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Gholizadeh N, Pundavela J, Nagarajan R, Dona A, Quadrelli S, Biswas T, Greer PB, Ramadan S. Nuclear magnetic resonance spectroscopy of human body fluids and in vivo magnetic resonance spectroscopy: Potential role in the diagnosis and management of prostate cancer. Urol Oncol 2020; 38:150-173. [PMID: 31937423 DOI: 10.1016/j.urolonc.2019.10.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 09/22/2019] [Accepted: 10/31/2019] [Indexed: 01/17/2023]
Abstract
Prostate cancer is the most common solid organ cancer in men, and the second most common cause of male cancer-related mortality. It has few effective therapies, and is difficult to diagnose accurately. Prostate-specific antigen (PSA), which is currently the most effective diagnostic tool available, cannot reliably discriminate between different pathologies, and in fact only around 30% of patients found to have elevated levels of PSA are subsequently confirmed to actually have prostate cancer. As such, there is a desperate need for more reliable diagnostic tools that will allow the early detection of prostate cancer so that the appropriate interventions can be applied. Nuclear magnetic resonance (NMR) spectroscopy and magnetic resonance spectroscopy (MRS) are 2 high throughput, noninvasive analytical procedures that have the potential to enable differentiation of prostate cancer from other pathologies using metabolomics, by focusing specifically on certain metabolites which are associated with the development of prostate cancer cells and its progression. The value that this type of approach has for the early detection, diagnosis, prognosis, and personalized treatment of prostate cancer is becoming increasingly apparent. Recent years have seen many promising developments in the fields of NMR spectroscopy and MRS, with improvements having been made to hardware as well as to techniques associated with the acquisition, processing, and analysis of related data. This review focuses firstly on proton NMR spectroscopy of blood serum, urine, and expressed prostatic secretions in vitro, and then on 1- and 2-dimensional proton MRS of the prostate in vivo. Major advances in these fields and methodological principles of data collection, acquisition, processing, and analysis are described along with some discussion of related challenges, before prospects that proton MRS has for future improvements to the clinical management of prostate cancer are considered.
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Affiliation(s)
- Neda Gholizadeh
- School of Health Sciences, Faculty of Health and Medicine, University of Newcastle, Newcastle, NSW, Australia
| | - Jay Pundavela
- Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Rajakumar Nagarajan
- Human Magnetic Resonance Center, Institute for Applied Life Sciences, University of Massachusetts Amherst, MA, USA
| | - Anthony Dona
- Kolling Institute of Medical Research, Royal North Shore Hospital, University of Sydney, St Leonards, NSW, Australia
| | - Scott Quadrelli
- School of Health Sciences, Faculty of Health and Medicine, University of Newcastle, Newcastle, NSW, Australia; Radiology Department, Princess Alexandra Hospital, Brisbane, QLD, Australia
| | - Tapan Biswas
- Department of Instrumentation and Electronics Engineering, Jadavpur University, Kolkata, India
| | - Peter B Greer
- School of Mathematical and Physical Sciences, University of Newcastle, Newcastle, NSW, Australia; Radiation Oncology, Calvary Mater Newcastle, Newcastle, NSW, Australia
| | - Saadallah Ramadan
- School of Health Sciences, Faculty of Health and Medicine, University of Newcastle, Newcastle, NSW, Australia; Imaging Centre, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia.
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Bogner W, Hangel G, Esmaeili M, Andronesi OC. 1D-spectral editing and 2D multispectral in vivo 1H-MRS and 1H-MRSI - Methods and applications. Anal Biochem 2017; 529:48-64. [PMID: 28034791 DOI: 10.1016/j.ab.2016.12.020] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 12/16/2016] [Accepted: 12/23/2016] [Indexed: 12/27/2022]
Abstract
This article reviews the methodological aspects of detecting low-abundant J-coupled metabolites via 1D spectral editing techniques and 2D nuclear magnetic resonance (NMR) methods applied in vivo, in humans, with a focus on the brain. A brief explanation of the basics of J-evolution will be followed by an introduction to 1D spectral editing techniques (e.g., J-difference editing, multiple quantum coherence filtering) and 2D-NMR methods (e.g., correlation spectroscopy, J-resolved spectroscopy). Established and recently developed methods will be discussed and the most commonly edited J-coupled metabolites (e.g., neurotransmitters, antioxidants, onco-markers, and markers for metabolic processes) will be briefly summarized along with their most important applications in neuroscience and clinical diagnosis.
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Affiliation(s)
- Wolfgang Bogner
- High-Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University Vienna, Vienna, Austria.
| | - Gilbert Hangel
- High-Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University Vienna, Vienna, Austria.
| | - Morteza Esmaeili
- Department of Circulation and Medical Imaging, NTNU, Norwegian University of Science and Technology, Trondheim, Norway; Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA.
| | - Ovidiu C Andronesi
- Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA.
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Aydın H, Kızılgöz V, Tekin BO. Overview of current multiparametric magnetic resonance imaging approach in the diagnosis and staging of prostate cancer. Kaohsiung J Med Sci 2015; 31:167-78. [DOI: 10.1016/j.kjms.2015.01.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 10/07/2014] [Accepted: 02/19/2014] [Indexed: 01/08/2023] Open
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Lemaître G, Martí R, Freixenet J, Vilanova JC, Walker PM, Meriaudeau F. Computer-Aided Detection and diagnosis for prostate cancer based on mono and multi-parametric MRI: a review. Comput Biol Med 2015; 60:8-31. [PMID: 25747341 DOI: 10.1016/j.compbiomed.2015.02.009] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 02/11/2015] [Accepted: 02/12/2015] [Indexed: 12/30/2022]
Abstract
Prostate cancer is the second most diagnosed cancer of men all over the world. In the last few decades, new imaging techniques based on Magnetic Resonance Imaging (MRI) have been developed to improve diagnosis. In practise, diagnosis can be affected by multiple factors such as observer variability and visibility and complexity of the lesions. In this regard, computer-aided detection and computer-aided diagnosis systems have been designed to help radiologists in their clinical practice. Research on computer-aided systems specifically focused for prostate cancer is a young technology and has been part of a dynamic field of research for the last 10 years. This survey aims to provide a comprehensive review of the state-of-the-art in this lapse of time, focusing on the different stages composing the work-flow of a computer-aided system. We also provide a comparison between studies and a discussion about the potential avenues for future research. In addition, this paper presents a new public online dataset which is made available to the research community with the aim of providing a common evaluation framework to overcome some of the current limitations identified in this survey.
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Affiliation(s)
- Guillaume Lemaître
- LE2I-UMR CNRS 6306, Université de Bourgogne, 12 rue de la Fonderie, 71200 Le Creusot, France; ViCOROB, Universitat de Girona, Campus Montilivi, Edifici P4, 17071 Girona, Spain.
| | - Robert Martí
- ViCOROB, Universitat de Girona, Campus Montilivi, Edifici P4, 17071 Girona, Spain.
| | - Jordi Freixenet
- ViCOROB, Universitat de Girona, Campus Montilivi, Edifici P4, 17071 Girona, Spain.
| | - Joan C Vilanova
- Department of Magnetic Resonance, Clínica Girona, Lorenzana 36, 17002 Girona, Spain
| | - Paul M Walker
- LE2I-UMR CNRS 6306, Université de Bourgogne, Avenue Alain Savary, 21000 Dijon, France.
| | - Fabrice Meriaudeau
- LE2I-UMR CNRS 6306, Université de Bourgogne, 12 rue de la Fonderie, 71200 Le Creusot, France.
