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Singh B, Yadav R, Kumar T, Kawlra S. Revisiting Concepts of Magnetic Resonance Spectroscopy in the Evaluation of Brain Lesions: An Institutional Experience. ASIAN JOURNAL OF ONCOLOGY 2022. [DOI: 10.1055/s-0042-1750709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
Abstract
Abstract
Objective Magnetic resonance spectroscopy (MRS) has emerged as a technique due to its ability to characterize the metabolite constituent of any lesion. We have evaluated magnetic resonance (MR) spectral patterns in different neoplastic brain lesions, using the ability of MRS in grading of gliomas. MRS also helps in differentiating between high-grade glioma and metastases.
Method A retrospective observational study in histologically confirmed cases of brain neoplasms in which MRS was performed as a part of preoperative MR imaging. The pattern of metabolite peak was observed and means with standard deviation of different metabolite ratios (choline/creatine, choline/N-acetylaspartate [NAA], NAA/creatine) were calculated for different tumors. Analysis was done to see statistically significant differences in metabolite ratios of different grades of gliomas and to differentiate high-grade gliomas from metastases.
Result A total of 61 cases with brain tumor were included in the study. Of which, 20 cases were of gliomas, 11 metastases, 9 meningiomas, 4 dysembryoplastic neuroepithelial tumors, 6 pituitary macroadenomas, 4 trigeminal schwannomas, 3 craniopharyngiomas, 2 acoustic schwannomas, and 2 medulloblastomas. Statistically significant differences in ratios of metabolite peaks were noted between different grades of gliomas and for high-grade glioma versus metastases.
Conclusion MRS compliments the MR imaging and stands out as problem-solving method to distinguish neoplastic lesions in selected cases and also has a role in grading of gliomas and in differentiation of types of malignancies.
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Affiliation(s)
- Bhanupriya Singh
- Department of Radiodiagnosis, Dr. Ram Manohar Lohiya Institute of Medical Sciences, Lucknow, Uttar Pradesh, India
| | - Rajlakshmi Yadav
- Department of Radiodiagnosis, Dr. Ram Manohar Lohiya Institute of Medical Sciences, Lucknow, Uttar Pradesh, India
| | - Tushant Kumar
- Department of Radiodiagnosis, Dr. Ram Manohar Lohiya Institute of Medical Sciences, Lucknow, Uttar Pradesh, India
| | - Sandeep Kawlra
- Department of Radiodiagnosis, Medanta Pvt Limited, Lucknow, Uttar Pradesh, India
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Abstract
Food and Drug Administration approval of 7T MR imaging allows ultrahigh-field neuroimaging to extend from the research realm into the clinical realm. Increased signal is clinically advantageous for smaller voxels and thereby high spatial resolution imaging, with additional advantages of increased tissue contrast. Susceptibility, time-of-flight signal, and blood oxygen level-dependent signal also have favorable clinical benefit from 7T. This article provides a survey of clinical cases showcasing some advantages of 7T.
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Komanchuk J, Martin DA, Killam R, Eccles R, Brindle ME, Khanafer I, Joffe AR, Blackwood J, Yu W, Gupta P, Sethi S, Moorjani V, Thompson G. Magnetic Resonance Imaging Provides Useful Diagnostic Information Following Equivocal Ultrasound in Children With Suspected Appendicitis. Can Assoc Radiol J 2021; 72:797-805. [PMID: 33648355 DOI: 10.1177/0846537121993797] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
PURPOSE In Canada, ultrasonography is the primary imaging modality for children with suspected appendicitis, yet equivocal studies are common. Magnetic resonance imaging provides promise as an adjunct imaging strategy. The primary objective of this study was to determine the proportion of children with suspected appendicitis and equivocal ultrasound where magnetic resonance imaging determined a diagnosis. METHODS A prospective consecutive cohort of children aged 5-17 years presenting to a tertiary pediatric Emergency Department with suspected appendicitis were enrolled. Participants underwent diagnostic and management strategies according to our local suspected appendicitis pathway, followed by magnetic resonance (Siemens Avanto 1.5 Tesla) imaging. Sub-specialty pediatric radiologists reported all images. RESULTS Magnetic resonance imaging was performed in 101 children with suspected appendicitis. The mean age was 11.9 (SD 3.4) years and median Pediatric Appendicitis Score was 6 [IQR 4,8]. Ultrasonography was completed in 98/101 (97.0%). Of 53/98 (54.1%) with equivocal ultrasound, magnetic resonance imaging provided further diagnostic information in 41 (77.4%; 10 positive, 31 negative; 12 remained equivocal). Secondary findings of appendicitis on magnetic resonance imaging in children with equivocal ultrasound included abdominal free fluid (24, 45.3%), peri-appendiceal fluid (12, 22.6%), intraluminal appendiceal fluid (9, 17.0%), fat stranding (8, 15.1%), appendicolith (2, 3.8%), and peri-appendiceal abscess (1, 1.9%). The observed agreement between magnetic resonance imaging results and final diagnosis was 94.9% (kappa = 0.89).
