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Carisch L, Lindt B, Richter H, Del Chicca F. Regional ADC values of the morphologically normal canine brain. Front Vet Sci 2023; 10:1219943. [PMID: 38026624 PMCID: PMC10663295 DOI: 10.3389/fvets.2023.1219943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 10/16/2023] [Indexed: 12/01/2023] Open
Abstract
Introduction Diffusion-weighted magnetic resonance imaging is increasingly available for investigation of canine brain diseases. Apparent diffusion coefficient (ADC) of normal canine brains is reported only in small numbers of subjects. The aim of the study was to investigate the ADC of different anatomical regions in the morphologically normal brain in a large population of canine patients in clinical setting. Additionally, possible influence on the ADC value of patient-related factors like sex, age and body weight, difference between the left and right side of the cerebral hemispheres, and between gray and white matter were investigated. Methods Brain magnetic resonance studies including diffusion-weighted images of dogs presented at the Vetsuisse Faculty-University Zurich between 2015 and 2020 were reviewed retrospectively. Only morphologically normal brain magnetic resonance studies of dogs presented with neurological signs or non-neurological signs were included. Apparent diffusion coefficient values of 12 regions of interest (ROIs) in each hemisphere and an additional region in the cerebellar vermis were examined in each dog. Results A total of 321 dogs (including 247 dogs with neurological signs and 62 dogs with non-neurological signs) of various breeds, sex and age were included. Apparent diffusion coefficient significantly varied among most anatomical brain regions. A significantly higher ADC was measured in the gray [median 0.79 (range 0.69-0.90) × 10-3 mm2/s] compared to the white matter [median 0.70 (range 0.63-0.85) × 10-3 mm2/s]. No significant differences were found between the left and right cerebral hemispheres in most of the regions, neither between sexes, different reproductive status, and not consistently between body weight groups. Age was correlated first with a decrease from dogs <1 year of age to middle-age (⩾3 to <8 years) dogs and later with an increase of ADC values in dogs ⩾8 years. Discussion Apparent diffusion coefficient values of 25 ROIs were described in 321 morphologically normal canine brains in clinical setting. Apparent diffusion coefficient differences depending on the brain anatomical region are present. Apparent diffusion coefficient differences among age classes are present, likely consistent with brain maturation and aging. The described data can be a reference for future studies in clinical settings on the canine brain.
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Affiliation(s)
- Lea Carisch
- Clinic for Diagnostic Imaging, Department of Diagnostics and Clinical Services, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
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Ramakrishnan D, von Reppert M, Krycia M, Sala M, Mueller S, Aneja S, Nabavizadeh A, Galldiks N, Lohmann P, Raji C, Ikuta I, Memon F, Weinberg BD, Aboian MS. Evolution and implementation of radiographic response criteria in neuro-oncology. Neurooncol Adv 2023; 5:vdad118. [PMID: 37860269 PMCID: PMC10584081 DOI: 10.1093/noajnl/vdad118] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2023] Open
Abstract
Radiographic response assessment in neuro-oncology is critical in clinical practice and trials. Conventional criteria, such as the MacDonald and response assessment in neuro-oncology (RANO) criteria, rely on bidimensional (2D) measurements of a single tumor cross-section. Although RANO criteria are established for response assessment in clinical trials, there is a critical need to address the complexity of brain tumor treatment response with multiple new approaches being proposed. These include volumetric analysis of tumor compartments, structured MRI reporting systems like the Brain Tumor Reporting and Data System, and standardized approaches to advanced imaging techniques to distinguish tumor response from treatment effects. In this review, we discuss the strengths and limitations of different neuro-oncology response criteria and summarize current research findings on the role of novel response methods in neuro-oncology clinical trials and practice.
