1
|
Kuo DP, Chen YC, Cheng SJ, Hsieh KLC, Ou CY, Li YT, Chen CY. Ischemia-reperfusion injury in a salvaged penumbra: Longitudinal high-tesla perfusion magnetic resonance imaging in a rat model. Magn Reson Imaging 2024; 112:47-53. [PMID: 38909765 DOI: 10.1016/j.mri.2024.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Revised: 05/23/2024] [Accepted: 06/20/2024] [Indexed: 06/25/2024]
Abstract
INTRODUCTION Although ischemia-reperfusion (I/R) injury varies between cortical and subcortical regions, its effects on specific regions remain unclear. In this study, we used various magnetic resonance imaging (MRI) techniques to examine the spatiotemporal dynamics of I/R injury within the salvaged ischemic penumbra (IP) and reperfused ischemic core (IC) of a rodent model, with the aim of enhancing therapeutic strategies by elucidating these dynamics. MATERIALS AND METHODS A total of 17 Sprague-Dawley rats were subjected to 1 h of transient middle cerebral artery occlusion with a suture model. MRI, including diffusion tensor imaging (DTI), T2-weighted imaging, perfusion-weighted imaging, and T1 mapping, was conducted at multiple time points for up to 5 days during the I/R phases. The spatiotemporal dynamics of blood-brain barrier (BBB) modifications were characterized through changes in T1 within the IP and IC regions and compared with mean diffusivity (MD), T2, and cerebral blood flow. RESULTS During the I/R phases, the MD of the IC initially decreased, normalized after recanalization, decreased again at 24 h, and peaked on day 5. By contrast, the IP remained relatively stable. Both the IP and IC exhibited hyperperfusion, with the IP reaching its peak at 24 h, followed by resolution, whereas hyperperfusion was maintained in the IC until day 5. Despite hyperperfusion, the IP maintained an intact BBB, whereas the IC experienced persistent BBB leakage. At 24 h, the IC exhibited an increase in the T2 signal, corresponding to regions exhibiting BBB disruption at 5 days. CONCLUSIONS Hyperperfusion and BBB impairment have distinct patterns in the IP and IC. Quantitative T1 mapping may serve as a supplementary tool for the early detection of malignant hyperemia accompanied by BBB leakage, aiding in precise interventions after recanalization. These findings underscore the value of MRI markers in monitoring ischemia-specific regions and customizing therapeutic strategies to improve patient outcomes.
Collapse
Affiliation(s)
- Duen-Pang Kuo
- Department of Medical Imaging, Taipei Medical University Hospital, Taipei, Taiwan; Translational Imaging Research Center, Taipei Medical University Hospital, Taipei, Taiwan; Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Yung-Chieh Chen
- Department of Medical Imaging, Taipei Medical University Hospital, Taipei, Taiwan; Translational Imaging Research Center, Taipei Medical University Hospital, Taipei, Taiwan; Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Sho-Jen Cheng
- Department of Medical Imaging, Taipei Medical University Hospital, Taipei, Taiwan; Translational Imaging Research Center, Taipei Medical University Hospital, Taipei, Taiwan
| | - Kevin Li-Chun Hsieh
- Department of Medical Imaging, Taipei Medical University Hospital, Taipei, Taiwan; Translational Imaging Research Center, Taipei Medical University Hospital, Taipei, Taiwan; Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Chen-Yin Ou
- Translational Imaging Research Center, Taipei Medical University Hospital, Taipei, Taiwan
| | - Yi-Tien Li
- Translational Imaging Research Center, Taipei Medical University Hospital, Taipei, Taiwan; Research Center for Neuroscience, Taipei Medical University, Taipei, Taiwan; Ph.D. Program in Medical Neuroscience, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan.
| | - Cheng-Yu Chen
- Department of Medical Imaging, Taipei Medical University Hospital, Taipei, Taiwan; Translational Imaging Research Center, Taipei Medical University Hospital, Taipei, Taiwan; Research Center for Artificial Intelligence in Medicine, Taipei Medical University, Taipei, Taiwan; Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Department of Radiology, National Defense Medical Center, Taipei, Taiwan
| |
Collapse
|
2
|
Boudreau E, Kerwin SC, DuPont EB, Levine JM, Griffin JF. Temporal and sequence-related variability in diffusion-weighted imaging of presumed cerebrovascular accidents in the dog brain. Front Vet Sci 2022; 9:1008447. [PMID: 36419725 PMCID: PMC9676236 DOI: 10.3389/fvets.2022.1008447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 10/20/2022] [Indexed: 11/09/2022] Open
Abstract
Diffusion-weighted MRI (DWI) is often used to guide clinical interpretation of intraparenchymal brain lesions when there is suspicion for a cerebrovascular accident (CVA). Despite widespread evidence that imaging and patient parameters can influence diffusion-weighted measurements, such as apparent diffusion coefficient (ADC), there is little published data on such measurements for naturally occurring CVA in clinical cases in dogs. We describe a series of 22 presumed and confirmed spontaneous canine CVA with known time of clinical onset imaged on a single 3T magnet between 2011 and 2021. Median ADC values of < 1.0x10−3 mm2/s were seen in normal control tissues as well as within CVAs. Absolute and relative ADC values in CVAs were well-correlated (R2 = 0.82). Absolute ADC values < 1.0x10−3 mm2/s prevailed within ischemic CVAs, though there were exceptions, including some lesions of < 5 days age. Some lesions showed reduced absolute but not relative ADC values when compared to matched normal contralateral tissue. CVAs with large hemorrhagic components did not show restricted diffusion. Variation in the DWI sequence used impacted the ADC values obtained. Failure to identify a region of ADC < 1.0x10−3 mm2/s should not exclude CVA from the differential list when clinical suspicion is high.
Collapse
Affiliation(s)
- Elizabeth Boudreau
- Department of Small Animal Clinical Sciences, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States
- *Correspondence: Elizabeth Boudreau
| | - Sharon C. Kerwin
- Department of Small Animal Clinical Sciences, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States
| | - Emily B. DuPont
- Department of Small Animal Clinical Sciences, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States
| | - Jonathan M. Levine
- Department of Small Animal Clinical Sciences, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States
| | - John F. Griffin
- Department of Large Animal Clinical Sciences, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States
| |
Collapse
|
3
|
Moon BF, Iyer SK, Josselyn NJ, Hwuang E, Swago S, Keeney SJ, Castillero E, Ferrari G, Pilla JJ, Gorman JH, Gorman RC, Tschabrunn C, Shou H, Matthai W, Wehrli FW, Ferrari VA, Han Y, Litt H, Witschey WR. Magnetic susceptibility and R2* of myocardial reperfusion injury at 3T and 7T. Magn Reson Med 2022; 87:323-336. [PMID: 34355815 PMCID: PMC9067599 DOI: 10.1002/mrm.28955] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/15/2021] [Accepted: 07/17/2021] [Indexed: 01/03/2023]
Abstract
PURPOSE Magnetic susceptibility (Δχ) alterations have shown association with myocardial infarction (MI) iron deposition, yet there remains limited understanding of the relationship between relaxation rates and susceptibility or the effect of magnetic field strength. Hence, Δχ and R 2 ∗ in MI were compared at 3T and 7T. METHODS Subacute MI was induced by coronary artery ligation in male Yorkshire swine. 3D multiecho gradient echo imaging was performed at 1-week postinfarction at 3T and 7T. Quantitative susceptibility mapping images were reconstructed using a morphology-enabled dipole inversion. R 2 ∗ maps and quantitative susceptibility mapping were generated to assess the relationship between R 2 ∗ , Δχ, and field strength. Infarct histopathology was investigated. RESULTS Magnetic susceptibility was not significantly different across field strengths (7T: 126.8 ± 41.7 ppb; 3T: 110.2 ± 21.0 ppb, P = NS), unlike R 2 ∗ (7T: 247.0 ± 14.8 Hz; 3T: 106.1 ± 6.5 Hz, P < .001). Additionally, infarct Δχ and R 2 ∗ were significantly higher than remote myocardium. Magnetic susceptibility at 7T versus 3T had a significant association (β = 1.02, R2 = 0.82, P < .001), as did R 2 ∗ (β = 2.35, R2 = 0.98, P < .001). Infarct pathophysiology and iron deposition were detected through histology and compared with imaging findings. CONCLUSION R 2 ∗ showed dependence and Δχ showed independence of field strength. Histology validated the presence of iron and supported imaging findings.