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Affiliation(s)
- Jelena Komanchuk
- Faculty of Nursing, University of Calgary, Calgary, Alberta, Canada
| | - Dori-Ann Martin
- Department of Pediatrics, University of Calgary, Calgary, Alberta, Canada
| | - Rory Killam
- Department of Pediatrics, University of Calgary, Calgary, Alberta, Canada
| | - Robin Eccles
- Department of Surgery, University of Calgary, Calgary, Alberta, Canada
| | - Mary E Brindle
- Department of Surgery, University of Calgary, Calgary, Alberta, Canada
| | - Ijab Khanafer
- Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada
| | - Ari R Joffe
- Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada
| | - Jaime Blackwood
- Department of Pediatrics, University of Calgary, Calgary, Alberta, Canada
| | - Weiming Yu
- Department of Pathology, University of Calgary, Alberta, Canada
| | - Priya Gupta
- Department of Radiology, University of Calgary, Calgary, Alberta, Canada
| | - Sanjay Sethi
- Department of Radiology, University of Calgary, Calgary, Alberta, Canada
| | - Vijay Moorjani
- Department of Radiology, University of Calgary, Calgary, Alberta, Canada
| | - Graham Thompson
- Department of Pediatrics, University of Calgary, Calgary, Alberta, Canada.,Department of Emergency Medicine, University of Calgary, Calgary, Alberta, Canada
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Lin H, Müller-Bardorff M, Gathmann B, Brieke J, Mothes-Lasch M, Bruchmann M, Miltner WHR, Straube T. Stimulus arousal drives amygdalar responses to emotional expressions across sensory modalities. Sci Rep 2020; 10:1898. [PMID: 32024891 PMCID: PMC7002496 DOI: 10.1038/s41598-020-58839-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 12/23/2019] [Indexed: 11/08/2022] Open
Abstract
The factors that drive amygdalar responses to emotionally significant stimuli are still a matter of debate - particularly the proneness of the amygdala to respond to negatively-valenced stimuli has been discussed controversially. Furthermore, it is uncertain whether the amygdala responds in a modality-general fashion or whether modality-specific idiosyncrasies exist. Therefore, the present functional magnetic resonance imaging (fMRI) study systematically investigated amygdalar responding to stimulus valence and arousal of emotional expressions across visual and auditory modalities. During scanning, participants performed a gender judgment task while prosodic and facial emotional expressions were presented. The stimuli varied in stimulus valence and arousal by including neutral, happy and angry expressions of high and low emotional intensity. Results demonstrate amygdalar activation as a function of stimulus arousal and accordingly associated emotional intensity regardless of stimulus valence. Furthermore, arousal-driven amygdalar responding did not depend on the visual and auditory modalities of emotional expressions. Thus, the current results are consistent with the notion that the amygdala codes general stimulus relevance across visual and auditory modalities irrespective of valence. In addition, whole brain analyses revealed that effects in visual and auditory areas were driven mainly by high intense emotional facial and vocal stimuli, respectively, suggesting modality-specific representations of emotional expressions in auditory and visual cortices.
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Affiliation(s)
- Huiyan Lin
- Institute of Applied Psychology, School of Public Administration, Guangdong University of Finance, 510521, Guangzhou, China.
- Institute of Medical Psychology and Systems Neuroscience, University of Muenster, 48149, Muenster, Germany.
| | - Miriam Müller-Bardorff
- Institute of Medical Psychology and Systems Neuroscience, University of Muenster, 48149, Muenster, Germany
| | - Bettina Gathmann
- Institute of Medical Psychology and Systems Neuroscience, University of Muenster, 48149, Muenster, Germany
| | - Jaqueline Brieke
- Institute of Medical Psychology and Systems Neuroscience, University of Muenster, 48149, Muenster, Germany
| | - Martin Mothes-Lasch
- Institute of Medical Psychology and Systems Neuroscience, University of Muenster, 48149, Muenster, Germany
| | - Maximilian Bruchmann
- Institute of Medical Psychology and Systems Neuroscience, University of Muenster, 48149, Muenster, Germany
| | - Wolfgang H R Miltner
- Department of Clinical Psychology, Friedrich Schiller University of Jena, 07743, Jena, Germany
| | - Thomas Straube
- Institute of Medical Psychology and Systems Neuroscience, University of Muenster, 48149, Muenster, Germany
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Lyall AE, Savadjiev P, Shenton ME, Kubicki M. Insights into the Brain: Neuroimaging of Brain Development and Maturation. JOURNAL OF NEUROIMAGING IN PSYCHIATRY & NEUROLOGY 2016; 1:10-19. [PMID: 28620654 PMCID: PMC5469407 DOI: 10.17756/jnpn.2016-003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The study of how the human brain develops has always been a challenge and an interest to the scientific community. In recent years, new evidence has suggested that many neuropsychiatric disorders may originate from aberrations early in development. This discovery necessitates the application of methodologies that make possible the investigation of human brain development in vivo and across the lifespan. In this commentary, we present evidence that the advent of structural neuroimaging has specifically and significantly contributed critical information about the developmental trajectories of postnatal human brain development that would otherwise not have been possible. We believe that this is particularly relevant to present day research as it has become increasingly clear that growth trajectories within the brain might serve as an endophenotype for a number of factors, ranging from IQ to psychiatric illness. We highlight seminal early works that helped to jumpstart the field of developmental neuroimaging and which inspired incredible new advances in neuroimaging methodologies that are being developed and applied in the field today.