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Serkova NJ, Niemann CU. Pattern recognition and biomarker validation using quantitative1H-NMR-based metabolomics. Expert Rev Mol Diagn 2014; 6:717-31. [PMID: 17009906 DOI: 10.1586/14737159.6.5.717] [Citation(s) in RCA: 127] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The collection of global metabolic data and their interpretation (both spectral and biochemical) using modern spectroscopic techniques and appropriate statistical approaches, are known as 'metabolic profiling', 'metabonomics' or 'metabolomics'. This review addresses 1H-nuclear magnetic resonance (NMR)-based metabolomic principles and their application in biomedical science, with special emphasis on their potential in translational research in transplantation, oncology, and drug toxicity or discovery. Various steps in metabolomics analysis are described in order to illustrate the types of biological samples, their respective handling and preparation for 1H-NMR analysis; provide a rationale for using pattern-recognition techniques (spectral database concept) versus quantitative 1H-NMR-based metabolomics (metabolite database concept); and identify necessary technological and logistical future developments that will allow 1H-NMR-based metabolomics to become an established tool in biomedical research and patient care.
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Affiliation(s)
- Natalie J Serkova
- University of Colorado Health Sciences Center, Biomedical MRI/MRS Cancer Center Core, Department of Anesthesiology, Denver, CO 80262, USA.
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Thomas MA, Nagarajan R, Huda A, Margolis D, Sarma MK, Sheng K, Reiter RE, Raman SS. Multidimensional MR spectroscopic imaging of prostate cancer in vivo. NMR IN BIOMEDICINE 2014; 27:53-66. [PMID: 23904127 DOI: 10.1002/nbm.2991] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Revised: 04/12/2013] [Accepted: 05/21/2013] [Indexed: 06/02/2023]
Abstract
Prostate cancer (PCa) is the second most common type of cancer among men in the United States. A major limitation in the management of PCa is an inability to distinguish, early on, cancers that will progress and become life threatening. One-dimensional (1D) proton ((1)H) MRS of the prostate provides metabolic information such as levels of choline (Ch), creatine (Cr), citrate (Cit), and spermine (Spm) that can be used to detect and diagnose PCa. Ex vivo high-resolution magic angle spinning (HR-MAS) of PCa specimens has revealed detection of more metabolites such as myo-inositol (mI), glutamate (Glu), and glutamine (Gln). Due to the J-modulation and signal overlap, it is difficult to quantitate Spm and other resonances in the prostate clearly by single- and multivoxel-based 1D MR spectroscopy. This limitation can be minimized by adding at least one more spectral dimension by which resonances can be spread apart, thereby increasing the spectral dispersion. However, recording of multivoxel-based two-dimensional (2D) MRS such as J-resolved spectroscopy (JPRESS) and correlated spectroscopy (L-COSY) combined with 2D or three-dimensional (3D) magnetic resonance spectroscopic imaging (MRSI) using conventional phase-encoding can be prohibitively long to be included in a clinical protocol. To reduce the long acquisition time required for spatial encoding, the echo-planar spectroscopic imaging (EPSI) technique has been combined with correlated spectroscopy to give four-dimensional (4D) echo-planar correlated spectroscopic imaging (EP-COSI) as well as J-resolved spectroscopic imaging (EP-JRESI) and the multi-echo (ME) variants. Further acceleration can be achieved using non-uniform undersampling (NUS) and reconstruction using compressed sensing (CS). Earlier versions of 2D MRS, theory of 2D MRS, spectral apodization filters, newer developments and the potential role of multidimensional MRS in PCa detection and management will be reviewed here.
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Affiliation(s)
- M Albert Thomas
- Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
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Spermine and citrate as metabolic biomarkers for assessing prostate cancer aggressiveness. PLoS One 2013; 8:e62375. [PMID: 23626811 PMCID: PMC3633894 DOI: 10.1371/journal.pone.0062375] [Citation(s) in RCA: 125] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Accepted: 03/20/2013] [Indexed: 11/19/2022] Open
Abstract
Separating indolent from aggressive prostate cancer is an important clinical challenge for identifying patients eligible for active surveillance, thereby reducing the risk of overtreatment. The purpose of this study was to assess prostate cancer aggressiveness by metabolic profiling of prostatectomy tissue and to identify specific metabolites as biomarkers for aggressiveness. Prostate tissue samples (n = 158, 48 patients) with a high cancer content (mean: 61.8%) were obtained using a new harvesting method, and metabolic profiles of samples representing different Gleason scores (GS) were acquired by high resolution magic angle spinning magnetic resonance spectroscopy (HR-MAS). Multivariate analysis (PLS, PLS-DA) and absolute quantification (LCModel) were used to examine the ability to predict cancer aggressiveness by comparing low grade (GS = 6, n = 30) and high grade (GS≥7, n = 81) cancer with normal adjacent tissue (n = 47). High grade cancer tissue was distinguished from low grade cancer tissue by decreased concentrations of spermine (p = 0.0044) and citrate (p = 7.73·10−4), and an increase in the clinically applied (total choline+creatine+polyamines)/citrate (CCP/C) ratio (p = 2.17·10−4). The metabolic profiles were significantly correlated to the GS obtained from each tissue sample (r = 0.71), and cancer tissue could be distinguished from normal tissue with sensitivity 86.9% and specificity 85.2%. Overall, our findings show that metabolic profiling can separate aggressive from indolent prostate cancer. This holds promise for the benefit of applying in vivo magnetic resonance spectroscopy (MRS) within clinical MR imaging investigations, and HR-MAS analysis of transrectal ultrasound-guided biopsies has a potential as an additional diagnostic tool.
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Li B, Du Y, Yang H, Huang Y, Meng J, Xiao D. Magnetic resonance imaging for prostate cancer clinical application. Chin J Cancer Res 2013; 25:240-9. [PMID: 23592906 DOI: 10.3978/j.issn.1000-9604.2013.03.06] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2012] [Accepted: 12/14/2012] [Indexed: 01/16/2023] Open
Abstract
As prostate cancer is a biologically heterogeneous disease for which a variety of treatment options are available, the major objective of prostate cancer imaging is to achieve more precise disease characterization. In clinical practice, magnetic resonance imaging (MRI) is one of the imaging tools for the evaluation of prostate cancer, the fusion of MRI or dynamic contrast-enhanced MRI (DCE-MRI) with magnetic resonance spectroscopic imaging (MRSI) is improving the evaluation of cancer location, size, and extent, while providing an indication of tumor aggressiveness. This review summarizes the role of MRI in the application of prostate cancer and describes molecular MRI techniques (including MRSI and DCE-MRI) for aiding prostate cancer management.
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Affiliation(s)
- Bing Li
- Sichuan Key Laboratory of Medical Imaging, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000, China ; Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000, China
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Kauppinen RA, Peet AC. Using magnetic resonance imaging and spectroscopy in cancer diagnostics and monitoring: preclinical and clinical approaches. Cancer Biol Ther 2012; 12:665-79. [PMID: 22004946 DOI: 10.4161/cbt.12.8.18137] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Nuclear Magnetic Resonance (MR) based imaging has become an integrated domain in today's oncology research and clinical management of cancer patients. MR is a unique imaging modality among numerous other imaging modalities by providing access to anatomical, physiological, biochemical and molecular details of tumour with excellent spatial and temporal resolutions. In this review we will cover established and investigational MR imaging (MRI) and MR spectroscopy (MRS) techniques used for cancer imaging and demonstrate wealth of information on tumour biology and clinical applications MR techniques offer for oncology research both in preclinical and clinical settings. Emphasis is given not only to the variety of information which may be obtained but also the complementary nature of the techniques. This ability to determine tumour type, grade, invasiveness, degree of hypoxia, microvacular characteristics, and metabolite phenotype, has already profoundly transformed oncology research and patient management. It is evident from the data reviewed that MR techniques will play a key role in uncovering molecular fingerprints of cancer, developing targeted treatment strategies and assessing responsiveness to treatment for personalized patient management, thereby allowing rapid translation of imaging research conclusions into the benefit of clinical oncology.