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Affiliation(s)
- Divya Ramakrishnan
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut, USA
| | - Marc von Reppert
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut, USA
| | - Mark Krycia
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut, USA
| | - Matthew Sala
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut, USA
- Tulane University School of Medicine, New Orleans, Louisiana, USA
| | - Sabine Mueller
- Department of Neurology, Neurosurgery, and Pediatrics, University of California San Francisco, San Francisco, California, USA
| | - Sanjay Aneja
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut, USA
| | - Ali Nabavizadeh
- Department of Radiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Norbert Galldiks
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
- Institute of Neuroscience and Medicine (INM-3), Research Center Juelich, Juelich, Germany
- Center for Integrated Oncology (CIO), Universities of Aachen, Bonn, Cologne, and Duesseldorf, Cologne, Germany
| | - Philipp Lohmann
- Institute of Neuroscience and Medicine (INM-4), Research Center Juelich, Juelich, Germany
| | - Cyrus Raji
- Department of Radiology, Washington University in St. Louis School of Medicine, St. Louis, Missouri, USA
| | - Ichiro Ikuta
- Department of Radiology, Mayo Clinic, Phoenix, Arizona, USA
| | - Fatima Memon
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut, USA
| | - Brent D Weinberg
- Department of Radiology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Mariam S Aboian
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut, USA
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3
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Neuroradiology for ophthalmologists. Eye (Lond) 2020; 34:1027-1038. [DOI: 10.1038/s41433-019-0753-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 10/29/2019] [Accepted: 11/24/2019] [Indexed: 11/09/2022] Open
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Fouke SJ, Benzinger TL, Milchenko M, LaMontagne P, Shimony JS, Chicoine MR, Rich KM, Kim AH, Leuthardt EC, Keogh B, Marcus DS. The comprehensive neuro-oncology data repository (CONDR): a research infrastructure to develop and validate imaging biomarkers. Neurosurgery 2014; 74:88-98. [PMID: 24089052 DOI: 10.1227/neu.0000000000000201] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND Advanced imaging methods have the potential to serve as quantitative biomarkers in neuro-oncology research. However, a lack of standardization of image acquisition, processing, and analysis limits their application in clinical research. Standardization of these methods and an organized archival platform are required to better validate and apply these markers in research settings and, ultimately, in clinical practice. OBJECTIVE The primary objective of the Comprehensive Neuro-oncology Data Repository (CONDR) is to develop a data set for assessing and validating advanced imaging methods in patients diagnosed with brain tumors. As a secondary objective, informatics resources will be developed to facilitate the integrated collection, processing, and analysis of imaging, tissue, and clinical data in multicenter clinical trials. Finally, CONDR data and informatics resources will be shared with the research community for further analysis. METHODS CONDR will enroll 200 patients diagnosed with primary brain tumors. Clinical, imaging, and tissue-based data are obtained from patients serially, beginning with diagnosis and continuing over the course of their treatment. The CONDR imaging protocol includes structural and functional sequences, including diffusion- and perfusion-weighted imaging. All data are managed within an XNAT-based informatics platform. Imaging markers are assessed by correlating image and spatially aligned pathological markers and a variety of clinical markers. EXPECTED OUTCOMES CONDR will generate data for developing and validating imaging markers of primary brain tumors, including multispectral and probabilistic maps. DISCUSSION CONDR implements a novel, open-research model that will provide the research community with both open-access data and open-source informatics resources.
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Affiliation(s)
- Sarah Jost Fouke
- *Department of Neurological Surgery, Swedish Medical Center, Seattle, Washington; ‡Department of Radiology, Washington University School of Medicine, St. Louis, Missouri; §Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri; ‖Swedish Neuroscience Institute, Seattle, Washington, Radia PS, Everett, Washington
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Conti A, Raffa G, Granata F, Rizzo V, Germanò A, Tomasello F. Navigated Transcranial Magnetic Stimulation for “Somatotopic” Tractography of the Corticospinal Tract. Oper Neurosurg (Hagerstown) 2014; 10 Suppl 4:542-54; discussion 554. [DOI: 10.1227/neu.0000000000000502] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Abstract
BACKGROUND:
Diffusion tensor imaging tractography provides 3-dimensional reconstruction of principal white matter tracts, but its spatial accuracy has been questioned. Navigated transcranial magnetic stimulation (nTMS) enables somatotopic mapping of the motor cortex.
OBJECTIVE:
We used motor maps to reconstruct the corticospinal tract (CST) by integrating elements of its somatotopic organization. We analyzed the accuracy of this method compared with a standard technique and verified its reliability with intraoperative subcortical stimulation.
METHODS:
We prospectively collected data from patients who underwent surgery between January 2012 and October 2013 for lesions involving the CST. nTMS-based diffusion tensor imaging tractography was compared with a standard technique. The reliability and accuracy between the 2 techniques were analyzed by comparing the number of fibers, the concordance in size, and the location of the cortical end of the CST and the motor area. The accuracy of the technique was assessed by using direct subcortical stimulation.
RESULTS:
Twenty patients were enrolled in the study. nTMS-based tractography provided a detailed somatotopic reconstruction of the CST. This nTMS-based reconstruction resulted in a decreased number of fibers (305.1 ± 231.7 vs 1024 ± 193, P < .001) and a significantly greater overlap between the motor cortex and the cortical end-region of the CST compared with the standard technique (90.5 ± 8.8% vs 58.3 ± 16.6%, P < .001). Direct subcortical stimulation confirmed the CST location and the somatotopic reconstruction in all cases.
CONCLUSION:
These results suggest that nTMS-based tractography of the CST is more accurate and less operator dependent than the standard technique and provides a reliable anatomic and functional characterization of the motor pathway.
