301
|
Liu C, Wei H, Gong NJ, Cronin M, Dibb R, Decker K. Quantitative Susceptibility Mapping: Contrast Mechanisms and Clinical Applications. ACTA ACUST UNITED AC 2015; 1:3-17. [PMID: 26844301 PMCID: PMC4734903 DOI: 10.18383/j.tom.2015.00136] [Citation(s) in RCA: 122] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Quantitative susceptibility mapping (QSM) is a recently developed magnetic resonance imaging (MRI) technique for quantifying the spatial distribution of magnetic susceptibility within biological tissues. It first uses the frequency shift in the MRI signal to map the magnetic field profile within the tissue. The resulting field map is then used to determine the spatial distribution of the underlying magnetic susceptibility by solving an inverse problem. The solution is achieved by deconvolving the field map with a dipole field, under the assumption that the magnetic field results from a superposition of the dipole fields generated by all voxels and that each voxel has its own unique magnetic susceptibility. QSM provides an improved contrast-to-noise ratio for certain tissues and structures compared with its magnitude counterpart. More importantly, magnetic susceptibility directly reflects the molecular composition and cellular architecture of the tissue. Consequently, by quantifying magnetic susceptibility, QSM is becoming a quantitative imaging approach for characterizing normal and pathological tissue properties. This article reviews the mechanism that generates susceptibility contrast within tissues and some associated applications.
Collapse
Affiliation(s)
- Chunlei Liu
- Brain Imaging and Analysis Center, Duke University School of Medicine, Durham, NC 27710; Department of Radiology, Duke University School of Medicine, Durham, NC 27710; Center for In Vivo Microscopy, Duke University School of Medicine, Durham, NC 27710
| | - Hongjiang Wei
- Brain Imaging and Analysis Center, Duke University School of Medicine, Durham, NC 27710
| | - Nan-Jie Gong
- Brain Imaging and Analysis Center, Duke University School of Medicine, Durham, NC 27710
| | - Matthew Cronin
- Brain Imaging and Analysis Center, Duke University School of Medicine, Durham, NC 27710
| | - Russel Dibb
- Center for In Vivo Microscopy, Duke University School of Medicine, Durham, NC 27710
| | - Kyle Decker
- Center for In Vivo Microscopy, Duke University School of Medicine, Durham, NC 27710
| |
Collapse
|
302
|
Gho SM, Shin J, Kim MO, Kim DH. Simultaneous quantitative mapping of conductivity and susceptibility using a double-echo ultrashort echo time sequence: Example using a hematoma evolution study. Magn Reson Med 2015; 76:214-21. [DOI: 10.1002/mrm.25869] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 06/23/2015] [Accepted: 07/14/2015] [Indexed: 11/09/2022]
Affiliation(s)
- Sung-Min Gho
- Department of Electrical and Electronic Engineering; Institute of BioMed-IT, Energy-IT and Smart-IT Technology, Yonsei University; Seoul Republic of Korea
| | - Jaewook Shin
- Department of Electrical and Electronic Engineering; Yonsei University; Seoul Republic of Korea
| | - Min-Oh Kim
- Department of Electrical and Electronic Engineering; Yonsei University; Seoul Republic of Korea
| | - Dong-Hyun Kim
- Department of Electrical and Electronic Engineering; Yonsei University; Seoul Republic of Korea
| |
Collapse
|
303
|
Appraising the Role of Iron in Brain Aging and Cognition: Promises and Limitations of MRI Methods. Neuropsychol Rev 2015; 25:272-87. [PMID: 26248580 DOI: 10.1007/s11065-015-9292-y] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 07/24/2015] [Indexed: 12/11/2022]
Abstract
Age-related increase in frailty is accompanied by a fundamental shift in cellular iron homeostasis. By promoting oxidative stress, the intracellular accumulation of non-heme iron outside of binding complexes contributes to chronic inflammation and interferes with normal brain metabolism. In the absence of direct non-invasive biomarkers of brain oxidative stress, iron accumulation estimated in vivo may serve as its proxy indicator. Hence, developing reliable in vivo measurements of brain iron content via magnetic resonance imaging (MRI) is of significant interest in human neuroscience. To date, by estimating brain iron content through various MRI methods, significant age differences and age-related increases in iron content of the basal ganglia have been revealed across multiple samples. Less consistent are the findings that pertain to the relationship between elevated brain iron content and systemic indices of vascular and metabolic dysfunction. Only a handful of cross-sectional investigations have linked high iron content in various brain regions and poor performance on assorted cognitive tests. The even fewer longitudinal studies indicate that iron accumulation may precede shrinkage of the basal ganglia and thus predict poor maintenance of cognitive functions. This rapidly developing field will benefit from introduction of higher-field MRI scanners, improvement in iron-sensitive and -specific acquisition sequences and post-processing analytic and computational methods, as well as accumulation of data from long-term longitudinal investigations. This review describes the potential advantages and promises of MRI-based assessment of brain iron, summarizes recent findings and highlights the limitations of the current methodology.
Collapse
|
304
|
He N, Ling H, Ding B, Huang J, Zhang Y, Zhang Z, Liu C, Chen K, Yan F. Region-specific disturbed iron distribution in early idiopathic Parkinson's disease measured by quantitative susceptibility mapping. Hum Brain Mapp 2015; 36:4407-20. [PMID: 26249218 DOI: 10.1002/hbm.22928] [Citation(s) in RCA: 159] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Revised: 07/13/2015] [Accepted: 07/23/2015] [Indexed: 02/06/2023] Open
Abstract
In Parkinson's disease (PD), iron elevation in specific brain regions as well as selective loss of dopaminergic neurons is a major pathologic feature. A reliable quantitative measure of iron deposition is a potential biomarker for PD and may contribute to the investigation of iron-mediated PD. The primary purpose of this study is to assess iron variations in multiple deep grey matter nuclei in early PD with a novel MRI technique, quantitative susceptibility mapping (QSM). The inter-group differences of susceptibility and R2* value in deep grey matter nuclei, namely head of caudate nucleus (CN), putamen (PUT), global pallidus (GP), substantia nigra (SN), and red nucleus (RN), and the correlations between regional iron deposition and the clinical features were explored in forty-four early PD patients and 35 gender and age-matched healthy controls. Susceptibility values were found to be elevated within bilateral SN and RN contralateral to the most affected limb in early PD compared with healthy controls (HCs). The finding of increased susceptibility in bilateral SN is consistent with work on a subgroup of patients at the earliest clinical detectable state (Hoehn and Yahr [1967]: Neurology 17:427-442; Stage I). However, increased R2* values were only seen within SN contralateral to the most affected limb in the PD group when compared with controls. Furthermore, bilateral SN magnetic susceptibility positively correlated with disease duration and UPDRS-III scores in early PD. This finding supports the potential value of QSM as a non-invasive quantitative biomarker of early PD.
Collapse
Affiliation(s)
- Naying He
- Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Huawei Ling
- Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Bei Ding
- Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Juan Huang
- Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yong Zhang
- MR Research, GE Healthcare, Shanghai, China
| | | | - Chunlei Liu
- Brain Imaging and Analysis Center, Duke University Medical Center, Durham, North Carolina.,Department of Radiology, Duke University Medical Center, Durham, North Carolina
| | - Kemin Chen
- Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Fuhua Yan
- Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| |
Collapse
|
305
|
|
306
|
Quantitative susceptibility mapping in patients with systemic lupus erythematosus: detection of abnormalities in normal-appearing basal ganglia. Eur Radiol 2015; 26:1056-63. [DOI: 10.1007/s00330-015-3929-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 06/25/2015] [Accepted: 07/13/2015] [Indexed: 01/08/2023]
|
307
|
Moon HJ, Chang Y, Lee YS, Song H, Chang HW, Ku J, Allen RP, Earley CJ, Cho YW. A comparison of MRI tissue relaxometry and ROI methods used to determine regional brain iron concentrations in restless legs syndrome. MEDICAL DEVICES-EVIDENCE AND RESEARCH 2015; 8:341-50. [PMID: 26257527 PMCID: PMC4525804 DOI: 10.2147/mder.s83629] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Purpose Magnetic resonance imaging relaxometry studies differed on the relaxometry methods and their approaches to determining the regions of interest (ROIs) in restless legs syndrome (RLS) patients. These differences could account for the variable and inconsistent results found across these studies. The aim of this study was to assess the relationship between the different relaxometry methods and different ROI approaches using each of these methods on a single population of controls and RLS subjects. Methods A 3.0-T magnetic resonance imaging with the gradient-echo sampling of free induction decay and echo pulse sequence was used. The regional brain “iron concentrations” were determined using three relaxometry metrics (R2, R2*, and R2′) through two different ROI methods. The substantia nigra (SN) was the primary ROI with red nucleus, caudate, putamen, and globus pallidus as the secondary ROIs. Results Thirty-seven RLS patients and 40 controls were enrolled. The iron concentration as determined by R2 did not correlate with either of the other two methods, while R2* and R2′ showed strong correlations, particularly for the substantia nigra and red nucleus. In the fixed-shape ROI method, the RLS group showed a lower iron index compared to the control group in the substantia nigra and several other regions. With the semi-automated ROI method, however, only the red nucleus showed a significant difference between the two groups. Conclusion Both the relaxometry and ROI determination methods significantly influenced the outcome of studies that used these methods to estimate regional brain iron concentrations.
Collapse
Affiliation(s)
- Hye-Jin Moon
- Department of Neurology, Dongsan Medical Center, Keimyung University School of Medicine, Daegu, Republic of Korea
| | - Yongmin Chang
- Department of Molecular Medicine, Kyungpook National University and Hospital, Daegu, Republic of Korea
| | - Yeong Seon Lee
- Department of Neurology, Dongsan Medical Center, Keimyung University School of Medicine, Daegu, Republic of Korea
| | - Huijin Song
- Department of Medical and Biological Engineering, Kyungpook National University and Hospital, Daegu, Republic of Korea
| | - Hyuk Won Chang
- Department of Radiology, Keimyung University, Daegu, Republic of Korea
| | - Jeonghun Ku
- Department of Biomedical Engineering, School of Medicine, Keimyung University, Daegu, Republic of Korea
| | - Richard P Allen
- Department of Neurology, Johns Hopkins University, Hopkins Bayview Medical Center, Baltimore, MD, USA
| | - Christopher J Earley
- Department of Neurology, Johns Hopkins University, Hopkins Bayview Medical Center, Baltimore, MD, USA
| | - Yong Won Cho
- Department of Neurology, Dongsan Medical Center, Keimyung University School of Medicine, Daegu, Republic of Korea
| |
Collapse
|
308
|
Persson N, Wu J, Zhang Q, Liu T, Shen J, Bao R, Ni M, Liu T, Wang Y, Spincemaille P. Age and sex related differences in subcortical brain iron concentrations among healthy adults. Neuroimage 2015. [PMID: 26216277 DOI: 10.1016/j.neuroimage.2015.07.050] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Age and sex can influence brain iron levels. We studied the influence of these variables on deep gray matter magnetic susceptibilities. In 183 healthy volunteers (44.7 ± 14.2 years, range 20-69, ♀ 49%), in vivo quantitative susceptibility mapping (QSM) at 1.5T was performed to estimate brain iron accumulation in the following regions of interest (ROIs): caudate nucleus (Cd), putamen (Pt), globus pallidus (Gp), thalamus (Th), pulvinar (Pul), red nucleus (Rn), substantia nigra (Sn) and the cerebellar dentate nuclei (Dn). We gauged the influence of age and sex on magnetic susceptibility by specifying a series of structural equation models. The distributions of susceptibility varied in degree across the structures, conforming to histologic findings (Hallgren and Sourander, 1958), with the highest degree of susceptibility in the Gp and the lowest in the Th. Iron increase correlated across several ROIs, which may reflect an underlying age-related process. Advanced age was associated with a particularly strong linear rise of susceptibility in the striatum. Nonlinear age trends were found in the Rn, where they were the most pronounced, followed by the Pul and Sn, while minimal nonlinear trends were observed for the Pt, Th, and Dn. Moreover, sex related variations were observed, so that women showed lower levels of susceptibility in the Sn after accounting for age. Regional susceptibility of the Pul increased linearly with age in men but exhibited a nonlinear association with age in women with a leveling off starting from midlife. Women expected to be post menopause (+51 years) showed lower total magnetic susceptibility in the subcortical gray matter. The current report not only is consistent with previous reports of age related variations of brain iron, but also adds to the current knowledge by reporting age-related changes in less studied, smaller subcortical nuclei. This is the first in-vivo report to show lower total subcortical brain iron levels selectively in women from midlife, compared to men and younger women. These results encourage further assessment of sex differences in brain iron. We anticipate that age and sex are important co-factors to take into account when establishing a baseline level for differentiating pathologic neurodegeneration from healthy aging. The variations in regional susceptibility reported herein should be evaluated further using a longitudinal study design to determine within-person changes in aging.
