1
|
Ho CY, Persohn S, Sankar M, Territo PR. Development of Myelin Growth Charts of the White Matter Using T1 Relaxometry. AJNR Am J Neuroradiol 2024:ajnr.A8306. [PMID: 39025639 DOI: 10.3174/ajnr.a8306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 04/02/2024] [Indexed: 07/20/2024]
Abstract
BACKGROUND AND PURPOSE Myelin maturation occurs in late fetal life to early adulthood, with the most rapid changes observed in the first few years of infancy. To quantify the degree of myelination, a specific MR imaging sequence is required to measure the changes in tissue proton relaxivity (R1). R1 positively correlates with the degree of myelination maturation at a given age. Similar to head circumference charts, these data can be used to develop normal growth charts for specific white matter tracts to detect pathologies involving abnormal myelination. MATERIALS AND METHODS This is a cross-sectional study using normal clinical pediatric brain MR images with the MP2RAGE sequence to generate T1 maps. The T1 maps were segmented to 75 brain regions from a brain atlas (white matter and gyri). Statistical modeling for all subjects across regions and the age range was computed, and estimates of population-level percentile ranking were computed to describe the effective myelination rate as a function of age. Test-retest analysis was performed to assess reproducibility. Logistic trendline and regression were performed for selected white matter regions and plotted for growth charts. RESULTS After exclusion for abnormal MR imaging or diseases affecting myelination from the electronic medical record, 103 subject MR images were included, ranging from birth to 17 years of age. Test-retest analysis resulted in a high correlation for white matter (r = 0.88) and gyri (r = 0.95). All white matter regions from the atlas had significant P values for logistic regression with R 2 values ranging from 0.41 to 0.99. CONCLUSIONS These data can serve as a myelination growth chart to permit patient comparisons with normal levels with respect to age and brain regions, thus improving detection of developmental disorders affecting myelin.
Collapse
Affiliation(s)
- Chang Y Ho
- From the Department of Radiology and Imaging Sciences (C.Y.H., P.R.T.), Indiana University School of Medicine, Indianapolis, Indiana
| | - Scott Persohn
- Department of Medicine (S.P., M.S., P.R.T.), Indiana University School of Medicine, Indianapolis, Indiana
| | - Meghana Sankar
- Department of Medicine (S.P., M.S., P.R.T.), Indiana University School of Medicine, Indianapolis, Indiana
| | - Paul R Territo
- From the Department of Radiology and Imaging Sciences (C.Y.H., P.R.T.), Indiana University School of Medicine, Indianapolis, Indiana
- Department of Medicine (S.P., M.S., P.R.T.), Indiana University School of Medicine, Indianapolis, Indiana
- Stark Neuroscience Research Institute (P.R.T.), Indiana University School of Medicine, Indianapolis, Indiana
| |
Collapse
|
2
|
Krienen FM, Levandowski KM, Zaniewski H, del Rosario RC, Schroeder ME, Goldman M, Wienisch M, Lutservitz A, Beja-Glasser VF, Chen C, Zhang Q, Chan KY, Li KX, Sharma J, McCormack D, Shin TW, Harrahill A, Nyase E, Mudhar G, Mauermann A, Wysoker A, Nemesh J, Kashin S, Vergara J, Chelini G, Dimidschstein J, Berretta S, Deverman BE, Boyden E, McCarroll SA, Feng G. A marmoset brain cell census reveals regional specialization of cellular identities. SCIENCE ADVANCES 2023; 9:eadk3986. [PMID: 37824615 PMCID: PMC10569717 DOI: 10.1126/sciadv.adk3986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Accepted: 09/26/2023] [Indexed: 10/14/2023]
Abstract
The mammalian brain is composed of many brain structures, each with its own ontogenetic and developmental history. We used single-nucleus RNA sequencing to sample over 2.4 million brain cells across 18 locations in the common marmoset, a New World monkey primed for genetic engineering, and examined gene expression patterns of cell types within and across brain structures. The adult transcriptomic identity of most neuronal types is shaped more by developmental origin than by neurotransmitter signaling repertoire. Quantitative mapping of GABAergic types with single-molecule FISH (smFISH) reveals that interneurons in the striatum and neocortex follow distinct spatial principles, and that lateral prefrontal and other higher-order cortical association areas are distinguished by high proportions of VIP+ neurons. We use cell type-specific enhancers to drive AAV-GFP and reconstruct the morphologies of molecularly resolved interneuron types in neocortex and striatum. Our analyses highlight how lineage, local context, and functional class contribute to the transcriptional identity and biodistribution of primate brain cell types.