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Nagarajan R, Gomez AM, Raman SS, Margolis DJ, McClure T, Thomas MA. Correlation of endorectal 2D JPRESS findings with pathological Gleason scores in prostate cancer patients. NMR IN BIOMEDICINE 2010; 23:257-261. [PMID: 19795373 DOI: 10.1002/nbm.1446] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
To determine the metabolite ratios of (Cho + Cr)/Cit and (Cho + Cr)/Spm in patients with two ranges of pathological Gleason scores, namely (3 + 4) and (4 + 3). By using the localized two-dimensional (2D) J-resolved spectroscopy (JPRESS) technique, the metabolites ratios can be calculated and correlated with prostate cancer aggressiveness. A total of 24 patients who underwent endorectal 2D JPRESS between April 2006 and July 2007 were included in this study. The 2D JPRESS voxel was localized predominantly in the peripheral zone suspected for malignancy based on pathology. Using the metabolites such as total choline (Cho), creatine (Cr), spermine (Spm) and citrate (Cit), the ratios (Cho + Cr)/Cit and (Cho + Cr)/Spm were calculated. In 14 prostate cancer patients who had a final pathologic Gleason scores of i) (3 + 4 = 7, n = 7) and ii) (4 + 3 = 7, n = 7), the metabolite ratios (mean +/- SD) of (Cho + Cr)/Cit and (Cho + Cr)/Spm were calculated using the 2D JPRESS spectra as follows: i) (1.48 +/- 0.83) and (1.59 +/- 0.73); ii) (2.90 +/- 0.94) and (2.71 +/- 1.47), respectively. Higher percentage of aggressive disease correlates with higher metabolites ratio. Our pilot study suggests that 2D JPRESS can be reliably evaluated in a clinical setting using an endorectal coil. In addition to the citrate ratio, the spermine ratio also correlates with pathology based Gleason score.
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Affiliation(s)
- Rajakumar Nagarajan
- Department of Radiology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
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Huang Y, Cai S, Lin Y, Chen Z. An intermolecular single-quantum coherence detection scheme for high-resolution two-dimensional J-resolved spectroscopy in inhomogeneous fields. APPLIED SPECTROSCOPY 2010; 64:235-240. [PMID: 20149286 DOI: 10.1366/000370210790619645] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A new pulse sequence based on intermolecular single-quantum coherences (iSQCs) is proposed to achieve high-resolution two-dimensional (2D) J-resolved spectra in inhomogeneous fields via three-dimensional (3D) acquisition. Since the iSQC evolution period and spin echo evolution period in this sequence are intrinsically insensitive to magnetic field inhomogeneities, high-resolution 2D J-resolved spectra can be recovered from nuclei in inhomogeneous fields by projecting the 3D data onto the 2D plane. Analytical expressions of the resulting signals were derived assuming the secular dipole-dipole interaction. Analyses of a solution sample placed in a deliberately unshimmed magnetic field and of a biological sample with intrinsic field inhomogeneities were performed. The results show that this sequence provides an attractive and efficient way to eliminate the influence of field inhomogeneities on 2D J-resolved spectra, which is potentially useful for characterizing complex chemical materials and studying biological metabolites in inhomogeneous fields.
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Affiliation(s)
- Yuqing Huang
- Department of Physics, Fujian Key Laboratory of Plasma and Magnetic Resonance, Xiamen University, Xiamen 361005, PR China
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Abstract
Commercial MR imaging/magnetic resonance spectroscopic imaging (MRSI) packages for staging prostate cancer on 1.5-T MR scanners are now available. The technology is becoming mature enough to begin assessing its clinical utility in selecting, planning, and following prostate cancer therapy. Before therapy, 1.5-T MR imaging/MRSI has the potential to improve the local evaluation of prostate cancer presence and volume and has a significant incremental benefit in the prediction of pathologic stage when added to clinical nomograms. After therapy, two metabolic biomarkers of effective and ineffective therapy have been identified and are being validated with 10-year outcomes. Accuracy can be improved by performing MR imaging/MRSI at higher magnetic field strengths, using more sensitive hyperpolarized (13)C MRSI techniques and through the addition of other functional MR techniques.
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Affiliation(s)
- John Kurhanewicz
- University of California, San Francisco, San Francisco, CA 94158, USA.
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Lange T, Schulte RF, Boesiger P. Quantitative J-resolved prostate spectroscopy using two-dimensional prior-knowledge fitting. Magn Reson Med 2008; 59:966-72. [PMID: 18429013 DOI: 10.1002/mrm.21438] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Two-dimensional (2D) prior-knowledge fitting (ProFit) was adapted and applied for the quantification of J-resolved (JPRESS) spectra acquired at a field strength of 3T from the human prostate in vivo. In contrast to methods based on simple line fitting and peak integration, commonly applied for metabolite quantification in the prostate, ProFit yields metabolite concentration ratios that are independent of sequence and field strength, since it is based on the linear combination of 2D basis spectra. It is demonstrated that ProFit benefits from the increased information content and reduced baseline distortion in JPRESS prostate spectra, in particular for the quantification of coupled metabolites like citrate (Cit), spermine (Spm), and myo-inositol (mI). The method is validated with 10 repetitive prostate measurements on the same subject. Furthermore, a study carried out on 10 healthy subjects shows that the six prostate metabolites creatine (Cr), total choline (Cho), Cit, Spm, mI, and scyllo-inositol (sI) can be reliably detected in vivo, some of which--especially total Cho and Cit--have proven to be useful markers for the detection of prostate cancer.
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Affiliation(s)
- Thomas Lange
- Institute for Biomedical Engineering, University and ETH Zurich, Gloriastrasse 35, Zurich, Switzerland
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Thomas MA, Lange T, Velan SS, Nagarajan R, Raman S, Gomez A, Margolis D, Swart S, Raylman RR, Schulte RF, Boesiger P. Two-dimensional MR spectroscopy of healthy and cancerous prostates in vivo. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2008; 21:443-58. [PMID: 18633659 DOI: 10.1007/s10334-008-0121-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2007] [Revised: 06/13/2008] [Accepted: 06/19/2008] [Indexed: 12/23/2022]
Abstract
OBJECTIVES A major goal of this article is to summarize the current status of evaluating prostate metabolites non-invasively using spatially resolved two-dimensional (2D) MR Spectroscopy (MRS). MATERIALS AND METHODS Due to various technical challenges, the spatially resolved versions of 2D MRS techniques are currently going through the developmental stage. During the last decade, four different versions of 2D MRS sequences have been successfully implemented on 3T and 1.5T MRI scanners manufactured by three different vendors. These sequences include half and maximum echo sampled J-resolved spectroscopy (JPRESS), S-PRESS and L-COSY, which are single volume localizing sequences, and the multi-voxel based JPRESS sequence. RESULTS Even though greater than 1ml voxels have been used, preliminary evaluations of 2D JPRESS, S-PRESS and L-COSY sequences have demonstrated unambiguous detection of citrate, creatine, choline, spermine and more metabolites in human prostates. ProFIT-based quantitation of JPRESS and L-COSY data clearly shows the superiority of 2D MRS over conventional one-dimensional (1D) MRS and more than six metabolites have been successfully quantified. These sequences have been evaluated in a small group of prostate pathologies and pilot investigations using these sequences show promising results in prostate pathologies. CONCLUSION Implementation of the state-of-the-art 2D MRS techniques and preliminary evaluation in prostate pathologies are discussed in this review. Even though these techniques are going through developmental and early testing phases, it is evident that 2D MRS can be easily added on to any clinical Magnetic Resonance Imaging (MRI) protocol to non-invasively record the biochemical contents of the prostate.
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Affiliation(s)
- M Albert Thomas
- Department of Radiological Sciences, David Geffen School of Medicine at UCLA, 10833 Le Conte Avenue, Los Angeles, CA 90095-1721, USA.