Collapse
Affiliation(s)
- Ninni Persson
- Department of Psychology, Stockholm University, Stockholm, Sweden; Stockholm Brain Institute, Stockholm, Sweden; Radiology, Weill Cornell Medical College, New York, NY, USA
| | - Jianlin Wu
- Radiology, The 1st Hospital of Dalian Medical University, Dalian, Liaoning Province, China; Radiology, Zhongshan Hospital of Dalian University, Dalian, Liaoning Province, China
| | - Qing Zhang
- Radiology, The 1st Hospital of Dalian Medical University, Dalian, Liaoning Province, China
| | - Ting Liu
- Radiology, The 1st Hospital of Dalian Medical University, Dalian, Liaoning Province, China
| | - Jing Shen
- Radiology, The 1st Hospital of Dalian Medical University, Dalian, Liaoning Province, China
| | - Ruyi Bao
- Radiology, The 1st Hospital of Dalian Medical University, Dalian, Liaoning Province, China
| | - Mingfei Ni
- Radiology, The 1st Hospital of Dalian Medical University, Dalian, Liaoning Province, China
| | - Tian Liu
- Radiology, Weill Cornell Medical College, New York, NY, USA
| | - Yi Wang
- Radiology, Weill Cornell Medical College, New York, NY, USA; Biomedical Engineering, Cornell University, Ithaca, NY, USA
| | | |
Collapse
|
309
|
Abstract
Increased brain iron content has been linked to neural degeneration and to age-related decline of cognitive and motor functions. The basal ganglia (BG), which contain significant amount of iron, play an important role in establishing and modulating force requirements in hand grasp to meet specific task demands. However, it is unclear if increased BG iron content contributes to age differences in hand grasp performance. To investigate the relationship between BG iron content and hand grasp force matching in older (65.0 ± 8.9 years) healthy women, participants generated a 20% maximum voluntary exertion reference force that was matched with the opposite hand in the Contralateral Remembered (CR) and Contralateral Concurrent (CC) conditions and with the same hand in the Ipsilateral Remembered (IR) condition. T2* relaxation times calculated from MRI scans served to estimate iron content in the caudate nucleus (Cd), globus pallidus (GP), and putamen (Pt). Greater iron content in all BG was associated with relatively greater number of errors committed when matching force with the opposite hand in the CR and CC conditions than with the same hand in the IR condition. Younger women with greater estimated iron content committed more errors than their older counterparts with lesser estimated iron content in Cd and Pt. Greater iron content in the BG may contribute to sensorimotor declines in healthy women, and relative iron content quantified by MRI may be a promising biomarker of such.
Collapse
|
310
|
Elekofehinti OO, Kamdem JP, Meinerz DF, Kade IJ, Adanlawo IG, Rocha JBT. Saponin from the fruit of Solanum anguivi protects against oxidative damage mediated by Fe 2+ and sodium nitroprusside in rat brain synaptosome P2 fraction. Arch Pharm Res 2015. [PMID: 26160066 DOI: 10.1007/s12272-014-0536-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 12/20/2014] [Indexed: 10/23/2022]
Abstract
Solanum anguivi fruit saponin has antidiabetic property via interference with cellular energy metabolism and inhibition of reactive oxygen species (ROS) generation. In the current study, brain specific in vitro anti-oxidant role of S. anguivi saponin was investigated in the P2 synaptosomal fraction of rat brain. Using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction assay, S. anguivi saponin concentration- dependently (10-200 µg/ml) reversed Fe2+ and sodium nitroprusside- induced decrease in mitochondrial activity via inhibition of ROS production, ROS-induced oxidation of protein and non-protein thiol-containing molecules and lipid peroxidation as measured by thiobarbituric acid reactive substances levels. Conclusively, S. anguivi fruit saponin represents a class of natural compounds with the ability to reverse synaptosomal disruption, loss of mitochondrial integrity and function often associated with the progression of Huntington's disease, Alzheimer disease, Parkinson disease and amyotrophic lateral sclerosis diseases.
Collapse
|
311
|
MacDonald ME, Frayne R. Cerebrovascular MRI: a review of state-of-the-art approaches, methods and techniques. NMR IN BIOMEDICINE 2015; 28:767-791. [PMID: 26010775 DOI: 10.1002/nbm.3322] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 04/08/2015] [Accepted: 04/09/2015] [Indexed: 06/04/2023]
Abstract
Cerebrovascular imaging is of great interest in the understanding of neurological disease. MRI is a non-invasive technology that can visualize and provide information on: (i) the structure of major blood vessels; (ii) the blood flow velocity in these vessels; and (iii) the microcirculation, including the assessment of brain perfusion. Although other medical imaging modalities can also interrogate the cerebrovascular system, MR provides a comprehensive assessment, as it can acquire many different structural and functional image contrasts whilst maintaining a high level of patient comfort and acceptance. The extent of examination is limited only by the practicalities of patient tolerance or clinical scheduling limitations. Currently, MRI methods can provide a range of metrics related to the cerebral vasculature, including: (i) major vessel anatomy via time-of-flight and contrast-enhanced imaging; (ii) blood flow velocity via phase contrast imaging; (iii) major vessel anatomy and tissue perfusion via arterial spin labeling and dynamic bolus passage approaches; and (iv) venography via susceptibility-based imaging. When designing an MRI protocol for patients with suspected cerebral vascular abnormalities, it is appropriate to have a complete understanding of when to use each of the available techniques in the 'MR angiography toolkit'. In this review article, we: (i) overview the relevant anatomy, common pathologies and alternative imaging modalities; (ii) describe the physical principles and implementations of the above listed methods; (iii) provide guidance on the selection of acquisition parameters; and (iv) describe the existing and potential applications of MRI to the cerebral vasculature and diseases. The focus of this review is on obtaining an understanding through the application of advanced MRI methodology of both normal and abnormal blood flow in the cerebrovascular arteries, capillaries and veins.
Collapse
Affiliation(s)
- Matthew Ethan MacDonald
- Biomedical Engineering, Radiology, and Clinical Neuroscience, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Richard Frayne
- Biomedical Engineering, Radiology, and Clinical Neuroscience, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| |
Collapse
|
312
|
Hare DJ, Arora M, Jenkins NL, Finkelstein DI, Doble PA, Bush AI. Is early-life iron exposure critical in neurodegeneration? Nat Rev Neurol 2015; 11:536-44. [DOI: 10.1038/nrneurol.2015.100] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
313
|
Yarnykh VL. Time-efficient, high-resolution, whole brain three-dimensional macromolecular proton fraction mapping. Magn Reson Med 2015; 75:2100-6. [PMID: 26102097 DOI: 10.1002/mrm.25811] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 05/23/2015] [Accepted: 05/24/2015] [Indexed: 12/19/2022]
Abstract
PURPOSE Macromolecular proton fraction (MPF) mapping is a quantitative MRI method that reconstructs parametric maps of a relative amount of macromolecular protons causing the magnetization transfer (MT) effect and provides a biomarker of myelination in neural tissues. This study aimed to develop a high-resolution whole brain MPF mapping technique using a minimal number of source images for scan time reduction. METHODS The described technique was based on replacement of an actually acquired reference image without MT saturation by a synthetic one reconstructed from R1 and proton density maps, thus requiring only three source images. This approach enabled whole brain three-dimensional MPF mapping with isotropic 1.25 × 1.25 × 1.25 mm(3) voxel size and a scan time of 20 min. The synthetic reference method was validated against standard MPF mapping with acquired reference images based on data from eight healthy subjects. RESULTS Mean MPF values in segmented white and gray matter appeared in close agreement with no significant bias and small within-subject coefficients of variation (<2%). High-resolution MPF maps demonstrated sharp white-gray matter contrast and clear visualization of anatomical details, including gray matter structures with high iron content. CONCLUSIONS The proposed synthetic reference method improves resolution of MPF mapping and combines accurate MPF measurements with unique neuroanatomical contrast features.
Collapse
Affiliation(s)
- Vasily L Yarnykh
- Department of Radiology, University of Washington, Seattle, Washington, USA.,Research Institute of Biology and Biophysics, Tomsk State University, Tomsk, Russian Federation
| |
Collapse
|
314
|
Cobzas D, Sun H, Walsh AJ, Lebel RM, Blevins G, Wilman AH. Subcortical gray matter segmentation and voxel-based analysis using transverse relaxation and quantitative susceptibility mapping with application to multiple sclerosis. J Magn Reson Imaging 2015; 42:1601-10. [DOI: 10.1002/jmri.24951] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 05/01/2015] [Indexed: 11/10/2022] Open
Affiliation(s)
- Dana Cobzas
- Biomedical Engineering; University of Alberta; Edmonton Canada
- Computing Science; University of Alberta; Edmonton Canada
| | - Hongfu Sun
- Biomedical Engineering; University of Alberta; Edmonton Canada
| | - Andrew J. Walsh
- Biomedical Engineering; University of Alberta; Edmonton Canada
| | - R. Marc Lebel
- Biomedical Engineering; University of Alberta; Edmonton Canada
| | - Gregg Blevins
- Division of Neurology; University of Alberta; Edmonton Canada
| | - Alan H. Wilman
- Biomedical Engineering; University of Alberta; Edmonton Canada
| |
Collapse
|
315
|
Langley J, Huddleston DE, Chen X, Sedlacik J, Zachariah N, Hu X. A multicontrast approach for comprehensive imaging of substantia nigra. Neuroimage 2015; 112:7-13. [PMID: 25731994 PMCID: PMC4415274 DOI: 10.1016/j.neuroimage.2015.02.045] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 01/10/2015] [Accepted: 02/19/2015] [Indexed: 01/22/2023] Open
Abstract
We characterize the contrast behavior of substantia nigra (SN) in both magnetization transfer (MT) imaging, which is believed to be sensitive to neuromelanin (NM), and susceptibility weighted imaging (SWI). Images were acquired with a MT prepared dual echo gradient echo sequence. The first echo was taken as the MT contrast image and the second was used to generate the SWI image. SN volumes were segmented from these two types of images using a thresholding method. The spatial and signal characteristics of the extracted SWI and MT volumes were compared. Both images showed the presence of SN but the volumes of the SN identified in the two are spatially incongruent. The MT volume was more caudal than the SWI volume and with only a 12% overlap between the two volumes. Considering the SN volumes in each hemisphere separately, the average distances between the centers of mass of the volumes from the two types images are 5.1±1.1mm and 4.1±1.2mm, respectively. The frequency offsets (homodyne filtered phase/echo time) for the volumes derived from MT (NM) images and SWI images are 0.09±0.32radians/s and -1.12±0.57radians/s (p<0.0001), respectively. The MT contrasts for the two volumes are 0.16±0.02 and 0.10±0.03 (p<0.001), respectively. Our results indicate that the two contrasts are sensitive to different portions of the SN, with MT seeing the more caudal portion of the SN than SWI, likely due to variations of NM and iron content in the SN. Despite the small overlap, these regions are complementary. Our results provide a new understanding of the contrast behavior of the SN in the two imaging approaches commonly used to image it and indicate that using both may yield a more comprehensive visualization of the SN.