Collapse
Affiliation(s)
- Fenna M. Krienen
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Kirsten M. Levandowski
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Heather Zaniewski
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ricardo C.H. del Rosario
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Margaret E. Schroeder
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Melissa Goldman
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Martin Wienisch
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Alyssa Lutservitz
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Victoria F. Beja-Glasser
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Cindy Chen
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Qiangge Zhang
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ken Y. Chan
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Katelyn X. Li
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Jitendra Sharma
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Dana McCormack
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Tay Won Shin
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Howard Hughes Medical Institute, Cambridge, MA 02139, USA
| | - Andrew Harrahill
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Eric Nyase
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Gagandeep Mudhar
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08544, USA
| | - Abigail Mauermann
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Howard Hughes Medical Institute, Cambridge, MA 02139, USA
| | - Alec Wysoker
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - James Nemesh
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Seva Kashin
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Josselyn Vergara
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Gabriele Chelini
- Center for Mind/Brain Sciences, University of Trento, Piazza della Manifattura n.1, Rovereto (TN) 38068, Italy
| | - Jordane Dimidschstein
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Sabina Berretta
- Basic Neuroscience Division, McLean Hospital, Belmont, MA 02478, USA
- Department of Psychiatry, Harvard Medical School, Boston, MA 02115, USA
| | - Benjamin E. Deverman
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Ed Boyden
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Howard Hughes Medical Institute, Cambridge, MA 02139, USA
| | - Steven A. McCarroll
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Guoping Feng
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| |
Collapse
|
3
|
Reynolds LA, Morris SR, Vavasour IM, Barlow L, Laule C, MacKay AL, Michal CA. Nonaqueous magnetization following adiabatic and selective pulses in brain: T1 and cross-relaxation dynamics. NMR IN BIOMEDICINE 2023:e4936. [PMID: 36973767 DOI: 10.1002/nbm.4936] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 03/03/2023] [Accepted: 03/20/2023] [Indexed: 06/18/2023]
Abstract
Inversion pulses are commonly employed in MRI for T 1 $$ {T}_1 $$ -weighted contrast and relaxation measurements. In the brain, it is often assumed that adiabatic pulses saturate the nonaqueous magnetization. We investigated this assumption using solid-state NMR to monitor the nonaqueous signal directly following adiabatic inversion and compared this with signals following hard and soft inversion pulses. The effects of the different preparations on relaxation dynamics were explored. Inversion recovery experiments were performed on ex vivo bovine and porcine brains using 360-MHz (8.4 T) and 200-MHz (4.7 T) NMR spectrometers, respectively, using broadband rectangular, adiabatic, and sinc inversion pulses as well as a long rectangular saturation pulse. Analogous human brain MRI experiments were performed at 3 T using single-slice echo-planar imaging. Relaxation data were fitted by mono- and biexponential decay models. Further fitting analysis was performed using only two inversion delay times. Adiabatic and sinc inversion left much of the nonaqueous magnetization along B 0 $$ {B}_0 $$ and resulted in biexponential relaxation. Saturation of both aqueous and nonaqueous magnetization components led to effectively monoexponential T 1 $$ {T}_1 $$ relaxation. Typical adiabatic inversion pulses do not, as has been widely assumed, saturate the nonaqueous proton magnetization in white matter. Unequal magnetization states in aqueous and nonaqueous 1 H reservoirs prepared by soft and adiabatic pulses result in biexponential T 1 $$ {T}_1 $$ relaxation. Both pools must be prepared in the same magnetization state (e.g., saturated or inverted) in order to observe consistent monoexponential relaxation.
Collapse
Affiliation(s)
- Luke A Reynolds
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada
| | - Sarah R Morris
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada
- Department of Radiology, University of British Columbia, Vancouver, BC, Canada
- International Collaboration on Repair Discoveries, Blusson Spinal Cord Centre, University of British Columbia, Vancouver, BC, Canada
| | - Irene M Vavasour
- Department of Radiology, University of British Columbia, Vancouver, BC, Canada
- International Collaboration on Repair Discoveries, Blusson Spinal Cord Centre, University of British Columbia, Vancouver, BC, Canada
- UBC MRI Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Laura Barlow
- UBC MRI Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Cornelia Laule
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada
- Department of Radiology, University of British Columbia, Vancouver, BC, Canada
- International Collaboration on Repair Discoveries, Blusson Spinal Cord Centre, University of British Columbia, Vancouver, BC, Canada
- Department of Pathology & Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Alex L MacKay
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada
- Department of Radiology, University of British Columbia, Vancouver, BC, Canada
- UBC MRI Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Carl A Michal
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada
| |
Collapse
|
4
|
High-resolution magnetization-transfer imaging of post-mortem marmoset brain: Comparisons with relaxometry and histology. Neuroimage 2023; 268:119860. [PMID: 36610679 DOI: 10.1016/j.neuroimage.2023.119860] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 12/28/2022] [Accepted: 01/03/2023] [Indexed: 01/07/2023] Open
Abstract
Cell membranes and macromolecules or paramagnetic compounds interact with water proton spins, which modulates magnetic resonance imaging (MRI) contrast providing information on tissue composition. For a further investigation, quantitative magnetization transfer (qMT) parameters (at 3T), including the ratio of the macromolecular and water proton pools, F, and the exchange-rate constant as well as the (observed) longitudinal and the effective transverse relaxation rates (at 3T and 7T), R1obs and R2*, respectively, were measured at high spatial resolution (200 µm) in a slice of fixed marmoset brain and compared to histology results obtained with Gallyas' myelin stain and Perls' iron stain. R1obs and R2* were linearly correlated with the iron content for the entire slice, whereas distinct differences were obtained between gray and white matter for correlations of relaxometry and qMT parameters with myelin content. The combined results suggest that the macromolecular pool interacting with water consists of myelin and (less efficient) non-myelin contributions. Despite strong correlation of F and R1obs, none of these parameters was uniquely specific to myelination. Due to additional sensitivity to iron stores, R1obs and R2* were more sensitive for depicting microstructural differences between cortical layers than F.