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Weis J, Ahlström H, Hlavcak P, Häggman M, Ortiz-Nieto F, Bergman A. Two-dimensional spectroscopic imaging for pretreatment evaluation of prostate cancer: comparison with the step-section histology after radical prostatectomy. Magn Reson Imaging 2008; 27:87-93. [PMID: 18599244 DOI: 10.1016/j.mri.2008.05.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2007] [Revised: 04/17/2008] [Accepted: 05/20/2008] [Indexed: 11/29/2022]
Abstract
PURPOSE To minimize user and vendor dependence of the spectrum processing of prostate spectra, to measure the ratio of choline (Cho) plus creatine (Cr) to citrate (Cit) in the prostate tissue of normal volunteers and cancer patients, and to compare the results with pathologic findings after radical prostatectomy. MATERIALS AND METHODS Four healthy volunteers and 13 patients with prostate cancer were measured. Measurements were performed using two-dimensional magnetic resonance spectroscopic imaging (MRSI) and endorectal coil. A standard vendor's spectrum processing approach has been modified. An original feature of this methodology was the combination of vendor-optimized and user-independent spectrum preprocessing in the scanner and user-independent quantitation in the environment of an MRUI software package. (Cho+Cr)/Cit ratio was used for the classification of prostate tissue. Results were compared with histopathology after radical prostatectomy. RESULTS Eight of 13 cancer patients were classified as suspicious or very suspicious for cancer at spectroscopy, three were ambiguous for cancer and two patients were evaluated as false negative. A considerable overlap of metabolite ratios at various Gleason score was found. CONCLUSION The proposed spectrum processing has the potential to improve the accuracy and user independency of the (Cho+Cr)/Cit quantitation. This study confirmed the previous results that a considerable overlap of (Cho+Cr)/Cit ratios exists at various Gleason score levels.
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Affiliation(s)
- Jan Weis
- Department of Radiology, Uppsala University Hospital, SE-751 85 Uppsala, Sweden.
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Abstract
MRI spectroscopy is a non invasive method for detecting active metabolites used as markers. Chorine and citrate are used for analyzing prostate cancer. MRI spectroscopy combines morphologic imaging and metabolic cartography. This combination allows a new approach for the diagnosis of prostate cancer in patients with negative biopsy and high Levels of PSA. With MRI spectroscopy the Local staging of prostate cancer has a better accuracy than with MRI alone. It can also be used for the diagnosis of residual disease and recurrence in patients treated with conservative therapy.
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Margolis DJA, Hoffman JM, Herfkens RJ, Jeffrey RB, Quon A, Gambhir SS. Molecular Imaging Techniques in Body Imaging. Radiology 2007; 245:333-56. [DOI: 10.1148/radiol.2452061117] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Shukla-Dave A, Hricak H, Moskowitz C, Ishill N, Akin O, Kuroiwa K, Spector J, Kumar M, Reuter VE, Koutcher JA, Zakian KL. Detection of prostate cancer with MR spectroscopic imaging: an expanded paradigm incorporating polyamines. Radiology 2007; 245:499-506. [PMID: 17890357 DOI: 10.1148/radiol.2452062201] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To characterize benign and malignant prostate peripheral zone (PZ) tissue retrospectively by using a commercial magnetic resonance (MR) spectroscopic imaging package and incorporating the choline plus creatine-to-citrate ratio ([Cho + Cr]/Cit) and polyamine (PA) information into a statistically based voxel classification procedure. MATERIALS AND METHODS The institutional review board approved this HIPAA-compliant study and waived the requirement for informed consent. Fifty men (median age, 60 years; range, 44-69 years) with untreated biopsy-proved prostate cancer underwent combined endorectal MR imaging and MR spectroscopic imaging. Commercial software was used to acquire and process MR spectroscopic imaging data. The (Cho + Cr)/Cit and the PA level were tabulated for each voxel. The PA level was scored on a scale of 0 (PA undetectable) to 2 (PA peak as high as or higher than Cho peak). Whole-mount step-section histopathologic analysis constituted the reference standard. Classification and regression tree analysis in a training set generated a decision-making tree (rule) for classifying voxels as malignant or benign, which was validated in a test set. Receiver operating characteristic and generalized estimating equation regression analyses were used to assess accuracy and sensitivity, respectively. RESULTS The median (Cho + Cr)/Cit was 0.55 (mean +/- standard deviation, 0.59 +/- 0.03) in benign and 0.77 (mean, 1.08 +/- 0.20) in malignant PZ voxels (P = .027). A significantly higher percentage of benign (compared with malignant) voxels had higher PA than choline peaks (P < .001). In the 24-patient training set (584 voxels), the rule yielded 54% sensitivity and 91% specificity for cancer detection; in the 26-patient test set (667 voxels), it yielded 42% sensitivity and 85% specificity. The percentage of cancer in the voxel at histopathologic analysis correlated positively (P < .001) with the sensitivity of the classification and regression tree rule, which was 75% in voxels with more than 90% malignancy. CONCLUSION The statistically based classification rule developed indicated that PAs have an important role in the detection of PZ prostate cancer. With commercial software, this method can be applied in clinical settings.
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Affiliation(s)
- Amita Shukla-Dave
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY 10021 USA.
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21
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Rajesh A, Coakley FV, Kurhanewicz J. 3D MR spectroscopic imaging in the evaluation of prostate cancer. Clin Radiol 2007; 62:921-9. [PMID: 17765456 DOI: 10.1016/j.crad.2007.04.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2006] [Revised: 04/03/2007] [Accepted: 04/11/2007] [Indexed: 11/30/2022]
Abstract
The management of prostate cancer is a complex issue with a varying range of treatment options available. Magnetic resonance (MR) imaging of the prostate has been available for sometime but has the limitation of only anatomical evaluation. Three-dimensional MR spectroscopy is emerging as a new and sensitive tool in the metabolic evaluation of prostate cancer. This article reviews the principle, techniques, and methods of evaluation of spectroscopy and also discusses the applications of spectroscopy in the current management of prostate cancer.
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Affiliation(s)
- A Rajesh
- University Hospitals of Leicester NHS Trust, Leicester General Hospital, Leicester, UK.
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22
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Kim DH, Henry R, Spielman DM. Fast multivoxel two-dimensional spectroscopic imaging at 3 T. Magn Reson Imaging 2007; 25:1155-61. [PMID: 17418519 PMCID: PMC2128753 DOI: 10.1016/j.mri.2007.01.118] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2006] [Revised: 01/24/2007] [Accepted: 01/28/2007] [Indexed: 10/23/2022]
Abstract
The utility of multivoxel two-dimensional chemical shift imaging in the clinical environment will ultimately be determined by the imaging time and the metabolite peaks that can be detected. Different k-space sampling schemes can be characterized by their minimum required imaging time. The use of spiral-based readout gradients effectively reduces the minimum scan time required due to simultaneous data acquisition in three k-space dimensions (k(x), k(y) and k(f(2))). A 3-T spiral-based multivoxel two-dimensional spectroscopic imaging sequence using the PRESS excitation scheme was implemented. Good performance was demonstrated by acquiring preliminary in vivo data for applications, including brain glutamate imaging, metabolite T(2) quantification and high-spatial-resolution prostate spectroscopic imaging. All protocols were designed to acquire data within a 17-min scan time at a field strength of 3 T.
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Affiliation(s)
- Dong-Hyun Kim
- Department of Radiology, University of California-San Francisco, San Francisco, CA, USA.
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23
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Lange T, Trabesinger AH, Schulte RF, Dydak U, Boesiger P. Prostate spectroscopy at 3 Tesla using two-dimensional S-PRESS. Magn Reson Med 2007; 56:1220-8. [PMID: 17094089 DOI: 10.1002/mrm.21082] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Two-dimensional (2D) strong-coupling point-resolved spectroscopy (S-PRESS) is introduced as a novel approach to (1)H MR spectroscopy (MRS) in the prostate. The technique provides full spectral information and allows for an accurate characterization of the citrate (Cit) signal. The method is based on acquiring a series of PRESS spectra with constant total echo time (TE). The indirect dimension is encoded by varying the relative lengths of the first and second TEs (TE(1) + TE(2) = TE). In the resulting 2D spectra, only the signal of strongly coupled spin systems is spread into the second dimension, which leads to more clearly arranged spectra. Furthermore, the spectral parameters of Cit (coupling constant J and chemical shift difference delta of the AB spin system) can be determined with high accuracy in vivo. The sequence is analytically optimized for maximal "strong coupling peaks" of Cit at 3T. 2D S-PRESS spectra are compared with JPRESS spectra in vitro as well as in vivo.