Collapse
Affiliation(s)
- Jason Langley
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, United States
| | - Daniel E Huddleston
- Department of Neurology, Emory University, Atlanta, GA, United States; Center for Health Research Southeast, Kaiser Permanente, Atlanta, GA, United States
| | - Xiangchuan Chen
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, United States
| | - Jan Sedlacik
- Department of Neuroradiology, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Nishant Zachariah
- Department of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA, United States
| | - Xiaoping Hu
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, United States.
| |
Collapse
|
316
|
Nonlinear magnitude and linear phase behaviors of T2* imaging: theoretical approximation and Monte Carlo simulation. Magn Reson Imaging 2015; 33:390-400. [DOI: 10.1016/j.mri.2015.01.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 01/14/2015] [Accepted: 01/18/2015] [Indexed: 11/24/2022]
|
317
|
James SA, Roberts BR, Hare DJ, de Jonge MD, Birchall IE, Jenkins NL, Cherny RA, Bush AI, McColl G. Direct in vivo imaging of ferrous iron dyshomeostasis in ageing Caenorhabditis elegans. Chem Sci 2015; 6:2952-2962. [PMID: 28706676 PMCID: PMC5490054 DOI: 10.1039/c5sc00233h] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 03/03/2015] [Indexed: 01/09/2023] Open
Abstract
Iron is essential for eukaryotic biochemistry. Systematic trafficking and storage is required to maintain supply of iron while preventing it from catalysing unwanted reactions, particularly the generation of oxidising reactive species. Iron dyshomeostasis has been implicated in major age-associated diseases including cancers, neurodegeneration and heart disease. Here, we employ population-level X-ray fluorescence imaging and native-metalloproteomic analysis to determine that altered iron coordination and distribution is a pathological imperative of ageing in the nematode, Caenorhabditis elegans. Our approach provides a method to simultaneously study iron metabolism across different scales of biological organisation, from populations to cells. Here we report how and where iron homeostasis is lost during C. elegans ageing, and its relationship to the age-related elevation of damaging reactive oxygen species. We find that wild types utilise ferritin to sustain longevity, buffering against exogenous iron and showing rapid ageing if ferritin is ablated. After reproduction, escape of iron from safe-storage in ferritin raised cellular Fe2+ load in the ageing C. elegans, and increased generation of reactive species. These findings support the hypothesis that iron-mediated processes drive senescence. We propose that loss of iron homeostasis may be a fundamental and inescapable consequence of ageing that could represent a critical target for therapeutic strategies to improve health outcomes in ageing.
Collapse
Affiliation(s)
- Simon A James
- Australian Synchrotron , Clayton , Victoria , Australia
- Commonwealth Scientific and Industrial Research Organisation , Clayton , Victoria , Australia
- The Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Kenneth Myer Building, 30 Royal Parade , Parkville , Victoria , Australia 3052 . ; ; Tel: +61 3 9035 6608
| | - Blaine R Roberts
- The Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Kenneth Myer Building, 30 Royal Parade , Parkville , Victoria , Australia 3052 . ; ; Tel: +61 3 9035 6608
| | - Dominic J Hare
- The Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Kenneth Myer Building, 30 Royal Parade , Parkville , Victoria , Australia 3052 . ; ; Tel: +61 3 9035 6608
- Elemental Bio-imaging Facility , University of Technology Sydney , Broadway , New South Wales , Australia
- Exposure Biology Laboratory , Lautenberg Environment Health Sciences Laboratory , Department of Preventive Medicine , Icahn School of Medicine at Mount Sinai , New York , New York , USA
| | | | - Ian E Birchall
- The Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Kenneth Myer Building, 30 Royal Parade , Parkville , Victoria , Australia 3052 . ; ; Tel: +61 3 9035 6608
| | - Nicole L Jenkins
- The Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Kenneth Myer Building, 30 Royal Parade , Parkville , Victoria , Australia 3052 . ; ; Tel: +61 3 9035 6608
| | - Robert A Cherny
- The Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Kenneth Myer Building, 30 Royal Parade , Parkville , Victoria , Australia 3052 . ; ; Tel: +61 3 9035 6608
| | - Ashley I Bush
- The Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Kenneth Myer Building, 30 Royal Parade , Parkville , Victoria , Australia 3052 . ; ; Tel: +61 3 9035 6608
| | - Gawain McColl
- The Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Kenneth Myer Building, 30 Royal Parade , Parkville , Victoria , Australia 3052 . ; ; Tel: +61 3 9035 6608
| |
Collapse
|
318
|
Chai C, Yan S, Chu Z, Wang T, Wang L, Zhang M, Zuo C, Haacke EM, Xia S, Shen W. Quantitative measurement of brain iron deposition in patients with haemodialysis using susceptibility mapping. Metab Brain Dis 2015; 30:563-71. [PMID: 25182196 DOI: 10.1007/s11011-014-9608-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Accepted: 08/12/2014] [Indexed: 10/24/2022]
Abstract
To compare the susceptibility of different brain structures in patients with haemodialysis with that in healthy controls using susceptibility mapping and explore the correlations with neuropsychiatric tests and clinical parameters. Fifty three patients with haemodialysis and forty-five age-and sex-matched healthy controls were recruited in this prospective study. Susceptibility maps (SM) were reconstructed from original phase data and used to compare the susceptibility of different brain structures between patients and healthy controls. The SM was compared with iron predictions from a classic cadaver brain study. Spearman's correlation and stepwise multiple regression analysis between susceptibility and neuropsychiatric tests and clinical parameters were calculated. In patients with haemodialysis, the susceptibility of the bilateral caudate head, putamen, substantia nigra, red nucleus and dentate nucleus were significantly higher than those in healthy controls (P < 0.01). There was positive correlation between susceptibility both from normal controls and patients and iron concentration from a classic post-mortem brain study (both r = 0.900, both P = 0.037). In patients with haemodialysis, the susceptibility of the left putamen (r = 0.944), right putamen (r = 0.882) and right thalamus (r = 0.852) were correlated to dialysis duration (all P < 0.05). The susceptibility of the left caudate head (r = -0.415) and right caudate head (r = -0.311) were mildly negatively correlated with neuropsychiatric test scores (all P < 0.05). In summary, our findings indicated that increased brain iron deposition does occur in patients with haemodialysis and correlated with duration of dialysis.
Collapse
Affiliation(s)
- Chao Chai
- Department of Medical Imaging, Tianjin First Central Hospital, Tianjin, 300192, China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
319
|
Murakami Y, Kakeda S, Watanabe K, Ueda I, Ogasawara A, Moriya J, Ide S, Futatsuya K, Sato T, Okada K, Uozumi T, Tsuji S, Liu T, Wang Y, Korogi Y. Usefulness of quantitative susceptibility mapping for the diagnosis of Parkinson disease. AJNR Am J Neuroradiol 2015; 36:1102-8. [PMID: 25767187 DOI: 10.3174/ajnr.a4260] [Citation(s) in RCA: 123] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 11/24/2014] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Quantitative susceptibility mapping allows overcoming several nonlocal restrictions of susceptibility-weighted and phase imaging and enables quantification of magnetic susceptibility. We compared the diagnostic accuracy of quantitative susceptibility mapping and R2* (1/T2*) mapping to discriminate between patients with Parkinson disease and controls. MATERIALS AND METHODS For 21 patients with Parkinson disease and 21 age- and sex-matched controls, 2 radiologists measured the quantitative susceptibility mapping values and R2* values in 6 brain structures (the thalamus, putamen, caudate nucleus, pallidum, substantia nigra, and red nucleus). RESULTS The quantitative susceptibility mapping values and R2* values of the substantia nigra were significantly higher in patients with Parkinson disease (P < .01); measurements in other brain regions did not differ significantly between patients and controls. For the discrimination of patients with Parkinson disease from controls, receiver operating characteristic analysis suggested that the optimal cutoff values for the substantia nigra, based on the Youden Index, were >0.210 for quantitative susceptibility mapping and >28.8 for R2*. The sensitivity, specificity, and accuracy of quantitative susceptibility mapping were 90% (19 of 21), 86% (18 of 21), and 88% (37 of 42), respectively; for R2* mapping, they were 81% (17 of 21), 52% (11 of 21), and 67% (28 of 42). Pair-wise comparisons showed that the areas under the receiver operating characteristic curves were significantly larger for quantitative susceptibility mapping than for R2* mapping (0.91 versus 0.69, P < .05). CONCLUSIONS Quantitative susceptibility mapping showed higher diagnostic performance than R2* mapping for the discrimination between patients with Parkinson disease and controls.
Collapse
Affiliation(s)
- Y Murakami
- From the Departments of Radiology (Y.M., S.K., K.W., I.U., A.O., J.M., S.I., K.F., T.S., Y.K.)
| | - S Kakeda
- From the Departments of Radiology (Y.M., S.K., K.W., I.U., A.O., J.M., S.I., K.F., T.S., Y.K.)
| | - K Watanabe
- From the Departments of Radiology (Y.M., S.K., K.W., I.U., A.O., J.M., S.I., K.F., T.S., Y.K.)
| | - I Ueda
- From the Departments of Radiology (Y.M., S.K., K.W., I.U., A.O., J.M., S.I., K.F., T.S., Y.K.)
| | - A Ogasawara
- From the Departments of Radiology (Y.M., S.K., K.W., I.U., A.O., J.M., S.I., K.F., T.S., Y.K.)
| | - J Moriya
- From the Departments of Radiology (Y.M., S.K., K.W., I.U., A.O., J.M., S.I., K.F., T.S., Y.K.)
| | - S Ide
- From the Departments of Radiology (Y.M., S.K., K.W., I.U., A.O., J.M., S.I., K.F., T.S., Y.K.)
| | - K Futatsuya
- From the Departments of Radiology (Y.M., S.K., K.W., I.U., A.O., J.M., S.I., K.F., T.S., Y.K.)
| | - T Sato
- From the Departments of Radiology (Y.M., S.K., K.W., I.U., A.O., J.M., S.I., K.F., T.S., Y.K.)
| | - K Okada
- Neurology (K.O., T.U., S.T.), University of Occupational and Environmental Health, School of Medicine, Kitakyushu, Japan
| | - T Uozumi
- Neurology (K.O., T.U., S.T.), University of Occupational and Environmental Health, School of Medicine, Kitakyushu, Japan
| | - S Tsuji
- Neurology (K.O., T.U., S.T.), University of Occupational and Environmental Health, School of Medicine, Kitakyushu, Japan
| | - T Liu
- Departments of Biomedical Engineering and Radiology (T.L., Y.W.), Cornell University, New York, New York
| | - Y Wang
- Departments of Biomedical Engineering and Radiology (T.L., Y.W.), Cornell University, New York, New York
| | - Y Korogi
- From the Departments of Radiology (Y.M., S.K., K.W., I.U., A.O., J.M., S.I., K.F., T.S., Y.K.)