Collapse
|
5
|
Correlation analysis between the complex electrical permittivity and relaxation time of tissue mimicking phantoms in 7 T MRI. Sci Rep 2022; 12:15444. [PMID: 36104392 PMCID: PMC9474530 DOI: 10.1038/s41598-022-19832-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 09/05/2022] [Indexed: 12/04/2022] Open
Abstract
Dielectric relaxation theory describes the complex permittivity of a material in an alternating field; in particular, Debye theory relates the time it takes for an applied field to achieve the maximum polarization and the electrical properties of the material. Although, Debye’s equations were proposed for electrical polarization, in this study, we investigate the correlation between the magnetic longitudinal relaxation time T1 and the complex electrical permittivity of tissue-mimicking phantoms using a 7 T magnetic resonance scanner. We created phantoms that mimicked several human tissues with specific electrical properties. The electrical properties of the phantoms were measured using bench-test equipment. T1 values were acquired from phantoms using MRI. The measured values were fitted with functions based on dielectric estimations, using relaxation times of electrical polarization, and the mixture theory for dielectrics. The results show that, T1 and the real permittivity are correlated; therefore, the correlation can be approximated with a rational function in the case of water-based phantoms. The correlation between index loss and T1 was determined using a fitting function based on the Debye equation and mixture theory equation, in which the fraction of the materials was taken into account. This phantom study and analysis provide an insight into the application relaxation times used for estimating dielectric properties. Currently, the measurement of electrical properties based on dielectric relaxation theory is based on an antenna, sometimes invasive, that irradiates an electric field into a small sample; thus, it is not possible to create a map of electrical properties for a complex structure such as the human body. This study could be further used to compute the electrical properties maps of tissues by scanning images and measuring T1 maps.
Collapse
|
6
|
Frye BM, Craft S, Register TC, Kim J, Whitlow CT, Barcus RA, Lockhart SN, Sai KKS, Shively CA. Early Alzheimer's disease-like reductions in gray matter and cognitive function with aging in nonhuman primates. ALZHEIMER'S & DEMENTIA (NEW YORK, N. Y.) 2022; 8:e12284. [PMID: 35310523 PMCID: PMC8918111 DOI: 10.1002/trc2.12284] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 12/24/2021] [Accepted: 02/15/2022] [Indexed: 01/13/2023]
Abstract
Introduction Age-related neuropathology associated with sporadic Alzheimer's disease (AD) often develops well before the onset of symptoms. Given AD's long preclinical period, translational models are needed to identify early signatures of pathological decline. Methods Using structural magnetic resonance imaging and cognitive assessments, we examined the relationships among age, cognitive performance, and neuroanatomy in 48 vervet monkeys (Chlorocebus aethiops sabaeus) ranging from young adults to very old. Results We found negative associations of age with cortical gray matter volume (P = .003) and the temporal-parietal cortical thickness meta-region of interest (P = .001). Additionally, cortical gray matter volumes predicted working memory at approximately 1-year follow-up (correct trials at the 20s delay [P = .008]; correct responses after longer delays [P = .004]). Discussion Cortical gray matter diminishes with age in vervets in regions relevant to AD, which may increase risk of cognitive impairment. This study lays the groundwork for future investigations to test therapeutics to delay or slow pathological decline.
Collapse
Affiliation(s)
- Brett M. Frye
- Department of Pathology/Comparative MedicineWake Forest School of MedicineWinston‐SalemNorth CarolinaUSA
| | - Suzanne Craft
- Department of Internal Medicine/GerontologyWake Forest School of MedicineWinston‐SalemNorth CarolinaUSA
- Wake Forest Alzheimer's Disease Research CenterWinston‐SalemNorth CarolinaUSA
| | - Thomas C. Register
- Department of Pathology/Comparative MedicineWake Forest School of MedicineWinston‐SalemNorth CarolinaUSA
- Wake Forest Alzheimer's Disease Research CenterWinston‐SalemNorth CarolinaUSA
| | - Jeongchul Kim
- Wake Forest Alzheimer's Disease Research CenterWinston‐SalemNorth CarolinaUSA
- Department of RadiologyWake Forest School of MedicineWinston‐SalemNorth CarolinaUSA
| | - Christopher T. Whitlow
- Wake Forest Alzheimer's Disease Research CenterWinston‐SalemNorth CarolinaUSA
- Department of RadiologyWake Forest School of MedicineWinston‐SalemNorth CarolinaUSA
| | - Richard A. Barcus
- Wake Forest Alzheimer's Disease Research CenterWinston‐SalemNorth CarolinaUSA
- Department of RadiologyWake Forest School of MedicineWinston‐SalemNorth CarolinaUSA
| | - Samuel N. Lockhart
- Department of Internal Medicine/GerontologyWake Forest School of MedicineWinston‐SalemNorth CarolinaUSA
- Wake Forest Alzheimer's Disease Research CenterWinston‐SalemNorth CarolinaUSA
| | - Kiran Kumar Solingapuram Sai
- Wake Forest Alzheimer's Disease Research CenterWinston‐SalemNorth CarolinaUSA
- Department of RadiologyWake Forest School of MedicineWinston‐SalemNorth CarolinaUSA
| | - Carol A. Shively
- Department of Pathology/Comparative MedicineWake Forest School of MedicineWinston‐SalemNorth CarolinaUSA
- Wake Forest Alzheimer's Disease Research CenterWinston‐SalemNorth CarolinaUSA
| |
Collapse
|
7
|
Song R, Glass JO, Reddick WE. Modified Diffusion Tensor Image Processing Pipeline for Archived Studies of Patients With Leukoencephalopathy. J Magn Reson Imaging 2021; 54:997-1008. [PMID: 33856092 DOI: 10.1002/jmri.27636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 03/26/2021] [Accepted: 03/30/2021] [Indexed: 11/05/2022] Open
Abstract