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Affiliation(s)
- Amanda E Lyall
- Psychiatry Neuroimaging Laboratory, Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Peter Savadjiev
- Psychiatry Neuroimaging Laboratory, Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Martha E Shenton
- Psychiatry Neuroimaging Laboratory, Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,VA Boston Healthcare System, Brockton, MA, USA
| | - Marek Kubicki
- Psychiatry Neuroimaging Laboratory, Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.,Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
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6
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Dula AN, Pawate S, Dortch RD, Barry RL, George-Durrett KM, Lyttle BD, Dethrage LM, Gore JC, Smith SA. Magnetic resonance imaging of the cervical spinal cord in multiple sclerosis at 7T. Mult Scler 2015. [PMID: 26209591 DOI: 10.1177/1352458515591070] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND The clinical course of multiple sclerosis (MS) is mainly attributable to cervical and upper thoracic spinal cord dysfunction. High-resolution, 7T anatomical imaging of the cervical spinal cord is presented. Image contrast between gray/white matter and lesions surpasses conventional, clinical T1- and T2-weighted sequences at lower field strengths. OBJECTIVE To study the spinal cord of healthy controls and patients with MS using magnetic resonance imaging at 7T. METHODS Axial (C2-C5) T1- and T2*-weighted and sagittal T2*-/spin-density-weighted images were acquired at 7T in 13 healthy volunteers (age 22-40 years), and 15 clinically diagnosed MS patients (age 19-53 years, Extended Disability Status Scale, (EDSS) 0-3) in addition to clinical 3T scans. In healthy volunteers, a high-resolution multi-echo gradient echo scan was obtained over the same geometry at 3T. Evaluation included signal and contrast to noise ratios and lesion counts for healthy and patient volunteers, respectively. RESULTS/CONCLUSION High-resolution images at 7T exceeded resolutions reported at lower field strengths. Gray and white matter were sharply demarcated and MS lesions were more readily visualized at 7T compared to clinical acquisitions, with lesions apparent at both fields. Nerve roots were clearly visualized. White matter lesion counts averaged 4.7 vs 3.1 (52% increase) per patient at 7T vs 3T, respectively (p=0.05).
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Affiliation(s)
- Adrienne N Dula
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, USA/Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, USA
| | - Siddharama Pawate
- Department of Neuroscience, Vanderbilt University Medical Center, USA
| | - Richard D Dortch
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, USA/Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, USA
| | - Robert L Barry
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, USA/Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, USA
| | | | - Bailey D Lyttle
- Department of Neuroscience, Vanderbilt University Medical Center, USA
| | - Lindsey M Dethrage
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, USA
| | - John C Gore
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, USA/Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, USA/Department of Biomedical Engineering, Vanderbilt University Medical Center, USA
| | - Seth A Smith
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, USA/Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, USA/Department of Biomedical Engineering, Vanderbilt University Medical Center, USA
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Tocchio S, Kline-Fath B, Kanal E, Schmithorst VJ, Panigrahy A. MRI evaluation and safety in the developing brain. Semin Perinatol 2015; 39:73-104. [PMID: 25743582 PMCID: PMC4380813 DOI: 10.1053/j.semperi.2015.01.002] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Magnetic resonance imaging (MRI) evaluation of the developing brain has dramatically increased over the last decade. Faster acquisitions and the development of advanced MRI sequences, such as magnetic resonance spectroscopy (MRS), diffusion tensor imaging (DTI), perfusion imaging, functional MR imaging (fMRI), and susceptibility-weighted imaging (SWI), as well as the use of higher magnetic field strengths has made MRI an invaluable tool for detailed evaluation of the developing brain. This article will provide an overview of the use and challenges associated with 1.5-T and 3-T static magnetic fields for evaluation of the developing brain. This review will also summarize the advantages, clinical challenges, and safety concerns specifically related to MRI in the fetus and newborn, including the implications of increased magnetic field strength, logistics related to transporting and monitoring of neonates during scanning, and sedation considerations, and a discussion of current technologies such as MRI conditional neonatal incubators and dedicated small-foot print neonatal intensive care unit (NICU) scanners.