Collapse
Affiliation(s)
- Brianna F. Moon
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Srikant Kamesh Iyer
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Nicholas J. Josselyn
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Eileen Hwuang
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Sophia Swago
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Samuel J. Keeney
- Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Pediatrics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Estibaliz Castillero
- Department of Surgery, Columbia University Irving Medical Center, New York City, NY, USA
| | - Giovanni Ferrari
- Department of Surgery, Columbia University Irving Medical Center, New York City, NY, USA
| | - James J. Pilla
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Joseph H. Gorman
- Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Robert C. Gorman
- Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Cory Tschabrunn
- Department of Medicine, Division of Cardiovascular Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Haochang Shou
- Department of Biostatistics, Epidemiology and Informatics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - William Matthai
- Department of Medicine, Penn Presbyterian Medical Center, University of Pennsylvania, Philadelphia, PA, USA
| | - Felix W. Wehrli
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Victor A. Ferrari
- Department of Medicine, Division of Cardiovascular Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yuchi Han
- Department of Medicine, Division of Cardiovascular Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Harold Litt
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Medicine, Division of Cardiovascular Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Walter R. Witschey
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| |
Collapse
|
4
|
Regenhardt RW, Bretzner M, Zanon Zotin MC, Bonkhoff AK, Etherton MR, Hong S, Das AS, Alotaibi NM, Vranic JE, Dmytriw AA, Stapleton CJ, Patel AB, Kuchcinski G, Rost NS, Leslie-Mazwi TM. Radiomic signature of DWI-FLAIR mismatch in large vessel occlusion stroke. J Neuroimaging 2022; 32:63-67. [PMID: 34506667 PMCID: PMC8752494 DOI: 10.1111/jon.12928] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 08/02/2021] [Accepted: 08/19/2021] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND AND PURPOSE Ischemic diffusion-weighted imaging-fluid-attenuated inversion recovery (DWI-FLAIR) mismatch may be useful in guiding acute stroke treatment decisions given its relationship to onset time and parenchymal viability; however, it relies on subjective grading. Radiomics is an emerging image quantification methodology that may objectively represent continuous image characteristics. We propose a novel radiomics approach to characterize DWI-FLAIR mismatch. METHODS Ischemic lesions were visually graded for FLAIR positivity (absent, subtle, obvious) among consecutive large vessel occlusion stroke patients who underwent hyperacute MRI. Radiomic features were extracted from within the lesions on DWI and FLAIR. The DWI-FLAIR mismatch radiomics signature was built with features systematically selected by a cross-validated ElasticNet linear regression model of mismatch. RESULTS We identified 103 patients with mean age 68 ± 16 years; 63% were female. FLAIR hyperintensity was absent in 25%, subtle in 55%, and obvious in 20%. Inter-rater agreement for visual grading was moderate (Κ = .58). The radiomics signature of DWI-FLAIR mismatch included native FLAIR histogram kurtosis and local binary pattern-filtered FLAIR gray-level cluster shade; both correlated with visual grading (ρ = -.42, p < .001 and ρ = .40, p < .001, respectively). CONCLUSIONS Radiomics can describe DWI-FLAIR mismatch and may provide objective, continuous biomarkers for infarct evolution using clinical-grade images. These novel biomarkers may prove useful for treatment decisions and future research.
Collapse
Affiliation(s)
- Robert W. Regenhardt
- Neurosurgery, Massachusetts General Hospital, Boston, USA,Neurology, Massachusetts General Hospital, Boston, USA,Corresponding Author Robert W. Regenhardt, 55 Fruit St, WACC 720, Boston, MA, Telephone 617-724-2951, Fax 877-992-9812,
| | - Martin Bretzner
- Neurology, Massachusetts General Hospital, Boston, USA,Univ. Lille, CHU Lille, Inserm U1172, Lille, France
| | - Maria Clara Zanon Zotin
- Neurology, Massachusetts General Hospital, Boston, USA,Ribeirão Preto Medical School, University of São Paulo, São Paulo, Brazil
| | | | | | - Sungmin Hong
- Neurology, Massachusetts General Hospital, Boston, USA
| | - Alvin S. Das
- Neurology, Massachusetts General Hospital, Boston, USA
| | | | - Justin E. Vranic
- Neurosurgery, Massachusetts General Hospital, Boston, USA,Radiology, Massachusetts General Hospital, Boston, USA
| | - Adam A. Dmytriw
- Neurosurgery, Massachusetts General Hospital, Boston, USA,Radiology, Massachusetts General Hospital, Boston, USA
| | | | - Aman B. Patel
- Neurosurgery, Massachusetts General Hospital, Boston, USA
| | | | | | - Thabele M. Leslie-Mazwi
- Neurosurgery, Massachusetts General Hospital, Boston, USA,Neurology, Massachusetts General Hospital, Boston, USA
| |
Collapse
|
5
|
Timing the Ischemic Stroke by Multiparametric Quantitative Magnetic Resonance Imaging. Stroke 2021. [DOI: 10.36255/exonpublications.stroke.timingischemicstroke.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
|
6
|
Anderssen KE, Syed S, Stormo SK. Quantification and mapping of tissue damage from freezing in cod by magnetic resonance imaging. Food Control 2021. [DOI: 10.1016/j.foodcont.2020.107734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
7
|
Turner AC, Schwamm LH, Etherton MR. Acute ischemic stroke: improving access to intravenous tissue plasminogen activator. Expert Rev Cardiovasc Ther 2020; 18:277-287. [PMID: 32323590 DOI: 10.1080/14779072.2020.1759422] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
INTRODUCTION Since approval by the United States Food and Drug Administration in 1996, alteplase utilization rates for acute ischemic stroke have increased. Despite its efficacy for improving stroke outcomes, however, the majority of ischemic stroke patients still do not receive alteplase. To address this issue, different methods for improving access to alteplase have been tested with varying degrees of success. AREAS COVERED This article gives an overview of the recent approaches pursued to improve access to alteplase for acute ischemic stroke patients. Utilization of stroke systems of care, quality metrics, and quality-improvement initiatives to improve alteplase treatment rates are discussed. The implementation of Telestroke networks to improve access and timely evaluation by a stroke specialist are also reviewed. Lastly, this review discusses the use of neuroimaging techniques to identify alteplase candidates in stroke of unknown symptom onset or beyond the 4.5-h treatment window. EXPERT COMMENTARY Expanding access to alteplase therapy for acute ischemic stroke is a multi-faceted approach. Specific considerations based on region, population, and health-care resources should be considered for each strategy. Neuroimaging approaches to identify alteplase-eligible patients beyond the 4.5-h treatment window are a recent development in acute stroke care that holds promise for increasing alteplase treatment rates.
Collapse
Affiliation(s)
- Ashby C Turner
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School , Boston, MA, USA
| | - Lee H Schwamm
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School , Boston, MA, USA
| | - Mark R Etherton
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School , Boston, MA, USA
| |
Collapse
|
8
|
Beer AL, Plank T, Greenlee MW. Aging and central vision loss: Relationship between the cortical macro-structure and micro-structure. Neuroimage 2020; 212:116670. [PMID: 32088318 DOI: 10.1016/j.neuroimage.2020.116670] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 02/13/2020] [Accepted: 02/17/2020] [Indexed: 12/17/2022] Open
Abstract
Aging and central vision loss are associated with cortical atrophies, but little is known about the relationship between cortical thinning and the underlying cellular structure. We compared the macro- and micro-structure of the cortical gray and superficial white matter of 38 patients with juvenile (JMD) or age-related (AMD) macular degeneration and 38 healthy humans (19-84 years) by multimodal MRI including diffusion-tensor imaging (DTI). A factor analysis showed that cortical thickness, tissue-dependent measures, and DTI-based measures were sensitive to distinct components of brain structure. Age-related cortical thinning and increased diffusion were observed across most of the cortex, but increased T1-weighted intensities (frontal), reduced T2-weighted intensities (occipital), and reduced anisotropy (medial) were limited to confined cortical regions. Vision loss was associated with cortical thinning and enhanced diffusion in the gray matter (less in the white matter) of the occipital central visual field representation. Moreover, AMD (but not JMD) patients showed enhanced diffusion in lateral occipito-temporal cortex and cortical thinning in the posterior cingulum. These findings demonstrate that changes in brain structure are best quantified by multimodal imaging. They further suggest that age-related brain atrophies (cortical thinning) reflect diverse micro-structural etiologies. Moreover, juvenile and age-related macular degeneration are associated with distinct patterns of micro-structural alterations.
Collapse
Affiliation(s)
- Anton L Beer
- Institut für Psychologie, Universität Regensburg, Regensburg, Germany.
| | - Tina Plank
- Institut für Psychologie, Universität Regensburg, Regensburg, Germany
| | - Mark W Greenlee
- Institut für Psychologie, Universität Regensburg, Regensburg, Germany
| |
Collapse
|
9
|
Chu ML, Chien CP, Wu WC, Chung HW. Gradient- and spin-echo (GRASE) MR imaging: a long-existing technology that may find wide applications in modern era. Quant Imaging Med Surg 2019; 9:1477-1484. [PMID: 31667134 DOI: 10.21037/qims.2019.09.13] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Mei-Lan Chu
- Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei, Taiwan.,Department of Biomedical Sciences and Engineering, National Central University, Taoyuan, Taiwan
| | - Cheng-Ping Chien
- Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei, Taiwan.,Department of Radiology, Taipei Beitou Health Management Hospital, Taipei, Taiwan
| | - Wen-Chau Wu
- Institute of Medical Device and Imaging, National Taiwan University, Taipei, Taiwan
| | - Hsiao-Wen Chung
- Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei, Taiwan
| |
Collapse
|
10
|
Damion RA, Knight MJ, McGarry BL, Bosnell R, Jezzard P, Harston GW, Carone D, Kennedy J, El-Tawil S, Elliot J, Muir KW, Clatworthy P, Kauppinen RA. Quantifying T 2 relaxation time changes within lesions defined by apparent diffusion coefficient in grey and white matter in acute stroke patients. Phys Med Biol 2019; 64:095016. [PMID: 30921782 DOI: 10.1088/1361-6560/ab1442] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The apparent diffusion coefficient (ADC) of cerebral water, as measured by diffusion MRI, rapidly decreases in ischaemia, highlighting a lesion in acute stroke patients. The MRI T 2 relaxation time changes in ischaemic brain such that T 2 in ADC lesions may be informative of the extent of tissue damage, potentially aiding in stratification for treatment. We have developed a novel user-unbiased method of determining the changes in T 2 in ADC lesions as a function of clinical symptom duration based on voxel-wise referencing to a contralateral brain volume. The spherical reference method calculates the most probable pre-ischaemic T 2 on a voxel-wise basis, making use of features of the contralateral hemisphere presumed to be largely unaffected. We studied whether T 2 changes in the two main cerebral tissue types, i.e. in grey matter (GM) and white matter (WM), would differ in stroke. Thirty-eight acute stroke patients were accrued within 9 h of symptom onset and scanned at 3 T for 3D T 1-weighted, multi b-value diffusion and multi-echo spin echo MRI for tissue type segmentation, quantitative ADC and absolute T 2 images, respectively. T 2 changes measured by the spherical reference method were 1.94 ± 0.61, 1.50 ± 0.52 and 1.40 ± 0.54 ms h-1 in the whole, GM, and WM lesions, respectively. Thus, T 2 time courses were comparable between GM and WM independent of brain tissue type involved. We demonstrate that T 2 changes in ADC-delineated lesions can be quantified in the clinical setting in a user unbiased manner and that T 2 change correlated with symptom onset time, opening the possibility of using the approach as a tool to assess severity of tissue damage in the clinical setting.
