal long TE for the detection of m-Ins and Glx was determined using the T2 relaxation times of macromolecules. Metabolite concentrations and their coefficients of variation (CVs) were obtained for a 3.4-mL voxel centered on the left hippocampus on 3-T MR systems at two different sites with three healthy subjects (aged 32.5 ± 10.2 years [mean ± standard deviation]) per site, with each subject scanned over two sessions, and with each session comprising three scans. Concentrations of m-Ins, choline, creatine, Glx and N-acetyl-aspartate were 5.4 ± 1.5, 1.7 ± 0.2, 5.8 ± 0.3, 11.6 ± 1.2 and 5.9 ± 0.4 mM (mean ± standard deviation), respectively. Their respective mean within-session CVs were 14.5% ± 5.9%, 6.5% ± 5.3%, 6.0% ± 3.4%, 10.6% ± 6.2% and 3.5% ± 1.4%, and their mean within-subject CVs were 17.8% ± 18.2%, 7.5% ± 6.3%, 7.4% ± 6.4%, 12.4% ± 5.3% and 4.8% ± 3.0%. The between-subject CVs were 25.0%, 12.3%, 5.3%, 10.7% and 6.4%, respectively. Hippocampal long-TE sLASER single voxel spectroscopy can provide macromolecule-independent assessment of all major metabolites including Glx and m-Ins.
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Affiliation(s)
- Martin Gajdošík
- Center for Advanced Imaging Innovation and Research (CAIR), Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University Grossman School of Medicine, New York, NY, United States
- Department of Biomedical Engineering, Columbia University Fu Foundation School of Engineering and Applied Science, New York, NY, United States
| | - Karl Landheer
- Department of Biomedical Engineering, Columbia University Fu Foundation School of Engineering and Applied Science, New York, NY, United States
| | - Kelley M. Swanberg
- Department of Biomedical Engineering, Columbia University Fu Foundation School of Engineering and Applied Science, New York, NY, United States
| | - Fatemeh Adlparvar
- Center for Advanced Imaging Innovation and Research (CAIR), Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University Grossman School of Medicine, New York, NY, United States
| | - Guillaume Madelin
- Center for Advanced Imaging Innovation and Research (CAIR), Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University Grossman School of Medicine, New York, NY, United States
| | - Wolfgang Bogner
- High-Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Christoph Juchem
- Department of Biomedical Engineering, Columbia University Fu Foundation School of Engineering and Applied Science, New York, NY, United States
- Department of Radiology, Columbia University College of Physicians and Surgeons, New York, NY, United States
| | - Ivan I. Kirov
- Center for Advanced Imaging Innovation and Research (CAIR), Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University Grossman School of Medicine, New York, NY, United States
- Department of Neurology, New York University Grossman School of Medicine, New York, NY, United States
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Reuter G, Moïse M, Roll W, Martin D, Lombard A, Scholtes F, Stummer W, Suero Molina E. Conventional and advanced imaging throughout the cycle of care of gliomas. Neurosurg Rev 2021; 44:2493-2509. [PMID: 33411093 DOI: 10.1007/s10143-020-01448-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 11/18/2020] [Accepted: 11/23/2020] [Indexed: 10/22/2022]
Abstract
Although imaging of gliomas has evolved tremendously over the last decades, published techniques and protocols are not always implemented into clinical practice. Furthermore, most of the published literature focuses on specific timepoints in glioma management. This article reviews the current literature on conventional and advanced imaging techniques and chronologically outlines their practical relevance for the clinical management of gliomas throughout the cycle of care. Relevant articles were located through the Pubmed/Medline database and included in this review. Interpretation of conventional and advanced imaging techniques is crucial along the entire process of glioma care, from diagnosis to follow-up. In addition to the described currently existing techniques, we expect deep learning or machine learning approaches to assist each step of glioma management through tumor segmentation, radiogenomics, prognostication, and characterization of pseudoprogression. Thorough knowledge of the specific performance, possibilities, and limitations of each imaging modality is key for their adequate use in glioma management.
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Affiliation(s)
- Gilles Reuter
- Department of Neurosurgery, University Hospital of Liège, Liège, Belgium. .,GIGA-CRC In-vivo Imaging Center, ULiege, Liège, Belgium.
| | - Martin Moïse
- Department of Radiology, University Hospital of Liège, Liège, Belgium
| | - Wolfgang Roll
- Department of Nuclear Medicine, University Hospital of Münster, Münster, Germany
| | - Didier Martin
- Department of Neurosurgery, University Hospital of Liège, Liège, Belgium
| | - Arnaud Lombard
- Department of Neurosurgery, University Hospital of Liège, Liège, Belgium
| | - Félix Scholtes
- Department of Neurosurgery, University Hospital of Liège, Liège, Belgium.,Department of Neuroanatomy, University of Liège, Liège, Belgium
| | - Walter Stummer
- Department of Neurosurgery, University Hospital of Münster, Münster, Germany
| | - Eric Suero Molina
- Department of Neurosurgery, University Hospital of Münster, Münster, Germany
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6
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Concentration and effective T
2
relaxation times of macromolecules at 3T. Magn Reson Med 2020; 84:2327-2337. [DOI: 10.1002/mrm.28282] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 03/10/2020] [Accepted: 03/23/2020] [Indexed: 01/22/2023]
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7
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The value of magnetic resonance spectroscopy as a supplement to MRI of the brain in a clinical setting. PLoS One 2018; 13:e0207336. [PMID: 30440005 PMCID: PMC6237369 DOI: 10.1371/journal.pone.0207336] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 10/30/2018] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND There are different opinions of the clinical value of MRS of the brain. In selected materials MRS has demonstrated good results for characterisation of both neoplastic and non-neoplastic lesions. The aim of this study was to evaluate the supplemental value of MR spectroscopy (MRS) in a clinical setting. MATERIAL AND METHODS MRI and MRS were re-evaluated in 208 cases with a clinically indicated MRS (cases with uncertain or insufficient information on MRI) and a confirmed diagnosis. Both single voxel spectroscopy (SVS) and chemical shift imaging (CSI) were performed in 105 cases, only SVS or CSI in 54 and 49 cases, respectively. Diagnoses were grouped into categories: non-neoplastic disease, low-grade tumour, and high-grade tumour. The clinical value of MRS was considered very beneficial if it provided the correct category or location when MRI did not, beneficial if it ruled out suspected diseases or was more specific than MRI, inconsequential if it provided the same level of information, or misleading if it provided less or incorrect information. RESULTS There were 70 non-neoplastic lesions, 43 low-grade tumours, and 95 high-grade tumours. For MRI, the category was correct in 130 cases (62%), indeterminate in 39 cases (19%), and incorrect in 39 cases (19%). Supplemented with MRS, 134 cases (64%) were correct, 23 cases (11%) indeterminate, and 51 (25%) incorrect. Additional information from MRS was beneficial or very beneficial in 31 cases (15%) and misleading in 36 cases (17%). CONCLUSION In most cases MRS did not add to the diagnostic value of MRI. In selected cases, MRS may be a valuable supplement to MRI.