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Affiliation(s)
- Shannon Tocchio
- Pediatric Imaging Research Center, Department of Radiology Children’s Hospital of Pittsburgh of UPMC, Pittsburgh, PA University of Pittsburgh Medical Center, Pittsburgh, PA
| | - Beth Kline-Fath
- Department of Radiology Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
| | - Emanuel Kanal
- Director, Magnetic Resonance Services; Professor of Neuroradiology; Department of Radiology, University of Pittsburgh Medical Center (UPMC)
| | - Vincent J. Schmithorst
- Pediatric Imaging Research Center, Department of Radiology Children’s Hospital of Pittsburgh of UPMC, Pittsburgh, PA University of Pittsburgh Medical Center, Pittsburgh, PA
| | - Ashok Panigrahy
- Pediatric Imaging Research Center, Department of Radiology Children׳s Hospital of Pittsburgh of UPMC, University of Pittsburgh Medical Center, Pittsburgh, PA.
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Study on a method to improve T1 image contrast by the subtraction technique for 3.0 T brain examination. Clin Imaging 2014; 38:91-5. [DOI: 10.1016/j.clinimag.2013.10.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Revised: 09/27/2013] [Accepted: 10/29/2013] [Indexed: 11/22/2022]
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9
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Moon WJ, Kim HJ, Roh HG, Choi JW, Han SH. Fluid-attenuated inversion recovery hypointensity of the pulvinar nucleus of patients with Alzheimer disease: its possible association with iron accumulation as evidenced by the t2(*) map. Korean J Radiol 2012; 13:674-83. [PMID: 23118565 PMCID: PMC3484287 DOI: 10.3348/kjr.2012.13.6.674] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Accepted: 05/29/2012] [Indexed: 12/21/2022] Open
Abstract
OBJECTIVE We hypothesized that prominent pulvinar hypointensity in brain MRI represents the disease process due to iron accumulation in Alzheimer disease (AD). We aimed to determine whether or not the pulvinar signal intensity (SI) on the fluid-attenuated inversion recovery (FLAIR) sequences at 3.0T MRI differs between AD patients and normal subjects, and also whether the pulvinar SI is correlated with the T2(*) map, an imaging marker for tissue iron, and a cognitive scale. MATERIALS AND METHODS Twenty one consecutive patients with AD and 21 age-matched control subjects were prospectively included in this study. The pulvinar SI was assessed on the FLAIR image. We measured the relative SI ratio of the pulvinar to the corpus callosum. The T2(*) values were calculated from the T2(*) relaxometry map. The differences between the two groups were analyzed, by using a Student t test. The correlation between the measurements was assessed by the Pearson's correlation test. RESULTS As compared to the normal white matter, the FLAIR signal intensity of the pulvinar nucleus was significantly more hypointense in the AD patients than in the control subjects (p < 0.01). The pulvinar T2(*) was shorter in the AD patients than in the control subjects (51.5 ± 4.95 ms vs. 56.5 ± 5.49 ms, respectively, p = 0.003). The pulvinar SI ratio was strongly correlated with the pulvinar T2(*) (r = 0.745, p < 0.001). When controlling for age, only the pulvinar-to-CC SI ratio was positively correlated with that of the Mini-Mental State Examination (MMSE) score (r = 0.303, p < 0.050). Conversely, the pulvinar T2(*) was not correlated with the MMSE score (r = 0.277, p = 0.080). CONCLUSION The FLAIR hypointensity of the pulvinar nucleus represents an abnormal iron accumulation in AD and may be used as an adjunctive finding for evaluating AD.
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Affiliation(s)
- Won-Jin Moon
- Department of Radiology, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul 143-792, Korea
| | - Hee-Jin Kim
- Department of Neurology, Hanyang University Medical Center, Hanyang University School of Medicine, Seoul 133-791, Korea
- Department of Neurology, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul 143-792, Korea
| | - Hong Gee Roh
- Department of Radiology, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul 143-792, Korea
| | - Jin Woo Choi
- Department of Radiology, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul 143-792, Korea
| | - Seol-Heui Han
- Department of Neurology, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul 143-792, Korea
- Center for Geriatric Neuroscience Research, Konkuk University School of Medicine, Seoul 143-792, Korea
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Abstract
Magnetic resonance (MR) imaging at 3 T has proved superior to 1.5 T in the brain for detecting numerous pathologic entities including hemosiderin, tiny metastases, subtle demyelinating plaques, active demyelinating plaques, and some epileptogenic foci, as well as small aneurysms with MR angiography. 3 T is superior to most advanced imaging techniques including diffusion, diffusion tensor imaging, perfusion, spectroscopy and functional MR imaging. The increased signal/noise ratio at 3 T permits higher spatial resolution. Initially spine imaging at 3 T proved more difficult with less successful results. During the past 7 years, technological advances in magnet and surface coil design as well as improved radio frequency transmitters and pulse sequence design in combination with the large body of knowledge accrued by radiologists and physicists during a nine year experience with clinical imaging of the spine with the doubled B0, has resulted in 3 T MRI of the spine achieving a reputation similar to that for brain imaging.