Collapse
Affiliation(s)
- Robin A Damion
- School of Psychological Science, University of Bristol, 12a Priory Rd, Bristol BS8 1TU, United Kingdom
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Ho KC, Scalzo F, Sarma KV, Speier W, El-Saden S, Arnold C. Predicting ischemic stroke tissue fate using a deep convolutional neural network on source magnetic resonance perfusion images. J Med Imaging (Bellingham) 2019; 6:026001. [PMID: 31131293 PMCID: PMC6529818 DOI: 10.1117/1.jmi.6.2.026001] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 04/18/2019] [Indexed: 01/09/2023] Open
Abstract
Predicting infarct volume from magnetic resonance perfusion-weighted imaging can provide helpful information to clinicians in deciding how aggressively to treat acute stroke patients. Models have been developed to predict tissue fate, yet these models are mostly built using hand-crafted features (e.g., time-to-maximum) derived from perfusion images, which are sensitive to deconvolution methods. We demonstrate the application of deep convolution neural networks (CNNs) on predicting final stroke infarct volume using only the source perfusion images. We propose a deep CNN architecture that improves feature learning and achieves an area under the curve of 0.871 ± 0.024 , outperforming existing tissue fate models. We further validate the proposed deep CNN with existing 2-D and 3-D deep CNNs for images/video classification, showing the importance of the proposed architecture. Our work leverages deep learning techniques in stroke tissue outcome prediction, advancing magnetic resonance imaging perfusion analysis one step closer to an operational decision support tool for stroke treatment guidance.
Collapse
Affiliation(s)
- King Chung Ho
- University of California, Los Angeles, Department of Bioengineering, Los Angeles, California, United States
| | - Fabien Scalzo
- University of California, Los Angeles, Department of Computer Science, Los Angeles, California, United States
| | - Karthik V. Sarma
- University of California, Los Angeles, Department of Bioengineering, Los Angeles, California, United States
| | - William Speier
- University of California, Los Angeles, Department of Radiological Sciences, Los Angeles, California, United States
| | - Suzie El-Saden
- University of California, Los Angeles, Department of Radiological Sciences, Los Angeles, California, United States
| | - Corey Arnold
- University of California, Los Angeles, Department of Radiological Sciences, Los Angeles, California, United States
| |
Collapse
|
12
|
Estimation of microvascular capillary physical parameters using MRI assuming a pseudo liquid drop as model of fluid exchange on the cellular level. Rep Pract Oncol Radiother 2018; 24:3-11. [PMID: 30337842 DOI: 10.1016/j.rpor.2018.09.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 04/30/2018] [Accepted: 09/06/2018] [Indexed: 11/20/2022] Open
Abstract
Aim One of the most important microvasculatures' geometrical variables is number of pores per capillary length that can be evaluated using MRI. The transportation of blood from inner to outer parts of the capillary is studied by the pores and the relationship among capillary wall thickness, size and the number of pores is examined. Background Characterization of capillary space may obtain much valuable information on the performance of tissues as well as the angiogenesis. Methods To estimate the number of pores, a new pseudo-liquid drop model along with appropriate quantitative physiological purposes has been investigated toward indicating a package of data on the capillary space. This model has utilized the MRI perfusion, diffusion and relaxivity parameters such as cerebral blood volume (CBV), apparent diffusion coefficient (ADC), ΔR 2 and Δ R 2 * values. To verify the model, a special protocol was designed and tested on various regions of eight male Wistar rats. Results The maximum number of pores per capillary length in the various conditions such as recovery, core, normal-recovery, and normal-core were found to be 183 ± 146, 176 ± 160, 275 ± 166, and 283 ± 143, respectively. This ratio in the normal regions was more than that of the damaged ones. The number of pores increased with increasing mean radius of the capillary and decreasing the thickness of the wall in the capillary space. Conclusion Determination of the number of capillary pore may most likely help to evaluate angiogenesis in the tissues and treatment planning of abnormal ones.
Collapse
Key Words
- 2DFT, two-dimensional Fourier transform
- ADC, apparent diffusion coefficient
- CBF, cerebral blood flow
- CBV, cerebral blood volume
- DWI, diffusion weighted imaging
- Diameter
- Diffusion MRI
- FLASH, fast low angle shot
- FOV, field of view
- MCA, middle cerebral artery
- MTT, mean transit time
- Microvasculature
- PWI, perfusion weighted imaging
- Pores
- Pseudo-liquid drop model
- RF, radio frequency
- ROI, region of interest
- TCL, total capillary length
- VSI, vessel size index
- Wistar rats
Collapse
|
13
|
Khodanovich MY, Kisel AA, Akulov AE, Atochin DN, Kudabaeva MS, Glazacheva VY, Svetlik MV, Medvednikova YA, Mustafina LR, Yarnykh VL. Quantitative assessment of demyelination in ischemic stroke in vivo using macromolecular proton fraction mapping. J Cereb Blood Flow Metab 2018; 38:919-931. [PMID: 29372644 PMCID: PMC5987939 DOI: 10.1177/0271678x18755203] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A recent MRI method, fast macromolecular proton fraction (MPF) mapping, was used to quantify demyelination in the transient middle cerebral artery occlusion (MCAO) rat stroke model. MPF and other quantitative MRI parameters (T1, T2, proton density, and apparent diffusion coefficient) were compared with histological and immunohistochemical markers of demyelination (Luxol Fast Blue stain, (LFB)), neuronal loss (NeuN immunofluorescence), axonal loss (Bielschowsky stain), and inflammation (Iba1 immunofluorescence) in three animal groups ( n = 5 per group) on the 1st, 3rd, and 10th day after MCAO. MPF and LFB optical density (OD) were significantly reduced in the ischemic lesion on all days after MCAO relative to the symmetrical regions of the contralateral hemisphere. Percentage changes in MPF and LFB OD in the ischemic lesion relative to the contralateral hemisphere significantly differed on the first day only. Percentage changes in LFB OD and MPF were strongly correlated (R = 0.81, P < 0.001) and did not correlate with other MRI parameters. MPF also did not correlate with other histological variables. Addition of T2 into multivariate regression further improved agreement between MPF and LFB OD (R = 0.89, P < 0.001) due to correction of the edema effect. This study provides histological validation of MPF as an imaging biomarker of demyelination in ischemic stroke.
Collapse
Affiliation(s)
| | - Alena A Kisel
- 1 Laboratory of Neurobiology, Tomsk State University, Tomsk, Russian Federation
| | - Andrey E Akulov
- 1 Laboratory of Neurobiology, Tomsk State University, Tomsk, Russian Federation.,2 Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russian Federation
| | - Dmitriy N Atochin
- 1 Laboratory of Neurobiology, Tomsk State University, Tomsk, Russian Federation.,3 Cardiovascular Research Center, Harvard Medical School, Massachusetts General Hospital, Boston, MA, USA.,4 RASA Center in Tomsk, Tomsk Polytechnic University, Tomsk, Russian Federation
| | - Marina S Kudabaeva
- 1 Laboratory of Neurobiology, Tomsk State University, Tomsk, Russian Federation
| | | | - Michael V Svetlik
- 1 Laboratory of Neurobiology, Tomsk State University, Tomsk, Russian Federation
| | - Yana A Medvednikova
- 1 Laboratory of Neurobiology, Tomsk State University, Tomsk, Russian Federation
| | - Lilia R Mustafina
- 5 Department of Histology, Embryology and Cytology, Siberian State Medical University, Tomsk, Russian Federation
| | - Vasily L Yarnykh
- 1 Laboratory of Neurobiology, Tomsk State University, Tomsk, Russian Federation.,6 Department of Radiology, University of Washington, Seattle, WA, USA
| |
Collapse
|
14
|
Schwamm LH, Wu O, Song SS, Latour LL, Ford AL, Hsia AW, Muzikansky A, Betensky RA, Yoo AJ, Lev MH, Boulouis G, Lauer A, Cougo P, Copen WA, Harris GJ, Warach S. Intravenous thrombolysis in unwitnessed stroke onset: MR WITNESS trial results. Ann Neurol 2018; 83:980-993. [PMID: 29689135 DOI: 10.1002/ana.25235] [Citation(s) in RCA: 98] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 04/08/2018] [Accepted: 04/12/2018] [Indexed: 11/09/2022]
Abstract
OBJECTIVE Most acute ischemic stroke (AIS) patients with unwitnessed symptom onset are ineligible for intravenous thrombolysis due to timing alone. Lesion evolution on fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI) correlates with stroke duration, and quantitative mismatch of diffusion-weighted MRI with FLAIR (qDFM) might indicate stroke duration within guideline-recommended thrombolysis. We tested whether intravenous thrombolysis ≤4.5 hours from the time of symptom discovery is safe in patients with qDFM in an open-label, phase 2a, prospective study (NCT01282242). METHODS Patients aged 18 to 85 years with AIS of unwitnessed onset at 4.5 to 24 hours since they were last known to be well, treatable within 4.5 hours of symptom discovery with intravenous alteplase (0.9mg/kg), and presenting with qDFM were screened across 14 hospitals. The primary outcome was the risk of symptomatic intracranial hemorrhage (sICH) with preplanned stopping rules. Secondary outcomes included symptomatic brain edema risk, and functional outcomes of 90-day modified Rankin Scale (mRS). RESULTS Eighty subjects were enrolled between January 31, 2011 and October 4, 2015 and treated with alteplase at median 11.2 hours (IQR = 9.5-13.3) from when they were last known to be well. There was 1 sICH (1.3%) and 3 cases of symptomatic edema (3.8%). At 90 days, 39% of subjects achieved mRS = 0-1, as did 48% of subjects who had vessel imaging and were without large vessel occlusions. INTERPRETATION Intravenous thrombolysis within 4.5 hours of symptom discovery in patients with unwitnessed stroke selected by qDFM, who are beyond the recommended time windows, is safe. A randomized trial testing efficacy using qDFM appears feasible and is warranted in patients without large vessel occlusions. Ann Neurol 2018;83:980-993.