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8
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Magnetic Resonance Spectroscopy and its Clinical Applications: A Review. J Med Imaging Radiat Sci 2017; 48:233-253. [PMID: 31047406 DOI: 10.1016/j.jmir.2017.06.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Revised: 04/30/2017] [Accepted: 06/22/2017] [Indexed: 12/25/2022]
Abstract
In vivo NMR spectroscopy is known as magnetic resonance spectroscopy (MRS). MRS has been applied as both a research and a clinical tool in order to detect visible or nonvisible abnormalities. The adaptability of MRS allows a technique that can probe a wide variety of metabolic uses across different tissues. Although MRS is mostly applied for brain tissue, it can be used for detection, localization, staging, tumour aggressiveness evaluation, and tumour response assessment of breast, prostate, hepatic, and other cancers. In this article, the medical applications of MRS in the brain, including tumours, neural and psychiatric disorder studies, breast, prostate, hepatic, gastrointestinal, and genitourinary investigations have been reviewed.
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Brandão LA, Castillo M. Adult Brain Tumors: Clinical Applications of Magnetic Resonance Spectroscopy. Magn Reson Imaging Clin N Am 2017; 24:781-809. [PMID: 27742117 DOI: 10.1016/j.mric.2016.07.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Proton magnetic resonance spectroscopy (H-MRS) may be helpful in suggesting tumor histology and tumor grade and may better define tumor extension and the ideal site for biopsy compared with conventional magnetic resonance (MR) imaging. A multifunctional approach with diffusion-weighted imaging, perfusion-weighted imaging, and permeability maps, along with H-MRS, may enhance the accuracy of the diagnosis and characterization of brain tumors and estimation of therapeutic response. Integration of advanced imaging techniques with conventional MR imaging and the clinical history help to improve the accuracy, sensitivity, and specificity in differentiating tumors and nonneoplastic lesions.
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Affiliation(s)
- Lara A Brandão
- Clínica Felippe Mattoso, Av. Das Américas 700, sala 320, Barra da Tijuca, Rio de Janeiro 30112011, Brazil; Clínica IRM- Ressonância Magnética, Rua Capitão Salomão 44 Humaitá, Rio de Janeiro 22271040, Brazil.
| | - Mauricio Castillo
- Division of Neuroradiology, Department of Radiology, University of North Carolina School of Medicine, Room 3326, Old Infirmary Building, Manning Drive, Chapel Hill, NC 27599-7510, USA
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Lange T, Ko CW, Lai PH, Dacko M, Tsai SY, Buechert M. Simultaneous detection of valine and lactate using MEGA-PRESS editing in pyogenic brain abscess. NMR IN BIOMEDICINE 2016; 29:1739-1747. [PMID: 27779348 DOI: 10.1002/nbm.3660] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 09/23/2016] [Accepted: 09/23/2016] [Indexed: 05/06/2023]
Abstract
Valine and lactate have been recognized as important metabolic markers to diagnose brain abscess by means of MRS. However, in vivo unambiguous detection and quantification is hampered by macromolecular contamination. In this work, MEGA-PRESS difference editing of valine and lactate is proposed. The method is validated in vitro and applied for quantitative in vivo experiments in one healthy subject and two brain abscess patients. It is demonstrated that with this technique the overlapping lipid signal can be reduced by more than an order of magnitude and thus the robustness of valine and lactate detection in vivo can be enhanced. Quantification of the two abscess MEGA-PRESS spectra yielded valine/lactate concentration ratios of 0.10 and 0.27. These ratios agreed with the concentration ratios determined from concomitantly acquired short-TE PRESS data and were in line with literature values. The quantification accuracy of lactate (as measured with Cramér-Rao lower bounds in LCModel processing) was better for MEGA-PRESS than for short-TE PRESS in all acquired in vivo datasets. The Cramér-Rao lower bounds of valine were only better for MEGA-PRESS in one of the two abscess cases, while in the other case coediting of isoleucine confounded the quantification in the MEGA-PRESS analysis. MEGA-PRESS and short-TE PRESS should be combined for unambiguous quantification of amino acids in abscess measurements. Simultaneous valine/lactate MEGA-PRESS editing might benefit the distinction of brain abscesses from tumors, and further categorization of bacteria with reasonable sensitivity and specificity.
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Affiliation(s)
- Thomas Lange
- Department of Radiology, Medical Physics, Medical Center-University of Freiburg, Freiburg, Germany
| | - Cheng-Wen Ko
- Department of Computer Science and Engineering, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Ping-Hong Lai
- Department of Radiology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Michael Dacko
- Department of Radiology, Medical Physics, Medical Center-University of Freiburg, Freiburg, Germany
| | - Shang-Yueh Tsai
- Graduate Institute of Applied Physics, National Chengchi University, Taipei, Taiwan
- Research Center for Mind, Brain and Learning, National Chengchi University, Taipei, Taiwan
| | - Martin Buechert
- Department of Radiology, Medical Physics, Medical Center-University of Freiburg, Freiburg, Germany
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Abstract
Magnetic resonance spectroscopy (MRS) is a noninvasive functional technique to evaluate the biochemical behavior of human tissues. This property has been widely used in assessment and therapy monitoring of brain tumors. MRS studies can be implemented outside the brain, with successful and promising results in the evaluation of prostate and breast cancer, although still with limited reproducibility. As a result of technical improvements, malignancies of the musculoskeletal system and abdominopelvic organs can benefit from the molecular information that MRS provides. The technical challenges and main applications in oncology of (1)H MRS in a clinical setting are the focus of this review.
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Abstract
OBJECT
Brain abscesses could lead to cerebral symptoms through tissue destruction, edema, changes in brain architecture, and increased intracranial pressure. However, the possibility that the pus itself could contribute to symptoms has received little attention. Brain abscesses are areas of tissue destruction, proteolysis, and formation of free amino acids, which are energy substrates for bacteria and possible sources of ammonia. Ammonia is neurotoxic, may cause brain edema, and could contribute to the symptoms of brain abscesses.
METHODS
The authors analyzed the extracellular phase of pus from 14 patients with brain abscesses with respect to ammonia and amino acids. For comparison, CSF from 10 patients undergoing external ventricular drainage was included. The ammonia-forming ability of Streptococcus intermedius and Staphylococcus aureus, two common microbial isolates in brain abscesses, was studied in vitro.
RESULTS
In brain abscesses ammonia was 15.5 mmol/L (median value; range 1.7–69.2 mmol/L). In CSF ammonia was 29 μmol/L (range 17–55 μmol/L; difference from value in pus: p < 0.001). The total concentration of amino acids in brain abscesses was 1.12–16 times higher than the ammonia concentration (p = 0.011). The median glucose value in pus was 0 mmol/L (range 0–2.1 mmol/L), lactate was 21 mmol/L (range 3.3–26.5 mmol/L), and pH was 6.8 (range 6.2–7.3). In vitro, S. intermedius and S. aureus formed ammonia at 6–7 mmol/L in 24 hours when incubated with 20 proteinogenic amino acids plus g-aminobutyric acid (GABA), taurine, and glutathione at 1 mmol/L.
CONCLUSIONS
Intracerebral abscesses contain toxic levels of ammonia. At the concentrations found in pus, ammonia could contribute to the brain edema and the symptoms of brain abscesses.