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Affiliation(s)
- Marc Shapiro
- NeuroImaging Institute of Winter Park, 2111 Glenwood Drive, Winter Park, FL 32792, USA.
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12
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Dahmoush HM, Vossough A, Roberts TPL. Pediatric high-field magnetic resonance imaging. Neuroimaging Clin N Am 2012; 22:297-313, xi. [PMID: 22548934 DOI: 10.1016/j.nic.2012.02.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
High-field 3 T magnetic resonance (MR) imaging provides greater signal-to-noise ratio (SNR) compared with 1.5 T systems. Various MR imaging clinical applications in children can benefit from improvements resulting from this increased SNR. High-resolution imaging of the brain, arterial spin labeling perfusion imaging, diffusion imaging, MR spectroscopy, and imaging of small anatomic parts are some areas in which these improvements can increase our clinical diagnostic capabilities. However, challenges inherent to 3 T imaging become more relevant in children. The use of 3 T imaging in children has allowed better diagnostic efficacy in neuroimaging, but certain technique modifications may be required for optimal imaging.
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Affiliation(s)
- Hisham M Dahmoush
- Neuroradiology Section, Department of Radiology, Children's Hospital of Philadelphia, Wood 2115, 324 South 34th Street, Philadelphia, PA 19104, USA
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Kilsdonk ID, de Graaf WL, Barkhof F, Wattjes MP. Inflammation high-field magnetic resonance imaging. Neuroimaging Clin N Am 2012; 22:135-57, ix. [PMID: 22548925 DOI: 10.1016/j.nic.2012.02.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Multiple sclerosis (MS) is the most common inflammatory demyelinating disorder of the central nervous system (CNS). MS has been subject to high-field magnetic resonance (MR) imaging research to a great extent during the past years, and much data has been collected that might be helpful in the investigation of other inflammatory CNS disorders. This article reviews the value of high-field MR imaging in examining inflammatory MS abnormalities. Furthermore, possibilities and challenges for the future of high-field MR imaging in MS are discussed.
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Affiliation(s)
- Iris D Kilsdonk
- Department of Radiology, VU University Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands
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14
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Abstract
Head and neck imaging has benefited from 1.5 T magnetic resonance (MR) imaging, providing faster sequences, better soft tissue evaluation, and 3-axis imaging, with less radiation and iodine-based contrast injection. The US Food and Drug Administration has approved human MR imaging at high-field strength up to 4 T in clinical practice. 3 T MR imaging has become widely available, with the hope of significant advance in the evaluation of the head and neck region. This article reviews the benefits, disadvantages, and challenges of high-field imaging of the head and neck region, focusing on the imaging of head and neck cancer.
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15
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Lövblad KO, Haller S, Pereira VM. Stroke: high-field magnetic resonance imaging. Neuroimaging Clin N Am 2012; 22:191-205, x. [PMID: 22548928 DOI: 10.1016/j.nic.2012.02.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Diagnostic modalities for the diagnosis of acute stroke have increased in number and quality. Magnetic resonance imaging has increasingly become a central tool for the management of patients with stroke. New sequences, such as diffusion and perfusion, provide insight into the infarcted core and the hypoperfused brain. The use of higher magnetic fields allows us to gain in signal strength, which can be used to improve imaging speed and/or resolution. Recent additional sequences allow perfusion without contrast and susceptibility-weighted imaging can help identify early bleeding. These new techniques should provide more information about the on going ischemic process.
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Affiliation(s)
- Karl-Olof Lövblad
- Division of Neuroradiology, Department of Imaging and Medical Informatics, Geneva University Hospitals HUG, 4 rue Gabrielle-Perret-Gentil, 1211 Geneva, Switzerland.
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de Backer ME, Nabuurs RJA, van Buchem MA, van der Weerd L. MR-based molecular imaging of the brain: the next frontier. AJNR Am J Neuroradiol 2010; 31:1577-83. [PMID: 20864520 DOI: 10.3174/ajnr.a2264] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In the foreseeable future, the MI field could greatly assist neuroradiologists. Reporter molecules provide information on specific molecular or cellular events that could not only aid diagnosis but potentially differentiate stages of disorders and treatments. To accomplish this, reporter molecules literally need to pass a barrier, the BBB, which is designed to repel nonessential molecules from the brain. Although this is not a trivial task, several transport systems could be tricked into guiding molecules into the brain. The noninvasive nature in conjunction with a wide availability makes MR imaging particularly suitable for longitudinal neurologic imaging studies. This review explains the principles of MR imaging contrast, delineates different types of reporter molecules, and describes strategies to transport reporters into the brain. It also discusses recent advances in MR imaging hardware, pulse sequences, the development of targeted reporter probes, and future directions of the MR neuroimaging field.