Collapse
Affiliation(s)
- Lee H Schwamm
- Department of Neurology, Massachusetts General Hospital, Boston, MA
| | - Ona Wu
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA
| | - Shlee S Song
- Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Lawrence L Latour
- Acute Cerebrovascular Diagnostics Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
| | - Andria L Ford
- Department of Neurology, Washington University School of Medicine, St Louis, MO
| | - Amie W Hsia
- Acute Cerebrovascular Diagnostics Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD.,Comprehensive Stroke Center, MedStar Washington Hospital Center, Washington, DC
| | | | - Rebecca A Betensky
- Massachusetts General Hospital Biostatistics Center, Boston, MA.,Harvard T. H. Chan School of Public Health, Boston, MA
| | - Albert J Yoo
- Neuroendovascular Service, Texas Stroke Institute, Plano, TX.,Department of Radiology, Massachusetts General Hospital, Boston, MA
| | - Michael H Lev
- Department of Radiology, Massachusetts General Hospital, Boston, MA
| | - Gregoire Boulouis
- Department of Neurology, Massachusetts General Hospital, Boston, MA.,Department of Neuroradiology, Paris Descartes University, Saint Anne Hospital Center, Paris, France
| | - Arne Lauer
- Department of Neurology, Massachusetts General Hospital, Boston, MA
| | - Pedro Cougo
- Department of Neurology, Massachusetts General Hospital, Boston, MA
| | - William A Copen
- Department of Radiology, Massachusetts General Hospital, Boston, MA
| | - Gordon J Harris
- Department of Radiology, Massachusetts General Hospital, Boston, MA
| | - Steven Warach
- Dell Medical School, University of Texas at Austin, Austin, TX
| | | |
Collapse
|
15
|
Duchêne G, Peeters F, Peeters A, Duprez T. A comparative study of the sensitivity of diffusion-related parameters obtained from diffusion tensor imaging, diffusional kurtosis imaging, q-space analysis and bi-exponential modelling in the early disease course (24 h) of hyperacute (6 h) ischemic stroke patients. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2017; 30:375-385. [DOI: 10.1007/s10334-017-0612-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 02/20/2017] [Accepted: 02/21/2017] [Indexed: 12/21/2022]
|
16
|
Revisiting Current Golden Rules in Managing Acute Ischemic Stroke: Evaluation of New Strategies to Further Improve Treatment Selection and Outcome. AJR Am J Roentgenol 2017; 208:32-41. [DOI: 10.2214/ajr.16.16557] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
17
|
Knight MJ, McGarry BL, Rogers HJ, Jokivarsi KT, Gröhn OHJ, Kauppinen RA. A spatiotemporal theory for MRI T2 relaxation time and apparent diffusion coefficient in the brain during acute ischaemia: Application and validation in a rat acute stroke model. J Cereb Blood Flow Metab 2016; 36:1232-43. [PMID: 26661188 PMCID: PMC4929697 DOI: 10.1177/0271678x15608394] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 06/22/2015] [Indexed: 01/20/2023]
Abstract
The objective of this study is to present a mathematical model which can describe the spatiotemporal progression of cerebral ischaemia and predict magnetic resonance observables including the apparent diffusion coefficient (ADC) of water and transverse relaxation time T2 This is motivated by the sensitivity of the ADC to the location of cerebral ischaemia and T2 to its time-course, and that it has thus far proven challenging to relate observations of changes in these MR parameters to stroke timing, which is of considerable importance in making treatment choices in clinics. Our mathematical model, called the cytotoxic oedema/dissociation (CED) model, is based on the transit of water from the extra- to the intra-cellular environment (cytotoxic oedema) and concomitant degradation of supramacromolecular and macromolecular structures (such as microtubules and the cytoskeleton). It explains experimental observations of ADC and T2, as well as identifying the rate of spread of effects of ischaemia through a tissue as a dominant system parameter. The model brings the direct extraction of the timing of ischaemic stroke from quantitative MRI closer to reality, as well as providing insight on ischaemia pathology by imaging in general. We anticipate that this may improve patient access to thrombolytic treatment as a future application.
Collapse
Affiliation(s)
- Michael J Knight
- School of Experimental Psychology and Clinical Research and Imaging Centre Bristol, University of Bristol, Bristol, UK
| | - Bryony L McGarry
- School of Experimental Psychology and Clinical Research and Imaging Centre Bristol, University of Bristol, Bristol, UK
| | - Harriet J Rogers
- School of Experimental Psychology and Clinical Research and Imaging Centre Bristol, University of Bristol, Bristol, UK
| | - Kimmo T Jokivarsi
- Department of Neurobiology, A.I. Virtanen Institute, University of Eastern Finland, Kuopio, Finland
| | - Olli H J Gröhn
- Department of Neurobiology, A.I. Virtanen Institute, University of Eastern Finland, Kuopio, Finland
| | - Risto A Kauppinen
- School of Experimental Psychology and Clinical Research and Imaging Centre Bristol, University of Bristol, Bristol, UK
| |
Collapse
|
18
|
Chakkarapani E, Poskitt KJ, Miller SP, Zwicker JG, Xu Q, Wong DST, Roland EH, Hill A, Chau V. Reliability of Early Magnetic Resonance Imaging (MRI) and Necessity of Repeating MRI in Noncooled and Cooled Infants With Neonatal Encephalopathy. J Child Neurol 2016; 31:553-9. [PMID: 26323498 DOI: 10.1177/0883073815600865] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2015] [Accepted: 07/16/2015] [Indexed: 11/17/2022]
Abstract
In cooled newborns with encephalopathy, although late magnetic resonance imaging (MRI) scan (10-14 days of age) is reliable in predicting long-term outcome, it is unknown whether early scan (3-6 days of life) is. We compared the predominant pattern and extent of lesion between early and late MRI in 89 term neonates with neonatal encephalopathy. Forty-three neonates (48%) were cooled. The predominant pattern of lesions and the extent of lesion in the watershed region agreed near perfectly in noncooled (kappa = 0.94; k = 0.88) and cooled (k = 0.89; k = 0.87) infants respectively. There was perfect agreement in the extent of lesion in the basal nuclei in noncooled infants (k = 0.83) and excellent agreement in cooled infants (k = 0.67). Changes in extent of lesions on late MRI occurred in 19 of 89 infants, with higher risk in infants with hypoglycemia and moderate-severe lesions in basal nuclei. In most term neonates with neonatal encephalopathy, early MRI (relative to late scan) robustly predicts the predominant pattern and extent of injury.
Collapse
Affiliation(s)
- Elavazhagan Chakkarapani
- Department of Pediatrics (Neonatology), University of British Columbia and BC Children's Hospital, Vancouver, British Columbia, Canada Department of Pediatrics (Neurology), University of British Columbia and BC Children's Hospital, Vancouver, British Columbia, Canada School of Clinical Sciences, University of Bristol, St Michael's Hospital, Bristol, United Kingdom
| | - Kenneth J Poskitt
- Department of Pediatrics (Neurology), University of British Columbia and BC Children's Hospital, Vancouver, British Columbia, Canada Department of Radiology, University of British Columbia and BC Children's Hospital, Vancouver, British Columbia, Canada
| | - Steven P Miller
- Department of Pediatrics (Neonatology), University of British Columbia and BC Children's Hospital, Vancouver, British Columbia, Canada Child and Family Research Institute, Vancouver, British Columbia, Canada Department of Pediatrics (Neurology), University of Toronto and the Hospital for Sick Children, Toronto, Ontario, Canada Neurosciences & Mental Health Research Institute, Toronto, Ontario, Canada
| | - Jill G Zwicker
- Department of Pediatrics (Developmental Pediatrics), University of British Columbia and BC Children's Hospital, Vancouver, British Columbia, Canada Department of Occupational Science and Occupational Therapy, Vancouver, British Columbia, Canada Child and Family Research Institute, Vancouver, British Columbia, Canada Sunny Hill Health Centre for Children, Vancouver, British Columbia, Canada
| | - Qi Xu
- Department of Pediatrics (Neurology), University of British Columbia and BC Children's Hospital, Vancouver, British Columbia, Canada
| | - Darren S T Wong
- Department of Pediatrics (Neurology), University of British Columbia and BC Children's Hospital, Vancouver, British Columbia, Canada
| | - Elke H Roland
- Department of Pediatrics (Neurology), University of British Columbia and BC Children's Hospital, Vancouver, British Columbia, Canada
| | - Alan Hill
- Department of Pediatrics (Neurology), University of British Columbia and BC Children's Hospital, Vancouver, British Columbia, Canada
| | - Vann Chau
- Child and Family Research Institute, Vancouver, British Columbia, Canada Department of Pediatrics (Neurology), University of Toronto and the Hospital for Sick Children, Toronto, Ontario, Canada Neurosciences & Mental Health Research Institute, Toronto, Ontario, Canada
| |
Collapse
|
19
|
Morgan CD, Stephens M, Zuckerman SL, Waitara MS, Morone PJ, Dewan MC, Mocco J. Physiologic imaging in acute stroke: Patient selection. Interv Neuroradiol 2015; 21:499-510. [PMID: 26063695 DOI: 10.1177/1591019915587227] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Treatment of acute stroke is changing, as endovascular intervention becomes an important adjunct to tissue plasminogen activator. An increasing number of sophisticated physiologic imaging techniques have unique advantages and applications in the evaluation, diagnosis, and treatment-decision making of acute ischemic stroke. In this review, we first highlight the strengths, weaknesses, and possible indications for various stroke imaging techniques. How acute imaging findings in each modality have been used to predict functional outcome is discussed. Furthermore, there is an increasing emphasis on using these state-of-the-art imaging modalities to offer maximal patient benefit through IV therapy, endovascular thrombolytics, and clot retrieval. We review the burgeoning literature in the determination of stroke treatment based on acute, physiologic imaging findings.