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Affiliation(s)
| | | | - Bjørnar Hassel
- 2Complex Neurology and Neurohabilitation, Oslo University Hospital, Oslo; and
- 3Norwegian Defence Research Establishment (FFI), Kjeller, Norway
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Villanueva-Meyer JE, Cha S. From Shades of Gray to Microbiologic Imaging: A Historical Review of Brain Abscess Imaging:RSNA Centennial Article. Radiographics 2015. [DOI: 10.1148/rg.2015140297] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Goto Y, Ebisu T, Mineura K. Abscess formation within a cerebellar metastasis: Case report and literature review. Int J Surg Case Rep 2015; 10:59-64. [PMID: 25799962 PMCID: PMC4429840 DOI: 10.1016/j.ijscr.2015.03.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 03/06/2015] [Accepted: 03/07/2015] [Indexed: 12/01/2022] Open
Abstract
We experienced a patient with a brain abscess within a cerebellar metastasis. A brain abscess within a brain neoplasm is a small entity, and only five cases harboring an abscess within a metastatic brain tumor have been reported to date. Surgical procedures for brain abscesses and brain tumors are completely different; however, even today, it is difficult to differentiate a brain abscess from a necrotic brain tumor in advance. Differentiation between the two is important due to different methods of management; preoperative assumption of the possible coexistence of both types of lesions could lead to a good outcome when we encounter a lesion which has both the imaging characteristics. The preferred treatment of a case with both an abscess and a brain metastasis is complete surgical removal of the tumor and targeted antibiotic therapy for the abscess. The present case highlights the importance of considering coexisting diseases prior to surgery.
Introduction The managements of brain abscesses and brain tumors including brain metastases differ greatly, especially in terms of surgical procedures. Therefore, differentiating between the two is essential for assuring optimal treatment. However, on rare occasion, these two lesions coexist. Only five cases with both a brain tumor and an abscess have thus, far been reported. We experienced a patient with a brain abscess within a cerebellar metastasis. Case presentation A middle-aged man receiving treatment for bile duct cancer presented with headache and nausea. Computed tomography (CT) and magnetic resonance (MR) imaging revealed two lesions, one in each cerebellar hemisphere. Although these lesions appeared to be brain metastases, the right lesion showed high intensity on diffusion-weighted images (DWI), and magnetic resonance spectroscopy (MRS) findings suggested an abscess. Surgical puncture of the lesion identified it as a brain abscess histologically, and we thus, administered antibiotics. However, since the lesion grew, we performed a second surgery for removal, which histopathologically the lesion to be a well-differentiated adenocarcinoma. The final diagnosis was an abscess within a cerebellar metastasis. Discussion/conclusion Modern diagnostic tools such as DWI and MRS are reportedly reliable for differentiating brain tumors from brain abscesses, though they are not specific in cases with both lesions. The present case highlights the importance of considering coexisting diseases prior to surgery when we encounter a lesion which has the imaging characteristics of both a tumor and an abscess. The patient may have a better outcome if, preoperatively, surgeons take into consideration the possibility of the coexistence of a brain tumor and a brain abscess.
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Affiliation(s)
- Yukihiro Goto
- Department of Neurosurgery, Kyoto Prefectural University Graduate School of Medicine Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
| | - Toshihiko Ebisu
- Department of Neurosurgery, Nantan General Hospital Yagi-cho, Yagiueno 25, Nantan-city, Kyoto 629-0197, Japan
| | - Katsuyoshi Mineura
- Department of Neurosurgery, Kyoto Prefectural University Graduate School of Medicine Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan
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Grand S, Pasteris C, Attye A, Le Bas JF, Krainik A. The different faces of central nervous system metastases. Diagn Interv Imaging 2014; 95:917-31. [DOI: 10.1016/j.diii.2014.06.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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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] [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.
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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
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17
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High extracellular concentration of excitatory amino acids glutamate and aspartate in human brain abscess. Neurochem Int 2014; 69:41-7. [DOI: 10.1016/j.neuint.2014.03.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 02/25/2014] [Accepted: 03/02/2014] [Indexed: 11/17/2022]
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18
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19
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20
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Rao PJ, Jyoti R, Mews PJ, Desmond P, Khurana VG. Preoperative magnetic resonance spectroscopy improves diagnostic accuracy in a series of neurosurgical dilemmas. Br J Neurosurg 2013; 27:646-53. [PMID: 23461752 DOI: 10.3109/02688697.2013.771724] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECT The purpose of this study was to evaluate the usefulness of preoperative magnetic resonance spectroscopy (MRS) in neurosurgical patients with diagnostically challenging intracranial lesions. METHODS Included in this study are twenty-three consecutive patients presenting to the neurosurgery service with diagnostically challenging intracranial lesions and who were investigated by conventional MR imaging and proton ((1)H) MRS, followed by surgery with subsequent histopathological diagnosis. An experienced neuroradiologist (RJ) blinded to the final histopathology evaluated the imaging studies retrospectively. Provisional diagnoses based on preoperative clinical and conventional MR data versus preoperative MRS data were compared with definitive histopathological diagnoses. RESULTS Compared with preoperative clinical and conventional MR data, (1)H MRS improved the accuracy of MR imaging from 60.9% to 83%. We found (1)H MRS reliably distinguished between abscess and high-grade tumour, and between high-grade glioma and low-grade glioma, but was not able to reliably distinguish between recurrent glioma and radiation necrosis. In 12/23 cases (52%) the (1)H MRS findings positively altered our clinical management. Two representative cases are presented. CONCLUSIONS Our study supports a beneficial role for (1)H MRS in certain diagnostic intracranial dilemmas presenting to neurosurgeons. The information gleaned from preoperative (1)H MRS can be a useful adjunct to clinical and conventional MR imaging data in guiding the management of patients with intracranial pathologies, particularly high-grade tumour versus abscess, and high-grade versus low-grade glioma. Further larger prospective studies are needed to clearly define the utility of (1)H MRS in diagnostically challenging intracranial lesions in neurosurgery.
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Affiliation(s)
- P J Rao
- Department of Neurosurgery, The Canberra Hospital, Garran, ACT, Australia
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21
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Hsu SH, Chou MC, Ko CW, Hsu SS, Lin HS, Fu JH, Wang PC, Pan HB, Lai PH. Proton MR spectroscopy in patients with pyogenic brain abscess: MR spectroscopic imaging versus single-voxel spectroscopy. Eur J Radiol 2013; 82:1299-307. [PMID: 23453705 DOI: 10.1016/j.ejrad.2013.01.032] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Revised: 01/28/2013] [Accepted: 01/29/2013] [Indexed: 10/27/2022]
Abstract
PURPOSE Single-voxel spectroscopy (SVS) has been the gold standard technique to diagnose the pyogenic abssess. Two-dimensional magnetic resonance spectroscopic imaging (MRSI) is able to provide spatial distribution of metabolic concentration, and is potentially more suitable for differential diagnosis between abscess and necrotic tumors. Therefore, the purpose of this study was to evaluate the equivalence of MRSI and SVS in the detection of the metabolites in pyogenic brain abscesses. MATERIALS AND METHODS Forty-two patients with pyogenic abscesses were studied by using both SVS and MRSI methods. Two neuroradiologists reviewed the MRS data independently. A κ value was calculated to express inter-reader agreement of the abscesses metabolites, and a correlation coefficient was calculated to show the similarity of two spectra. After consensus judgment of two readers, the binary value of metabolites of pyogenic abscesses (presence or absence) was compared between SVS and MRSI. RESULTS The consistency of spectral interpretation of the two readers was very good (κ ranged from 0.95 to 1), and the similarity of two spectra was also very high (cc=0.9±0.05). After consensus judgment of two readers, the sensitivities of MRSI ranged from 91% (acetate) to 100% (amino acids, succinate, lactate, lipid), and the specificities of MRSI were 100% for detecting all metabolites with SVS as reference. CONCLUSION SVS and MRSI provide similar metabolites in the cavity of pyogenic brain abscess. With additional metabolic information of cavity wall and contralateral normal-appearing brain tissue, MRSI would be a more suitable technique to differentiate abscesses from necrotic tumors.