BACKGROUND In archived diffusion tensor imaging (DTI) studies, a reversed-phase encoding (PE) scan required to correct the distortion in single-shot echo-planar imaging (EPI) may not have been acquired. Furthermore, DTI tractography is adversely affected by incorrect white matter segmentation due to leukoencephalopathy (LE). All these issues need to be addressed. PURPOSE To propose and evaluate a modified DTI processing pipeline with DIstortion COrrection using pseudo T2 -weighted images (DICOT) to overcome limitations in existing acquisition protocols. STUDY TYPE Retrospective feasibility. SUBJECTS DICOT was assessed in simulated data and 84 acute lymphoblastic leukemia (ALL) patients with reversed PE acquired. The pipeline was then tested in 522 scans from 261 ALL patients without a reversed PE acquired. FIELD STRENGTH/SEQUENCE A 3 T; diffusion-weighted EPI; 3D magnetization prepared rapid acquisition gradient echo (MPRAGE). STATISTICAL TESTS Repeated measures analysis of variance and Tukey post hoc tests were performed to compare fractional anisotropy (FA) values obtained by different methods. ASSESSMENT FA and corresponding absolute error maps were obtained using TOPUP, DICOT, INVERSION (Inverse contrast Normalization for VERy Simple registratION) and NO CORR (no correction). Each method was assessed by comparing to TOPUP. The pipeline in the ALL patients was evaluated based on the failure rate of the distortion correction using the global correlation values. RESULTS Using DICOT reduced the mean absolute errors by an average of 32% in FA in simulation datasets. In 84 patients, the error reductions were approximately 15% in FA with DICOT, while it was 5% with INVERSION. No significant differences between the TOPUP and DICOT were observed in FA with P = 0.090/0.894(AP/PA). Only 15 of 516 examinations requiring any additional manual intervention. CONCLUSION This modified pipeline produced better results than the INVERSION. Furthermore, robust performance was demonstrated in archived patient scans acquired without an inverse PE necessary for TOPUP correction. EVIDENCE LEVEL 3 TECHNICAL EFFICACY: Stage 2.
Collapse
Affiliation(s)
- Ruitian Song
- Department of Diagnostic Imaging, St Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - John O Glass
- Department of Diagnostic Imaging, St Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Wilburn E Reddick
- Department of Diagnostic Imaging, St Jude Children's Research Hospital, Memphis, Tennessee, USA
| |
Collapse
|
8
|
Lacreuse A, Raz N, Schmidtke D, Hopkins WD, Herndon JG. Age-related decline in executive function as a hallmark of cognitive ageing in primates: an overview of cognitive and neurobiological studies. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190618. [PMID: 32951543 DOI: 10.1098/rstb.2019.0618] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Executive function (EF) is a complex construct that reflects multiple higher-order cognitive processes such as planning, updating, inhibiting and set-shifting. Decline in these functions is a hallmark of cognitive ageing in humans, and age differences and changes in EF correlate with age-related differences and changes in association cortices, particularly the prefrontal areas. Here, we review evidence for age-related decline in EF and associated neurobiological changes in prosimians, New World and Old World monkeys, apes and humans. While EF declines with age in all primate species studied, the relationship of this decline with age-related alterations in the prefrontal cortex remains unclear, owing to the scarcity of neurobiological studies focusing on the ageing brain in most primate species. In addition, the influence of sex, vascular and metabolic risk, and hormonal status has rarely been considered. We outline several methodological limitations and challenges with the goal of producing a comprehensive integration of cognitive and neurobiological data across species and elucidating how ageing shapes neurocognitive trajectories in primates with different life histories, lifespans and brain architectures. Such comparative investigations are critical for fostering translational research and understanding healthy and pathological ageing in our own species. This article is part of the theme issue 'Evolution of the primate ageing process'.
Collapse
Affiliation(s)
- Agnès Lacreuse
- Psychological and Brain Sciences, University of Massachusetts, Tobin Hall, 135 Hicks Way, Amherst, MA 01003, USA
| | - Naftali Raz
- Department of Psychology, Wayne State University, Detroit, MI, USA.,Max Planck Institute for Human Development, Berlin, Germany
| | - Daniel Schmidtke
- University of Veterinary Medicine, Foundation, Hannover, Germany
| | - William D Hopkins
- Keeling Center for Comparative Medicine and Research, University of Texas, MD Anderson Cancer Center, Bastrop, TX, USA
| | - James G Herndon
- Department of Psychology, Emory University, Atlanta, GA, USA
| |
Collapse
|
9
|
Deruelle T, Kober F, Perles-Barbacaru A, Delzescaux T, Noblet V, Barbier EL, Dojat M. A Multicenter Preclinical MRI Study: Definition of Rat Brain Relaxometry Reference Maps. Front Neuroinform 2020; 14:22. [PMID: 32508614 PMCID: PMC7248563 DOI: 10.3389/fninf.2020.00022] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 04/21/2020] [Indexed: 11/13/2022] Open
Abstract
Similarly to human population imaging, there are several well-founded motivations for animal population imaging, the most notable being the improvement of the validity of statistical results by pooling a sufficient number of animal data provided by different imaging centers. In this paper, we demonstrate the feasibility of such a multicenter animal study, sharing raw data from forty rats and processing pipelines between four imaging centers. As specific use case, we focused on T1 and T2 mapping of the healthy rat brain at 7T. We quantitatively report about the variability observed across two MR data providers and evaluate the influence of image processing steps on the final maps, using three fitting algorithms from three centers. Finally, to derive relaxation times from different brain areas, two multi-atlas segmentation pipelines from different centers were performed on two different platforms. Differences between the two data providers were 2.21% for T1 and 9.52% for T2. Differences between processing pipelines were 1.04% for T1 and 3.33% for T2. These maps, obtained in healthy conditions, may be used in the future as reference when exploring alterations in animal models of pathology.