Collapse
Affiliation(s)
- Clinton D Morgan
- Department of Neurological Surgery, Vanderbilt University School of Medicine, USA
| | | | - Scott L Zuckerman
- Department of Neurological Surgery, Vanderbilt University School of Medicine, USA
| | | | - Peter J Morone
- Department of Neurological Surgery, Vanderbilt University School of Medicine, USA
| | - Michael C Dewan
- Department of Neurological Surgery, Vanderbilt University School of Medicine, USA
| | - J Mocco
- Department of Neurosurgery, Icahn School of Medicine at Mouth Sinai, USA
| |
Collapse
|
20
|
Squillaci E, Bolacchi F, Altobelli S, Franceschini L, Bergamini A, Cantonetti M, Simonetti G. Pre-treatment staging of multiple myeloma patients: comparison of whole-body diffusion weighted imaging with whole-body T1-weighted contrast-enhanced imaging. Acta Radiol 2015; 56:733-8. [PMID: 24973257 DOI: 10.1177/0284185114538792] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Accepted: 05/14/2014] [Indexed: 11/16/2022]
Abstract
BACKGROUND Multiple myeloma (MM) is a hematologic malignancy characterized by the clonal proliferation of plasma cells. Accurate staging is of pivotal importance in the management of MM. Advanced imaging techniques, such as magnetic resonance imaging (MRI), are increasingly used for the initial diagnosis and staging of MM. PURPOSE To compare whole-body (WB) MR diffusion-weighted imaging with background body signal suppression (DWIBS) with (WB) MR fat-suppressed T1-weighted contrast-enhanced imaging (T1-CE) in the pre-treatment staging evaluation of multiple myeloma (MM) patients. MATERIAL AND METHODS Thirty-six patients with MM were included in the study. T1-CE and DWIBS were performed using a 3 T scanner. The Durie-Salmon plus staging system was used. Kappa statistics was used to assess agreement. RESULTS For all MM stages good to very good agreement was found for both T1-CE and DWIBS. The unweighted kappa statistic indicated a moderate, good and very good agreement between T1-CE and DWIBS for stages I, II, and III, respectively. In particular, in 67% of patients the MM staging according to T1-CE was not different from DWIBS. In the remaining 33% of patients, the MM stage obtained with T1-CE was lower than that provided by DWIBS. CONCLUSION DWIBS and T1-CE were concordant in the majority of patients. In a minority of cases DWIBS evidenced areas of water restriction that did not correspond to contrast enhancement areas. Studies monitoring therapeutic response in relation to tumour burden and aggressiveness should be performed to assess the clinical relevance of DWIBS findings.
Collapse
Affiliation(s)
- Ettore Squillaci
- University Hospital Policlinico Tor Vergata, Department of Diagnostic Imaging, Molecular Imaging, Interventional Radiology and Radiation Therapy, University of Rome “Tor Vergata”, Rome, Italy
| | - Francesca Bolacchi
- University Hospital Policlinico Tor Vergata, Department of Diagnostic Imaging, Molecular Imaging, Interventional Radiology and Radiation Therapy, University of Rome “Tor Vergata”, Rome, Italy
| | - Simone Altobelli
- University Hospital Policlinico Tor Vergata, Department of Diagnostic Imaging, Molecular Imaging, Interventional Radiology and Radiation Therapy, University of Rome “Tor Vergata”, Rome, Italy
| | - Luca Franceschini
- Department of Internal Medicine, Hematology/Oncology Unit, Tor Vergata University, Rome, Italy
| | - Alberto Bergamini
- Department of Internal Medicine, Hematology/Oncology Unit, Tor Vergata University, Rome, Italy
- Department of Public Health and Cellular Biology, University of Rome “Tor Vergata”, Rome, Italy
| | - Maria Cantonetti
- Department of Internal Medicine, Hematology/Oncology Unit, Tor Vergata University, Rome, Italy
| | - Giovanni Simonetti
- University Hospital Policlinico Tor Vergata, Department of Diagnostic Imaging, Molecular Imaging, Interventional Radiology and Radiation Therapy, University of Rome “Tor Vergata”, Rome, Italy
| |
Collapse
|
21
|
Kretzer L, Gräßel D, Bokemeyer MA, Günther A, Witte OW, Axer H, Ringer TM. Effect of Intravenous Thrombolysis on the Time Course of the Apparent Diffusion Coefficient in Acute Middle Cerebral Artery Infarction. J Neuroimaging 2015; 25:978-82. [PMID: 25895155 DOI: 10.1111/jon.12240] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 01/30/2015] [Accepted: 02/22/2015] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE To examine the possible effects of intravenous thrombolysis on the time course of the apparent diffusion coefficient in the patients with acute middle cerebral artery infarct. METHODS Serial MRI data with all in all 190 MR examinations including diffusion-weighted imaging (DWI), apparent diffusion coefficient map (ADC map) and T2 -weighted imaging (T2 w) of 74 patients with initial intravenous thrombolysis (study group; N = 37) or conservative stroke treatment (control group; N = 37) were retrospectively analyzed. A trend function was fitted to the relative values (rADC, rDWI, rT2 w) to model an objective, general time course. RESULTS Relative apparent diffusion coefficient (rADC) decreased in both groups to a minimum about 15 hours after symptom onset. Afterwards rADC increased faster in the study group and reached pseudonormalization 5 ± 2 days after symptom onset. In the control group pseudonormalization was determined later at 7 ± 6 days after symptom onset. After pseudonormalization rADC continued to increase in both groups. CONCLUSION rADC pseudonormalization occurred by trend earlier in the study group. Therefore, intravenous thrombolysis seems to have an effect on the time course of ADC, which is likely to be due to earlier cerebral reperfusion after thrombolysis. In addition, initial stroke treatment as thrombolysis should be considered in radiological rating of stroke MRI time course.
Collapse
Affiliation(s)
- Lydia Kretzer
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
| | - David Gräßel
- Institute of Neuroscience and Medicine (INM-1), Research Centre Jülich, Jülich, Germany
| | | | - Albrecht Günther
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
| | - Otto W Witte
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany.,Center for Sepsis Control and Care (CSCC), Jena University Hospital, Germany
| | - Hubertus Axer
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany.,Center for Sepsis Control and Care (CSCC), Jena University Hospital, Germany
| | - Thomas M Ringer
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
| |
Collapse
|
22
|
Kimberly WT, Battey TWK, Pham L, Wu O, Yoo AJ, Furie KL, Singhal AB, Elm JJ, Stern BJ, Sheth KN. Glyburide is associated with attenuated vasogenic edema in stroke patients. Neurocrit Care 2014; 20:193-201. [PMID: 24072459 DOI: 10.1007/s12028-013-9917-z] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND Brain edema is a serious complication of ischemic stroke that can lead to secondary neurological deterioration and death. Glyburide is reported to prevent brain swelling in preclinical rodent models of ischemic stroke through inhibition of a non-selective channel composed of sulfonylurea receptor 1 and transient receptor potential cation channel subfamily M member 4. However, the relevance of this pathway to the development of cerebral edema in stroke patients is not known. METHODS Using a case-control design, we retrospectively assessed neuroimaging and blood markers of cytotoxic and vasogenic edema in subjects who were enrolled in the glyburide advantage in malignant edema and stroke-pilot (GAMES-Pilot) trial. We compared serial brain magnetic resonance images (MRIs) to a cohort with similar large volume infarctions. We also compared matrix metalloproteinase-9 (MMP-9) plasma level in large hemispheric stroke. RESULTS We report that IV glyburide was associated with T2 fluid-attenuated inversion recovery signal intensity ratio on brain MRI, diminished the lesional water diffusivity between days 1 and 2 (pseudo-normalization), and reduced blood MMP-9 level. CONCLUSIONS Several surrogate markers of vasogenic edema appear to be reduced in the setting of IV glyburide treatment in human stroke. Verification of these potential imaging and blood biomarkers is warranted in the context of a randomized, placebo-controlled trial.