| |
Collapse
|
320
|
Xia S, Zheng G, Shen W, Liu S, Zhang LJ, Haacke EM, Lu GM. Quantitative measurements of brain iron deposition in cirrhotic patients using susceptibility mapping. Acta Radiol 2015; 56:339-46. [PMID: 24646625 DOI: 10.1177/0284185114525374] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND Susceptibility-weighted imaging (SWI) has been used to detect micro-bleeds and iron deposits in the brain. However, no reports have been published on the application of SWI in studying iron changes in the brain of cirrhotic patients. PURPOSE To compare the susceptibility of different brain structures in cirrhotic patients with that in healthy controls and to evaluate susceptibility as a potential biomarker and correlate the measured susceptibility and cadaveric brain iron concentration for a variety of brain structures. MATERIAL AND METHODS Forty-three cirrhotic patients (27 men, 16 women; mean age, 50 ± 9 years) and 34 age- and sex-matched healthy controls (22 men, 12 women; mean age, 47 ± 7 years) were included in this retrospective study. Susceptibility was measured in the frontal white matter, basal ganglia, midbrain, and dentate nucleus and compared with results gathered from two postmortem brain studies. Correlation between susceptibility and clinical biomarkers and neuropsychiatric tests scores was calculated. RESULTS In cirrhotic patients, the susceptibility of left frontal white matter, bilateral caudate head, and right substantia nigra was higher than that in healthy controls (P < 0.05). There was a positive correlation between susceptibility and iron concentration from one postmortem brain study (r = 0.835, P = 0.01) in eight deep grey matter structures and another in five brain structures (r = 0.900, P = 0.03). The susceptibility of right caudate head (r = 0.402) and left caudate head (r = 0.408) correlated with neuropsychological test scores (both P < 0.05). CONCLUSION Abnormal iron deposits occur in cirrhotic patients and abnormal susceptibility of some brain regions appears to reflect neurocognitive changes.
Collapse
Affiliation(s)
- Shuang Xia
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, PR China
- Department of Medical Imaging, Tianjin First Central Hospital, Tianjin, PR China
| | - Gang Zheng
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, PR China
| | - Wen Shen
- Department of Medical Imaging, Tianjin First Central Hospital, Tianjin, PR China
| | - Saifeng Liu
- McMaster University, Hamilton, Ontario, PR China
| | - Long Jiang Zhang
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, PR China
| | - E Mark Haacke
- Department of Radiology, Wayne State University, Detroit, MI, USA
| | - Guang Ming Lu
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, PR China
| |
Collapse
|
321
|
Langkammer C, Bredies K, Poser BA, Barth M, Reishofer G, Fan AP, Bilgic B, Fazekas F, Mainero C, Ropele S. Fast quantitative susceptibility mapping using 3D EPI and total generalized variation. Neuroimage 2015; 111:622-30. [PMID: 25731991 DOI: 10.1016/j.neuroimage.2015.02.041] [Citation(s) in RCA: 137] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 02/02/2015] [Accepted: 02/20/2015] [Indexed: 01/21/2023] Open
Abstract
Quantitative susceptibility mapping (QSM) allows new insights into tissue composition and organization by assessing its magnetic property. Previous QSM studies have already demonstrated that magnetic susceptibility is highly sensitive to myelin density and fiber orientation as well as to para- and diamagnetic trace elements. Image resolution in QSM with current approaches is limited by the long acquisition time of 3D scans and the need for high signal to noise ratio (SNR) to solve the dipole inversion problem. We here propose a new total-generalized-variation (TGV) based method for QSM reconstruction, which incorporates individual steps of phase unwrapping, background field removal and dipole inversion in a single iteration, thus yielding a robust solution to the reconstruction problem. This approach has beneficial characteristics for low SNR data, allowing for phase data to be rapidly acquired with a 3D echo planar imaging (EPI) sequence. The proposed method was evaluated with a numerical phantom and in vivo at 3 and 7 T. Compared to total variation (TV), TGV-QSM enforced higher order smoothness which yielded solutions closer to the ground truth and prevented stair-casing artifacts. The acquisition time for images with 1mm isotropic resolution and whole brain coverage was 10s on a clinical 3 Tesla scanner. In conclusion, 3D EPI acquisition combined with single-step TGV reconstruction yields reliable QSM images of the entire brain with 1mm isotropic resolution in seconds. The short acquisition time combined with the robust reconstruction may enable new QSM applications in less compliant populations, clinical susceptibility tensor imaging, and functional resting state examinations.
Collapse
Affiliation(s)
- Christian Langkammer
- MGH Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Harvard Medical School, Boston, MA, USA; Department of Neurology, Medical University of Graz, Graz, Austria.
| | - Kristian Bredies
- Institute of Mathematics and Scientific Computing, University of Graz, Graz, Austria
| | - Benedikt A Poser
- Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Markus Barth
- Centre for Advanced Imaging, The University of Queensland, Brisbane, Australia
| | - Gernot Reishofer
- Department of Radiology, Division of Neuroradiology, Medical University of Graz, Graz, Austria
| | - Audrey Peiwen Fan
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA; Lucas Center for Imaging, Stanford University, Stanford, CA, USA
| | - Berkin Bilgic
- MGH Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Harvard Medical School, Boston, MA, USA
| | - Franz Fazekas
- Department of Neurology, Medical University of Graz, Graz, Austria
| | - Caterina Mainero
- MGH Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Harvard Medical School, Boston, MA, USA
| | - Stefan Ropele
- Department of Neurology, Medical University of Graz, Graz, Austria
| |
Collapse
|
322
|
Barbosa JHO, Santos AC, Tumas V, Liu M, Zheng W, Haacke EM, Salmon CEG. Quantifying brain iron deposition in patients with Parkinson's disease using quantitative susceptibility mapping, R2 and R2. Magn Reson Imaging 2015; 33:559-65. [PMID: 25721997 DOI: 10.1016/j.mri.2015.02.021] [Citation(s) in RCA: 187] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 08/19/2014] [Accepted: 02/16/2015] [Indexed: 10/24/2022]
Abstract
PURPOSE To evaluate the sensitivity and specificity of quantitative magnetic resonance (MR) iron mapping including R2, R2* and magnetic susceptibility to differentiate patients with Parkinson's disease (PD) from healthy controls. MATERIALS AND METHODS Thirty (30) healthy controls (HC) (64±7years old) and 20 patients with idiopathic PD (66±8years old) were studied using a 3T MR imaging scanner. R2 maps were generated from GRASE sequence while R2*, and quantitative susceptibility mapping (QSM) were obtained from a conventional multi-echo gradient-echo sequence. R2, R2* and relative susceptibility (Δχ) values of structures in the basal ganglia were measured for each patient and control. An analysis of sensitivity and specificity and unpaired t-test was applied to the two groups. RESULTS A significant difference (p<0.05) was found for R2 and ∆χ values in the substantia nigra as a whole and in the pars compacta for PD patients. The R2* values were different significantly (p<0.05) only on the substantia nigra pars compacta. QSM presented the highest sensitivity and specificity to differentiate the two populations. CONCLUSION The QSM map was the most sensitive quantitative technique for detecting a significant increase of iron for PD. The highest significant difference between controls and patients was found in the substantia nigra pars compacta using QSM.
Collapse
Affiliation(s)
- Jeam Haroldo Oliveira Barbosa
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
| | - Antonio Carlos Santos
- Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Vitor Tumas
- Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Manju Liu
- MRI Institute for Biomedical Research, Detroit, MI, United States
| | - Weili Zheng
- MRI Institute for Biomedical Research, Detroit, MI, United States
| | - E Mark Haacke
- MRI Institute for Biomedical Research, Detroit, MI, United States; Wayne State University, Detroit, MI, United States
| | - Carlos Ernesto Garrido Salmon
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| |
Collapse
|
323
|
Deng W, Boada F, Poser BA, Schirda C, Stenger VA. Iterative projection onto convex sets for quantitative susceptibility mapping. Magn Reson Med 2015; 73:697-703. [PMID: 24604410 PMCID: PMC4156936 DOI: 10.1002/mrm.25155] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Revised: 01/09/2014] [Accepted: 01/10/2014] [Indexed: 11/06/2022]
Abstract
PURPOSE Quantitative susceptibility map (QSM) reconstruction is ill posed due to the zero values on the "magic angle cone" that make the maps prone to streaking artifacts. We propose projection onto convex sets (POCS) in the method of steepest descent (SD) for QSM reconstruction. METHODS Two convex projections, an object-support projection in the image domain and a projection in k-space were used. QSM reconstruction using the proposed SD-POCS method was compared with SD and POCS alone as well as with truncated k-space division (TKD) for numerically simulated and 7 Tesla (T) human brain phase data. RESULTS The QSM reconstruction error from noise-free simulated phase data using SD-POCS is at least two orders of magnitude lower than using SD, POCS, or TKD and has reduced streaking artifacts. Using the l1 -TV reconstructed susceptibility as a gold standard for 7T in vivo imaging, SD-POCS showed better image quality comparing to SD, POCS, or TKD from visual inspection. CONCLUSION POCS is an alternative method for regularization that can be used in an iterative minimization method such as SD for QSM reconstruction.
Collapse
Affiliation(s)
- Weiran Deng
- University of Hawaii, John A. Burns School of Medicine, Honolulu, HI
| | | | - Benedikt A. Poser
- University of Hawaii, John A. Burns School of Medicine, Honolulu, HI
| | - Claudiu Schirda
- University of Pittsburgh, Department of Radiology, Pittsburgh, PA
| | - V. A. Stenger
- University of Hawaii, John A. Burns School of Medicine, Honolulu, HI
| |
Collapse
|
324
|
A modulated closed form solution for quantitative susceptibility mapping — A thorough evaluation and comparison to iterative methods based on edge prior knowledge. Neuroimage 2015; 107:163-174. [DOI: 10.1016/j.neuroimage.2014.11.038] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 11/13/2014] [Accepted: 11/18/2014] [Indexed: 11/18/2022] Open
|
325
|
Hsieh CY, Cheng YCN, Neelavalli J, Haacke EM, Stafford RJ. An improved method for susceptibility and radius quantification of cylindrical objects from MRI. Magn Reson Imaging 2015; 33:420-36. [PMID: 25633922 DOI: 10.1016/j.mri.2015.01.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Revised: 12/12/2014] [Accepted: 01/09/2015] [Indexed: 02/06/2023]
Abstract
A new method is developed to measure the magnetic susceptibilities and radii of small cylinder-like objects at arbitrary orientations accurately. This method for most biological substances only requires a standard gradient echo sequence with one or two echo times, depending on the orientation of an object relative to the main magnetic field. For objects oriented at the magic angle, however, this method is not applicable. As a byproduct of this method, the cross-sectional area as well as signals inside and outside the object can be determined. The uncertainty of each measurement is estimated from the error propagation method. Partial volume, dephasing, and phase aliasing effects are naturally included in the equations of this method. A number of simulations, phantom, and pilot in-vivo human studies are carried out to validate the theory. When the maximal phase value at the boundary of a given cylindrical object is larger than 3 radians, and the phase inside the object is more than 1 radian, the susceptibility can be accurately quantified within 15%. The radius of the object can be determined to subpixel accuracy. This is the case when the signal-to-noise ratio inside the object is about 6:1 or higher and the radius of the object is about one pixel or larger. These conditions are realistic when considering medullary and pial veins for example.