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Affiliation(s)
- Alfredo Conti
- Neurosurgical Clinic, Department of Neuroscience, and
| | | | - Francesca Granata
- Department of Radiological Sciences and Anatomy, University of Messina, Messina, Italy
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Ulrich NH, Ahmadli U, Woernle CM, Alzarhani YA, Bertalanffy H, Kollias SS. Diffusion tensor imaging for anatomical localization of cranial nerves and cranial nerve nuclei in pontine lesions: initial experiences with 3T-MRI. J Clin Neurosci 2014; 21:1924-7. [PMID: 24998855 DOI: 10.1016/j.jocn.2014.03.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Revised: 03/15/2014] [Accepted: 03/23/2014] [Indexed: 10/25/2022]
Abstract
With continuous refinement of neurosurgical techniques and higher resolution in neuroimaging, the management of pontine lesions is constantly improving. Among pontine structures with vital functions that are at risk of being damaged by surgical manipulation, cranial nerves (CN) and cranial nerve nuclei (CNN) such as CN V, VI, and VII are critical. Pre-operative localization of the intrapontine course of CN and CNN should be beneficial for surgical outcomes. Our objective was to accurately localize CN and CNN in patients with intra-axial lesions in the pons using diffusion tensor imaging (DTI) and estimate its input in surgical planning for avoiding unintended loss of their function during surgery. DTI of the pons obtained pre-operatively on a 3Tesla MR scanner was analyzed prospectively for the accurate localization of CN and CNN V, VI and VII in seven patients with intra-axial lesions in the pons. Anatomical sections in the pons were used to estimate abnormalities on color-coded fractional anisotropy maps. Imaging abnormalities were correlated with CN symptoms before and after surgery. The course of CN and the area of CNN were identified using DTI pre- and post-operatively. Clinical associations between post-operative improvements and the corresponding CN area of the pons were demonstrated. Our results suggest that pre- and post-operative DTI allows identification of key anatomical structures in the pons and enables estimation of their involvement by pathology. It may predict clinical outcome and help us to better understand the involvement of the intrinsic anatomy by pathological processes.
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Affiliation(s)
- Nils H Ulrich
- Department of Neurosurgery, University Hospital, University of Zurich, Zurich, Switzerland; Department of Neuroradiology, University Hospital, University of Zurich, Frauenklinikstrasse 10, 8091 Zurich, Switzerland.
| | - Uzeyir Ahmadli
- Department of Neuroradiology, University Hospital, University of Zurich, Frauenklinikstrasse 10, 8091 Zurich, Switzerland
| | - Christoph M Woernle
- Department of Neurosurgery, University Hospital, University of Zurich, Zurich, Switzerland
| | - Yahea A Alzarhani
- Department of Neuroradiology, University Hospital, University of Zurich, Frauenklinikstrasse 10, 8091 Zurich, Switzerland
| | | | - Spyros S Kollias
- Department of Neuroradiology, University Hospital, University of Zurich, Frauenklinikstrasse 10, 8091 Zurich, Switzerland
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Kotb SZ, Sultan AA, Elhawary GM, Taman SE. Value of diffusion weighted MRI in differentiating benign from malignant bony tumors and tumor like lesions. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2014. [DOI: 10.1016/j.ejrnm.2014.01.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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8
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Brainstem cavernoma surgery with the support of pre- and postoperative diffusion tensor imaging: initial experiences and clinical course of 23 patients. Neurosurg Rev 2014; 37:481-91; discussion 492. [DOI: 10.1007/s10143-014-0550-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2013] [Revised: 08/20/2013] [Accepted: 01/19/2014] [Indexed: 10/25/2022]
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Abstract
In the past three decades, there have been countless advances in imaging modalities that have revolutionized evaluation, management, and treatment of neuro-ophthalmic disorders. Non-invasive approaches for early detection and monitoring of treatments have decreased morbidity and mortality. Understanding of basic methods of imaging techniques and choice of imaging modalities in cases encountered in neuro-ophthalmology clinic is critical for proper evaluation of patients. Two main imaging modalities that are often used are computed tomography (CT) and magnetic resonance imaging (MRI). However, variations of these modalities and appropriate location of imaging must be considered in each clinical scenario. In this article, we review and summarize the best neuroimaging studies for specific neuro-ophthalmic indications and the diagnostic radiographic findings for important clinical entities.