Collapse
Affiliation(s)
- W Taylor Kimberly
- Center for Human Genetic Research and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA,
| | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Juang CL, Yang FS, Hsieh MS, Tseng HY, Chen SC, Wen HC. Investigation of anti-oxidative stress in vitro and water apparent diffusion coefficient in MRI on rat after spinal cord injury in vivo with Tithonia diversifolia ethanolic extracts treatment. Altern Ther Health Med 2014; 14:447. [PMID: 25407401 PMCID: PMC4289305 DOI: 10.1186/1472-6882-14-447] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Accepted: 08/18/2014] [Indexed: 01/06/2023]
Abstract
BACKGROUND Spinal cord injury (SCI)-induced secondary oxidative stress associates with a clinical complication and high mortality. Treatments to improve the neurological outcome of secondary injury are considered as important issues. The objective of the current study is to evaluate the anti-oxidative effect of Tithonia diversifolia ethanolic extracts (TDE) on cells and apply the pharmacological effect to SCI model using a MRI imaging algorism. METHODS The anti-oxidation properties were tested in a 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Rat liver cells (clone-9) were treated with various doses of TDE (0 ~ 50 μg/ml) before exposed to 250 μM H2O2 and cell survival was determined by MTT and LDH assays. We performed water apparent diffusion coefficient (ADC) map in MR techniques to investigate the efficacy of TDE treatment on SCI animal model. We performed T5 laminectomy and compression (50 g, 1 min) to induce SCI. PHILIP 3.0 T MRI was used to image 24 male Sprague-Dawley rats weighing 280-320 g. Rats were randomly divided into three groups: sham group, SCI group, SCI treated with TDE group. The MRI images were taken and ADC were acquired before and after of treatment of TDE (50 mg/kg B. W. orally, 5 days) in SCI model. RESULTS TDE protected clone-9 cells against H2O2-induced toxicity through DPPH scavenging mechanism. In addition, SCI induced the increase in ADC after 6 hours. TDE treatment slightly decreased the ADC level after 1-week SCI compared with control animals. CONCLUSION Our studies have proved that the cytoprotection effect of TDE, at least in part, is through scavenging ROS to eliminate intracellular oxidative stress and highlight a potential therapeutic consideration of TDE in alternative and complementary medicine.
Collapse
|
24
|
Lesion segmentation from multimodal MRI using random forest following ischemic stroke. Neuroimage 2014; 98:324-35. [DOI: 10.1016/j.neuroimage.2014.04.056] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 03/26/2014] [Accepted: 04/21/2014] [Indexed: 11/17/2022] Open
|
25
|
Kauppinen RA. Multiparametric magnetic resonance imaging of acute experimental brain ischaemia. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2014; 80:12-25. [PMID: 24924265 DOI: 10.1016/j.pnmrs.2014.05.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Revised: 05/07/2014] [Accepted: 05/07/2014] [Indexed: 06/03/2023]
Abstract
Ischaemia is a condition in which blood flow either drops to zero or proceeds at severely decreased levels that cannot supply sufficient oxidizable substrates to maintain energy metabolism in vivo. Brain, a highly oxidative organ, is particularly susceptible to ischaemia. Ischaemia leads to loss of consciousness in seconds and, if prolonged, permanent tissue damage is inevitable. Ischaemia primarily results in a collapse of cerebral energy state, followed by a series of subtle changes in anaerobic metabolism, ion and water homeostasis that eventually initiate destructive internal and external processes in brain tissue. (31)P and (1)H NMR spectroscopy were initially used to evaluate anaerobic metabolism in brain. However, since the early 1990s (1)H Magnetic Resonance Imaging (MRI), exploiting the nuclear magnetism of tissue water, has become the key method for assessment of ischaemic brain tissue. This article summarises multi-parametric (1)H MRI work that has exploited diffusion, relaxation and magnetisation transfer as 'contrasts' to image ischaemic brain in preclinical models for the first few hours, with a view to assessing evolution of ischaemia and tissue viability in a non-invasive manner.
Collapse
Affiliation(s)
- Risto A Kauppinen
- School of Experimental Psychology and Clinical Research and Imaging Centre, University of Bristol, 12a Priory Road, Bristol BS8 1TU, UK.
| |
Collapse
|
26
|
Fiebach JB, Galinovic I. MR Imaging for Acute Stroke. CURRENT RADIOLOGY REPORTS 2014. [DOI: 10.1007/s40134-014-0053-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
27
|
Abstract
Quantitative measurement of blood-brain barrier (BBB) permeability using MRI and its application to cerebral ischemia are reviewed. Measurement of BBB permeability using MRI has been employed to evaluate ischemic damage during acute and subacute phases of stroke and to predict hemorrhagic transformation. There is also an emerging interest on the development and use of MRI to monitor vascular structural changes and angiogenesis during stroke recovery. In this review, we describe MRI BBB permeability and susceptibility-weighted MRI measurements and its applications to evaluate ischemic damage during the acute and subacute phases of stroke and vascular remodeling during stroke recovery.
Collapse
|
28
|
Abstract
Stroke is a serious healthcare problem with high mortality and long-term disability. However, to date, our ability to prevent and cure stroke remains limited. One important goal in stroke research is to identify the extent and location of lesion for treatment. In addition, accurately differentiating salvageable tissue from infarct and evaluating therapeutic efficacies are indispensible. These objectives could potentially be met with the assistance of modern neuroimaging techniques. This paper reviews current imaging methods commonly used in ischemic stroke research. These methods include positron emission tomography, computed tomography, T1 MRI, T2 MRI, diffusion and perfusion MRI, diffusion tensor imaging, blood-brain barrier permeability MRI, pH-weighted MRI, and functional MRI.
Collapse
Affiliation(s)
- Hsiao-Ying Wey
- University of Texas Health Science Center, San Antonio, Texas, USA
| | | | | |
Collapse
|
29
|
Cheng B, Rosenkranz M, Krützelmann A, Fiehler J, Forkert ND, Gerloff C, Thomalla G. The extent of perfusion deficit does not relate to the visibility of acute ischemic lesions on fluid-attenuated inversion recovery imaging. J Neuroimaging 2012; 23:215-8. [PMID: 22818219 DOI: 10.1111/j.1552-6569.2012.00708.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVES Fluid-attenuated inversion recovery imaging (FLAIR) has been suggested as a surrogate marker of lesion age in acute ischemic stroke. In a subgroup analysis, we evaluated whether the extent of perfusion deficit influences FLAIR lesion visibility and thus plays a role as a confounding variable in the interpretation of FLAIR images. METHODS A subgroup of patients from a previous study evaluating the use of FLAIR imaging as a surrogate marker of lesion age within the first 6 hours of ischemic stroke were examined to determine the influence of the amount of perfusion deficit on FLAIR lesion visibility. RESULTS N = 48 patients were included into the analysis. In positive and negative FLAIR lesion cases the extent of perfusion deficits did not differ significantly (150 mL vs. 197 mL, P = .730) nor influenced FLAIR visibility independently. In contrast, diffusion weighted imaging (DWI) lesion volumes were larger (34 mL vs. 14 mL, P = .008) and time from symptom onset longer (180 vs. 120 minute, P = .071) in FLAIR-positive cases. CONCLUSION Visibility of FLAIR lesions in acute stroke imaging is influenced by lesion size and time from symptom onset to MRI, but not by the amount of perfusion deficit calculated by time-to-peak (TTP) measurements.
Collapse
Affiliation(s)
- Bastian Cheng
- Klinik und Poliklinik für Neurologie, Kopf- und Neurozentrum, Universitätsklinikum Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany.
| | | | | | | | | | | | | |
Collapse
|
30
|
Nehlig A. Hippocampal MRI and other structural biomarkers: experimental approach to epileptogenesis. Biomark Med 2012; 5:585-97. [PMID: 22003907 DOI: 10.2217/bmm.11.65] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The present review is devoted to application of MRI techniques to the epileptic brain and the search for potential biomarkers of epileptogenicity and/or epileptogenesis in rodents that could be translated to the clinic. Diffusion-weighted imaging reveals very early changes in water movements. T(2)-weighted hypersignal indicates edema or gliosis within brain regions and is most often used along with histological assessment of neuronal loss. (31)P magnetic resonance spectroscopy measures the energy reserve of the tissue while (1)H spectroscopy assesses neuronal loss and mitochondrial dysfunction. (13)C spectroscopy analyzes, separately, neuronal and astrocytic metabolism and interactions between the two cell types. Finally, diffusion tensor imaging and tractography have been applied to the study of plasticity and show a good coherence with circuit changes assessed by Timm staining. The potential of these techniques as reliable biomarkers of epileptogenesis is still disputed. At the moment, one study has provided a reliable temporal evolution of the T(2) signal, predicting epileptogenesis in 100% of the cases, and further imaging approaches based on the techniques described here are still needed to identify potential early imaging biomarkers of epileptogenicity and/or epileptogenesis.
Collapse
Affiliation(s)
- Astrid Nehlig
- INSERM U 666, Faculty of Medicine, 11 rue Humann, 67085 Strasbourg Cedex, France.
| |
Collapse
|
31
|
|
32
|
Brain irradiation improves focal cerebral ischemia recovery in aged rats. J Neurol Sci 2011; 306:143-53. [DOI: 10.1016/j.jns.2011.02.034] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2010] [Revised: 01/21/2011] [Accepted: 02/28/2011] [Indexed: 12/14/2022]
|
33
|
Fung SH, Roccatagliata L, Gonzalez RG, Schaefer PW. MR Diffusion Imaging in Ischemic Stroke. Neuroimaging Clin N Am 2011; 21:345-77, xi. [DOI: 10.1016/j.nic.2011.03.001] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
|
34
|
Abstract
Stroke is a leading cause of death and adult morbidity worldwide. By defining stroke symptom onset by the time the patient was last known to be well, many patients whose onsets are unwitnessed are automatically ineligible for thrombolytic therapy. Advanced brain imaging may serve as a substitute witness to estimate stroke onset and duration in those patients who do not have a human witness. This article reviews and compares some of these imaging-based approaches to thrombolysis eligibility, which can potentially expand the use of thrombolytic therapy to a broader population of acute stroke patients.