Collapse
Affiliation(s)
- Tristan Deruelle
- INSERM, U1216, Grenoble Institut des Neurosciences, Université Grenoble Alpes, Grenoble, France
| | - Frank Kober
- CNRS, CRMBM, Aix-Marseille Université, Marseille, France
| | | | | | - Vincent Noblet
- CNRS, ICube - IMAGeS, Strasbourg University, Strasbourg, France
| | - Emmanuel L Barbier
- INSERM, U1216, Grenoble Institut des Neurosciences, Université Grenoble Alpes, Grenoble, France
| | - Michel Dojat
- INSERM, U1216, Grenoble Institut des Neurosciences, Université Grenoble Alpes, Grenoble, France
| |
Collapse
|
10
|
Lin MK, Takahashi YS, Huo BX, Hanada M, Nagashima J, Hata J, Tolpygo AS, Ram K, Lee BC, Miller MI, Rosa MGP, Sasaki E, Iriki A, Okano H, Mitra P. A high-throughput neurohistological pipeline for brain-wide mesoscale connectivity mapping of the common marmoset. eLife 2019; 8:e40042. [PMID: 30720427 PMCID: PMC6384052 DOI: 10.7554/elife.40042] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 02/04/2019] [Indexed: 11/13/2022] Open
Abstract
Understanding the connectivity architecture of entire vertebrate brains is a fundamental but difficult task. Here we present an integrated neuro-histological pipeline as well as a grid-based tracer injection strategy for systematic mesoscale connectivity mapping in the common marmoset (Callithrix jacchus). Individual brains are sectioned into ~1700 20 µm sections using the tape transfer technique, permitting high quality 3D reconstruction of a series of histochemical stains (Nissl, myelin) interleaved with tracer labeled sections. Systematic in-vivo MRI of the individual animals facilitates injection placement into reference-atlas defined anatomical compartments. Further, by combining the resulting 3D volumes, containing informative cytoarchitectonic markers, with in-vivo and ex-vivo MRI, and using an integrated computational pipeline, we are able to accurately map individual brains into a common reference atlas despite the significant individual variation. This approach will facilitate the systematic assembly of a mesoscale connectivity matrix together with unprecedented 3D reconstructions of brain-wide projection patterns in a primate brain.
Collapse
Affiliation(s)
- Meng Kuan Lin
- Laboratory for Marmoset Neural ArchitectureRIKEN Center for Brain ScienceWakoJapan
| | | | - Bing-Xing Huo
- Laboratory for Marmoset Neural ArchitectureRIKEN Center for Brain ScienceWakoJapan
| | - Mitsutoshi Hanada
- Laboratory for Marmoset Neural ArchitectureRIKEN Center for Brain ScienceWakoJapan
| | - Jaimi Nagashima
- Laboratory for Marmoset Neural ArchitectureRIKEN Center for Brain ScienceWakoJapan
| | - Junichi Hata
- Laboratory for Marmoset Neural ArchitectureRIKEN Center for Brain ScienceWakoJapan
| | | | | | - Brian C Lee
- Center for Imaging ScienceJohns Hopkins UniversityMarylandUnited States
| | - Michael I Miller
- Center for Imaging ScienceJohns Hopkins UniversityMarylandUnited States
| | - Marcello GP Rosa
- Department of Physiology and Biomedicine, Discovery InstituteMonash UniversityMelbourneAustralia
- Australian Research Council Centre of Excellence for Integrative Brain FunctionClaytonAustralia
| | - Erika Sasaki
- Central Institute for Experimental AnimalsKawasakiJapan
| | - Atsushi Iriki
- Laboratory for Symbolic Cognitive DevelopmentRIKEN Center for Brain ScienceWakoJapan
| | - Hideyuki Okano
- Laboratory for Marmoset Neural ArchitectureRIKEN Center for Brain ScienceWakoJapan
- Department of PhysiologyKeio University School of MedicineTokyoJapan
| | - Partha Mitra
- Laboratory for Marmoset Neural ArchitectureRIKEN Center for Brain ScienceWakoJapan
- Cold Spring Harbor LaboratoryCold Spring HarborUnited States
| |
Collapse
|
11
|
Haast RAM, Ivanov D, Uludağ K. The impact of B1+ correction on MP2RAGE cortical T 1 and apparent cortical thickness at 7T. Hum Brain Mapp 2018; 39:2412-2425. [PMID: 29457319 PMCID: PMC5969159 DOI: 10.1002/hbm.24011] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 02/09/2018] [Accepted: 02/10/2018] [Indexed: 01/06/2023] Open
Abstract
Determination of cortical thickness using MRI has often been criticized due to the presence of various error sources. Specifically, anatomical MRI relying on T1 contrast may be unreliable due to spatially variable image contrast between gray matter (GM), white matter (WM) and cerebrospinal fluid (CSF). Especially at ultra‐high field (≥ 7T) MRI, transmit and receive B1‐related image inhomogeneities can hamper correct classification of tissue types. In the current paper, we demonstrate that residual
B1+ (transmit) inhomogeneities in the T1‐weighted and quantitative T1 images using the MP2RAGE sequence at 7T lead to biases in cortical thickness measurements. As expected, post‐hoc correction for the spatially varying
B1+ profile reduced the apparent T1 values across the cortex in regions with low
B1+, and slightly increased apparent T1 in regions with high
B1+. As a result, improved contrast‐to‐noise ratio both at the GM‐CSF and GM‐WM boundaries can be observed leading to more accurate surface reconstructions and cortical thickness estimates. Overall, the changes in cortical thickness ranged between a 5% decrease to a 70% increase after
B1+ correction, reducing the variance of cortical thickness values across the brain dramatically and increasing the comparability with normative data. More specifically, the cortical thickness estimates increased in regions characterized by a strong decrease of apparent T1 after
B1+ correction in regions with low
B1+ due to improved detection of the pial surface. The current results suggest that cortical thickness can be more accurately determined using MP2RAGE data at 7T if
B1+ inhomogeneities are accounted for.