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Affiliation(s)
- M E de Backer
- Molecular Imaging Laboratories, Leiden, the Netherlands
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Nakato K, Hiai Y, Tomiguchi S. [A fundamental study of non-contrast enhanced MR angiography using ECG gated-3D fast spin echo at 3.0 T]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2010; 66:863-9. [PMID: 20953101 DOI: 10.6009/jjrt.66.863] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Contrast-enhanced magnetic resonance angiography (CE-MRA) is frequently performed in body and extremity studies because of its superior ability to detect the vascular stenosis. However, nephrotoxicity of the contrast medium has been emphasized in recent years. Non-contrast MRA using the three-dimensional electrocardiogram-synchronized fast spin echo method (FBI, NATIVE and TRANCE) is recommended as a substitute for CE-MRA. There are a few reports in the literature that evaluate the detectability of vascular stenosis using non-contrast MRA on 3.0 T MRI. The purpose of this study was to evaluate the detectability of vascular stenosis using non-contrast MRA at 3.0 T with an original vascular phantom. The vascular phantom consisted of silicon tubes. 30% and 70% stenosis of luminal diameter were made. Each silicon tube connected a pump producing a pulsatile flow. A flowing material to was used in this study to show the similarity of the intensity to blood on MRI. MRA without a contrast medium (NATIVE sequence) were performed in the vascular phantom by changing the image matrix, static magnetic field strength and flow velocity. In addition, the NATIVE sequence was used with or without flow compensation. Vascular stenosis was quantitatively estimated by measurement of the signal intensities in non-contrast MRA images. MRA with NATIVE sequence demonstrated an accurate estimation of 30% vascular stenosis at slow flow velocity. However, 30% stenosis was overestimated in cases of high flow velocity. Estimation was improved by using a flow compensation sequence. 70% stenosis was overestimated on MRA with NATIVE sequence. Estimation of 70% stenosis was improved by using a flow compensation sequence. Accurate estimation of vascular stenosis in MRA with a NATIVE sequence is improved by using the flow compensation technique. MRA with NATIVE sequence is considered to be a promising method for the evaluation of patients with severe renal dysfunction as a substitute for CT angiography or CE-MRA.
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Affiliation(s)
- Kengo Nakato
- Graduate School of Health Sciences, Kumamoto University
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Garcia-Carpintero ASM, Petcharunpaisan S, Ramalho JPRSNP, Castillo M. Advances in pediatric orbital magnetic resonance imaging. EXPERT REVIEW OF OPHTHALMOLOGY 2010. [DOI: 10.1586/eop.10.46] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Zhao Q, Lee S, Kent M, Schatzberg S, Platt S. Dynamic contrast-enhanced magnetic resonance imaging of canine brain tumors. Vet Radiol Ultrasound 2010; 51:122-9. [PMID: 20402394 DOI: 10.1111/j.1740-8261.2009.01635.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
We evaluated dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in canine brain tumors. Magnetic resonance data sets were collected on seven canine intracranial tumors with a 3 T magnet using a T1-weighted fast spin echo fluid attenuated inversion recovery sequence after an IV bolus injection (0.2 mmol/kg) of Gd-DTPA. The tumors were confirmed histopathologically as adenocarcinoma (n=1), ependymoma (n=1), meningioma (n=3), oligodendroglioma (n=1), and pituitary macroadenoma (n=1) The data were analyzed using a two-compartment pharmacokinetic model for estimation of three enhancement parameters, E(R) (rate of enhancement), Kel (rate of elimination), and Kep (rate constant), and a model-free phenomenologic parameter initial area under the Gd concentration curve (IAUGC) defined over the first 90s postenhancement. Pearson's correlations were calculated between parameters of the two methods. The IAUGC has a relatively strong association with the rate of enhancement E(R), with r ranges from 0.4 to 0.9, but it was weakly associated with Kep and Kel. To determine whether any two tumors differed significantly, the Kohnlmogorov-Smirnov test was used. The results showed that there were statistical differences (P < 0.05) between distributions of the enhancement pattern of each tumor. These kinetic parameters may characterize the perfusion and vascular permeability of the tumors and the IAUGC may reflect blood flow, vascular permeability, and the fraction of interstitial space. The kinetic parameters and the IAUGC derived from DCE-MRI present complementary information and they may be appropriate to noninvasively differentiate canine brain tumors although a larger prospective study is necessary.
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Affiliation(s)
- Qun Zhao
- Department of Physics & Astronomy, Biolmaging Research Center, University of Georgia, Athens, GA, USA.