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Affiliation(s)
- Thomas Lange
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
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24
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Kwock L, Smith JK, Castillo M, Ewend MG, Collichio F, Morris DE, Bouldin TW, Cush S. Clinical role of proton magnetic resonance spectroscopy in oncology: brain, breast, and prostate cancer. Lancet Oncol 2006; 7:859-68. [PMID: 17012048 DOI: 10.1016/s1470-2045(06)70905-6] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Standardised proton magnetic resonance spectroscopic imaging (MRSI) was initially developed for routine in-situ clinical assessment of human brain tumours, and its use was later extended for examination of prostate and breast cancers. MRSI coupled with both routine and functional MRI techniques provides more detailed information about a tumour's location and extent of its infiltration than any other modality alone. Information obtained by adding MRSI data to anatomical and functional MRI findings aid in clinical management decisions (such as watchful waiting vs immediate intervention). In this Review, we discuss the current status of proton MRSI, with emphasis on its clinical use to map the location and extent of tumour processes for spectroscopic image-guided biopsy procedures and to monitor treatment paradigms for brain, prostate, and breast cancer.
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Affiliation(s)
- Lester Kwock
- Department of Radiology, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA.
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25
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Shapira B, Frydman L. Spatially encoded pulse sequences for the acquisition of high resolution NMR spectra in inhomogeneous fields. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2006; 182:12-21. [PMID: 16807020 DOI: 10.1016/j.jmr.2006.04.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2006] [Revised: 04/17/2006] [Accepted: 04/19/2006] [Indexed: 05/10/2023]
Abstract
We have recently proposed a protocol for retrieving nuclear magnetic resonance (NMR) spectra based on a spatially-dependent encoding of the MR interactions. It has also been shown that the spatial selectivity with which spins are manipulated during such encoding opens up new avenues towards the removal of magnetic field inhomogeneities; not by demanding extreme Bo field uniformities, but rather by compensating for the dephasing effects introduced by the field distribution at a radiofrequency excitation and/or refocusing level. The present study discusses in further detail a number of strategies deriving from this principle, geared at acquiring both uni- as well as multi-dimensional spectroscopic data at high resolution conditions. Different variants are presented, tailored according to the relative sensitivity and chemical nature of the spin system being explored. In particular a simple multi-scan experiment is discussed capable of affording substantial improvements in the spectral resolution, at nearly no sensitivity or scaling penalties. This new compensation scheme is therefore well-suited for the collection of high-resolution data in low-field systems possessing limited signal-to-noise ratios, where magnetic field heterogeneities might present a serious obstacle. Potential areas of applications of these techniques include high-field in vivo NMR studies in regions near tissue/air interfaces, clinical low field MR spectroscopy on relatively large off-center volumes difficult to shim, and ex situ NMR. The principles of the different compensation methods are reviewed and experimentally demonstrated for one-dimensional inhomogeneities; further improvements and extensions are briefly discussed.
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Affiliation(s)
- Boaz Shapira
- Department of Chemical Physics, Weizmann Institute of Science, 76100 Rehovot, Israel
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26
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Schulte RF, Lange T, Beck J, Meier D, Boesiger P. Improved two-dimensional J-resolved spectroscopy. NMR IN BIOMEDICINE 2006; 19:264-70. [PMID: 16541465 DOI: 10.1002/nbm.1027] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Localised two-dimensional J-resolved spectroscopy (JPRESS) is optimised for the in vivo detection of J-coupled metabolites using magnetic resonance spectroscopy at 3 T. The acquisition of echo signals starts as early as possible (i.e. maximum-echo sampling). This sampling scheme increases sensitivity and decreases overlap of peak tails, hence alleviating baseline problems. Reconstruction issues are discussed and the sensitivity is compared analytically with that of 1D PRESS. The qualitative behaviour of eddy currents in JPRESS is outlined and a 2D eddy current correction procedure based on the 1D phase deconvolution method is proposed.
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Affiliation(s)
- Rolf F Schulte
- Institute for Biomedical Engineering, University and ETH Zurich, CH-8092 Zurich, Switzerland
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27
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Gambarota G, van der Graaf M, Klomp D, Mulkern RV, Heerschap A. Echo-time independent signal modulations using PRESS sequences: a new approach to spectral editing of strongly coupled AB spin systems. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2005; 177:299-306. [PMID: 16169267 DOI: 10.1016/j.jmr.2005.08.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2004] [Revised: 08/05/2005] [Accepted: 08/05/2005] [Indexed: 05/04/2023]
Abstract
In clinical MR spectroscopy, double spin-echo point resolved spectroscopy (PRESS) sequences are routinely used for volume selection. For strongly coupled AB spin systems under PRESS excitation, the dependence of the signal on the echo time TE has been thoroughly investigated, whereas less attention has been paid to the signal modulation which occurs at constant TE with varying interpulse delays. A substantial TE-independent J modulation is here predicted from analytical solutions of the Liouville equation and density matrix simulations, and verified with experiments on citrate at 1.5 and 3T. It is also shown that this modulation effect could be exploited for editing of strongly coupled AB resonances or for removal of singlets in spectra-by means of difference spectroscopy-just using a standard PRESS sequence. The applicability in vivo of this new spectral editing approach is also demonstrated, with selective detection of citrate resonances in the human prostate. This novel approach has the advantages of being simple, and directly applicable on standard clinical MR scanners, provided that the exact behavior of the resonance is known.
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Affiliation(s)
- G Gambarota
- Department of Radiology, Radboud University Nijmegen Medical Center, The Netherlands.
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28
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Abstract
Magnetic resonance spectroscopy (MRS) has been used for more than two decades to interrogate metabolite distributions in living cells and tissues. Techniques have been developed that allow multiple spectra to be obtained simultaneously with individual volume elements as small as 1 uL of tissue (i.e., 1 x 1 x 1 mm(3)). The most common modern applications of in vivo MRS use endogenous signals from (1)H, (31)P, or (23)Na. Important contributions have also been made using exogenous compounds containing (19)F, (13)C, or (17)O. MRS has been used to investigate cardiac and skeletal muscle energetics, neurobiology, and cancer. This review focuses on the latter applications, with specific reference to the measurement of tissue choline, which has proven to be a tumor biomarker that is significantly affected by anticancer therapies.
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Affiliation(s)
- Robert J Gillies
- Arizona Cancer Center, 1515 Campbell Avenue, Tucson, AZ 85724-5024, USA.
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29
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Tal A, Shapira B, Frydman L. A continuous phase-modulated approach to spatial encoding in ultrafast 2D NMR spectroscopy. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2005; 176:107-14. [PMID: 15949960 DOI: 10.1016/j.jmr.2005.05.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2005] [Revised: 05/02/2005] [Accepted: 05/09/2005] [Indexed: 05/02/2023]
Abstract
Ultrafast 2D NMR replaces the time-domain parametrization usually employed to monitor the indirect-domain spin evolution, with an equivalent encoding along a spatial geometry. When coupled to a gradient-assisted decoding during the acquisition, this enables the collection of complete 2D spectra within a single transient. We have presented elsewhere two strategies for carrying out the spatial encoding underlying ultrafast NMR: a discrete excitation protocol capable of imparting a phase-modulated encoding of the interactions, and a continuous protocol yielding amplitude-modulated signals. The former is general but has associated with it a number of practical complications; the latter is easier to implement but unsuitable for certain 2D NMR acquisitions. The present communication discusses a new protocol that incorporates attractive attributes from both alternatives, imparting a continuous spatial encoding of the interactions yet yielding a phase modulation of the signal. This in turn enables a number of basic experiments that have shown particularly useful in the context of in vivo 2D NMR, including 2D J-resolved and 2D H,H-COSY spectroscopies. It also provides a route to achieving sensitivity-enhanced acquisitions for other homonuclear correlation experiments, such as ultrafast 2D TOCSY. The main features underlying this new spatial encoding protocol are derived, and its potential demonstrated with a series of phase-modulated homonuclear single-scan 2D NMR examples.