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Affiliation(s)
- Shuo-Hsiu Hsu
- Department of Radiology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan, ROC.
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Bertholdo D, Watcharakorn A, Castillo M. Brain proton magnetic resonance spectroscopy: introduction and overview. Neuroimaging Clin N Am 2013; 23:359-80. [PMID: 23928194 DOI: 10.1016/j.nic.2012.10.002] [Citation(s) in RCA: 115] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Magnetic resonance (MR) spectroscopy offers a noninvasive means of assessing in vivo brain metabolites that shed light on cellular concentrations, cell function and dysfunction, cellular energetics, presence of ischemia, and presence of necrosis, among others. Studies obtained at higher field strengths are evolving toward sampling of smaller tissue volumes, greater signal-to-noise ratio, and higher metabolic spatial resolution. This article discusses the usefulness, from the clinical standpoint, of MR spectroscopy in various disorders. However, to be valid and significant the results of MR spectroscopy should always be correlated with their imaging counterparts.
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Affiliation(s)
- Débora Bertholdo
- University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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23
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Rath TJ, Hughes M, Arabi M, Shah GV. Imaging of Cerebritis, Encephalitis, and Brain Abscess. Neuroimaging Clin N Am 2012; 22:585-607. [DOI: 10.1016/j.nic.2012.04.002] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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24
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Julià-Sapé M, Coronel I, Majós C, Candiota AP, Serrallonga M, Cos M, Aguilera C, Acebes JJ, Griffiths JR, Arús C. Prospective diagnostic performance evaluation of single-voxel 1H MRS for typing and grading of brain tumours. NMR IN BIOMEDICINE 2012; 25:661-73. [PMID: 21954036 DOI: 10.1002/nbm.1782] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Revised: 07/12/2011] [Accepted: 07/14/2011] [Indexed: 05/31/2023]
Abstract
The purpose of this study was to evaluate whether single-voxel (1)H MRS could add useful information to conventional MRI in the preoperative characterisation of the type and grade of brain tumours. MRI and MRS examinations from a prospective cohort of 40 consecutive patients were analysed double blind by radiologists and spectroscopists before the histological diagnosis was known. The spectroscopists had only the MR spectra, whereas the radiologists had both the MR images and basic clinical details (age, sex and presenting symptoms). Then, the radiologists and spectroscopists exchanged their predictions and re-evaluated their initial opinions, taking into account the new evidence. Spectroscopists used four different systems of analysis for (1)H MRS data, and the efficacy of each of these methods was also evaluated. Information extracted from (1)H MRS significantly improved the radiologists' MRI-based characterisation of grade IV tumours (glioblastomas, metastases, medulloblastomas and lymphomas) in the cohort [area under the curve (AUC) in the MRI re-evaluation 0.93 versus AUC in the MRI evaluation 0.85], and also of the less malignant glial tumours (AUC in the MRI re-evaluation 0.93 versus AUC in the MRI evaluation 0.81). One of the MRS analysis systems used, the INTERPRET (International Network for Pattern Recognition of Tumours Using Magnetic Resonance) decision support system, outperformed the others, as well as being better than the MRI evaluation for the characterisation of grade III astrocytomas. Thus, preoperative MRS data improve the radiologists' performance in diagnosing grade IV tumours and, for those of grade II-III, MRS data help them to recognise the glial lineage. Even in cases in which their diagnoses were not improved, the provision of MRS data to the radiologists had no negative influence on their predictions.
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Affiliation(s)
- Margarida Julià-Sapé
- Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Cerdanyola del Vallès, Spain
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25
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Dusak A, Hakyemez B, Kocaeli H, Bekar A. Magnetic resonance spectroscopy findings of pyogenic, tuberculous, and Cryptococcus intracranial abscesses. Neurochem Res 2011; 37:233-7. [PMID: 22002661 DOI: 10.1007/s11064-011-0622-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Revised: 09/11/2011] [Accepted: 09/27/2011] [Indexed: 12/01/2022]
Abstract
Proton magnetic resonance spectroscopy (MRS) complements conventional methods used to differentiate intracranial cystic lesions. We report MRS findings of three cases that were diagnosed as pyogenic, tuberculous, and Cryptococcus abscesses before instituting any medical or surgical therapy. The pyogenic brain abscess had typical specific spectral findings (i.e., the demonstration of amino acids). Lactate and lipid peaks were visible in the tuberculous abscess. Cryptococcus neoformans can appear differently in different brain regions, which may lead to different spectral findings.
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Affiliation(s)
- Abdurrahim Dusak
- Department of Radiology, University of Rochester Medical Center, 601 Elmwood Avenue, Rochester, NY 14642, USA.
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26
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Schneider JF, Hanquinet S, Severino M, Rossi A. MR imaging of neonatal brain infections. Magn Reson Imaging Clin N Am 2011; 19:761-75; vii-viii. [PMID: 22082736 DOI: 10.1016/j.mric.2011.08.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Infections of the brain in the postnatal period differ from those in older children as a result of a combination of distinct epidemiologic factors in general, and immaturity of neonatal brain and immunologic host response in particular. It has been recognized that clinical and neurologic signs are often nonspecific, sometimes scarce, and seldom correlate with the extent of neuroimaging findings, thus warranting an early MR imaging examination in the course of the disease, enabling rapid therapy institution and better clinical outcome. This article reviews most of postnatal pathogen agents involved in neonatal brain infections, related physiopathology, and neuroimaging findings.
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Affiliation(s)
- Jacques F Schneider
- Department of Pediatric Radiology, University Children's Hospital Basel, UKBB, Spitalstrasse 33, 4056 Basel, Switzerland.
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27
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Bernabeu A, López-Celada S, Alenda C, Baño E. Epidermoid cyst with a metabolite pattern mimicking a brain abscess. A magnetic resonance spectroscopy study. J Neuroimaging 2011; 23:145-8. [PMID: 21699604 DOI: 10.1111/j.1552-6569.2011.00608.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Intracranial epidermal cysts are benign uncommon lesions. Such lesions arise from an inclusion of an ectodermal element during neural tube closure, in which dermal elements become trapped in the suture line, diploe, meninges, or scalp. Reports have extensively demonstrated the typical magnetic resonance (MR) spectra with the presence of large lactate signals with a virtual absence of healthy brain metabolites. METHODS A 20-year-old male patient with a parietal lobe brain lesion was studied by magnetic resonance imaging and magnetic resonance spectroscopy in a 1.5-T Philips scanner. RESULTS The lesion presented atypical MR spectra with presence of alanine (1.46 ppm), lactate (1.31 ppm), and amino acids such as valine, isoleucine (0.97 ppm), and glicine (3.52 ppm). No evidence of normal parenchyma tissue metabolites (N-acetylaspartate, creatine, and choline) or succinate and acetate signals was observed. This spectral pattern was unexpected being proposed the differential diagnosis of brain abscess versus epidermoid cyst. Finally, surgical total excision biopsy confirmed the diagnosis of epidermal cyst. CONCLUSIONS In this report, we describe a case of an epidermal cyst with an unusual metabolic pattern observed by magnetic resonance spectroscopy mimicking a brain abscess.