Collapse
Affiliation(s)
- Ching-Yi Hsieh
- Medical Physics Program, Wayne State University, Detroit, MI 48201
| | - Yu-Chung N Cheng
- Department of Radiology, Wayne State University, Detroit, MI 48201.
| | | | - E Mark Haacke
- Department of Radiology, Wayne State University, Detroit, MI 48201
| | - R Jason Stafford
- Department of Imaging Physics, The University of Texas, MD Anderson Cancer Center, Houston, TX 77030
| |
Collapse
|
326
|
Evaluation of iron content in human cerebral cavernous malformation using quantitative susceptibility mapping. Invest Radiol 2015; 49:498-504. [PMID: 24619210 DOI: 10.1097/rli.0000000000000043] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
OBJECTIVES The aims of this study were to investigate and validate quantitative susceptibility mapping (QSM) for lesional iron quantification in cerebral cavernous malformations (CCMs). MATERIALS AND METHODS Magnetic resonance imaging studies were performed in phantoms and 16 patients on a 3-T scanner. Susceptibility weighted imaging, QSM, and R2* maps were reconstructed from in vivo data acquired with a 3-dimensional, multi-echo, and T2*-weighted gradient echo sequence. Magnetic susceptibility measurements were correlated to susceptibility weighted imaging and R2* results. In addition, iron concentrations from surgically excised CCM lesion specimens were determined using inductively coupled plasma mass spectrometry and correlated with QSM measurements. RESULTS The QSM images demonstrated excellent image quality for depicting CCM lesions in both sporadic and familial cases. Susceptibility measurements revealed a positive linear correlation with R2* values (R(2) = 0.99 for total, R(2) = 0.69 for mean; P < 0.01). Quantitative susceptibility mapping values of known iron-rich brain regions matched closely with those of previous studies and in interobserver consistency. A strong correlation was found between QSM and the concentration of iron phantoms (0.925; P < 0.01), as well as between QSM and mass spectroscopy estimation of iron deposition (0.999 for total iron, 0.86 for iron concentration; P < 0.01) in 18 fragments of 4 excised human CCM lesion specimens. CONCLUSIONS The ability of QSM to evaluate iron deposition in CCM lesions was illustrated via phantom, in vivo, and ex vivo validation studies. Quantitative susceptibility mapping may be a potential biomarker for monitoring CCM disease activity and response to treatments.
Collapse
|
327
|
Sun H, Walsh AJ, Lebel RM, Blevins G, Catz I, Lu JQ, Johnson ES, Emery DJ, Warren KG, Wilman AH. Validation of quantitative susceptibility mapping with Perls' iron staining for subcortical gray matter. Neuroimage 2015; 105:486-92. [DOI: 10.1016/j.neuroimage.2014.11.010] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 09/26/2014] [Accepted: 11/04/2014] [Indexed: 01/25/2023] Open
|
328
|
Poynton C, Jenkinson M, Adalsteinsson E, Sullivan EV, Pfefferbaum A, Wells W. Quantitative susceptibility mapping by inversion of a perturbation field model: correlation with brain iron in normal aging. IEEE TRANSACTIONS ON MEDICAL IMAGING 2015; 34:339-353. [PMID: 25248179 PMCID: PMC4404631 DOI: 10.1109/tmi.2014.2358552] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
There is increasing evidence that iron deposition occurs in specific regions of the brain in normal aging and neurodegenerative disorders such as Parkinson's, Huntington's, and Alzheimer's disease. Iron deposition changes the magnetic susceptibility of tissue, which alters the MR signal phase, and allows estimation of susceptibility differences using quantitative susceptibility mapping (QSM). We present a method for quantifying susceptibility by inversion of a perturbation model, or "QSIP." The perturbation model relates phase to susceptibility using a kernel calculated in the spatial domain, in contrast to previous Fourier-based techniques. A tissue/air susceptibility atlas is used to estimate B0 inhomogeneity. QSIP estimates in young and elderly subjects are compared to postmortem iron estimates, maps of the Field-Dependent Relaxation Rate Increase, and the L1-QSM method. Results for both groups showed excellent agreement with published postmortem data and in vivo FDRI: statistically significant Spearman correlations ranging from Rho=0.905 to Rho=1.00 were obtained. QSIP also showed improvement over FDRI and L1-QSM: reduced variance in susceptibility estimates and statistically significant group differences were detected in striatal and brainstem nuclei, consistent with age-dependent iron accumulation in these regions.
Collapse
Affiliation(s)
| | - Mark Jenkinson
- Oxford Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB), Nuffield Department of Clinical Neuro-sciences, John Radcliffe Hospital, University of Oxford, OX3 9DU UK
| | - Elfar Adalsteinsson
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, 02139 USA and also with the Harvard-MIT Division of Health Sciences and Technology (HST) Massachusetts Institute of Technology, Cambridge, MA, 02139
| | - Edith V. Sullivan
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA, 94305 USA
| | - Adolf Pfefferbaum
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA, 94305 USA and with the Neuroscience Program, SRI International, Menlo Park, CA, 94025 USA
| | - William Wells
- Surgical Planning Laboratory, Department of Radiology, Harvard Medical School and Brigham and Womens Hospital, Boston, MA, 02115 USA, and also with the Computer Science and Artificial Intelligence Lab, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| |
Collapse
|
329
|
Wang Y, Liu T. Quantitative susceptibility mapping (QSM): Decoding MRI data for a tissue magnetic biomarker. Magn Reson Med 2015; 73:82-101. [PMID: 25044035 PMCID: PMC4297605 DOI: 10.1002/mrm.25358] [Citation(s) in RCA: 577] [Impact Index Per Article: 64.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 06/13/2014] [Accepted: 06/18/2014] [Indexed: 01/03/2023]
Abstract
In MRI, the main magnetic field polarizes the electron cloud of a molecule, generating a chemical shift for observer protons within the molecule and a magnetic susceptibility inhomogeneity field for observer protons outside the molecule. The number of water protons surrounding a molecule for detecting its magnetic susceptibility is vastly greater than the number of protons within the molecule for detecting its chemical shift. However, the study of tissue magnetic susceptibility has been hindered by poor molecular specificities of hitherto used methods based on MRI signal phase and T2* contrast, which depend convolutedly on surrounding susceptibility sources. Deconvolution of the MRI signal phase can determine tissue susceptibility but is challenged by the lack of MRI signal in the background and by the zeroes in the dipole kernel. Recently, physically meaningful regularizations, including the Bayesian approach, have been developed to enable accurate quantitative susceptibility mapping (QSM) for studying iron distribution, metabolic oxygen consumption, blood degradation, calcification, demyelination, and other pathophysiological susceptibility changes, as well as contrast agent biodistribution in MRI. This paper attempts to summarize the basic physical concepts and essential algorithmic steps in QSM, to describe clinical and technical issues under active development, and to provide references, codes, and testing data for readers interested in QSM.
Collapse
Affiliation(s)
- Yi Wang
- Radiology, Weill Medical College of Cornell UniversityNew York, New York, USA
- Biomedical Engineering, Cornell UniversityIthaca, New York, USA
- Biomedical Engineering, Kyung Hee UniversitySeoul, South Korea
| | - Tian Liu
- MedImageMetric, LLCNew York, New York, USA
| |
Collapse
|
330
|
Dibb R, Li W, Cofer G, Liu C. Microstructural origins of gadolinium-enhanced susceptibility contrast and anisotropy. Magn Reson Med 2014; 72:1702-11. [PMID: 24443202 PMCID: PMC4102673 DOI: 10.1002/mrm.25082] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 11/21/2013] [Accepted: 11/25/2013] [Indexed: 01/20/2023]
Abstract
PURPOSE MR histology based on magnetic susceptibility can be used to visualize diamagnetic myelin (and its deterioration) in the central nervous system and is facilitated by the application of high magnetic field strengths and paramagnetic contrast agents. Characterizing the effect of these tools will aid in assessing white matter myelin content and microstructure. METHODS Image data from six gadolinium-perfused mouse brain specimens were acquired at 2.0, 7.0, and 9.4 Tesla. Magnetic susceptibility contrast was analyzed for its dependence on field strength, gadolinium concentration, and white matter fiber orientation. A model for this contrast is presented based on the three-pool model for white matter. RESULTS The specimen data illustrate that white-gray matter susceptibility contrast is field strength independent. White-gray matter contrast improves significantly as a function of gadolinium contrast agent in the tissue, i.e., white matter appears increasingly more diamagnetic relative to gray matter. The simulated data from the model suggest that susceptibility anisotropy of white matter fiber bundles increases nonlinearly as a function of gadolinium concentration due to contrast agent compartmentalization into the extracellular white matter water pool. CONCLUSION Using contrast agents in MR histology facilitates white-gray matter susceptibility contrast modulation and the probing of white matter microstructure and orientation.
Collapse
Affiliation(s)
- Russell Dibb
- Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, USA
- Biomedical Engineering, Duke University, Durham, NC, USA
| | - Wei Li
- Brain Imaging & Analysis Center, Duke University Medical Center, Durham, NC, USA
| | - Gary Cofer
- Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, USA
| | - Chunlei Liu
- Brain Imaging & Analysis Center, Duke University Medical Center, Durham, NC, USA
- Radiology, Duke University Medical Center, Durham, NC, USA
| |
Collapse
|
331
|
Ward RJ, Zucca FA, Duyn JH, Crichton RR, Zecca L. The role of iron in brain ageing and neurodegenerative disorders. Lancet Neurol 2014; 13:1045-60. [PMID: 25231526 DOI: 10.1016/s1474-4422(14)70117-6] [Citation(s) in RCA: 1127] [Impact Index Per Article: 112.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
SUMMARY In the CNS, iron in several proteins is involved in many important processes such as oxygen transportation, oxidative phosphorylation, myelin production, and the synthesis and metabolism of neurotransmitters. Abnormal iron homoeostasis can induce cellular damage through hydroxyl radical production, which can cause the oxidation and modification of lipids, proteins, carbohydrates, and DNA. During ageing, different iron complexes accumulate in brain regions associated with motor and cognitive impairment. In various neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease, changes in iron homoeostasis result in altered cellular iron distribution and accumulation. MRI can often identify these changes, thus providing a potential diagnostic biomarker of neurodegenerative diseases. An important avenue to reduce iron accumulation is the use of iron chelators that are able to cross the blood-brain barrier, penetrate cells, and reduce excessive iron accumulation, thereby affording neuroprotection.