Collapse
Affiliation(s)
- Roy A M Haast
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands.,Maastricht Centre for Systems Biology, Maastricht University, Maastricht, Netherlands
| | - Dimo Ivanov
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Kâmil Uludağ
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands
| |
Collapse
|
12
|
Sveinsson B, Chaudhari AS, Gold GE, Hargreaves BA. A simple analytic method for estimating T2 in the knee from DESS. Magn Reson Imaging 2016; 38:63-70. [PMID: 28017730 DOI: 10.1016/j.mri.2016.12.018] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 12/19/2016] [Accepted: 12/20/2016] [Indexed: 11/16/2022]
Abstract
PURPOSE To introduce a simple analytical formula for estimating T2 from a single Double-Echo in Steady-State (DESS) scan. METHODS Extended Phase Graph (EPG) modeling was used to develop a straightforward linear approximation of the relationship between the two DESS signals, enabling accurate T2 estimation from one DESS scan. Simulations were performed to demonstrate cancellation of different echo pathways to validate this simple model. The resulting analytic formula was compared to previous methods for T2 estimation using DESS and fast spin-echo scans in agar phantoms and knee cartilage in three volunteers and three patients. The DESS approach allows 3D (256×256×44) T2-mapping with fat suppression in scan times of 3-4min. RESULTS The simulations demonstrated that the model approximates the true signal very well. If the T1 is within 20% of the assumed T1, the T2 estimation error was shown to be less than 5% for typical scans. The inherent residual error in the model was demonstrated to be small both due to signal decay and opposing signal contributions. The estimated T2 from the linear relationship agrees well with reference scans, both for the phantoms and in vivo. The method resulted in less underestimation of T2 than previous single-scan approaches, with processing times 60 times faster than using a numerical fit. CONCLUSION A simplified relationship between the two DESS signals allows for rapid 3D T2 quantification with DESS that is accurate, yet also simple. The simplicity of the method allows for immediate T2 estimation in cartilage during the MRI examination.
Collapse
Affiliation(s)
- B Sveinsson
- Department of Radiology, Stanford University, Stanford, CA, United States.
| | - A S Chaudhari
- Department of Radiology, Stanford University, Stanford, CA, United States
| | - G E Gold
- Department of Radiology, Stanford University, Stanford, CA, United States
| | - B A Hargreaves
- Department of Radiology, Stanford University, Stanford, CA, United States
| |
Collapse
|
13
|
Silva AC. Anatomical and functional neuroimaging in awake, behaving marmosets. Dev Neurobiol 2016; 77:373-389. [PMID: 27706916 DOI: 10.1002/dneu.22456] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 09/28/2016] [Accepted: 09/28/2016] [Indexed: 12/12/2022]
Abstract
The common marmoset (Callithrix jacchus) is a small New World monkey that has gained significant recent interest in neuroscience research, not only because of its compatibility with gene editing techniques, but also due to its tremendous versatility as an experimental animal model. Neuroimaging modalities, including anatomical (MRI) and functional magnetic resonance imaging (fMRI), complemented by two-photon laser scanning microscopy and electrophysiology, have been at the forefront of unraveling the anatomical and functional organization of the marmoset brain. High-resolution anatomical MRI of the marmoset brain can be obtained with remarkable cytoarchitectonic detail. Functional MRI of the marmoset brain has been used to study various sensory systems, including somatosensory, auditory, and visual pathways, while resting-state fMRI studies have unraveled functional brain networks that bear great correspondence to those previously described in humans. Two-photon laser scanning microscopy of the marmoset brain has enabled the simultaneous recording of neuronal activity from thousands of neurons with single cell spatial resolution. In this article, we aim to review the main results obtained by our group and by our colleagues in applying neuroimaging techniques to study the marmoset brain. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 373-389, 2017.
Collapse
Affiliation(s)
- Afonso C Silva
- Cerebral Microcirculation Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892
| |
Collapse
|
14
|
Driencourt L, Romero CJ, Lepore M, Eggenschwiler F, Reynaud O, Just N. T 1 mapping of the mouse brain following fractionated manganese administration using MP2RAGE. Brain Struct Funct 2016; 222:201-214. [PMID: 27000066 DOI: 10.1007/s00429-016-1211-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Accepted: 03/03/2016] [Indexed: 10/22/2022]
Abstract
With the increasing development of transgenic mouse models of neurodegenerative diseases allowing improved understanding of the underlying mechanisms of these disorders, robust quantitative mapping techniques are also needed in rodents. MP2RAGE has shown great potential for structural imaging in humans at high fields. In the present work, MP2RAGE was successfully implemented at 9.4T and 14.1T. Following fractionated injections of MnCl2, MP2RAGE images were acquired allowing simultaneous depiction and T1 mapping of structures in the mouse brain at both fields. In addition, T1 maps demonstrated significant T1 shortenings in different structures of the mouse brain (p < 0.0008 at 9.4T, p < 0.000001 at 14.1T). T1 values recovered to the levels of saline-injected animals 1 month after the last injection except in the pituitary gland. We believe that MP2RAGE represents an important prospective translational tool for further structural MRI.