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Affiliation(s)
- Angela Bernabeu
- Department of Magnetic Resonance, Inscanner SL-Erescanner Salud Ute, Hospital General Universitario de Alicante, Alicante, Spain.
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28
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Schneider JF. Neonatal brain infections. Pediatr Radiol 2011; 41 Suppl 1:S143-8. [PMID: 21523589 DOI: 10.1007/s00247-011-2041-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2010] [Revised: 12/30/2010] [Accepted: 01/21/2011] [Indexed: 11/30/2022]
Abstract
Infections of the brain in the neonatal period differ considerably from infections in the older child, due to a variety of age-specific factors that are related not only to the child, but also to the mother, and to specific pathogenic organisms. It has been recognized that clinical and neurological signs are often non-specific, sometimes scarce, and seldom correlate with the extent of neuroimaging findings, thus warranting early imaging to ensure timely therapy and improved outcome.
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Affiliation(s)
- Jacques F Schneider
- Department of Paediatric Radiology, University Children's Hospital Basel, UKBB, Roemergasse 8, 4058 Basel, Switzerland.
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29
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Menon S, Bharadwaj R, Chowdhary AS, Kaundinya DV, Palande DA. Utility of in vitro proton magnetic resonance spectroscopy in aetiological characterisation of brain abscesses. Indian J Med Microbiol 2011; 28:348-53. [PMID: 20966567 DOI: 10.4103/0255-0857.71832] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
PURPOSE Brain abscesses often present an aetiological dilemma. Microscopy is insensitive and culture techniques are time consuming. Hence, a new rapid technique in vitro Proton Magnetic Resonance Spectroscopy (1HMRS) was evaluated for its usefulness in the identification of aetiology of brain abscesses. MATERIALS AND METHODS A total of 39 pus specimens from brain abscesses were subjected to in vitro 1HMRS. These pus specimens were also processed by conventional culture methods. The spectral patterns generated by in vitro 1HMRS were further correlated with culture results. RESULTS Pus specimens which showed the presence of anaerobes on culture revealed the presence of multiplet at 0.9 ppm (100%), lactate-lipid at 1.3 ppm (100%), acetate at 1.92 ppm (100%) and succinate at 2.4 ppm (75%). Pus specimens that revealed the presence of facultative anaerobes on culture showed a pattern B, i.e., the presence of lactate-lipid at 1.3 ppm (100%), acetate at 1.92 ppm (88.88%) along with the multiplet at 0.9 ppm (100%). Pattern C was seen in aerobic infection which showed the presence of lactate-lipid at 1.3 ppm (100%) along with the multiplet at 0.9 ppm. Pus from two tuberculous abscesses showed the complete absence of multiplet at 0.9 ppm. CONCLUSIONS We observed in this study that it was possible to differentiate bacterial and tuberculous brain abscesses using in vitro 1HMRS. Further, it was also possible to distinguish between aerobic and anaerobic brain abscesses on the basis of spectral patterns. In vitro 1HMRS of fungal and actinomycotic brain abscess are also presented for its unusual spectra.
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Affiliation(s)
- S Menon
- Department of Microbiology, Grant Medical College & Sir J.J. Hospital, Mumbai, India.
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30
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Majós C, Bruna J, Julià-Sapé M, Cos M, Camins A, Gil M, Acebes JJ, Aguilera C, Arús C. Proton MR spectroscopy provides relevant prognostic information in high-grade astrocytomas. AJNR Am J Neuroradiol 2010; 32:74-80. [PMID: 21030477 DOI: 10.3174/ajnr.a2251] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE There is a large range of survival times in patients with HGA that can only be partially explained by histologic grade and clinical aspects. This study aims to retrospectively assess the predictive value of single-voxel (1)H-MRS regarding survival in HGA. MATERIALS AND METHODS Pretreatment (1)H-MRS in 187 patients with HGA produced 180 spectra at STE (30 ms) and 182 at LTE (136 ms). Patients were dichotomized into 2 groups according to survival better or worse than the median. The spectra of the 2 groups were compared using the Mann-Whitney U test. The points on the spectrum with the most significant differences were selected for discriminating patients with good and poor prognosis. Thresholds were defined with ROC curves, and survival was analyzed by using the Kaplan-Meier method and the Cox proportional hazards model. RESULTS Four points on the spectrum showed the most significant differences: 0.98 and 3.67 ppm at STE; and 0.98 and 1.25 ppm at LTE (P between <.001 and .011). These points were useful for stratifying 2 prognostic groups (P between <.001 and .003, Kaplan-Meier). The Cox forward stepwise model selected 3 spectroscopic variables: the intensity values of the points 3.67 ppm at STE (hazard ratio, 2.132; 95% CI, 1.504-3.023), 0.98 ppm at LTE (hazard ratio, 0.499; 95% CI, 0.339-0.736), and 1.25 ppm at LTE (hazard ratio, 0.574; 95% CI, 0.368-0.897). CONCLUSIONS (1)H-MRS is of value in predicting the length of survival in patients with HGA and could be used to stratify prognostic groups.
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Affiliation(s)
- C Majós
- Department of Radiology, Institut de Diagnòstic per Imatge, Centre Bellvitge, Hospital Universitari de Bellvitge, L'Hospitalet de Llobregat, Spain.
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31
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[Value of MR spectroscopy in infectious and inflammatory brain diseases]. Radiologe 2010; 50:784-90. [PMID: 20924742 DOI: 10.1007/s00117-009-1949-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Proton magnetic resonance spectroscopy (MRS) is a non-invasive method for measuring cerebral metabolite concentrations in various pathologic conditions. This review discusses the MRS findings in the most common infectious and inflammatory brain diseases.
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32
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Mortimer A, O'Leary S, Bradley M, Renowden SA. Pitfalls in the discrimination of cerebral abscess from tumour using diffusion-weighted MRI. Clin Radiol 2010; 65:488-92. [PMID: 20451017 DOI: 10.1016/j.crad.2009.12.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2009] [Revised: 12/05/2009] [Accepted: 12/07/2009] [Indexed: 01/22/2023]
Affiliation(s)
- A Mortimer
- Severn School of Radiology, Bristol, UK.
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33
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Role of diffusion tensor imaging metrics and in vivo proton magnetic resonance spectroscopy in the differential diagnosis of cystic intracranial mass lesions. Magn Reson Imaging 2009; 27:198-206. [DOI: 10.1016/j.mri.2008.06.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2008] [Revised: 06/13/2008] [Accepted: 06/17/2008] [Indexed: 12/14/2022]
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Papanagiotou P, Grunwald IQ, Farmakis G, Hartmann KM, Politi M, Roth C, Reith W. [Magnetic resonance spectroscopy for inflammatory brain diseases]. Radiologe 2008; 48:582-7. [PMID: 18504536 DOI: 10.1007/s00117-008-1696-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Magnetic resonance spectroscopy (MRS) is a non-invasive method for investigation of cerebral metabolite concentrations in various pathologic conditions. The clinical use of MRS for intracranial disorders is well established. In this review the characteristic MRS findings for the most important inflammatory brain diseases will be discussed.