Collapse
Affiliation(s)
- Roberta J Ward
- Centre for Neuroinflammation and Neurodegeneration, Department of Medicine, Hammersmith Hospital Campus, Imperial College London, London, UK; Faculte de Science, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Fabio A Zucca
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate, Milan, Italy
| | - Jeff H Duyn
- Advanced MRI Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Robert R Crichton
- Faculte de Science, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Luigi Zecca
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate, Milan, Italy.
| |
Collapse
|
332
|
Zhang Z, Liao W, Bernhardt B, Wang Z, Sun K, Yang F, Liu Y, Lu G. Brain iron redistribution in mesial temporal lobe epilepsy: a susceptibility-weighted magnetic resonance imaging study. BMC Neurosci 2014; 15:117. [PMID: 25413842 PMCID: PMC4243317 DOI: 10.1186/s12868-014-0117-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 10/07/2014] [Indexed: 11/15/2022] Open
Abstract
Background The roles of iron in epilepsy and its pathophysiological significance are poorly understood, especially whether iron levels are abnormal in subcortcal structures. This study aims to demonstrate whole-brain iron alterations and its clinical relevancies in mesial temporal lobe epilepsy (mTLE) in vivo, using susceptibility-weighted magnetic resonance imaging (SWI). Methods We studied 62 patients with mTLE and 62 healthy controls. Brain iron concentration was quantified using SWI phase values. Voxel-wise analysis was carried out to compare iron levels between mTLE and controls, and to assess the relationship between altered iron concentration and clinical parameters in mTLE. Results Patients with mTLE showed decreases of iron levels in the subcortical structures such as substantia nigra, red nucleus, and basal ganglia. Conversely, iron levels were decreased in the cortex. Subcortical iron levels were negatively correlated to those in the cortex. Moreover, cortical and basal ganglia iron levels were related to clinical variables including epilepsy duration, age at seizures onset, and histories of precipitating factors. Conclusions Our SWI findings suggest a redistribution of iron between subcortical and cortical structures in mTLE. The degree of redistribution is affected by both progression of epilepsy and precipitating factors. Investigation on brain iron redistribution offers new insights into the pathogenesis of mTLE, and may be a potential biomarker for monitoring the clinical progression of epilepsy. Electronic supplementary material The online version of this article (doi:10.1186/s12868-014-0117-3) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Zhiqiang Zhang
- Department of Medical Imaging, Jinling Hospital, Nanjing University School of Medicine, 305# Eastern Zhongshan Rd, Nanjing, 210002, China.
| | - Wei Liao
- Department of Medical Imaging, Jinling Hospital, Nanjing University School of Medicine, 305# Eastern Zhongshan Rd, Nanjing, 210002, China. .,Center for Cognition and Brain Disorders, Affiliated Hospital of Hangzhou Normal University, Hangzhou, 310015, China.
| | - Boris Bernhardt
- Department of Social Neuroscience, Max Planck Institute for Human Cognitive and Brain Science, Leipzig, Germany.
| | - Zhengge Wang
- Department of Medical Imaging, Jinling Hospital, Nanjing University School of Medicine, 305# Eastern Zhongshan Rd, Nanjing, 210002, China.
| | - Kangjian Sun
- Department of Neurosurgery, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, China.
| | - Fang Yang
- Department of Neurology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, China.
| | - Yijun Liu
- Department of Psychiatry and Neuroscience, University of Florida, Gainesville, Fl, USA.
| | - Guangming Lu
- Department of Medical Imaging, Jinling Hospital, Nanjing University School of Medicine, 305# Eastern Zhongshan Rd, Nanjing, 210002, China.
| |
Collapse
|
333
|
Phase-corrected bipolar gradients in multi-echo gradient-echo sequences for quantitative susceptibility mapping. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2014; 28:347-55. [PMID: 25408108 DOI: 10.1007/s10334-014-0470-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 09/25/2014] [Accepted: 10/22/2014] [Indexed: 10/24/2022]
Abstract
OBJECTIVE Large echo spacing of unipolar readout gradients in current multi-echo gradient-echo (GRE) sequences for mapping fields in quantitative susceptibility mapping (QSM) can be reduced using bipolar readout gradients thereby improving acquisition efficiency. MATERIALS AND METHODS Phase discrepancies between odd and even echoes in the bipolar readout gradients caused by non-ideal gradient behaviors were measured, modeled as polynomials in space and corrected for accordingly in field mapping. The bipolar approach for multi-echo GRE field mapping was compared with the unipolar approach for QSM. RESULTS The odd-even-echo phase discrepancies were approximately constant along the phase encoding direction and linear along the readout and slice-selection directions. A simple linear phase correction in all three spatial directions was shown to enable accurate QSM of the human brain using a bipolar multi-echo GRE sequence. Bipolar multi-echo acquisition provides QSM in good quantitative agreement with unipolar acquisition while also reducing noise. CONCLUSION With a linear phase correction between odd-even echoes, bipolar readout gradients can be used in multi-echo GRE sequences for QSM.
Collapse
|
334
|
Janaway BM, Simpson JE, Hoggard N, Highley JR, Forster G, Drew D, Gebril OH, Matthews FE, Brayne C, Wharton SB, Ince PG. Brain haemosiderin in older people: pathological evidence for an ischaemic origin of magnetic resonance imaging (MRI) microbleeds. Neuropathol Appl Neurobiol 2014; 40:258-69. [PMID: 23678850 PMCID: PMC4282337 DOI: 10.1111/nan.12062] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Accepted: 05/10/2013] [Indexed: 01/03/2023]
Abstract
Introduction Magnetic resonance imaging (MRI) cerebral microbleeds (CMB) arise from ferromagnetic haemosiderin iron assumed to derive from extravasation of erythrocytes. Light microscopy of ageing brain frequently reveals foci of haemosiderin from single crystalloids to larger, predominantly perivascular, aggregates. The pathological and radiological relationship between these findings is not resolved. Methods Haemosiderin deposition and vascular pathology in the putamen were quantified in 200 brains donated to the population-representative Medical Research Council Cognitive Function and Ageing Study. Molecular markers of gliosis and tissue integrity were assessed by immunohistochemistry in brains with highest (n = 20) and lowest (n = 20) levels of putamen haemosiderin. The association between haemosiderin counts and degenerative and vascular brain pathology, clinical data, and the haemochromatosis (HFE) gene H63D genotype were analysed. The frequency of MRI CMB in 10 cases with highest and lowest burden of putamen haemosiderin, was compared using post mortem 3T MRI. Results Greater putamen haemosiderin was significantly associated with putaminal indices of small vessel ischaemia (microinfarcts, P < 0.05; arteriolosclerosis, P < 0.05; perivascular attenuation, P < 0.001) and with lacunes in any brain region (P < 0.023) but not large vessel disease, or whole brain measures of neurodegenerative pathology. Higher levels of putamen haemosiderin correlated with more CMB (P < 0.003). Conclusions The MRI-CMB concept should take account of brain iron homeostasis, and small vessel ischaemic change in later life, rather than only as a marker for minor episodes of cerebrovascular extravasation. These data are of clinical relevance, suggesting that basal ganglia MRI microbleeds may be a surrogate for ischaemic small vessel disease rather than exclusively a haemorrhagic diathesis.
Collapse
Affiliation(s)
- B M Janaway
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
335
|
Bilgic B, Fan AP, Polimeni JR, Cauley SF, Bianciardi M, Adalsteinsson E, Wald LL, Setsompop K. Fast quantitative susceptibility mapping with L1-regularization and automatic parameter selection. Magn Reson Med 2014; 72:1444-59. [PMID: 24259479 PMCID: PMC4111791 DOI: 10.1002/mrm.25029] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Revised: 10/11/2013] [Accepted: 10/14/2013] [Indexed: 11/06/2022]
Abstract
PURPOSE To enable fast reconstruction of quantitative susceptibility maps with total variation penalty and automatic regularization parameter selection. METHODS ℓ(1) -Regularized susceptibility mapping is accelerated by variable splitting, which allows closed-form evaluation of each iteration of the algorithm by soft thresholding and fast Fourier transforms. This fast algorithm also renders automatic regularization parameter estimation practical. A weighting mask derived from the magnitude signal can be incorporated to allow edge-aware regularization. RESULTS Compared with the nonlinear conjugate gradient (CG) solver, the proposed method is 20 times faster. A complete pipeline including Laplacian phase unwrapping, background phase removal with SHARP filtering, and ℓ(1) -regularized dipole inversion at 0.6 mm isotropic resolution is completed in 1.2 min using MATLAB on a standard workstation compared with 22 min using the CG solver. This fast reconstruction allows estimation of regularization parameters with the L-curve method in 13 min, which would have taken 4 h with the CG algorithm. The proposed method also permits magnitude-weighted regularization, which prevents smoothing across edges identified on the magnitude signal. This more complicated optimization problem is solved 5 times faster than the nonlinear CG approach. Utility of the proposed method is also demonstrated in functional blood oxygen level-dependent susceptibility mapping, where processing of the massive time series dataset would otherwise be prohibitive with the CG solver. CONCLUSION Online reconstruction of regularized susceptibility maps may become feasible with the proposed dipole inversion.
Collapse
Affiliation(s)
- Berkin Bilgic
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Audrey P. Fan
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, MA, USA
| | - Jonathan R. Polimeni
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Department of Radiology, Harvard Medical School, Boston, Massachusetts, USA
| | - Stephen F. Cauley
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Marta Bianciardi
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Department of Radiology, Harvard Medical School, Boston, Massachusetts, USA
| | - Elfar Adalsteinsson
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, MA, USA
- Harvard-MIT Health Sciences and Technology, Cambridge, MA, USA
| | - Lawrence L. Wald
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Department of Radiology, Harvard Medical School, Boston, Massachusetts, USA
- Harvard-MIT Health Sciences and Technology, Cambridge, MA, USA
| | - Kawin Setsompop
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Department of Radiology, Harvard Medical School, Boston, Massachusetts, USA
| |
Collapse
|
336
|
Internal structures of the globus pallidus in patients with Parkinson’s disease: evaluation with quantitative susceptibility mapping (QSM). Eur Radiol 2014; 25:710-8. [DOI: 10.1007/s00330-014-3472-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Revised: 09/08/2014] [Accepted: 10/15/2014] [Indexed: 10/24/2022]
|
337
|
Ramos P, Santos A, Pinto NR, Mendes R, Magalhães T, Almeida A. Anatomical region differences and age-related changes in copper, zinc, and manganese levels in the human brain. Biol Trace Elem Res 2014; 161:190-201. [PMID: 25119708 DOI: 10.1007/s12011-014-0093-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 07/25/2014] [Indexed: 12/14/2022]
Abstract
Using inductively coupled plasma-mass spectrometry after samples microwave-assisted acid digestion, zinc (Zn), copper (Cu), and manganese (Mn) levels were measured in 14 different areas of the human brain of adult individuals (n = 42; 71 ± 12, range 50-101 years old) without a known history of neurodegenerative, neurological, or psychiatric disorder. The main goals of the work were to establish the "normal" (reference) values for those elements in the human brain and to evaluate the age-related changes, a prior and indispensable step in order to enlighten the role of trace element (TE) in human brain physiology and their involvement in aging and neurodegenerative processes. Considering the mean values for the 14 regions, Zn (mean ± sd; range 53 ± 5; 43-61 μg/g) was found at higher levels, followed by Cu (22 ± 5; 10-37 μg/g) and Mn (1.3 ± 0.3; 0.5-2.7 μg/g). The TE distribution across the brain tissue showed to be quite heterogeneous: the highest levels of Zn were found in the hippocampus (70 ± 10; 49-95 μg/g) and superior temporal gyrus (68 ± 10; 44-88 μg/g) and the lowest in the pons (33 ± 8; 19-51 μg/g); the highest levels of Cu and Mn were found in the putamen (36 ± 13; 21-76 μg/g and 2.5 ± 0.8; 0.7-4.5 μg/g, respectively) and the lowest in the medulla (11 ± 6; 2-30 μg/g and 0.8 ± 0.3; 0.2-1.8 μg/g, respectively). A tendency for an age-related increase in Zn and Mn levels was observed in most brain regions while Cu levels showed to be negatively correlated with age.
Collapse
Affiliation(s)
- Patrícia Ramos
- REQUIMTE, Department of Chemical Sciences, Laboratory of Applied Chemistry, Faculty of Pharmacy, Porto University, Rua de Jorge Viterbo Ferreira 228, 4050-313, Porto, Portugal
| | | | | | | | | | | |
Collapse
|
338
|
Haacke EM, Liu S, Buch S, Zheng W, Wu D, Ye Y. Quantitative susceptibility mapping: current status and future directions. Magn Reson Imaging 2014; 33:1-25. [PMID: 25267705 DOI: 10.1016/j.mri.2014.09.004] [Citation(s) in RCA: 353] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 09/14/2014] [Accepted: 09/22/2014] [Indexed: 01/13/2023]
Abstract
Quantitative susceptibility mapping (QSM) is a new technique for quantifying magnetic susceptibility. It has already found various applications in quantifying in vivo iron content, calcifications and changes in venous oxygen saturation. The accuracy of susceptibility mapping is dependent on several factors. In this review, we evaluate the entire process of QSM from data acquisition to individual data processing steps. We also show preliminary results of several new concepts introduced in this review in an attempt to improve the quality and accuracy for certain steps. The uncertainties in estimating susceptibility differences using susceptibility maps, phase images, and T2* maps are analyzed and compared. Finally, example clinical applications are presented. We conclude that QSM holds great promise in quantifying iron and becoming a standard clinical tool.