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20
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7.0 Tesla MRI: the "field of dreams"? Acad Radiol 2010; 17:407-9. [PMID: 20207312 DOI: 10.1016/j.acra.2009.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2009] [Revised: 12/18/2009] [Accepted: 12/18/2009] [Indexed: 11/20/2022]
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21
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Seo HS. High field strength magnetic resonance imaging of brain lesion. JOURNAL OF THE KOREAN MEDICAL ASSOCIATION 2010. [DOI: 10.5124/jkma.2010.53.12.1086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Hyung Suk Seo
- Department of Radiology, Ansan Hospital, Korea University College of Medicine, Ansan, Korea
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22
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Lee SK. Clinical application of high field strength magnetic resonance imaging. JOURNAL OF THE KOREAN MEDICAL ASSOCIATION 2010. [DOI: 10.5124/jkma.2010.53.12.1054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Seung-Koo Lee
- Department of Radiology, Yonsei University College of Medicine, Seoul, Korea
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23
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Lövblad KO, Schaller K. Surgical anatomy and functional connectivity of the limbic system. Neurosurg Focus 2009; 27:E3. [PMID: 19645559 DOI: 10.3171/2009.5.focus09103] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
OBJECT The goal in this study was to highlight the potential of currently available imaging techniques for surgical planning of procedures in and around the limbic system. METHODS The authors review traditional and newer imaging techniques as applied to neurosurgical planning. Today MR imaging techniques play a preponderant role. The various applications of functional techniques such as diffusion weighted, diffusion tensor, perfusion, and functional MR imaging methods are discussed. RESULTS In addition to the high-resolution studies of anatomy that can be acquired, especially at higher field strengths (>or= 3 T), MR imaging now also offers the possibility of acquiring functional, metabolic, hemodynamic, and molecular information on normal and pathological brain processes. CONCLUSIONS The knowledge obtained using the various imaging techniques contributes substantially to understanding the disease processes in a way that drastically improves surgical planning.
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Affiliation(s)
- Karl-Olof Lövblad
- Department of Diagnostic and Interventional Neuroradiology, Geneva University Hospitals and Medical School, Geneva, Switzerland.
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Chavhan GB, Babyn PS, Singh M, Vidarsson L, Shroff M. MR Imaging at 3.0 T in Children: Technical Differences, Safety Issues, and Initial Experience. Radiographics 2009; 29:1451-66. [DOI: 10.1148/rg.295095041] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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25
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Mietchen D, Gaser C. Computational morphometry for detecting changes in brain structure due to development, aging, learning, disease and evolution. Front Neuroinform 2009; 3:25. [PMID: 19707517 PMCID: PMC2729663 DOI: 10.3389/neuro.11.025.2009] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Accepted: 07/09/2009] [Indexed: 01/14/2023] Open
Abstract
The brain, like any living tissue, is constantly changing in response to genetic and environmental cues and their interaction, leading to changes in brain function and structure, many of which are now in reach of neuroimaging techniques. Computational morphometry on the basis of Magnetic Resonance (MR) images has become the method of choice for studying macroscopic changes of brain structure across time scales. Thanks to computational advances and sophisticated study designs, both the minimal extent of change necessary for detection and, consequently, the minimal periods over which such changes can be detected have been reduced considerably during the last few years. On the other hand, the growing availability of MR images of more and more diverse brain populations also allows more detailed inferences about brain changes that occur over larger time scales, way beyond the duration of an average research project. On this basis, a whole range of issues concerning the structures and functions of the brain are now becoming addressable, thereby providing ample challenges and opportunities for further contributions from neuroinformatics to our understanding of the brain and how it changes over a lifetime and in the course of evolution.
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Affiliation(s)
- Daniel Mietchen
- Structural Brain Mapping Group, Department of Psychiatry, University of Jena D - 07743 Jena, Germany
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26
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Wattjes MP, Barkhof F. High field MRI in the diagnosis of multiple sclerosis: high field-high yield? Neuroradiology 2009; 51:279-92. [PMID: 19277621 DOI: 10.1007/s00234-009-0512-0] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2009] [Accepted: 02/11/2009] [Indexed: 10/21/2022]
Abstract
Following the approval of the U.S. Food and Drug Administration (FDA), high field magnetic resonance imaging (MRI) has been increasingly incorporated into the clinical setting. Especially in the field of neuroimaging, the number of high field MRI applications has been increased dramatically. Taking advantage on increased signal-to-noise ratio (SNR) and chemical shift, higher magnetic field strengths offer new perspectives particularly in brain imaging and also challenges in terms of several technical and physical consequences. Over the past few years, many applications of high field MRI in patients with suspected and definite multiple sclerosis (MS) have been reported including conventional and quantitative MRI methods. Conventional pulse sequences at 3 T offers higher lesion detection rates when compared to 1.5 T, particularly in anatomic regions which are important for the diagnosis of patients with MS. MR spectroscopy at 3 T is characterized by an improved spectral resolution due to increased chemical shift allowing a better quantification of metabolites. It detects significant axonal damage already in patients presenting with clinically isolated syndromes and can quantify metabolites of special interest such as glutamate which is technically difficult to quantify at lower field strengths. Furthermore, the higher susceptibility and SNR offer advantages in the field of functional MRI and diffusion tensor imaging. The recently introduced new generation of ultra-high field systems beyond 3 T allows scanning in submillimeter resolution and gives new insights into in vivo MS pathology on MRI. The objectives of this article are to review the current knowledge and level of evidence concerning the application of high field MRI in MS and to give some ideas of research perspectives in the future.
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Affiliation(s)
- Mike P Wattjes
- MS Center Amsterdam, Department of Radiology, VU University Medical Center, Amsterdam, The Netherlands.