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Affiliation(s)
- Assaf Tal
- Department of Chemical Physics, Weizmann Institute of Science, 76100 Rehovot, Israel
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30
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Du W, Du W, Fan X, Foxley S, Zamora M, River JN, Culp RM, Karczmar GS. Comparison of high-resolution echo-planar spectroscopic imaging with conventional MR imaging of prostate tumors in mice. NMR IN BIOMEDICINE 2005; 18:285-92. [PMID: 15973657 DOI: 10.1002/nbm.954] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
High spectral and spatial resolution (HiSS) MRI of rodent tumors has previously been performed using conventional spectroscopic imaging to obtain images with improved contrast and anatomic detail. The work described here evaluates the use of much faster echo-planar spectroscopic imaging (EPSI) to acquire HiSS data from rodent tumor models of prostate cancer. A high-resolution EPSI pulse sequence was implemented on a 4.7 T Bruker scanner. Three-dimensional EPSI data were Fourier-transformed along the k-space and temporal (free-induction decay) axes to produce detailed water and fat spectra associated with each small image voxel. The data were used to generate images of spectral parameters, e.g. peak-height images for each small voxel. Two variants of EPSI were performed; gradient-echo or spin-echo excitation with EPSI readout. These imaging methods were tested in commonly used rodent prostate cancers, including seven mice implanted with non-metastatic AT2.1 (n=3) and metastatic AT3.1 (n=4) prostate tumors on the hind leg, and 10 mice implanted with LNCaP prostate cancers in situ. The peak-height images derived from EPSI datasets provide more detailed tumor anatomy, improved signal-to-noise and contrast-to-noise ratios compared with the gradient-echo or spin-echo images at all echo times. The results suggest that HiSS MRI data from small animal models of prostate cancer can be acquired using EPSI, and that this approach improves imaging of heterogeneous tissue and vascular environments inside the tumors compared with conventional MR techniques.
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Affiliation(s)
- Weiliang Du
- Department of Radiology, University of Chicago, Chicago, IL 60637, USA
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31
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Pucar D, Shukla-Dave A, Hricak H, Moskowitz CS, Kuroiwa K, Olgac S, Ebora LE, Scardino PT, Koutcher JA, Zakian KL. Prostate cancer: correlation of MR imaging and MR spectroscopy with pathologic findings after radiation therapy-initial experience. Radiology 2005; 236:545-53. [PMID: 15972335 PMCID: PMC2373272 DOI: 10.1148/radiol.2362040739] [Citation(s) in RCA: 178] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
PURPOSE To prospectively evaluate magnetic resonance (MR) imaging and MR spectroscopy for depiction of local prostate cancer recurrence after external-beam radiation therapy, with step-section pathologic findings as the standard of reference. MATERIALS AND METHODS Study received institutional approval, and written informed consent was obtained. Study was compliant with Health Insurance Portability and Accountability Act. Sextant biopsy, digital rectal examination, MR imaging, MR spectroscopy, and salvage radical prostatectomy with step-section pathologic examination were performed in nine patients with increasing prostate-specific antigen levels after external-beam radiation therapy. MR imaging criterion for tumor was a focal nodular region of reduced signal intensity at T2-weighted imaging. MR spectroscopic criteria for tumor were voxels with choline (Cho) plus creatine (Cr) to citrate (Cit) ratio ([Cho + Cr]/Cit) of at least 0.5 or voxels with detectable Cho and no Cit in the peripheral zone. Sensitivity and specificity of sextant biopsy, digital rectal examination, MR imaging, and MR spectroscopy were determined by using a prostate sextant as the unit of analysis. For feature analysis, MR imaging and MR spectroscopic findings were correlated with step-section pathologic findings. RESULTS MR imaging and MR spectroscopy showed estimated sensitivities of 68% and 77%, respectively, while sensitivities of biopsy and digital rectal examination were 48% and 16%, respectively. MR spectroscopy appears to be less specific (78%) than the other three tests, each of which had a specificity higher than 90%. MR spectroscopic feature analysis showed that a metabolically altered benign gland could be falsely identified as tumor by using MR spectroscopic criteria; further analysis of MR spectroscopic features did not lead to improved MR spectroscopic criteria for recurrent tumor. CONCLUSION In summary, MR imaging and MR spectroscopy may be more sensitive than sextant biopsy and digital rectal examination for sextant localization of cancer recurrence after external-beam radiation therapy.
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Affiliation(s)
- Darko Pucar
- Department of Radiology, Medical Physics, Epidemiology and Biostatistics, Urology, Pathology, and Medicine, Memorial Sloan-Kettering Cancer Center, 1275 York Ave, New York, NY 10021, USA
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32
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Schulte RF, Trabesinger AH, Boesiger P. Chemical-shift-selective filter for the in vivo detection of J-coupled metabolites at 3T. Magn Reson Med 2005; 53:275-81. [PMID: 15678545 DOI: 10.1002/mrm.20362] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A chemical-shift-selective filter (CSSF) was applied to the detection of J-coupled metabolites in the human brain. This filter is an acquisition-based technique that requires the chemical shifts (CS's) of different metabolites, but not their whole multiplet structures, to be resolved. The sequence is based on the 2D constant-time spin-echo experiment, which yields pure CS spectra in the indirect dimension. Localization is achieved through point-resolved spectroscopy (PRESS). The method enables unequivocal detection of glutamate and myo-inositol, both in vitro and in vivo in the human brain, at 3T.
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Affiliation(s)
- Rolf F Schulte
- Institute for Biomedical Engineering, University of Zurich and Swiss Federal Institute of Technology, Zurich, Switzerland
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33
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Kim DH, Margolis D, Xing L, Daniel B, Spielman D. In vivo prostate magnetic resonance spectroscopic imaging using two-dimensional J-resolved PRESS at 3 T. Magn Reson Med 2005; 53:1177-82. [PMID: 15844143 DOI: 10.1002/mrm.20452] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In vivo magnetic resonance spectroscopic imaging of the prostate using single-voxel and multivoxel two-dimensional (2D) J-resolved sequences is investigated at a main magnetic field strength of 3 T. Citrate, an important metabolite often used to aid the detection of prostate cancer in magnetic resonance spectroscopic exams, can be reliably detected along with the other metabolites using this method. We show simulations and measurements of the citrate metabolite using 2D J-resolved spectroscopy to characterize the spectral pattern. Furthermore, using spiral readout gradients, the single-voxel 2D J-resolved method is extended to provide the spatial distribution information as well all within a reasonable scan time (17 min). Phantom and in vivo data are presented to illustrate the multivoxel 2D J-resolved spiral chemical shift imaging sequence.
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Affiliation(s)
- Dong-hyun Kim
- Department of Radiology, Stanford University, CA 94305, USA.
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Sajda P, Du S, Brown TR, Stoyanova R, Shungu DC, Mao X, Parra LC. Nonnegative matrix factorization for rapid recovery of constituent spectra in magnetic resonance chemical shift imaging of the brain. IEEE TRANSACTIONS ON MEDICAL IMAGING 2004; 23:1453-65. [PMID: 15575404 DOI: 10.1109/tmi.2004.834626] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
We present an algorithm for blindly recovering constituent source spectra from magnetic resonance (MR) chemical shift imaging (CSI) of the human brain. The algorithm, which we call constrained nonnegative matrix factorization (cNMF), does not enforce independence or sparsity, instead only requiring the source and mixing matrices to be nonnegative. It is based on the nonnegative matrix factorization (NMF) algorithm, extending it to include a constraint on the positivity of the amplitudes of the recovered spectra. This constraint enables recovery of physically meaningful spectra even in the presence of noise that causes a significant number of the observation amplitudes to be negative. We demonstrate and characterize the algorithm's performance using 31P volumetric brain data, comparing the results with two different blind source separation methods: Bayesian spectral decomposition (BSD) and nonnegative sparse coding (NNSC). We then incorporate the cNMF algorithm into a hierarchical decomposition framework, showing that it can be used to recover tissue-specific spectra given a processing hierarchy that proceeds coarse-to-fine. We demonstrate the hierarchical procedure on 1H brain data and conclude that the computational efficiency of the algorithm makes it well-suited for use in diagnostic work-up.