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Affiliation(s)
- James D Kim
- Department of Ophthalmology (AGL: Clinical Professor), The University of Texas Medical Branch, Galveston, TX, USA
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11
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Boyer AC, Gonçalves LF, Lee W, Shetty A, Holman A, Yeo L, Romero R. Magnetic resonance diffusion-weighted imaging: reproducibility of regional apparent diffusion coefficients for the normal fetal brain. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2013; 41:190-7. [PMID: 22744761 PMCID: PMC3562408 DOI: 10.1002/uog.11219] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/30/2012] [Indexed: 05/15/2023]
Abstract
OBJECTIVE To evaluate the reproducibility of regional apparent diffusion coefficient (ADC) measurements of the normal fetal brain in the second and third trimesters of pregnancy. METHODS Fifty normal singleton fetuses from healthy pregnant women between 19 and 37 weeks' gestation were studied without sedation. Single-shot diffusion-weighted images of the fetal brain were obtained using a 1.5-Tesla magnetic resonance scanner and a six-channel body array coil. ADC maps were created using 0 and 1000 b-values along three orthogonal directions. Two examiners independently measured ADC values in the cerebellar hemispheres (CH), pons, thalamus, basal ganglia (BG), centrum semiovale (CSO), and frontal (FWM), parietal (PWM), temporal (TWM) and occipital (OWM) white matter. Correlation between ADC values and menstrual age was assessed by linear regression analysis. The bias and agreement of ADC measurements were determined using Bland-Altman plots. RESULTS ADC values either remained constant (BG, FWM, PWM, TWM, OWM, CSO) or decreased (CH, pons, thalamus) with advancing menstrual age. Mean intraobserver bias for ADC measurements was not significantly different from zero. Small interobserver differences in mean ADC measurements (i.e. a small mean bias) were detected for CH (1.26 ± 0.20 vs 1.20 ± 0.18 μm(2) /ms, P = 0.006), PWM (1.37 ± 0.29 vs 1.33 ± 0.26 μm(2) /ms, P = 0.02) and CSO (1.36 ± 0.29 vs 1.33 ± 0.28 μm(2) /ms, P < 0.0001). Measurement agreement was acceptable. CONCLUSIONS ADC measurements in normal unsedated fetuses in the second and third trimesters are reproducible except for small differences for PWM, CH and CSO between examiners.
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Affiliation(s)
- A C Boyer
- Department of Diagnostic Radiology, Oakland University William Beaumont School of Medicine, Rochester, MI 48073, USA.
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12
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Abou Zeid N, Pirko I, Erickson B, Weigand SD, Thomsen KM, Scheithauer B, Parisi JE, Giannini C, Linbo L, Lucchinetti CF. Diffusion-weighted imaging characteristics of biopsy-proven demyelinating brain lesions. Neurology 2012; 78:1655-62. [PMID: 22573639 DOI: 10.1212/wnl.0b013e3182574f66] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
OBJECTIVES To describe lesional diffusion-weighted imaging characteristics in a cohort of patients with biopsy-proven CNS inflammatory demyelinating disease (IDD) and compare diffusion characteristics of ring-enhancing CNS IDD lesions vs abscesses and tumors. METHODS Forty prebiopsy apparent diffusion coefficient (ADC) maps were reviewed from 30 patients with CNS IDD. Lesions were analyzed for size, T2-weighted (T2W) hypointense rim, enhancement, and ADC pattern. ADC patterns of CNS IDD ring-enhancing lesions were compared with a published cohort of 35 patients with ring-enhancing tumors and abscesses. RESULTS IDD lesions displayed a spectrum of peripheral ADC patterns at the lesion edge: restricted diffusion (low ADC), 33%; increased diffusion (high ADC), 60%; and normal diffusion (homogeneously isointense), 7%. Of biopsied lesions, 93% enhanced (ring, 52%; heterogeneous, 34%; homogeneous, 7%). A hypointense T2W rim was observed in 53%. A ring pattern on ADC (isointense or dark) was associated with T2W hypointense rims (p = 0.02) but not with ring enhancement. On serial imaging, 4 of 7 (57%) patients demonstrated changes in ADC patterns. Peripheral restriction was more common in IDD (p = 0.006) than in tumors or abscesses, whereas central restriction was only observed in abscesses. Restricted lesions in the same stage were more common in the non-IDD cohort (42% vs 20%), with a uniform restricted pattern seen only in abscesses. CONCLUSIONS In ring-enhancing lesions, peripheral diffusion restriction is more common in IDD than in tumors/abscesses, whereas central restriction is more common among abscesses. Rapid ADC pattern changes in IDD probably reflect dynamic lesion evolution and may distinguish IDD from tumors.