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Affiliation(s)
- P Papanagiotou
- Klinik für Diagnostische und Interventionelle Neuroradiologie, Universitätsklinikum des Saarlandes, Kirrberger Strabe 1, 66421, Homburg/Saar.
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35
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Sorrell TC, Himmelreich U. The role of nuclear magnetic resonance in medical mycology. CURRENT FUNGAL INFECTION REPORTS 2008. [DOI: 10.1007/s12281-008-0022-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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36
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Liu HS, Chung HW, Juan CJ, Tsai SY, Wang CY, Chan CC, Huang GS, Chou MC, Lee CS, Ko CW, Cho NY, Chen CY. Anomalous J-modulation effects on amino acids in clinical 3T MR spectroscopy. AJNR Am J Neuroradiol 2008; 29:1644-8. [PMID: 18768734 DOI: 10.3174/ajnr.a1131] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The signal-intensity loss from anomalous J-modulation effects due to chemical-shift displacement was investigated on amino acid groups (alanine, valine, leucine, and isoleucine) at 3T by using point-resolved (1)H spectroscopy in patients with brain abscess and phantom experiments. With a larger chemical shift between methyl and methine resonances, alanine shows a greater effect of signal-intensity cancellation compared with other amino acids around 0.9 ppm, resulting in noninverted doublets at a TE of 144 ms.
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Affiliation(s)
- H-S Liu
- Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan
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Wiener E, Zanetti M, Hodler J, Pfirrmann CWA. Lactate and T (2) measurements of synovial aspirates at 1.5 T: differentiation of septic from non-septic arthritis. Skeletal Radiol 2008; 37:743-8. [PMID: 18523767 DOI: 10.1007/s00256-008-0505-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2008] [Revised: 04/09/2008] [Accepted: 04/10/2008] [Indexed: 02/02/2023]
Abstract
OBJECTIVE The aim of this study was to differentiate septic from non-septic arthritis by measuring lactate concentration with (1)H magnetic resonance spectroscopy (HMRS) and by estimating total protein content with the assessment of T (2) values. MATERIALS AND METHODS In 30 patients with acute arthritis, synovial fluid was aspirated. Lactate concentrations were analyzed with single voxel HMRS at 1.5 T. T (2) relaxation times were mapped with a multi-spin echo sequence. All samples underwent microbiological testing and routine laboratory analysis to quantify lactate concentration and total protein content. Values obtained in septic and non-septic arthritis were compared with a Mann-Whitney U test. RESULTS Synovial fluid from patients with septic arthritis (n = 10) had higher concentrations of lactate (11.4 +/- 4.0 mmol/L) and higher total protein content (51.8 +/- 10.7 g/L) than fluid obtained in non-septic arthritis (n = 20; 5.2 +/- 1.1 mmol/L and 40.4 +/- 6.9 g/L, respectively, p < 0.001 and <0.01, respectively). Measured lactate concentrations and T (2) relaxation times (as an indicator of total protein content) were moderately correlated to laboratory-confirmed lactate concentration (r (2) = 0.71) and total protein content (r (2) = 0.73). Markedly increased lactate concentrations (>6 mmol/L) in combination with low T (2) values (<550 ms) identify septic arthritis with a sensitivity of 70% and a specificity of 89%. CONCLUSION Spectroscopic measurements of lactate concentration in combination with the estimation of protein content using T (2) may be of value in the differentiation of septic from non-septic arthritis.
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Affiliation(s)
- Edzard Wiener
- Department of Radiology, Orthopedic University Hospital Balgrist, Forchstrasse 340, CH-8008, Zurich, Switzerland.
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Kapsalaki EZ, Gotsis ED, Fountas KN. The role of proton magnetic resonance spectroscopy in the diagnosis and categorization of cerebral abscesses. Neurosurg Focus 2008; 24:E7. [DOI: 10.3171/foc/2008/24/6/e7] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
✓ Despite recent advances in neuroimaging, differentiation between cerebral abscesses and necrotic tumors with ring-type contrast enhancement can be puzzling at times. The introduction of advanced imaging techniques, such as diffusion-weighted imaging, has contributed to the identification of cerebral abscesses. However, differentiation may be impossible with imaging only. In this review the authors evaluate the role of proton magnetic resonance (MR) spectroscopy in differentiating between cerebral abscesses and necrotic tumors and address the spectral characteristics of intracranial abscesses. A large number of metabolites not detected in the normal brain spectra may be detected and give valuable information regarding the nature of the abscesses. Proton MR spectroscopy is a safe, noninvasive diagnostic modality, which could significantly increase the accuracy and specificity of conventional MR imaging in differentiating between malignant tumors and cerebral abscesses and provide valuable information regarding the cause of an abscess, as well as, its response to the chosen treatment.
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Affiliation(s)
| | - Efstathios D. Gotsis
- 2Encephalos-Euromedica, Advanced Diagnostic and Research Institute, Athens, Greece
| | - Kostas N. Fountas
- 3Neurosurgery, University Hospital of Larissa, University of Thessaly, School of Medicine, Larissa, Greece; and
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(1)H MR spectroscopy of inflammation, infection and ischemia of the brain. Eur J Radiol 2008; 67:250-257. [PMID: 18407447 DOI: 10.1016/j.ejrad.2008.02.033] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2008] [Accepted: 02/27/2008] [Indexed: 11/21/2022]
Abstract
Different pathologic patterns in multiple sclerosis (MS) are reflected by alterations of metabolites in (1)H MR spectroscopy of the brain. Elevated choline (Cho), lactate (Lac), lipids and macromolecules are reliable markers for acute demyelination regardless of the clinical entity (also in acute disseminated encephalomyelitis). N-acetyl-aspartate (NAA) is a suitable marker for neuronal integrity. It is reduced in acute MS lesions and in normal appearing white matter, even distant to acute and chronic-lesions. Recovery from reduced NAA levels to subnormal values during remyelination, and varying time courses of NAA in normal appearing white matter during relapsing remitting disease indicate the value of this spectroscopic marker for monitoring activity and recovery. Inositol (Ins) is increased in chronic MS lesions being a marker for astrocytic gliosis. In viral disease, Cho and Ins are always increased, whereas a reduction of NAA mostly reflects an advanced or a detoriated clinical state. In bacterial brain abscesses, numerous amino acids, lipids and Lac can be elevated. In ischemia, especially the Lac/NAA in comparison with perfusion and diffusion weighted imaging seems to be a new measure for areas of metabolic need, and may help to better characterise the penumbra of the stroke and the final infarct size.