Collapse
Affiliation(s)
- E Mark Haacke
- Department of Radiology, Wayne State University, Detroit, MI, USA; School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada; Shanghai Key Laboratory of Magnetic Resonance, East China Normal University, Shanghai, China.
| | - Saifeng Liu
- School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada
| | - Sagar Buch
- School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada
| | - Weili Zheng
- Department of Radiology, Wayne State University, Detroit, MI, USA
| | - Dongmei Wu
- Shanghai Key Laboratory of Magnetic Resonance, East China Normal University, Shanghai, China
| | - Yongquan Ye
- Department of Radiology, Wayne State University, Detroit, MI, USA
| |
Collapse
|
339
|
Lin PY, Chao TC, Wu ML. Quantitative susceptibility mapping of human brain at 3T: a multisite reproducibility study. AJNR Am J Neuroradiol 2014; 36:467-74. [PMID: 25339652 DOI: 10.3174/ajnr.a4137] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Quantitative susceptibility mapping of the human brain has demonstrated strong potential in examining iron deposition, which may help in investigating possible brain pathology. This study assesses the reproducibility of quantitative susceptibility mapping across different imaging sites. MATERIALS AND METHODS In this study, the susceptibility values of 5 regions of interest in the human brain were measured on 9 healthy subjects following calibration by using phantom experiments. Each of the subjects was imaged 5 times on 1 scanner with the same procedure repeated on 3 different 3T systems so that both within-site and cross-site quantitative susceptibility mapping precision levels could be assessed. Two quantitative susceptibility mapping algorithms, similar in principle, one by using iterative regularization (iterative quantitative susceptibility mapping) and the other with analytic optimal solutions (deterministic quantitative susceptibility mapping), were implemented, and their performances were compared. RESULTS Results show that while deterministic quantitative susceptibility mapping had nearly 700 times faster computation speed, residual streaking artifacts seem to be more prominent compared with iterative quantitative susceptibility mapping. With quantitative susceptibility mapping, the putamen, globus pallidus, and caudate nucleus showed smaller imprecision on the order of 0.005 ppm, whereas the red nucleus and substantia nigra, closer to the skull base, had a somewhat larger imprecision of approximately 0.01 ppm. Cross-site errors were not significantly larger than within-site errors. Possible sources of estimation errors are discussed. CONCLUSIONS The reproducibility of quantitative susceptibility mapping in the human brain in vivo is regionally dependent, and the precision levels achieved with quantitative susceptibility mapping should allow longitudinal and multisite studies such as aging-related changes in brain tissue magnetic susceptibility.
Collapse
Affiliation(s)
- P-Y Lin
- From the Department of Computer Science and Information Engineering (P.-Y.L., T.-C.C., M.-L.W.)
| | - T-C Chao
- From the Department of Computer Science and Information Engineering (P.-Y.L., T.-C.C., M.-L.W.) Institute of Medical Informatics (T.-C.C., M.-L.W.), National Cheng Kung University, Tainan, Taiwan
| | - M-L Wu
- From the Department of Computer Science and Information Engineering (P.-Y.L., T.-C.C., M.-L.W.) Institute of Medical Informatics (T.-C.C., M.-L.W.), National Cheng Kung University, Tainan, Taiwan.
| |
Collapse
|
340
|
Li W, Langkammer C, Chou YH, Petrovic K, Schmidt R, Song AW, Madden DJ, Ropele S, Liu C. Association between increased magnetic susceptibility of deep gray matter nuclei and decreased motor function in healthy adults. Neuroimage 2014; 105:45-52. [PMID: 25315786 DOI: 10.1016/j.neuroimage.2014.10.009] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 08/19/2014] [Accepted: 10/05/2014] [Indexed: 12/18/2022] Open
Abstract
In the human brain, iron is more prevalent in gray matter than in white matter, and deep gray matter structures, particularly the globus pallidus, putamen, caudate nucleus, substantia nigra, red nucleus, and dentate nucleus, exhibit especially high iron content. Abnormally elevated iron levels have been found in various neurodegenerative diseases. Additionally, iron overload and related neurodegeneration may also occur during aging, but the functional consequences are not clear. In this study, we explored the correlation between magnetic susceptibility--a surrogate marker of brain iron--of these gray matter structures with behavioral measures of motor and cognitive abilities, in 132 healthy adults aged 40-83 years. Latent variables corresponding to manual dexterity and executive functions were obtained using factor analysis. The factor scores for manual dexterity declined significantly with increasing age. Independent of gender, age, and global cognitive function, increasing magnetic susceptibility in the globus pallidus and red nuclei was associated with decreasing manual dexterity. This finding suggests the potential value of magnetic susceptibility, a non-invasive quantitative imaging marker of iron, for the study of iron-related brain function changes.
Collapse
Affiliation(s)
- Wei Li
- Brain Imaging and Analysis Center, Duke University Medical Center, Durham, NC 27710, USA; Research Imaging Institute, University of Texas Health Science Center at San Antonio, TX 78229, USA; Department of Ophthalmology, University of Texas Health Science Center at San Antonio, TX 78229, USA
| | | | - Ying-Hui Chou
- Brain Imaging and Analysis Center, Duke University Medical Center, Durham, NC 27710, USA
| | - Katja Petrovic
- Department of Neurology, Medical University of Graz, Graz, Austria
| | - Reinhold Schmidt
- Department of Neurology, Medical University of Graz, Graz, Austria
| | - Allen W Song
- Brain Imaging and Analysis Center, Duke University Medical Center, Durham, NC 27710, USA; Department of Radiology, Duke University Medical Center, Durham, NC 27710, USA
| | - David J Madden
- Brain Imaging and Analysis Center, Duke University Medical Center, Durham, NC 27710, USA; Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC 27710, USA
| | - Stefan Ropele
- Department of Neurology, Medical University of Graz, Graz, Austria.
| | - Chunlei Liu
- Brain Imaging and Analysis Center, Duke University Medical Center, Durham, NC 27710, USA; Department of Radiology, Duke University Medical Center, Durham, NC 27710, USA.
| |
Collapse
|
341
|
Liu C, Li W, Tong KA, Yeom KW, Kuzminski S. Susceptibility-weighted imaging and quantitative susceptibility mapping in the brain. J Magn Reson Imaging 2014; 42:23-41. [PMID: 25270052 DOI: 10.1002/jmri.24768] [Citation(s) in RCA: 358] [Impact Index Per Article: 35.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 09/04/2014] [Accepted: 09/05/2014] [Indexed: 12/12/2022] Open
Abstract
Susceptibility-weighted imaging (SWI) is a magnetic resonance imaging (MRI) technique that enhances image contrast by using the susceptibility differences between tissues. It is created by combining both magnitude and phase in the gradient echo data. SWI is sensitive to both paramagnetic and diamagnetic substances which generate different phase shift in MRI data. SWI images can be displayed as a minimum intensity projection that provides high resolution delineation of the cerebral venous architecture, a feature that is not available in other MRI techniques. As such, SWI has been widely applied to diagnose various venous abnormalities. SWI is especially sensitive to deoxygenated blood and intracranial mineral deposition and, for that reason, has been applied to image various pathologies including intracranial hemorrhage, traumatic brain injury, stroke, neoplasm, and multiple sclerosis. SWI, however, does not provide quantitative measures of magnetic susceptibility. This limitation is currently being addressed with the development of quantitative susceptibility mapping (QSM) and susceptibility tensor imaging (STI). While QSM treats susceptibility as isotropic, STI treats susceptibility as generally anisotropic characterized by a tensor quantity. This article reviews the basic principles of SWI, its clinical and research applications, the mechanisms governing brain susceptibility properties, and its practical implementation, with a focus on brain imaging.
Collapse
Affiliation(s)
- Chunlei Liu
- Brain Imaging and Analysis Center, School of Medicine, Duke University, Durham, North Carolina, USA.,Department of Radiology, School of Medicine, Duke University, Durham, North Carolina, USA
| | - Wei Li
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, Texas, USA.,Department of Ophthalmology, University of Texas Health Science Center at San Antonio, Texas, USA
| | - Karen A Tong
- Department of Radiology, School of Medicine, Loma Linda University, Loma Linda, California, USA
| | - Kristen W Yeom
- Department of Radiology, Lucile Packard Children's Hospital, Stanford University, Palo Alto, California, USA
| | - Samuel Kuzminski
- Department of Radiology, School of Medicine, Duke University, Durham, North Carolina, USA
| |
Collapse
|
342
|
Ward RJ, Zucca FA, Duyn JH, Crichton RR, Zecca L. The role of iron in brain ageing and neurodegenerative disorders. Lancet Neurol 2014. [PMID: 25231526 DOI: 10.1016/s1474-4422(14)70117-6.(] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
In the CNS, iron in several proteins is involved in many important processes such as oxygen transportation, oxidative phosphorylation, myelin production, and the synthesis and metabolism of neurotransmitters. Abnormal iron homoeostasis can induce cellular damage through hydroxyl radical production, which can cause the oxidation and modification of lipids, proteins, carbohydrates, and DNA. During ageing, different iron complexes accumulate in brain regions associated with motor and cognitive impairment. In various neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease, changes in iron homoeostasis result in altered cellular iron distribution and accumulation. MRI can often identify these changes, thus providing a potential diagnostic biomarker of neurodegenerative diseases. An important avenue to reduce iron accumulation is the use of iron chelators that are able to cross the blood-brain barrier, penetrate cells, and reduce excessive iron accumulation, thereby affording neuroprotection.
Collapse
Affiliation(s)
- Roberta J Ward
- Centre for Neuroinflammation and Neurodegeneration, Department of Medicine, Hammersmith Hospital Campus, Imperial College London, London, UK; Faculte de Science, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Fabio A Zucca
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate, Milan, Italy
| | - Jeff H Duyn
- Advanced MRI Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Robert R Crichton
- Faculte de Science, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Luigi Zecca
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate, Milan, Italy.
| |
Collapse
|
343
|
Sharma SD, Hernando D, Horng DE, Reeder SB. Quantitative susceptibility mapping in the abdomen as an imaging biomarker of hepatic iron overload. Magn Reson Med 2014; 74:673-83. [PMID: 25199788 DOI: 10.1002/mrm.25448] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Revised: 08/19/2014] [Accepted: 08/20/2014] [Indexed: 01/19/2023]
Abstract
PURPOSE The purpose of this work was to develop and demonstrate feasibility and initial clinical validation of quantitative susceptibility mapping (QSM) in the abdomen as an imaging biomarker of hepatic iron overload. THEORY AND METHODS In general, QSM is faced with the challenges of background field removal and dipole inversion. Respiratory motion, the presence of fat, and severe iron overload further complicate QSM in the abdomen. We propose a technique for QSM in the abdomen that addresses these challenges. Data were acquired from 10 subjects without hepatic iron overload and 33 subjects with known or suspected iron overload. The proposed technique was used to estimate the susceptibility map in the abdomen, from which hepatic iron overload was measured. As a reference, spin-echo data were acquired for R2-based LIC estimation. Liver R2* was measured for correlation with liver susceptibility estimates. RESULTS Correlation between susceptibility and R2-based LIC estimation was R(2) = 0.76 at 1.5 Tesla (T) and R(2) = 0.83 at 3T. Furthermore, high correlation between liver susceptibility and liver R2* (R(2) = 0.94 at 1.5T; R(2) = 0.93 at 3T) was observed. CONCLUSION We have developed and demonstrated initial validation of QSM in the abdomen as an imaging biomarker of hepatic iron overload.