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Affiliation(s)
- N Abou Zeid
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
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El-Badrawy A, Elzaafarany M, Youssef TF, El-Badrawy MK. Role of diffusion-weighted MR imaging in chest wall masses. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2011. [DOI: 10.1016/j.ejrnm.2011.06.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
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Hygino da Cruz LC, Vieira IG, Domingues RC. Diffusion MR Imaging: An Important Tool in the Assessment of Brain Tumors. Neuroimaging Clin N Am 2011; 21:27-49, vii. [DOI: 10.1016/j.nic.2011.01.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Zhou XJ, Gao Q, Abdullah O, Magin RL. Studies of anomalous diffusion in the human brain using fractional order calculus. Magn Reson Med 2010; 63:562-9. [PMID: 20187164 DOI: 10.1002/mrm.22285] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
It is well known that diffusion-induced MR signal loss deviates from monoexponential decay, particularly at high b-values (e.g., >1500 sec/mm(2) for human brain tissues). A number of models have been developed to describe this anomalous diffusion behavior and relate the diffusion measurements to tissue structures. Recently, a new diffusion model was proposed by solving the Bloch-Torrey equation using fractional order calculus with respect to time and space (Magin et al., J Magn Reson 2008;190:255-270; Zhou et al., Proc Int'l Soc Magn Reson Med 2008). Using a spatial Laplacian [symbol: see text], this model yields a new set of parameters to describe anomalous diffusion: diffusion coefficient D, fractional order derivative in space beta, and a spatial parameter mu (in units of microm). In this study, we demonstrate that the fractional calculus model can be successfully applied to analyzing diffusion images of healthy human brain tissues in vivo. Five human volunteers were scanned on a commercial 3-T scanner using a customized single-shot echo-planar imaging diffusion sequence with 15 b values ranging from 0 to 4700 sec/mm(2). The set of images was analyzed using the fractional calculus model, producing spatially resolved maps of D, beta, and mu. The beta and mu maps showed notable contrast between white and gray matter. The contrast has been attributed to the varying degree of complexity of the underlying tissue structures and microenvironment. Although the biophysical basis of beta and mu remains elusive, the potential utility of these parameters to characterize the environment for molecular diffusion, as a complement to apparent diffusion coefficient, may lead to a new way to investigate tissue structural changes in disease progression, intervention, and regression.
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Affiliation(s)
- Xiaohong Joe Zhou
- Department of Radiology, University of Illinois Medical Center, Chicago, Illinois 60612, USA.
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Cauley KA, Andrews T, Gonyea JV, Filippi CG. Magnetic resonance diffusion tensor imaging and tractography of intracranial cavernous malformations: preliminary observations and characterization of the hemosiderin rim. J Neurosurg 2010; 112:814-23. [PMID: 20367384 DOI: 10.3171/2009.8.jns09586] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Cavernous malformations (CMs) can cause symptoms that appear out of proportion to the lesion size, leading one to hypothesize that they may have an effect on adjacent white matter that is not fully explained by local mass effect. The goal of this study was to investigate the diffusion tensor (DT) properties of CMs, the hemosiderin rim, and normal-appearing adjacent white matter. METHODS Eighteen cavernous malformations were characterized using standard MR imaging sequences as well as 6-direction DT imaging with single-shot echo planar-gradient echo imaging at 3 tesla. RESULTS Diffusion tensor imaging demonstrated that CMs have a characteristic signature on DT imaging, with low fractional anisotropy (FA) and high mean diffusivity centrally within the lesion. The hemosiderin rim had a high FA value relative to the central lesion or adjacent white matter. Tractography revealed that tracts neatly deviate around CMs. Tracts were typically seen to pass through the hemosiderin rim. CONCLUSIONS The hemosiderin rim of CMs was intimately associated with white matter tracts that were deviated by the central lesion. These findings are consistent with histopathological reports that the hemosiderin rim is composed of blood breakdown products deposited in viable white matter.
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Affiliation(s)
- Keith A Cauley
- Department of Radiology, Division of Neuroradiology, University of Massachusetts Medical Center, Worcester, Massachusetts 01655, USA.