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Proton magnetic resonance spectroscopy and diffusion-weighted imaging in intracranial cystic mass lesions. ACTA ACUST UNITED AC 2008; 68 Suppl 1:S25-36. [PMID: 17963918 DOI: 10.1016/j.surneu.2007.07.080] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2006] [Accepted: 07/26/2007] [Indexed: 11/20/2022]
Abstract
BACKGROUND The differential diagnosis of various intracranial cystic lesions is sometimes difficult on the basis of CT or MRI findings. Our objective was to evaluate (1)H MRS and DWI in the differential diagnosis of these lesions and in comparison with conventional MRI. METHODS Fifty patients with intracranial cystic lesions (21 pyogenic abscesses, 23 tumor cysts, 3 epidermoid cysts, and 3 arachnoid cysts) were evaluated with conventional MRI, DWI, and in vivo (1)H MRS. Preoperative diagnosis of the lesions was based on the results of DWI and in vivo MRS. All DWI and (1)H MRS studies were performed with a clinical 1.5-T system. The DWI was performed using single-shot spin-echo echo-planar pulse sequence with b = 1000 s/mm(2). The ADC value was measured. Diagnostic accuracy of conventional MRI, DWI, and in vivo (1)H MRS was calculated with respect to a final diagnosis of brain abscess vs nonabscess cystic tumor. RESULTS Lactate and cytosolic amino acids with/without succinate, acetate, and alanine were observed in 18 of 21 cases of abscesses on MRS. In 3 cases of epidermoid cysts, lactate was observed and could be differentiated from 3 cases of arachnoid cysts, which showed only minimal lactate. Only lactate was seen in 14 of 23 patients with tumor cysts, whereas both lipid/lactate and choline were visible in 9 patients with tumor cysts. Increased signal was seen in 20 of 21 patients with abscesses and 3 patients with epidermoid cysts on DWI. Decreased signal was observed in 22 of 23 patients with tumor cysts and 3 patients with arachnoid cyst on DWI. Diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of conventional MRI for the differentiation of brain abscess from nonabscess cystic tumor were 61.4%, 61.9%, 60.9%, 59.1%, and 63.6%, respectively, whereas they were 93.2%, 85.7%, 100%, 100%, and 88.5% with MRS; 95.5%, 95.2%, 95.7%, 95.2%, and 95.7% with DWI; and 97.7%, 95.2%, 100%, 100%, and 95.8% with MRS and DWI. Magnetic resonance imaging, when combined with in vivo MRS and DWI, accurately predicted the diagnosis in 47 (94%) of 50 and 48 (96%) of 50 of the cases, respectively. CONCLUSIONS Proton MRS and DWI are useful as additional diagnostic modalities in differentiating intracranial cystic lesions. Combination of DWI with calculated ADC values and metabolite spectrum acquired by MRS add more information to MRI in the differentiation of intracranial cystic mass lesions.
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Hammoud DA, Pomper MG. Central Nervous System Imaging. Oncology 2007. [DOI: 10.1007/0-387-31056-8_27] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Galanaud D, Nicoli F, Confort-Gouny S, Le Fur Y, Dormont D, Girard N, Ranjeva J, Cozzone P. [Brain magnetic resonance spectroscopy]. ACTA ACUST UNITED AC 2007; 88:483-96. [PMID: 17457259 DOI: 10.1016/s0221-0363(07)89848-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
MR spectroscopy (MRS) sequences allow noninvasive exploration of brain metabolism during a MRI examination. Their day-to-day use in a clinical setting has recently been improved by simple programming of sequences and automated quantification of metabolites. However, a few simple rules should be observed in the choice of sequences and the location of the voxels so as to obtain an informative, high-quality examination. The research applications of MR spectroscopy, where use of this examination seeks to better understand the pathophysiology of the disease, must be distinguished from its clinical indications, where MRS provides information that can be used directly in patient management. The most significant of the clinical uses are imaging intracranial tumors (positive and differential diagnosis, extension, treatment follow-up), diffuse brain injury, encephalopathies (especially hepatic and HIV-related), and the diagnosis of metabolic disorders.
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Affiliation(s)
- D Galanaud
- Service de Neuroradiologie, Hôpital La Pitié Salpêtrière, 47, boulevard de l'Hôpital, 75651 Paris cedex 13.
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Galanaud D, Nicoli F, Confort-Gouny S, Le Fur Y, Ranjeva JP, Viola A, Girard N, Cozzone PJ. [Indications for cerebral MR proton spectroscopy in 2007]. Rev Neurol (Paris) 2007; 163:287-303. [PMID: 17404517 DOI: 10.1016/s0035-3787(07)90402-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Magnetic resonance spectroscopy (MRS) is being increasingly performed alongside the more conventional MRI sequences in the exploration of neurological disorders. It is however important to clearly differentiate its clinical applications aiming at improving the differential diagnosis or the prognostic evaluation of the patient, from the research protocols, when MRS can contribute to a better understanding of the pathophysiology of the disease or to the evaluation of new treatments. The most important applications in clinical practice are intracranial space occupying lesions (especially the positive diagnosis of intracranial abscesses and gliomatosis cerebri and the differential diagnosis between edema and tumor infiltration), alcoholic, hepatic, and HIV-related encephalopathies and the exploration of metabolic diseases. Among the research applications, MRS is widely used in multiple sclerosis, ischemia and brain injury, epilepsy and neuro degenerative diseases.
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Affiliation(s)
- D Galanaud
- Centre de Résonance Magnétique Biologique et Médicale (CRMBM), UMR CNRS 6612, Faculté de Médecine et Hôpital La Timone, Marseille, France
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Grand S, Kremer S, Tropres I, Pasteris C, Krainik A, Hoffmann D, Chabardes S, Berger F, Pasquier B, Lefournier V, Le Bas JF. Spectroscopie 1H, perfusion, diffusion : quelle place pour ces techniques lors du diagnostic et du suivi des principales tumeurs cérébrales sus-tentorielles de l’adulte ? Rev Neurol (Paris) 2006; 162:1204-20. [PMID: 17151513 DOI: 10.1016/s0035-3787(06)75134-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
INTRODUCTION In a few years, magnetic resonance imaging (MRI) has evolved from a morphology-based examination to one that encompasses metabolism and function. STATE OF ART MRI is a well-established tool for the initial evaluation of brain tumors, but conventional MR sequences have some limitations. Conventional MRI is unable to distinguish high-grade glioma from metastasis and abscess, to define precisely the histopathological grade of gliomas, to determine exactly the limits of tumor extension, to characterize meningeal tumors. Differentiation of tumor recurrence from treatment-related changes may be difficult with standard MR imaging because the interpretation is essentially based on volume analysis. PERSPECTIVES 1H Spectroscopy, diffusion and perfusion imaging become possible with the development of MR imagers and can be routinely performed in clinical settings. They give complementary information about tumor metabolism and vascularity and allow a better analysis of post-treatment modifications. Functional and metabolic explorations should be used to characterize brain tumors.
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Hoerr V, Hoffmann K, Schollmayer C, Holzgrabe U, Haase A, Jakob P, Faber C. Assessment of inhibitory potency of antibiotics by MRI: apparent T2 as a marker of cell growth. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2006; 19:247-55. [PMID: 17096123 DOI: 10.1007/s10334-006-0053-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2006] [Revised: 09/20/2006] [Accepted: 10/06/2006] [Indexed: 10/23/2022]
Abstract
A new method to assess the antibiotic potency by MRI has been developed. Correlating 1H NMR spectra of bacterial cultures with the extracellular parameters T2, OD600, and pH, a relationship between cell growth and T2 variations was established. T2 is influenced by chemical exchange that depends on pH, composition, and concentration of the medium. Changes in the medium from bacterial metabolism are reflected in alternating T2 values. At 17.6 T, growth curves based on T2 values were measured simultaneously of several cultures of Streptococcus vestibularis. From T2 growth curves in the presence of varying concentrations of vancomycin, the minimum inhibitory concentration of the antibiotic could be determined to be 0.33+/-0.08 microM. This value was in good agreement with the result obtained by the conventional broth microdilution. In principle, T2 growth curves can be determined on a large number of cultures simultaneously and may potentially be used as a novel tool in high through-put screening of novel anti-infective substances.