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Affiliation(s)
- Paul Sajda
- Laboratory of Intelligent Imaging and Neural Computing, Department of Biomedical Engineering, Columbia University, 351 Engineering Terrace Building, Mail Code 8904, 1210 Amsterdam Ave., New York, NY 10027, USA.
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35
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Jung JA, Coakley FV, Vigneron DB, Swanson MG, Qayyum A, Weinberg V, Jones KD, Carroll PR, Kurhanewicz J. Prostate Depiction at Endorectal MR Spectroscopic Imaging: Investigation of a Standardized Evaluation System. Radiology 2004; 233:701-8. [PMID: 15564406 DOI: 10.1148/radiol.2333030672] [Citation(s) in RCA: 151] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To investigate the accuracy and interobserver variability of a standardized evaluation system for endorectal three-dimensional (3D) magnetic resonance (MR) spectroscopic imaging of the prostate. MATERIALS AND METHODS The human research committee approved the study, and all patients provided written informed consent. Endorectal MR imaging and MR spectroscopic imaging were performed in 37 patients before they underwent radical prostatectomy. For the 22 patients with good or excellent MR spectroscopic imaging data, step-section histopathologic tumor maps were used to identify spectroscopic voxels of unequivocally benign (n = 306) or malignant (n = 81) peripheral zone tissue. Two independent spectroscopists, unaware of all other findings, scored the spectra of the selected voxels by using a scale of 1 (benign) to 5 (malignant) that was based on standardized metabolic criteria. Descriptive statistical, receiver operating characteristics (ROC), and kappa statistical analyses of the data obtained by both readers were performed by using two definitions of cancer: one based on a voxel score of 3-5 and the other based on a score of 4 or 5. RESULTS The scoring system had good accuracy (74.2%-85.0%) in the differentiation between benign and malignant tissue voxels, with areas under the ROC curve of 0.89 for reader 1 and 0.87 for reader 2. Specificities of 84.6% and 89.3% were achieved when a voxel score of 4 or 5 was used to identify cancer, and sensitivities of 90% and 93% were achieved when a score of 3-5 was used to identify cancer. Readers demonstrated excellent interobserver agreement (kappa values, 0.79 and 0.80). CONCLUSION The good accuracy and excellent interobserver agreement achieved by using the standardized five-point scale to interpret peripheral zone metabolism demonstrate the potential effectiveness of using metabolic information to identify prostate cancer, and the clinical usefulness of this system warrants testing in prospective clinical trials of MR imaging combined with MR spectroscopic imaging.
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Affiliation(s)
- Juyoung A Jung
- Department of Radiology, University of California-San Francisco, San Francisco, CA 94143, USA
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36
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Hérigault G, Zoula S, Rémy C, Décorps M, Ziegler A. Multi-spin-echo J-resolved spectroscopic imaging without water suppression: application to a rat glioma at 7 T. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2004; 17:140-8. [PMID: 15517469 DOI: 10.1007/s10334-004-0060-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2004] [Revised: 07/02/2004] [Accepted: 07/20/2004] [Indexed: 10/26/2022]
Abstract
Two-dimensional J-resolved spectroscopy may be used to separate resonances which overlap in 1D NMR spectra. Coupled with spectroscopic imaging (SI), it would give unequivocal information on the distribution of such resonances. Multi-echo acquisition decreases the minimum experimental time of such 4D experiments. The water peak may be used for phase and chemical-shift reference. This study aimed to demonstrate the feasibility of J-resolved SI based on a multi-echo sequence and without water suppression, and its ability to separate the peaks for lactate and mobile lipid in a rat glioma. Experiments were performed on rat brain, without water suppression, at 7 T. The water signal was used for correcting the phase of the echoes. A FOCSY-like acquisition was used to collect the first part of the echoes at short echo times. Two different data processing methods were tested to overcome the problem of contaminations of metabolite signals by the intense water signal. Maps of N-acetylaspartate, choline, creatine, lactate and mobile lipids were obtained in vivo on a rat glioma in 70 min. The in-plane resolution was 2 mm2. The 2D spatially resolved, 2D J-resolved spectra enabled the separate mapping of lactate and mobile lipids.
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Affiliation(s)
- G Hérigault
- Laboratoire mixte INSERM U594, Université Joseph Fourier "Neuroimagerie fonctionnelle et métabolique", Laboratoire de Recherche Conventionné (30 V) du CEA, Centre Hospitalier Universitaire, pavillon, BP 217, 38043, Grenoble Cedex, France
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37
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Rajesh A, Coakley FV. MR imaging and MR spectroscopic imaging of prostate cancer. Magn Reson Imaging Clin N Am 2004; 12:557-79, vii. [PMID: 15271371 DOI: 10.1016/j.mric.2004.03.011] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The primary indication for prostate MR and MR spectroscopic imaging is evaluating men with newly diagnosed prostate cancer who are deciding whether to undergo surgery or radiotherapy. Other applications of MR and MR spectroscopic imaging in prostate cancer are not defined fully. Areas of research include volumetric localization of prostate cancer, in vivo MR spectroscopic imaging at high field strength, in vitro MR spectroscopic imaging at very high field strength, novel spectroscopic markers of malignancy,and interventional MR guidance of biopsy and therapy. MR spectroscopic imaging remains a relatively novel technique, and successful implementation is demanding. Nonetheless, only MR and MR spectroscopic imaging allow structural and metabolic evaluation of prostate cancer location, aggressiveness, and stage, and MR imaging provides clinically and therapeutically relevant information on prostatic and periprostatic anatomy.
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Affiliation(s)
- Arumugam Rajesh
- University Hospitals of Leicester, Leicester General Hospital, Gwendolen Road, Leicester LE 5 4PN, United Kingdom
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38
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Wu CL, Taylor JL, He W, Zepeda AG, Halpern EF, Bielecki A, Gonzalez RG, Cheng LL. Proton high-resolution magic angle spinning NMR analysis of fresh and previously frozen tissue of human prostate. Magn Reson Med 2004; 50:1307-11. [PMID: 14648580 DOI: 10.1002/mrm.10645] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The previously observed improvement in spectral resolution of tissue proton NMR with high-resolution magic angle spinning (HRMAS) was speculated to be due largely to freeze-thawing artifacts resulting from tissue storage. In this study, 12 human prostate samples were analyzed on a 14.1T spectrometer at 3 degrees C, with HRMAS rates of 600 and 700 Hz. These samples were measured fresh and after they were frozen for 12-16 hr prior to thawing. The spectral linewidths measured from fresh and previously frozen samples were identical for all metabolites except citrate and acetate. The metabolite intensities of fresh and freeze-thawed samples depend on the quantification procedures used; however, in this experiment the differences of means were <30%. As expected, it was found that tissue storage impacts tissue quality for pathological analysis, and HRMAS conditions alone are not sufficiently destructive to impair pathological evaluation. Furthermore, although storage conditions affect absolute metabolite concentrations in NMR analysis, relative metabolite concentrations are less affected.