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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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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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Huang MQ, Pickup S, Nelson DS, Qiao H, Xu HN, Li LZ, Zhou R, Delikatny EJ, Poptani H, Glickson JD. Monitoring response to chemotherapy of non-Hodgkin's lymphoma xenografts by T(2)-weighted and diffusion-weighted MRI. NMR IN BIOMEDICINE 2008; 21:1021-1029. [PMID: 18988250 PMCID: PMC6594105 DOI: 10.1002/nbm.1261] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
An effective method for in vivo detection of early therapeutic response of patients with non-Hodgkin's lymphoma would enable personalized clinical management of cancer therapy and facilitate the design of optimal treatment regimens. This study evaluates the feasibility of T(2)-weighted MRI (T2WI) and diffusion-weighted MRI (DWI) for in vivo detection of response of human diffuse large B-cell lymphoma xenografts in severe combined immunodeficient mice to chemotherapy. Each cycle of combination chemotherapy with cyclophosphamide, hydroxydoxorubicin, Oncovin, prednisone, and bryostatin 1 (CHOPB) was administered to tumor-carrying mice weekly for up to four cycles. T2WI and DWI were performed before the initiation of CHOPB and after each cycle of CHOPB. In order to corroborate the MRI results, histological analyses were carried out on control tumors and treated tumors after completion of all MRI studies. DWI revealed a significant (P < 0.03) increase in the mean apparent diffusion coefficient in CHOPB-treated tumors as early as 1 week after initiation of CHOPB. However, a significant (P < 0.03) decrease in mean T(2) was observed only after two cycles of CHOPB. Both MRI methods produced high-resolution (0.1 x 0.1 x 1.0 mm(3)) maps of regional therapeutic response in the treated tumors based on local apparent diffusion coefficient and T(2). Only a specific region of the tumors (in 3 of the 5 tumors) corresponding to about one third of the tumor volume exhibited a response-associate increase in ADC and decrease in T(2). An adjacent region exhibited an increase in T(2) and no change in ADC. The rest of the tumor was indistinguishable from sham-treated controls by MRI criteria. The therapeutic response of the treated tumors detected by MRI was accompanied by changes in tumor cell density, proliferation and apoptosis revealed by histological studies performed upon completion of the longitudinal study. The mechanism producing the regional response of the tumor remains to be elucidated.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Jerry D. Glickson
- Correspondence to: J. D.
Glickson, Department of Radiology, University of Pennsylvania, Philadelphia, PA
19104, USA.
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20
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Klein J, Laun F, Erhard P, Diehl V, Hahn HK. On the Reliability of Quantitative Volumetric and Structural Neuroimaging. ACTA ACUST UNITED AC 2008. [DOI: 10.1111/j.1617-0830.2009.00128.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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21
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Obenaus A, Ashwal S. Magnetic resonance imaging in cerebral ischemia: focus on neonates. Neuropharmacology 2008; 55:271-80. [PMID: 18601935 DOI: 10.1016/j.neuropharm.2008.06.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2007] [Revised: 05/30/2008] [Accepted: 06/02/2008] [Indexed: 10/21/2022]
Abstract
Magnetic resonance imaging (MRI) has dramatically changed our ability to diagnose and treat stroke as well as follow its evolution and response to treatment. Early stroke and ischemia can be visualized using diffusion-weighted imaging (DWI), which utilizes proton diffusion within tissues as a reporter for evolving neuropathology that reflects cytotoxic edema, particularly during the first several days after injury. Historically, T2-weighted imaging (T2WI) has been used for evaluation of vasogenic edema and also is a reliable indicator of injured tissue late after injury. While visual analysis of MR data can provide information about the evolution of injury, quantitative analyses allow definitive and objective evaluations of injury size and location and the effectiveness of novel therapeutic strategies. We review the clinical basis of imaging for stroke and ischemia diagnosis and the methods for post-processing of MR data that could provide novel insights into the evolution and pathophysiology of stroke in the newborn.
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Affiliation(s)
- Andre Obenaus
- Department of Radiation Medicine, Loma Linda University, Loma Linda, CA 92354, USA.
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22
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Chen X, Weigel D, Ganslandt O, Fahlbusch R, Buchfelder M, Nimsky C. Diffusion tensor-based fiber tracking and intraoperative neuronavigation for the resection of a brainstem cavernous angioma. ACTA ACUST UNITED AC 2007; 68:285-91; discussion 291. [PMID: 17719968 DOI: 10.1016/j.surneu.2007.05.005] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2007] [Accepted: 05/09/2007] [Indexed: 11/25/2022]
Abstract
BACKGROUND Surgical treatment of brainstem cavernous angioma involving eloquent fiber tracts is one of the most challenging areas of contemporary neurosurgery. Diffusion tensor imaging-based fiber tracking adds essential information for preoperative planning in neurosurgical practice. Integration of the tractography into neuronavigation system makes it possible for the intraoperative visualization of the major fiber tracts. It may help increase the likelihood of the total resection of tumors adjacent to the eloquent fiber tracts and avoid new neurologic deficits after surgery. CASE DESCRIPTION We report our valuable experience of such integration for the resection of a deeply located brainstem cavernous angioma. CONCLUSION Inclusion of tractography in standard imaging protocols for neuronavigation systems can provide important information regarding neural tracts for the planning of brainstem surgery. It can also increase the safety of neurosurgical intervention near white matter tracts in the brainstem.
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Affiliation(s)
- Xiaolei Chen
- Department of Neurosurgery, University of Erlangen-Nürnberg, 91054 Erlangen, Germany.