Collapse
Affiliation(s)
- Ona Wu
- Department of Radiology, MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, MGH, 149 Thirteenth Street Suite 2301, Charlestown, MA 02129, USA.
| | | | | |
Collapse
|
35
|
Gokcay F, Arsava EM, Baykaner T, Vangel M, Garg P, Wu O, Singhal AB, Furie KL, Sorensen AG, Ay H. Age-dependent susceptibility to infarct growth in women. Stroke 2011; 42:947-51. [PMID: 21311058 DOI: 10.1161/strokeaha.110.603902] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND PURPOSE It is not known if there is a relationship between gender and tissue outcome in human ischemic stroke. We sought to identify whether the proportion of initially ischemic to eventually infarcted tissue was different between men and women with ischemic stroke. METHODS We studied 141 consecutive patients with acute ischemic stroke who had a baseline MRI obtained within 12 hours of symptom onset, a follow-up imaging on Day 4 or later, and diffusion-weighted imaging/mean transmit time mismatch on initial MRI. Lesion growth was calculated as percentage of mismatch tissue that underwent infarction on follow-up (percentage mismatch lost). Multivariable analyses explored the effect of gender and other predictors of tissue outcome on percentage mismatch lost. RESULTS There was no difference in median percentage mismatch lost between men (19%) and women (11%; P=0.720). There was, however, an interaction between gender and age; median percentage mismatch lost was 7% (0% to 12%) in women and 18% (1% to 35%) in men younger than the population median (71 years, P=0.061). The percentage mismatch lost was not different between men and women ≥71 years old (25% in both groups). The linear regression model revealed gender (P=0.027) and the interaction between age and gender (P=0.023) as independent predictors of percentage mismatch lost. CONCLUSIONS There is an age-by-gender interaction in tissue outcome after ischemic stroke; brain infarcts in women <70 years grow approximately 50% less than infarcts in their male counterparts. These findings extend the well-known concept that there is a differential age-by-gender effect on stroke incidence, mortality, and functional outcome to the tissue level.
Collapse
Affiliation(s)
- Figen Gokcay
- AA Martinos Center for Biomedical Imaging and Stroke Service, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 13th Street, Room 2301, Charlestown, MA 02129, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Petkova M, Rodrigo S, Lamy C, Oppenheim G, Touzé E, Mas JL, Méder JF, Oppenheim C. MR Imaging Helps Predict Time from Symptom Onset in Patients with Acute Stroke: Implications for Patients with Unknown Onset Time. Radiology 2010; 257:782-92. [DOI: 10.1148/radiol.10100461] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
37
|
Jacobs MA, Gultekin DH, Kim HS. Comparison between diffusion-weighted imaging, T2-weighted, and postcontrast T1-weighted imaging after MR-guided, high intensity, focused ultrasound treatment of uterine leiomyomata: preliminary results. Med Phys 2010; 37:4768-76. [PMID: 20964196 DOI: 10.1118/1.3475940] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
PURPOSE To investigate the comparison between diffusion-weighted imaging (DWI), T2-weighted imaging, (T2WI) and contrast T1-weighted imaging (cT1WI) in uterine leiomyoma following treatment by magnetic resonance imaging-guided, high intensity focused ultrasound surgery (MRg-HIFUS). METHODS Twenty one patients (45 +/- 5 yrs) with clinical symptoms of uterine leiomyoma (fibroids) were treated by MRg-HIFUS using an integrated 1.5T MRI-HIFUS system. MRI parameters consisted of DWI, T2WI, and T1-weighted fast spoiled gradient echo before and after contrast. The post-MRg-HIFUS treatment volume in the fibroid was assessed by cT1WI and DWI. Trace apparent diffusion coefficient maps were constructed for quantitative analysis. The regions of the treated uterine tissue were defined by a semisupervised segmentation method called the "eigenimage filter," using both cT1WI and DWI. Signal-to-noise ratios were determined for the T2WI pretreatment images. Segmented regions were tested by a similarity index for congruence. Descriptive, regression, and Bland-Altman statistics were calculated. RESULTS All the patients exhibited heterogeneously increased DWI signal intensity localized in the treated fibroid regions and were colocalized with the cT1WI defined area. The mean pretreatment T2WI signal intensity ratios were T2WI/muscle = 1.8 +/- 0.7 and T2WI/myometrium = 0.7 +/- 0.4. The congruence between the regions was significant, with a similarity of 84% and a difference of 8% between the regions. Regression analyses of the cT1WI and DWI segmented treatment volume were found to be significantly correlated (r2 = 0.94, p < 0.05) with the linear equation, (cT1WI) = 1.1 (DWI)-0.66. There is good agreement between the regions defined by cT1WI and DWI in most of the cases as shown from the Bland-Altman plots. CONCLUSIONS Diffusion-weighted imaging exhibited excellent agreement, congruence, and correlation with the cT1WI-defined region of treatment in uterine fibroid. Therefore, DWI could be useful as an adjunct for assessing treatment of uterine fibroids by MRg-HIFUS.
Collapse
Affiliation(s)
- Michael A Jacobs
- The Russell H. Morgan Department of Radiology and Radiological Science, Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University, School of Medicine, Baltimore, Maryland 21205, USA.
| | | | | |
Collapse
|
38
|
Ackerman JJH, Neil JJ. The use of MR-detectable reporter molecules and ions to evaluate diffusion in normal and ischemic brain. NMR IN BIOMEDICINE 2010; 23:725-33. [PMID: 20669147 PMCID: PMC3080095 DOI: 10.1002/nbm.1530] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
As a result of the technical challenges associated with distinguishing the MR signals arising from intracellular and extracellular water, a variety of endogenous and exogenous MR-detectable molecules and ions have been employed as compartment-specific reporters of water motion. Although these reporter molecules and ions do not have the same apparent diffusion coefficients (ADCs) as water, their ADCs are assumed to be directly related to the ADC of the water in which they are solvated. This approach has been used to probe motion in the intra- and extracellular space of cultured cells and intact tissue. Despite potential interpretative challenges with the use of reporter molecules or ions and the wide variety used, the following conclusions are consistent considering all studies: (i) the apparent free diffusive motion in the intracellular space is approximately one-half of that in dilute aqueous solution; (ii) ADCs for intracellular and extracellular water are similar; (iii) the intracellular ADC decreases in association with brain injury. These findings provide support for the hypothesis that the overall brain water ADC decrease that accompanies brain injury is driven primarily by a decrease in the ADC of intracellular water. We review the studies supporting these conclusions, and interpret them in the context of explaining the decrease in overall brain water ADC that accompanies brain injury.
Collapse
Affiliation(s)
- Joseph J H Ackerman
- Department of Chemistry, Campus Box 1134, Washington University School of Medicine, St. Louis, MO 63110, USA.
| | | |
Collapse
|
39
|
Lodygensky GA, West T, Stump M, Holtzman DM, Inder TE, Neil JJ. In vivo MRI analysis of an inflammatory injury in the developing brain. Brain Behav Immun 2010; 24:759-67. [PMID: 19945527 PMCID: PMC2885544 DOI: 10.1016/j.bbi.2009.11.005] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2009] [Revised: 11/13/2009] [Accepted: 11/15/2009] [Indexed: 11/30/2022] Open
Abstract
Cerebral periventricular white matter injury stands as a leading cause of cognitive, behavioral and motor impairment in preterm infants. There is epidemiological and histopathological evidence demonstrating the role of prenatal or neonatal inflammation in brain injury in preterm infants. In order to define the effect of an inflammatory insult in the developing brain on magnetic resonance (MR) imaging, we obtained high resolution conventional and diffusion MR images of the brain of rat pups after an inflammatory injury. Rat pups were subjected on postnatal day 5 (P5) to a stereotaxic injection of lipopolysaccharide in the corpus callosum and then imaged at 11.7 T on days 0, 2 and 4 following the injury. They were subsequently sacrificed for immunohistochemistry. Diffusion tensor imaging (DTI) acquired at high spatial resolution showed an initial reduction of the apparent diffusion coefficient (ADC) in the white matter. This was followed by an increase in ADC value and in T2 relaxation time constant in the white matter, with an associated increase of radial diffusivity of the corpus callosum, and a 10-fold increase in ventricular size. On histology, these MR changes corresponded to widespread astrogliosis, and decreased proportion of the section areas containing cresyl violet positive stain. The increase in radial diffusivity, typically attributed to myelin loss, occurred in this case despite the absence of myelin at this developmental stage.
Collapse
Affiliation(s)
- GA Lodygensky
- Department of the Child and Adolescent, Pediatric and Neonatal ICU, University of Geneva, Switzerland
,Departments of Pediatrics, Washington University, St Louis, Missouri, United States
| | - T West
- Department of Neurology and Developmental Biology, Washington University, St Louis, Missouri, United States
| | - M Stump
- Department of Neurology and Developmental Biology, Washington University, St Louis, Missouri, United States
| | - DM Holtzman
- Department of Neurology and Developmental Biology, Washington University, St Louis, Missouri, United States
,Hope Center for Neurological Disorders, Washington University, St Louis, Missouri, United States
| | - TE Inder
- Department of Neurology and Developmental Biology, Washington University, St Louis, Missouri, United States
,Departments of Radiology, Washington University, St Louis, Missouri, United States
,Departments of Pediatrics, Washington University, St Louis, Missouri, United States
| | - JJ Neil
- Department of Neurology and Developmental Biology, Washington University, St Louis, Missouri, United States
,Departments of Radiology, Washington University, St Louis, Missouri, United States
,Departments of Pediatrics, Washington University, St Louis, Missouri, United States
| |
Collapse
|
40
|
Abstract
Magnetic resonance imaging (MRI) has been shown to improve the diagnosis and management of patients with brain disorders. Multiparametric MRI offers the possibility of noninvasively assessing multiple facets of pathophysiological processes that exist simultaneously, thereby further assisting in patient treatment management. Voxel-based analysis approaches, such as tissue theme mapping, have the benefit over volumetric approaches in being able to identify spatially heterogeneous colocalized changes on multiple parametric MR images that are not readily discernible. Tissue theme maps seem to be a promising tool for integrating the plethora of novel imaging contrasts that are being developed for the noninvasive investigation of the different stages of disease progression into easily interpretable maps of brain injury. We describe here various implementations for combining multiparametric imaging and their merits in the evaluation of brain diseases.