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Affiliation(s)
- Verena Hoerr
- Institute of Pharmacy and Food Chemistry, University of Würzburg, Würzburg, Germany
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Al-Okaili RN, Krejza J, Wang S, Woo JH, Melhem ER. Advanced MR Imaging Techniques in the Diagnosis of Intraaxial Brain Tumors in Adults. Radiographics 2006; 26 Suppl 1:S173-89. [PMID: 17050514 DOI: 10.1148/rg.26si065513] [Citation(s) in RCA: 137] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Intraaxial brain masses are a significant health problem and present several imaging challenges. The role of imaging is no longer limited to merely providing anatomic details. Sophisticated magnetic resonance (MR) imaging techniques allow insight into such processes as the freedom of water molecule movement, the microvascular integrity and hemodynamic characteristics, and the chemical makeup of certain compounds of masses. The role of the most commonly used advanced MR imaging techniques-perfusion imaging, diffusion-weighted imaging, and MR spectroscopy-in the diagnosis and classification of the most common intraaxial brain tumors in adults is explored. These lesions include primary neoplasms (high- and low-grade), secondary (meta-static) neoplasms, lymphoma, tumefactive demyelinating lesions, abscesses, and encephalitis. Application of a diagnostic algorithm that integrates advanced MR imaging features with conventional MR imaging findings may help the practicing radiologist make a more specific diagnosis for an intraaxial tumor.
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Affiliation(s)
- Riyadh N Al-Okaili
- Department of Radiology, University of Pennsylvania School of Medicine, 3400 Spruce St, Dulles 2, Philadelphia, PA 19104, USA
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Rennert J, Stadlbauer A, Nimsky C, Doerfler A, Ganslandt O. Usefulness of 1H-MRS in the diagnosis of contrast enhancing cystic lesions: A case report. ACTA ACUST UNITED AC 2006; 56:99-104. [PMID: 17051964 DOI: 10.1016/j.rontge.2006.05.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The clinical and radiological features of brain abscesses can sometimes imitate those of necrotic tumors or metastasis. Whereas the approach and urgency of surgical intervention differs enormously, further diagnostic features are necessary in order to establish the correct preoperative diagnosis. We report on two patients who presented with septated ring-enhancing lesions in the right parieto-temporat hemisphere with perifocal edema and discuss the role of 1H-magnetic resonance spectroscopy (MRS) in the diagnosis of contrast enhancing cystic lesions.
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Affiliation(s)
- Janine Rennert
- Department of Neuroradiology, University of Erlangen-Nuremberg, Schwabachanlage 6, 91054 Erlangen, Germany.
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Sorrell TC, Wright LC, Malik R, Himmelreich U. Application of proton nuclear magnetic resonance spectroscopy to the study of Cryptococcus and cryptococcosis. FEMS Yeast Res 2006; 6:558-66. [PMID: 16696651 DOI: 10.1111/j.1567-1364.2006.00079.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Proton nuclear magnetic resonance spectroscopy is a nondestructive technique that identifies chemicals in solution and in living cells. It has been used in cryptococcal research to identify the primary structure of capsular glucuronoxylomannans, link cellular apoptosis susceptibility (CAS) genes to positioning of residues on the mannose backbone of glucuronoxylomannan, and verify that the cryptococcal virulence determinant, phospholipase B, is elaborated in vivo. Promising clinical applications include speciation (Cryptococcus neoformans and Cryptococcus gattii), with preliminary evidence that varieties neoformans and grubii can also be distinguished, non-invasive diagnosis of cerebral cryptococcomas, and, in cases of meningitis, monitoring therapeutic response by analysis of cerebrospinal fluid.
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Affiliation(s)
- Tania C Sorrell
- Centre for Infectious Diseases and Microbiology and Westmead Millennium Institute, University of Sydney at Westmead, NSW, Australia.
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Tate AR, Underwood J, Acosta DM, Julià-Sapé M, Majós C, Moreno-Torres A, Howe FA, van der Graaf M, Lefournier V, Murphy MM, Loosemore A, Ladroue C, Wesseling P, Luc Bosson J, Cabañas ME, Simonetti AW, Gajewicz W, Calvar J, Capdevila A, Wilkins PR, Bell BA, Rémy C, Heerschap A, Watson D, Griffiths JR, Arús C. Development of a decision support system for diagnosis and grading of brain tumours using in vivo magnetic resonance single voxel spectra. NMR IN BIOMEDICINE 2006; 19:411-34. [PMID: 16763971 DOI: 10.1002/nbm.1016] [Citation(s) in RCA: 144] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
A computer-based decision support system to assist radiologists in diagnosing and grading brain tumours has been developed by the multi-centre INTERPRET project. Spectra from a database of 1H single-voxel spectra of different types of brain tumours, acquired in vivo from 334 patients at four different centres, are clustered according to their pathology, using automated pattern recognition techniques and the results are presented as a two-dimensional scatterplot using an intuitive graphical user interface (GUI). Formal quality control procedures were performed to standardize the performance of the instruments and check each spectrum, and teams of expert neuroradiologists, neurosurgeons, neurologists and neuropathologists clinically validated each case. The prototype decision support system (DSS) successfully classified 89% of the cases in an independent test set of 91 cases of the most frequent tumour types (meningiomas, low-grade gliomas and high-grade malignant tumours--glioblastomas and metastases). It also helps to resolve diagnostic difficulty in borderline cases. When the prototype was tested by radiologists and other clinicians it was favourably received. Results of the preliminary clinical analysis of the added value of using the DSS for brain tumour diagnosis with MRS showed a small but significant improvement over MRI used alone. In the comparison of individual pathologies, PNETs were significantly better diagnosed with the DSS than with MRI alone.
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Affiliation(s)
- Anne R Tate
- St George's, University of London, Cranmer Terrace, London SW17 0RE, UK
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50
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Galanaud D, Nicoli F, Figarella-Branger D, Roche P, Confort-Gouny S, Le Fur Y, Cozzone PJ. Spectroscopie par résonance magnétique des tumeurs cérébrales. ACTA ACUST UNITED AC 2006; 87:822-32. [PMID: 16778750 DOI: 10.1016/s0221-0363(06)74090-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
MR spectroscopy (MRS) can complement MRI in the evaluation of intracranial tumors. Before treatment, MRS can contribute to the differential diagnosis between tumor and non tumoral lesion (especially intracranial abscesses), to assess the aggressiveness of a glial tumor or to determine its extension to better delineate the surgical removal or the target volume of radiotherapy. During treatment follow-up, MRS helps differentiate recurrent tumor from radionecrosis or physiological post-surgical contrast enhancement. The current studies are trying to determine if the indications of MRS, alone or in association with other MR sequences can further be extended in the study of brain tumors, in particular the follow-up of lesions undergoing chemo or radiotherapy.
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Affiliation(s)
- D Galanaud
- CRMBM CEMEREM UMR CRNS 6612, Faculté de Médecine, 27, boulevard Jean Moulin, 13005 Marseille.
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