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23
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Obenaus A, Jacobs RE. Magnetic Resonance Imaging of Functional Anatomy: Use for Small Animal Epilepsy Models. Epilepsia 2007; 48 Suppl 4:11-7. [PMID: 17767571 DOI: 10.1111/j.1528-1167.2007.01237.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Neuroimaging has greatly assisted the diagnosis and treatment of epilepsy. Volumetric analysis, diffusion-weighted imaging, and other magnetic resonance imaging (MRI) modalities provide a clear picture of altered anatomical structures in both focal and nonfocal disease. More recently, advances in novel imaging methodologies have provided unique insights into this disease. Two examples include manganese-enhanced MRI (MEMRI) and diffusion tensor imaging (DTI). MEMRI involves injection of MnCl(2) to evaluate neuronal activity where it is actively transported. Areas of neuronal hyperactivity are expected to have altered uptake and transport. Mapping of activation along preferential uptake pathways can be confirmed by T(1)-weighted imaging. DTI uses the intrinsic preferential mobility of water movement along axonal pathways to map anatomical regions. DTI has been used to investigate white matter disease and is now being applied to clinical and, to a lesser extent, animal investigations of seizure disorders. These two diverse MRI methods can be applied to animal models to provide important information about the functional status of anatomical regions that may be altered by epilepsy.
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Affiliation(s)
- Andre Obenaus
- Non-Invasive Imaging Laboratory, Radiation Medicine Department, Loma Linda University, Loma Linda, California 92354, USA.
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24
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Abstract
Stroke is a devastating disease with a complex pathophysiology. It is a major cause of death and disability in North America. To fully characterize its extent and effects, one requires numerous specialized anatomical and functional MR techniques, specifically diffusion-weighted imaging, MR angiography, and perfusion-weighted imaging. The advent of 3.0 T clinical scanners has the potential to provide higher quality information in potentially less time compared with 1.5 T stroke-specific MR imaging protocols. This article gives a brief overview of stroke, presents the principles and clinical applications of the relevant MR techniques required for diagnostic stroke imaging at high field, and discusses the advantages, challenges, and limitations of 3.0 T imaging as they relate to stroke.
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25
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Cruz LCH, Sorensen AG. Diffusion Tensor Magnetic Resonance Imaging of Brain Tumors. Magn Reson Imaging Clin N Am 2006; 14:183-202. [PMID: 16873010 DOI: 10.1016/j.mric.2006.06.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
DTI seems to offer the possibility of adding important information to presurgical planning. Although experience is limited, DTI seems to provide useful local information about the structures near the tumor, and this seems to be useful in planning. In the future, DTI may provide an improved way to monitor intraoperative surgical procedures as well as their complications. Furthermore, evaluation of the response to treatment with chemotherapy and radiation therapy might also be possible. Although DTI has some limitations, its active investigation and further study are clearly warranted.
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Affiliation(s)
- L Celso Hygino Cruz
- Clínica de Diagnóstico por Imagem, Multi-Imagem Ressonância Magnética, Av. das Ameréricas 4666, Centro Médico Barrashopping, Rio de Janeiro, Brazil
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26
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Hlatky R, Jackson EF, Weinberg JS, McCutcheon IE. intraoperative neuronavigation using diffusion tensor MR tractography for the resection of a deep tumor adjacent to the corticospinal tract. Stereotact Funct Neurosurg 2006; 83:228-32. [PMID: 16534255 DOI: 10.1159/000091954] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVE AND IMPORTANCE Delineation of cerebral white matter tracts using MR tractography adds essential information for planning intracranial surgery. Integrating tractography with intraoperative neuronavigation may reduce the likelihood of new neurological deficits after surgery done to remove tumors adjacent to the projection fibers of eloquent cortex. We report the utility of such integration for the resection of deep (paraventricular) tumors. CLINICAL PRESENTATION A 67-year-old male with malignant melanoma underwent stereotactic radiosurgery for a single metastasis within the paraventricular white matter of the right frontal lobe near the corticospinal tract. The lesion doubled in size within 12 months of radiotherapy. Surgical extirpation was performed aided by intraoperative neuronavigation. TECHNIQUE MR images of the brain including MR tractography and post-contrast T1-weighted sequences were acquired and imported into a neuronavigational workstation. Asymmetric fusion of contrast-enhanced images and tractography was employed to assist in preservation of the integrity of critical white matter tracts during the surgical procedure. CONCLUSION Inclusion of tractography in standard imaging protocols for neuronavigational systems may increase the safety of neurosurgical intervention near white matter tracts, including deep areas adjacent to the ventricles.
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Affiliation(s)
- Roman Hlatky
- Department of Neurosurgery, University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA.