Collapse
Affiliation(s)
- Ona Wu
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA 02129, USA.
| | | | | |
Collapse
|
41
|
Tamura H, Kurihara N, Machida Y, Nishino A, Shimosegawa E. How does water diffusion in human white matter change following ischemic stroke? Magn Reson Med Sci 2010; 8:121-34. [PMID: 19783875 DOI: 10.2463/mrms.8.121] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PURPOSE Temporal evolution of the water apparent diffusion coefficients (ADC) parallel (ADC parallel) and perpendicular (ADC perpendicular) to the human white matter tract following ischemia has not been investigated systematically. We attempted to quantify the evolution of ADC parallel and ADC perpendicular and examine whether it can be interpreted by a model of ischemic edema. METHODS We retrospectively selected 53 patients with ischemic lesions involving the posterior limb of the internal capsule (PLIC) and placed regions of interest in the right and left PLIC on ADC maps. We performed regression analysis of lesion-to-contralateral ratios of ADC parallel and ADC perpendicular against the time (t = 1-1600 h) from onset. We then fitted the estimated time courses of ADC parallel and ADC perpendicular obtained from the analysis to a model of nerve tissue composed of cylinders (axons) and spheres corresponding to isotropic structures, particularly focal cytoplasmic swellings of glial cells and axons seen in ischemic white matter. RESULTS The evolution of ADC perpendicular and ADC parallel differed. The estimated time course of ADC parallel in microm(2)*ms(-1) was 0.64 + 0.88 exp (-0.24t) for 1 < t < 54 h and 0.00059t + 0.61 for t >or= 54 h (contralateral normal value, 1.52). That of ADC perpendicular was 0.19-0.063 exp (-0.24t) for 1 < t < 54 h and 0.00040t + 0.17 for t >or=54 h (normal value 0.22). The model fitted to these values showed that the volume of the cylinders decreased, that of the spheres increased, and extracellular volume changed little from one hour to approximately one day after stroke onset. CONCLUSION In the human PLIC, ADC parallel continued to decrease from one hour to a few days after stroke onset, and ADC perpendicular tended to increase. The temporal evolution could be interpreted by progression of the focal cytoplasmic swelling of glial cells and axons previously observed in animal studies.
Collapse
Affiliation(s)
- Hajime Tamura
- Department of Noninvasive Diagnostic Imaging, Tohoku University Graduate School of Medicine, Aoba-ku, Sendai, Japan.
| | | | | | | | | |
Collapse
|
42
|
|
43
|
Cao Y, George KP, Ewing JR, Vikingstad EM, Johnson AF. Neuroimaging of language and aphasia after stroke. J Stroke Cerebrovasc Dis 2009; 7:230-3. [PMID: 17895089 DOI: 10.1016/s1052-3057(98)80031-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/1997] [Accepted: 01/08/1998] [Indexed: 01/27/2023] Open
Abstract
Over the past 25 years, neuroimaging techniques have advanced rapidly. These techniques, including computed tomography, magnetic resonance imaging, positron emission tomography and single photon emission computed tomography, have improved our understanding of the relationships of language, language disorder, and brain language organization. In this article, we review the contribution of these neuroimaging techniques to the fields of brain language function and speech-language disorders after ischemic stroke. We also discuss the future of these techniques in the research and clinical arenas of ischemic stroke and aphasia rehabilitation.
Collapse
Affiliation(s)
- Y Cao
- Department of Neurology, Henry Ford Health Sciences Center, Detroit, MI, USA
| | | | | | | | | |
Collapse
|
44
|
Jacobs MA, Pan L, Macura KJ. Whole-body diffusion-weighted and proton imaging: a review of this emerging technology for monitoring metastatic cancer. Semin Roentgenol 2009; 44:111-22. [PMID: 19233086 PMCID: PMC2955431 DOI: 10.1053/j.ro.2009.01.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Michael A Jacobs
- The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
| | | | | |
Collapse
|
45
|
|
46
|
Serduc R, van de Looij Y, Francony G, Verdonck O, van der Sanden B, Laissue J, Farion R, Bräuer-Krisch E, Siegbahn EA, Bravin A, Prezado Y, Segebarth C, Rémy C, Lahrech H. Characterization and quantification of cerebral edema induced by synchrotron x-ray microbeam radiation therapy. Phys Med Biol 2008; 53:1153-66. [DOI: 10.1088/0031-9155/53/5/001] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
47
|
Axer H, Grässel D, Brämer D, Fitzek S, Kaiser WA, Witte OW, Fitzek C. Time course of diffusion imaging in acute brainstem infarcts. J Magn Reson Imaging 2008; 26:905-12. [PMID: 17896361 DOI: 10.1002/jmri.21088] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
PURPOSE To study the time course of diffusion imaging at the lesion site in brainstem infarcts. MATERIALS AND METHODS Sequential MR scans were acquired from 24 patients with brainstem infarcts. Diffusion-weighted images (DWI), T(2)-weighted images (T(2)w), maps of apparent diffusion coefficient, and maps of fractional anisotropy were generated from each MR scan. A trend function was fitted to these measurements to model an objective, general time course of the studied parameters. RESULTS Apparent diffusion coefficient (ADC) continuously decreased over time until a transition time around 45 hours; afterwards a continuous increase took place. After the 14th day ADC reached values similar to the ADC of the intact contralateral side (pseudonormalization) and then further increased. Fractional anisotropy (FA) decreased continuously over 3 to 6 months. CONCLUSION Times of transition and pseudonormalization of ADC were longer than described for territorial hemispheric infarcts and describe the acute to subacute phase of brainstem ischemia. In contrast, the continuous decline of FA over 3 to 6 months indicates a chronic process of change of histological structures in brainstem ischemia, and may be regarded as an indicator of the chronic phase.
Collapse
Affiliation(s)
- Hubertus Axer
- Department of Neurology, Friedrich-Schiller-University Jena, Jena, Germany.
| | | | | | | | | | | | | |
Collapse
|
48
|
Gröhn O, Pitkänen A. Magnetic resonance imaging in animal models of epilepsy-noninvasive detection of structural alterations. Epilepsia 2007; 48 Suppl 4:3-10. [PMID: 17767570 DOI: 10.1111/j.1528-1167.2007.01236.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Small animal magnetic resonance imaging (MRI) has opened a window through which brain abnormalities can be observed over time in rodents noninvasively. We review MRI studies done during epileptogenesis triggered by status epilepticus in rat. Most of these studies have used quantitative T2, diffusion, and/or volumetric MRI. The goal has been to identify the distribution and severity of structural lesions during the epileptogenic process, that is, soon after status epilepticus, during epileptogenesis, and after the appearance of spontaneous seizures. Data obtained demonstrate that MRI can be used to associate the development of brain pathology with the evolution of clinical phenotype. MRI can also be used to select animals to preclinical studies based on the severity and/or distribution of brain damage, thus making the study population more homogeneous, for example, for assessment of novel antiepileptogenic or neuroprotective treatments. Importantly, follow-up data collected emphasize interindividual differences in the dynamics of development of abnormalities that could have remained undetected in a typical histologic analysis providing a snapshot to brain pathology. A great future challenge is to take advantage of interanimal variability in MRI in the development of surrogate markers for epilepsy or its comorbidities such as memory impairment. Understanding of molecular and cellular mechanisms underlying changes in various MRI techniques will help to better understand complex progressive pathological processes associated with epileptogenesis and epilepsy.
Collapse
Affiliation(s)
- Olli Gröhn
- Biomedical NMR Research Group, Department of Neurobiology, A.I. Virtanen Institute for Molecular Sciences, University of Kuopio, Kuopio, Finland.
| | | |
Collapse
|
49
|
Affiliation(s)
- Jeffrey J Neil
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri, USA.
| |
Collapse
|
50
|
Wu O, Sumii T, Asahi M, Sasamata M, Ostergaard L, Rosen BR, Lo EH, Dijkhuizen RM. Infarct prediction and treatment assessment with MRI-based algorithms in experimental stroke models. J Cereb Blood Flow Metab 2007; 27:196-204. [PMID: 16685257 DOI: 10.1038/sj.jcbfm.9600328] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
There is increasing interest in using algorithms combining multiple magnetic resonance imaging (MRI) modalities to predict tissue infarction in acute human stroke. We developed and tested a voxel-based generalized linear model (GLM) algorithm to predict tissue infarction in an animal stroke model in order to directly compare predicted outcome with the tissue's histologic outcome, and to evaluate the potential for assessing therapeutic efficacy using these multiparametric algorithms. With acute MRI acquired after unilateral embolic stroke in rats (n=8), a GLM was developed and used to predict infarction on a voxel-wise basis for saline (n=6) and recombinant tissue plasminogen activator (rt-PA) treatment (n=7) arms of a trial of delayed thrombolytic therapy in rats. Pretreatment predicted outcome compared with post-treatment histology was highly accurate in saline-treated rats (0.92+/-0.05). Accuracy was significantly reduced (P=0.04) in rt-PA-treated animals (0.86+/-0.08), although no significant difference was detected when comparing histologic lesion volumes. Animals that reperfused had significantly lower (P<0.01) GLM-predicted infarction risk (0.73+/-0.03) than nonreperfused animals (0.81+/-0.05), possibly reflecting less severe initial ischemic injury and therefore tissue likely more amenable to therapy. Our results show that acute MRI-based algorithms can predict tissue infarction with high accuracy in animals not receiving thrombolytic therapy. Furthermore, alterations in disease progression due to treatment were more sensitively monitored with our voxel-based analysis techniques than with volumetric approaches. Our study shows that predictive algorithms are promising metrics for diagnosis, prognosis and therapeutic evaluation after acute stroke that can translate readily from preclinical to clinical settings.
Collapse
Affiliation(s)
- Ona Wu
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands.
| | | | | | | | | | | | | | | |
Collapse
|