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Affiliation(s)
- Chin-Lee Wu
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
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39
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Swanson MG, Vigneron DB, Tabatabai ZL, Males RG, Schmitt L, Carroll PR, James JK, Hurd RE, Kurhanewicz J. Proton HR-MAS spectroscopy and quantitative pathologic analysis of MRI/3D-MRSI-targeted postsurgical prostate tissues. Magn Reson Med 2004; 50:944-54. [PMID: 14587005 DOI: 10.1002/mrm.10614] [Citation(s) in RCA: 163] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Proton high-resolution magic angle spinning ((1)H HR-MAS) NMR spectroscopy and quantitative histopathology were performed on the same 54 MRI/3D-MRSI-targeted postsurgical prostate tissue samples. Presurgical MRI/3D-MRSI targeted healthy and malignant prostate tissues with an accuracy of 81%. Even in the presence of substantial tissue heterogeneity, distinct (1)H HR-MAS spectral patterns were observed for different benign tissue types and prostate cancer. Specifically, healthy glandular tissue was discriminated from prostate cancer based on significantly higher levels of citrate (P = 0.04) and polyamines (P = 0.01), and lower (P = 0.02) levels of the choline-containing compounds choline, phosphocholine (PC), and glycerophosphocholine (GPC). Predominantly stromal tissue lacked both citrate and polyamines, but demonstrated significantly (P = 0.01) lower levels of choline compounds than cancer. In addition, taurine, myo-inositol, and scyllo-inositol were all higher in prostate cancer vs. healthy glandular and stromal tissues. Among cancer samples, larger increases in choline, and decreases in citrate and polyamines (P = 0.05) were observed with more aggressive cancers, and a MIB-1 labeling index correlated (r = 0.62, P = 0.01) with elevated choline. The elucidation of spectral patterns associated with mixtures of different prostate tissue types and cancer grades, and the inclusion of new metabolic markers for prostate cancer may significantly improve the clinical interpretation of in vivo prostate MRSI data.
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Affiliation(s)
- Mark G Swanson
- Department of Radiology, University of California-San Francisco, San Francisco, California 94143-1290, USA.
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40
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Howe FA, Opstad KS. 1H MR spectroscopy of brain tumours and masses. NMR IN BIOMEDICINE 2003; 16:123-131. [PMID: 12884355 DOI: 10.1002/nbm.822] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Accurate diagnosis is essential for optimum management and treatment of patients with brain tumours. Proton magnetic resonance spectroscopy ((1)H MRS) provides information non-invasively on tumour biochemistry and has been shown to provide important additional information to that obtained by conventional radiology. We review the current status of (1)H MRS in classifying brain tumour type and grade, for monitoring response to therapy and progression to higher grade, and as a molecular imaging technique for determining tumour extent for treatment planning.
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Affiliation(s)
- Franklyn A Howe
- Cancer Research UK Biomedical Magnetic Resonance Research Group, Department of Basic Medical Sciences, St George's Hospital Medical School, London, UK.
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41
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Kurhanewicz J, Swanson MG, Nelson SJ, Vigneron DB. Combined magnetic resonance imaging and spectroscopic imaging approach to molecular imaging of prostate cancer. J Magn Reson Imaging 2002; 16:451-63. [PMID: 12353259 PMCID: PMC1978163 DOI: 10.1002/jmri.10172] [Citation(s) in RCA: 289] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Magnetic resonance spectroscopic imaging (MRSI) provides a noninvasive method of detecting small molecular markers (historically the metabolites choline and citrate) within the cytosol and extracellular spaces of the prostate, and is performed in conjunction with high-resolution anatomic imaging. Recent studies in pre-prostatectomy patients have indicated that the metabolic information provided by MRSI combined with the anatomical information provided by MRI can significantly improve the assessment of cancer location and extent within the prostate, extracapsular spread, and cancer aggressiveness. Additionally, pre- and post-therapy studies have demonstrated the potential of MRI/MRSI to provide a direct measure of the presence and spatial extent of prostate cancer after therapy, a measure of the time course of response, and information concerning the mechanism of therapeutic response. In addition to detecting metabolic biomarkers of disease behavior and therapeutic response, MRI/MRSI guidance can improve tissue selection for ex vivo analysis. High-resolution magic angle spinning ((1)H HR-MAS) spectroscopy provides a full chemical analysis of MRI/MRSI-targeted tissues prior to pathologic and immunohistochemical analyses of the same tissue. Preliminary (1)H HR-MAS spectroscopy studies have already identified unique spectral patterns for healthy glandular and stromal tissues and prostate cancer, determined the composition of the composite in vivo choline peak, and identified the polyamine spermine as a new metabolic marker of prostate cancer. The addition of imaging sequences that provide other functional information within the same exam (dynamic contrast uptake imaging and diffusion-weighted imaging) have also demonstrated the potential to further increase the accuracy of prostate cancer detection and characterization.
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Affiliation(s)
- John Kurhanewicz
- Magnetic Resonance Science Center, Department of Radiology, University of California-San Francisco, San Francisco, California 94143-1290, USA.
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42
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Yue K, Marumoto A, Binesh N, Thomas MA. 2D JPRESS of human prostates using an endorectal receiver coil. Magn Reson Med 2002; 47:1059-64. [PMID: 12111951 DOI: 10.1002/mrm.10160] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A localized 2D J-resolved (JPRESS) MR spectroscopic sequence was evaluated in human prostates in vivo. Voxels of typically 2 ml were placed in the peripheral zone of the prostate. Eight healthy volunteers, three subjects with benign prostatic hyperplasia, and three patients with prostatic cancer were scanned on a 1.5T MR scanner, using a body coil for RF transmission and a pelvic phased-array coil combined with a disposable endorectal coil for signal reception. The total acquisition time for a 2D JPRESS spectrum was approximately 17 min. A major advantage of the endorectal 2D JPRESS was the ability to resolve the peaks of choline-containing compounds and those of spermine unequivocally. Spectral results clearly showed the biochemical changes in cancer and benign compared to healthy prostates, in conformity with ex vivo biochemical findings. The preliminary results suggest that the endorectal 2D JPRESS could be successfully implemented for the diagnostic examination of human prostates. .
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Affiliation(s)
- Kenneth Yue
- Department of Radiological Sciences, School of Medicine, University of California, Los Angeles, California, USA
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Kwock L, Smith JK, Castillo M, Ewend MG, Cush S, Hensing T, Varia M, Morris D, Bouldin TW. Clinical applications of proton MR spectroscopy in oncology. Technol Cancer Res Treat 2002; 1:17-28. [PMID: 12614173 DOI: 10.1177/153303460200100103] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Proton magnetic resonance spectroscopy (H1-MRS) has been increasingly receiving more attention from radiologists, neurosurgeons, radiation and medical oncologists in the "in situ" clinical evaluation of human tumors. The utilization of H1-MRS, especially in human brain tumors, coupled to both routine magnetic resonance imaging (MRI) and functional MRI techniques provides greater information concerning tumor grading and extension and characterization of the normal surrounding tissue than what is possible with any other imaging technique alone. In this paper, we will review the current status of proton MR spectroscopy with emphasis on its clinical utility to diagnose tumors, its utility in planning surgical and radiation therapy interventions, and in its use in monitoring tumor treatment.
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Affiliation(s)
- Lester Kwock
- Department of Radiology, Lineberger Comprehensive Cancer Center, University of North Carolina, School of Medicine, Chapel Hill NC 27599-7515, USA.
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Gibbs P, Tozer DJ, Liney GP, Turnbull LW. Comparison of quantitative T2 mapping and diffusion-weighted imaging in the normal and pathologic prostate. Magn Reson Med 2001; 46:1054-8. [PMID: 11746568 DOI: 10.1002/mrm.1298] [Citation(s) in RCA: 172] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In this study, diffusion-weighted images of the human prostate were successfully obtained, enabling quantification of apparent diffusion coefficients (ADCs) in normal and pathologic regions. A dual acquisition fast spin-echo sequence was used for accurate T2 calculation. T2 values were significantly higher in the peripheral zone than the central gland (P = 0.015). No significant correlations were found in either normal or pathologic tissue between ADC values and relaxation rates for all three gradient directions and the orientationally averaged water diffusion coefficient. Evidence suggesting that diffusional anisotropy is present in normal prostatic tissue is also detailed, with significant differences noted between the z-component and both the x- and y-components of the ADC for peripheral zone (P < 0.040) and central gland (P < 0.001).
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Affiliation(s)
- P Gibbs
- Academic Department of Radiology, University of Hull, Hull, UK.
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