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27
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Olsen KI, Schroeder P, Corby R, Vucic I, Bardo DME. Advanced magnetic resonance imaging techniques to evaluate CNS glioma. Expert Rev Neurother 2005; 5:S3-11. [PMID: 16274265 DOI: 10.1586/14737175.5.6.s3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
To make full use of the benefits of magnetic resonance imaging (MRI) in the evaluation of intracranial glioma, a variety of advanced MRI and qualitative and quantitative techniques can be added to the radiologists' diagnostic armamentarium, beyond the standard contrast-enhanced images. These techniques include perfusion MRI, which is useful in the characterization of glioma because a relative quantification of cerebral microcirculatory parameters may be estimated; magnetic resonance spectroscopy, which can provide an estimate of the concentration of normal and abnormal metabolites in the brain and, when supplemented with magnetic resonance perfusion data, can be a useful tool for distinguishing between tumor recurrence and radiation necrosis; and diffusion tensor imaging, which combines physiologic behaviors unique to the cytoarchitecture of brain cells and the interstitial tissues with 2D and 3D anatomic magnetic resonance images, and thereby differentiates intact white matter tracts, displaced by tumor or surrounding edema, from invasion or disruption by a more aggressive neoplasm.
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Affiliation(s)
- Kristina I Olsen
- Department of Neuroradiology, The University of Chicago, 5841 S. Maryland Ave., MC 2026, Chicago, IL 60637, USA.
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28
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Abstract
DTI seems to offer the possibility of adding important information to presurgical planning. Although experience is limited, DTI seems to provide useful local information about the structures near the tumor, and this seems to be useful in planning. In the future, DTI may provide an improved way to monitor intraoperative surgical procedures as well as their complications. Furthermore, evaluation of the response to treatment with chemotherapy and radiation therapy might also be possible. Although DTI has some limitations, its active investigation and further study are clearly warranted.
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Affiliation(s)
- L Celso Hygino Cruz Júnior
- Clínica de Diagnóstico por Imagem, Multi-Imagem Ressonância Magnética, Av. das Ameréricas 4666, Centro Médico Barrashopping, Rio de Janeiro, Brazil
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29
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Yousem DM. Invited Commentary • Authors' Response. Radiographics 2005. [DOI: 10.1148/rg.251045181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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30
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Wilms G, Demaerel P, Sunaert S. Intra-axial brain tumours. Eur Radiol 2004; 15:468-84. [PMID: 15627192 DOI: 10.1007/s00330-004-2555-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2004] [Revised: 10/11/2004] [Accepted: 10/14/2004] [Indexed: 10/26/2022]
Abstract
The radiological diagnosis and differential diagnosis of intra-axial tumours no longer relies on CT scan and routine MR sequences alone. Standard multiplanar imaging has to be combined with fMRI to allow the exact anatomic location of the lesion and precise determination of the extension of the tumour. Perfusion and diffusion MR is becoming more and more important in the differential diagnosis of cerebral mass lesions and in the grading and typing of gliomas. More sophisticated techniques such as diffusion tensor imaging and spectroscopy will further enhance the value of the radiological studies.
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Affiliation(s)
- G Wilms
- Department of Radiology, U.Z. Gasthuisberg, Herestraat 49, 3000, Leuven, Belgium.
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31
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Lee AG, Brazis PW, Garrity JA, White M. Imaging for neuro-ophthalmic and orbital disease. Am J Ophthalmol 2004; 138:852-62. [PMID: 15531324 DOI: 10.1016/j.ajo.2004.06.069] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/17/2004] [Indexed: 10/26/2022]
Abstract
PURPOSE To provide an update on imaging of the brain and orbit for ophthalmologists. DESIGN Literature review. METHODS A systematic English-language medline search and summary of recent literature on imaging of brain and orbit was performed. RESULTS Computed tomography and magnetic resonance (MR) scanning are the mainstays for the evaluation of most disorders involving the brain and orbit. Computed tomography angiography and magnetic resonance angiography are relatively newer applications that are useful for the evaluation of arterial and venous disorders. Special sequences such as fat suppression and fluid attenuation inversion recovery are useful techniques for specific ophthalmic indications. Diffusion weighted imaging and perfusion-weighted imaging are improving the evaluation of acute stroke. Functional MRI, positron emission tomography scanning and single photon emission computed tomography may provide useful information regarding brain or tumor metabolism. Magnetic resonance spectroscopy has expanded our knowledge of brain function. Newer imaging studies have improved our diagnostic abilities on many fronts, including new sequences, new applications of imaging studies, and functional imaging of brain. CONCLUSION New imaging techniques for brain and orbit have an increased potential for improving diagnostic yield. Accurate and timely communication with the neuroradiologist can optimize the prescription and interpretation of imaging in ophthalmology.
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Affiliation(s)
- Andrew G Lee
- Department of Ophthalmology, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA.
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