Collapse
Affiliation(s)
- Luc Driencourt
- CIBM-AIT Core, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | | | - Mario Lepore
- CIBM-AIT Core, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | | | - Olivier Reynaud
- CIBM-AIT Core, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Nathalie Just
- CIBM-AIT Core, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland. .,Institut für Klinische Radiologie, Translational Research Imaging Center (TRIC), Albert-Schweitzer-Campus 1, Gebäude A16, Anfahrt: Waldeyerstr. 1, 48149, Münster, Germany.
| |
Collapse
|
15
|
Didier ES, MacLean AG, Mohan M, Didier PJ, Lackner AA, Kuroda MJ. Contributions of Nonhuman Primates to Research on Aging. Vet Pathol 2016; 53:277-90. [PMID: 26869153 PMCID: PMC5027759 DOI: 10.1177/0300985815622974] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Aging is the biological process of declining physiologic function associated with increasing mortality rate during advancing age. Humans and higher nonhuman primates exhibit unusually longer average life spans as compared with mammals of similar body mass. Furthermore, the population of humans worldwide is growing older as a result of improvements in public health, social services, and health care systems. Comparative studies among a wide range of organisms that include nonhuman primates contribute greatly to our understanding about the basic mechanisms of aging. Based on their genetic and physiologic relatedness to humans, nonhuman primates are especially important for better understanding processes of aging unique to primates, as well as for testing intervention strategies to improve healthy aging and to treat diseases and disabilities in older people. Rhesus and cynomolgus macaques are the predominant monkeys used in studies on aging, but research with lower nonhuman primate species is increasing. One of the priority topics of research about aging in nonhuman primates involves neurologic changes associated with cognitive decline and neurodegenerative diseases. Additional areas of research include osteoporosis, reproductive decline, caloric restriction, and their mimetics, as well as immune senescence and chronic inflammation that affect vaccine efficacy and resistance to infections and cancer. The purpose of this review is to highlight the findings from nonhuman primate research that contribute to our understanding about aging and health span in humans.
Collapse
Affiliation(s)
- E S Didier
- Division of Microbiology, Tulane National Primate Research Center, Covington, LA, USA
| | - A G MacLean
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, LA, USA
| | - M Mohan
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, LA, USA
| | - P J Didier
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, LA, USA
| | - A A Lackner
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, LA, USA
| | - M J Kuroda
- Division of Immunology, Tulane National Primate Research Center, Covington, LA, USA
| |
Collapse
|
16
|
Lacreuse A, Mong JA, Hara Y. Neurocognitive effects of estrogens across the adult lifespan in nonhuman primates: State of knowledge and new perspectives. Horm Behav 2015; 74:157-66. [PMID: 25762288 DOI: 10.1016/j.yhbeh.2015.03.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 02/26/2015] [Accepted: 03/02/2015] [Indexed: 01/29/2023]
Abstract
This article is part of a Special Issue "Estradiol and cognition". This review discusses the unique contribution of nonhuman primate research to our understanding of the neurocognitive effects of estrogens throughout the adult lifespan in females. Mounting evidence indicates that estrogens affect many aspects of hippocampal, prefrontal and cholinergic function in the primate brain and the underlying mechanisms are beginning to be elucidated. In addition, estrogens may also influence cognitive function indirectly, via the modulation of other systems that impact cognition. We will focus on the effects of estrogens on sleep and emphasize the need for primate models to better understand these complex interactions. Continued research with nonhuman primates is essential for the development of therapies that are optimal for the maintenance of women's cognitive health throughout the lifespan.
Collapse
Affiliation(s)
- Agnès Lacreuse
- Department of Psychological and Brain Sciences, University of Massachusetts at Amherst, MA, USA.
| | - Jessica A Mong
- Department of Pharmacology, University of Maryland, School of Medicine, Baltimore, MD, USA
| | - Yuko Hara
- Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| |
Collapse
|
17
|
Rioux JA, Levesque IR, Rutt BK. Biexponential longitudinal relaxation in white matter: Characterization and impact on T1 mapping with IR-FSE and MP2RAGE. Magn Reson Med 2015; 75:2265-77. [PMID: 26190230 DOI: 10.1002/mrm.25729] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 03/18/2015] [Accepted: 03/21/2015] [Indexed: 12/19/2022]
Abstract
PURPOSE Magnetization transfer in white matter (WM) causes biexponential relaxation, but most quantitative T1 measurements fit data assuming monoexponential relaxation. The resulting monoexponential T1 estimate varies based on scan parameters and represents a source of variation between studies, especially at high fields. In this study, we characterized WM T1 relaxation and performed simulations to determine how to minimize this deviation. METHODS To characterize biexponential relaxation, four volunteers were scanned at 3T and 7T using inversion recovery fast spin echo (IR-FSE) with 13 inversion times (TIs). Three volunteers were scanned with IR-FSE using TIs chosen by simulations to reduce T1 deviation, and with MP2RAGE. RESULTS At 3T, the biexponential relaxation has a short component of T1 = 48 ms (9%) and a long component of T1 = 939 ms. At 7T the short component is T1 = 57 ms (11%) and the long component is 1349 ms (89%). For IR-FSE, acquiring four TIs with a minimum of 150 ms (3T) or 200 ms (7T) yielded monoexponential T1 estimates that match the long component to within 10 ms. For MP2RAGE, significant differences (90 ms at 3T, 125 ms at 7T) remain at all parameter values. CONCLUSION Many T1 mapping sequences yield robust estimates of the long T1 component with suitable choice of TIs, allowing reproducible, sequence-independent T1 values to be measured. However, this is not true of MP2RAGE in its current implementation. Magn Reson Med 75:2265-2277, 2016. © 2015 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- James A Rioux