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27
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Lee AG, Johnson MC, Policeni BA, Smoker WRK. Imaging for neuro-ophthalmic and orbital disease - a review. Clin Exp Ophthalmol 2008; 37:30-53. [PMID: 19016810 DOI: 10.1111/j.1442-9071.2008.01822.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
A literature review was performed by content experts in neuro-ophthalmology and neuroradiology using a systematic English-language Medline search (1994-2008) limited to articles with relevance to neuro-ophthalmic and orbital imaging. The information covered in this review includes: (i) the basic mechanics, indications and contraindications for cranial and orbital computed tomography and magnetic resonance (MR) imaging; (ii) the utility and indications for intravenous contrast, (iii) the use of specific MR sequences; (iv) the techniques and ophthalmic indications for computed tomography/MR angiography and venography; and (v) the techniques and indications for functional MR imaging, positron emission tomography scanning and single photon emission computed tomography. Throughout the review accurate and timely communication with the neuroradiologist regarding the clinical findings and suspected location of lesions is emphasized so as to optimize the ordering and interpretation of imaging studies for the ophthalmologist.
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Affiliation(s)
- Andrew G Lee
- Department of Ophthalmology, Universiyt of Iowa Hospitals and Clinics, Iowa City, Iowa 52242, USA.
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28
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Anzalone N, Scomazzoni F, Cirillo M, Righi C, Simionato F, Cadioli M, Iadanza A, Kirchin MA, Scotti G. Follow-up of coiled cerebral aneurysms at 3T: comparison of 3D time-of-flight MR angiography and contrast-enhanced MR angiography. AJNR Am J Neuroradiol 2008; 29:1530-6. [PMID: 18556359 DOI: 10.3174/ajnr.a1166] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Our aim was to compare contrast-enhanced MR angiography (CE-MRA) and 3D time-of-flight (TOF) MRA at 3T for follow-up of coiled cerebral aneurysms. MATERIALS AND METHODS Fifty-two patients treated with Guglielmi detachable coils for 54 cerebral aneurysms were evaluated at 3T MRA. 3D TOF MRA (TR/TE = 23/3.5; SENSE factor = 2.5) and CE-MRA by using a 3D ultrafast gradient-echo sequence (TR/TE = 5.9/1.8; SENSE factor = 3) enhanced with 0.1-mmol/kg gadobenate dimeglumine were performed in the same session. Source images, 3D maximum intensity projection, 3D shaded surface display, and/or 3D volume-rendered reconstructions were evaluated in terms of aneurysm occlusion/patency and artifact presence. RESULTS In terms of clinical classification, the 2 MRA sequences were equivalent for 53 of the 54 treated aneurysms: 21 were considered fully occluded, whereas 16 were considered to have a residual neck and 16 were considered residually patent at follow-up MRA. The remaining aneurysm appeared fully occluded at TOF MRA but had a residual patent neck at CE-MRA. Visualization of residual aneurysm patency was significantly (P = .001) better with CE-MRA compared with TOF MRA for 10 (31.3%) of the 32 treated aneurysms considered residually patent with both sequences. Coil artifacts were present in 5 cases at TOF MRA but in none at CE-MRA. No relationship was apparent between the visualization of patency and either the size of the aneurysm or the interval between embolization and follow-up. CONCLUSION At follow-up MRA at 3T, unenhanced TOF and CE-MRA sequences are similarly effective at classifying coiled aneurysms as occluded or residually patent. However, CE-MRA is superior to TOF MRA for visualization of residual patency and is associated with fewer artifacts.
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Affiliation(s)
- N Anzalone
- Department of Neuroradiology, Ospedale San Raffaele, Milan, Italy.
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Abstract
The principles of contrast mechanisms and fast pulse sequences underlying neurological and neuroradiological application of MRI are introduced in this part of a two-part review. In particular, the relaxation time constants T(1), T(2), and T(2) (*) are introduced, along with pulse sequences harnessing their contrast, spin-echo, fast spin echo (FSE), inversion recovery (IR), gradient recalled echo (GRE), and echo planar imaging (EPI). The use of gadolinium (Gd)-based contrast is discussed in both T(1)- and T(2) (*)-weighted sequences. Tradeoffs between speed and image quality are discussed, particularly in the context of long echo train sequences (FSE imaging and EPI). The influence of parallel imaging strategies is also discussed. T(2) (*) sensitivity is discussed as both a source of artifact as well as a contrast mechanism (perfusion imaging with contrast agents, susceptibility weighted imaging [SWI], and blood oxygenation level dependent [BOLD] imaging). Finally, the contrast mechanism of diffusion is introduced, as well as the concept of anisotropy. From these principles, the other part of this two-part review draws upon the pulse sequences and contrast mechanisms to design disease and indication-specific protocols for state-of-the-art clinical use.
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Affiliation(s)
- Timothy P L Roberts
- Department of Radiology, Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
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