Collapse
Affiliation(s)
- Samir D Sharma
- Department of Radiology, University of Wisconsin, Madison, Wisconsin, USA
| | - Diego Hernando
- Department of Radiology, University of Wisconsin, Madison, Wisconsin, USA
| | - Debra E Horng
- Department of Radiology, University of Wisconsin, Madison, Wisconsin, USA
- Department of Medical Physics, University of Wisconsin, Madison, Wisconsin, USA
| | - Scott B Reeder
- Department of Radiology, University of Wisconsin, Madison, Wisconsin, USA
- Department of Medical Physics, University of Wisconsin, Madison, Wisconsin, USA
- Department of Biomedical Engineering, University of Wisconsin, Madison, Wisconsin, USA
- Department of Medicine, University of Wisconsin, Madison, Wisconsin, USA
| |
Collapse
|
344
|
2D harmonic filtering of MR phase images in multicenter clinical setting: toward a magnetic signature of cerebral microbleeds. Neuroimage 2014; 104:287-300. [PMID: 25149849 DOI: 10.1016/j.neuroimage.2014.08.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 08/10/2014] [Accepted: 08/11/2014] [Indexed: 11/22/2022] Open
Abstract
Cerebral microbleeds (CMBs) have emerged as a new imaging marker of small vessel disease. Composed of hemosiderin, CMBs are paramagnetic and can be detected with MRI sequences sensitive to magnetic susceptibility (typically, gradient recalled echo T2* weighted images). Nevertheless, their identification remains challenging on T2* magnitude images because of confounding structures and lesions. In this context, T2* phase image may play a key role in better characterizing CMBs because of its direct relationship with local magnetic field variations due to magnetic susceptibility difference. To address this issue, susceptibility-based imaging techniques were proposed, such as Susceptibility Weighted Imaging (SWI) and Quantitative Susceptibility Mapping (QSM). But these techniques have not yet been validated for 2D clinical data in multicenter settings. Here, we introduce 2DHF, a fast 2D phase processing technique embedding both unwrapping and harmonic filtering designed for data acquired in 2D, even with slice-to-slice inconsistencies. This method results in internal field maps which reveal local field details due to magnetic inhomogeneity within the region of interest only. This technique is based on the physical properties of the induced magnetic field and should yield consistent results. A synthetic phantom was created for numerical simulations. It simulates paramagnetic and diamagnetic lesions within a 'brain-like' tissue, within a background. The method was evaluated on both this synthetic phantom and multicenter 2D datasets acquired in standardized clinical setting, and compared with two state-of-the-art methods. It proved to yield consistent results on synthetic images and to be applicable and robust on patient data. As a proof-of-concept, we finally illustrate that it is possible to find a magnetic signature of CMBs and CMCs on internal field maps generated with 2DHF on 2D clinical datasets that give consistent results with CT-scans in a subsample of 10 subjects acquired with both modalities.
Collapse
|
345
|
Data distributions in magnetic resonance images: a review. Phys Med 2014; 30:725-41. [PMID: 25059432 DOI: 10.1016/j.ejmp.2014.05.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2013] [Revised: 04/04/2014] [Accepted: 05/01/2014] [Indexed: 11/23/2022] Open
Abstract
Many image processing methods applied to magnetic resonance (MR) images directly or indirectly rely on prior knowledge of the statistical data distribution that characterizes the MR data. Also, data distributions are key in many parameter estimation problems and strongly relate to the accuracy and precision with which parameters can be estimated. This review paper provides an overview of the various distributions that occur when dealing with MR data, considering both single-coil and multiple-coil acquisition systems. The paper also summarizes how knowledge of the MR data distributions can be used to construct optimal parameter estimators and answers the question as to what precision may be achieved ultimately from a particular MR image.
Collapse
|
346
|
Rudko DA, Racosta JM, Kremenchutzky M. Monitoring increased iron levels in multiple sclerosis using MRI. FUTURE NEUROLOGY 2014. [DOI: 10.2217/fnl.14.38] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- David A Rudko
- Department of Physics & Astronomy, Western University, London, ON, N6A 3K7, Canada
- Center for Functional & Metabolic Mapping, Robarts Research Institute, London, ON, N6A 5K8, Canada
| | - Juan M Racosta
- Department of Clinical Neurological Sciences, Western University, London Health Sciences Centre, University Hospital, 339 Windermere Road, London, ON, N6A 5A5, Canada
| | - Marcelo Kremenchutzky
- Department of Clinical Neurological Sciences, Western University, London Health Sciences Centre, University Hospital, 339 Windermere Road, London, ON, N6A 5A5, Canada
| |
Collapse
|
347
|
Bilgic B, Chatnuntawech I, Fan AP, Setsompop K, Cauley SF, Wald LL, Adalsteinsson E. Fast image reconstruction with L2-regularization. J Magn Reson Imaging 2014; 40:181-91. [PMID: 24395184 PMCID: PMC4106040 DOI: 10.1002/jmri.24365] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 07/16/2013] [Indexed: 11/07/2022] Open
Abstract
PURPOSE We introduce L2-regularized reconstruction algorithms with closed-form solutions that achieve dramatic computational speed-up relative to state of the art L1- and L2-based iterative algorithms while maintaining similar image quality for various applications in MRI reconstruction. MATERIALS AND METHODS We compare fast L2-based methods to state of the art algorithms employing iterative L1- and L2-regularization in numerical phantom and in vivo data in three applications; (i) Fast Quantitative Susceptibility Mapping (QSM), (ii) Lipid artifact suppression in Magnetic Resonance Spectroscopic Imaging (MRSI), and (iii) Diffusion Spectrum Imaging (DSI). In all cases, proposed L2-based methods are compared with the state of the art algorithms, and two to three orders of magnitude speed up is demonstrated with similar reconstruction quality. RESULTS The closed-form solution developed for regularized QSM allows processing of a three-dimensional volume under 5 s, the proposed lipid suppression algorithm takes under 1 s to reconstruct single-slice MRSI data, while the PCA based DSI algorithm estimates diffusion propagators from undersampled q-space for a single slice under 30 s, all running in Matlab using a standard workstation. CONCLUSION For the applications considered herein, closed-form L2-regularization can be a faster alternative to its iterative counterpart or L1-based iterative algorithms, without compromising image quality.
Collapse
Affiliation(s)
- Berkin Bilgic
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
- A. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts, USA
| | - Itthi Chatnuntawech
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Audrey P. Fan
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Kawin Setsompop
- A. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
| | - Stephen F. Cauley
- A. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts, USA
| | - Lawrence L. Wald
- A. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
- Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Elfar Adalsteinsson
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
- Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| |
Collapse
|
348
|
Li X, van Zijl PCM. Mean magnetic susceptibility regularized susceptibility tensor imaging (MMSR-STI) for estimating orientations of white matter fibers in human brain. Magn Reson Med 2014; 72:610-9. [PMID: 24974830 DOI: 10.1002/mrm.25322] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 05/24/2014] [Accepted: 05/26/2014] [Indexed: 12/16/2022]
Abstract
PURPOSE An increasing number of studies show that magnetic susceptibility in white matter fibers is anisotropic and may be described by a tensor. However, the limited head rotation possible for in vivo human studies leads to an ill-conditioned inverse problem in susceptibility tensor imaging (STI). Here we suggest the combined use of limiting the susceptibility anisotropy to white matter and imposing morphology constraints on the mean magnetic susceptibility (MMS) for regularizing the STI inverse problem. METHODS The proposed MMS regularized STI (MMSR-STI) method was tested using computer simulations and in vivo human data collected at 3T. The fiber orientation estimated from both the STI and MMSR-STI methods was compared to that from diffusion tensor imaging (DTI). RESULTS Computer simulations show that the MMSR-STI method provides a more accurate estimation of the susceptibility tensor than the conventional STI approach. Similarly, in vivo data show that use of the MMSR-STI method leads to a smaller difference between the fiber orientation estimated from STI and DTI for most selected white matter fibers. CONCLUSION The proposed regularization strategy for STI can improve estimation of the susceptibility tensor in white matter.
Collapse
Affiliation(s)
- Xu Li
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA; Department of Radiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | | |
Collapse
|
349
|
Dimov AV, Liu T, Spincemaille P, Ecanow JS, Tan H, Edelman RR, Wang Y. Joint estimation of chemical shift and quantitative susceptibility mapping (chemical QSM). Magn Reson Med 2014; 73:2100-10. [PMID: 24947227 DOI: 10.1002/mrm.25328] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 05/28/2014] [Accepted: 05/30/2014] [Indexed: 12/12/2022]
Abstract
PURPOSE The purpose of this work is to address the unsolved problem of quantitative susceptibility mapping (QSM) of tissue with fat where both fat and susceptibility change the MR signal phase. THEORY AND METHODS The chemical shift of fat was treated as an additional unknown and was estimated jointly with susceptibility to provide the best data fitting using an automated and iterative algorithm. A simplified susceptibility model was used to calculate an updated value of the chemical shift based on the local magnetic field in each iteration. Numerical simulation, phantom experiments and in vivo imaging were performed. Artifacts were assessed by measuring the susceptibility variance in uniform regions. Accuracy was assessed by comparison with ground truth in simulation, and using a susceptibility matching approach in phantom. RESULTS Using the proposed method, artifacts on the QSM image were markedly suppressed in all tested datasets compared with results generated using fixed chemical shifts. Accuracy of the estimated susceptibility was also improved in numerical simulation and phantom experiments. CONCLUSION A joint estimation of fat content and magnetic susceptibility using an iterative chemical shift update was shown to improve image quality and accuracy on QSM images.
Collapse
Affiliation(s)
- Alexey V Dimov
- Department of Biomedical Engineering, Cornell University, Ithaca, New York, New York, USA.,Department of Radiology, Weill Cornell Medical College, New York, New York, USA
| | - Tian Liu
- Medimagemetric, LLC, New York, New York, USA
| | - Pascal Spincemaille
- Department of Radiology, Weill Cornell Medical College, New York, New York, USA
| | - Jacob S Ecanow
- Department of Radiology, NorthShore University HealthSystem, Evanston, Illinois, USA.,University of Chicago Pritzker School of Medicine, Chicago, Illinois, USA
| | - Huan Tan
- Department of Radiology, NorthShore University HealthSystem, Evanston, Illinois, USA.,Department of Surgery (Neurosurgery), University of Chicago, Chicago, Illinois, USA
| | - Robert R Edelman
- Department of Radiology, NorthShore University HealthSystem, Evanston, Illinois, USA.,Department of Radiology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Yi Wang
- Department of Biomedical Engineering, Cornell University, Ithaca, New York, New York, USA.,Department of Radiology, Weill Cornell Medical College, New York, New York, USA
| |
Collapse
|
350
|
Sun H, Wilman AH. Quantitative susceptibility mapping using single-shot echo-planar imaging. Magn Reson Med 2014; 73:1932-8. [DOI: 10.1002/mrm.25316] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 05/01/2014] [Accepted: 05/22/2014] [Indexed: 01/16/2023]
Affiliation(s)
- Hongfu Sun
- Department of Biomedical Engineering; University of Alberta; Edmonton Canada
| | - Alan H. Wilman
- Department of Biomedical Engineering; University of Alberta; Edmonton Canada
| |
Collapse
|