- Department of Radiology, Stanford University, Stanford, California, USA
| | - Ives R Levesque
- Department of Radiology, Stanford University, Stanford, California, USA.,Medical Physics Unit, McGill University, Montreal, Quebec, Canada.,Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - Brian K Rutt
- Department of Radiology, Stanford University, Stanford, California, USA
| |
Collapse
|
18
|
Anderson VC, Obayashi JT, Kaye JA, Quinn JF, Berryhill P, Riccelli LP, Peterson D, Rooney WD. Longitudinal relaxographic imaging of white matter hyperintensities in the elderly. Fluids Barriers CNS 2014; 11:24. [PMID: 25379172 PMCID: PMC4209516 DOI: 10.1186/2045-8118-11-24] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 10/04/2014] [Indexed: 11/25/2022] Open
Abstract
Background Incidental white matter hyperintensities (WMHs) are common findings on T2-weighted magnetic resonance images of the aged brain and have been associated with cognitive decline. While a variety of pathogenic mechanisms have been proposed, the origin of WMHs and the extent to which lesions in the deep and periventricular white matter reflect distinct etiologies remains unclear. Our aim was to quantify the fractional blood volume (vb) of small WMHs in vivo using a novel magnetic resonance imaging (MRI) approach and examine the contribution of blood–brain barrier disturbances to WMH formation in the deep and periventricular white matter. Methods Twenty-three elderly volunteers (aged 59–82 years) underwent 7 Tesla relaxographic imaging and fluid-attenuated inversion recovery (FLAIR) MRI. Maps of longitudinal relaxation rate constant (R1) were prepared before contrast reagent (CR) injection and throughout CR washout. Voxelwise estimates of vb were determined by fitting temporal changes in R1 values to a two-site model that incorporates the effects of transendothelial water exchange. Average vb values in deep and periventricular WMHs were determined after semi-automated segmentation of FLAIR images. Ventricular permeability was estimated from the change in CSF R1 values during CR washout. Results In the absence of CR, the total water fraction in both deep and periventricular WMHs was increased compared to normal appearing white matter (NAWM). The vb of deep WMHs was 1.8 ± 0.6 mL/100 g and was significantly reduced compared to NAWM (2.4 ± 0.8 mL/100 g). In contrast, the vb of periventricular WMHs was unchanged compared to NAWM, decreased with ventricular volume and showed a positive association with ventricular permeability. Conclusions Hyperintensities in the deep WM appear to be driven by vascular compromise, while those in the periventricular WM are most likely the result of a compromised ependyma in which the small vessels remain relatively intact. These findings support varying contributions of blood–brain barrier and brain-CSF interface disturbances in the pathophysiology of deep and periventricular WMHs in the aged human brain.
Collapse
Affiliation(s)
- Valerie C Anderson
- Advanced Imaging Research Center, L452, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA
| | - James T Obayashi
- Department of Neurological Surgery, Oregon Health & Science University, Portland, OR, USA
| | - Jeffrey A Kaye
- Department of Neurology, Oregon Health & Science University, Portland, OR, USA
| | - Joseph F Quinn
- Department of Neurology, Oregon Health & Science University, Portland, OR, USA
| | | | - Louis P Riccelli
- Department of Diagnostic Radiology, Oregon Health & Science University, Portland, OR, USA
| | - Dean Peterson
- Department of Neurological Surgery, Oregon Health & Science University, Portland, OR, USA
| | - William D Rooney
- Advanced Imaging Research Center, L452, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA
| |
Collapse
|
19
|
Maggi P, Macri SMC, Gaitán MI, Leibovitch E, Wholer JE, Knight HL, Ellis M, Wu T, Silva AC, Massacesi L, Jacobson S, Westmoreland S, Reich DS. The formation of inflammatory demyelinated lesions in cerebral white matter. Ann Neurol 2014; 76:594-608. [PMID: 25088017 DOI: 10.1002/ana.24242] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Revised: 07/31/2014] [Accepted: 07/31/2014] [Indexed: 01/13/2023]
Abstract
OBJECTIVE Vascular permeability and inflammatory demyelination are intimately linked in the brain, but what is their temporal relationship? We aimed to determine the radiological correlates of the earliest tissue changes accompanying demyelination in a primate model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis (EAE) in the common marmoset. METHODS By 7T magnetic resonance imaging (MRI), T1 maps, proton density, and T2-weighted images were acquired before and after EAE induction in 5 marmosets (every other week before lesions appeared, weekly thereafter). From scans before and after intravenous injection of contrast material, we measured the evolution of lesional blood-brain barrier (BBB) permeability, comparing in vivo MRI to postmortem tissue examination. RESULTS On average, BBB permeability increased 3.5-fold (p < 0.0001) over the 4 weeks prior to lesion appearance. Permeability gradually decreased after lesion appearance, with attendant changes in the distribution of inflammatory cells (predominantly macrophages and microglia) and demyelination. On tissue analysis, we also identified small perivascular foci of microglia and T cells without blood-derived macrophages or demyelination. These foci had no visible MRI correlates, although permeability within the foci, but not outside, increased in the weeks before the animals died (p < 0.0001). INTERPRETATION This study provides compelling evidence that in marmoset EAE, which forms lesions strongly resembling those of MS, early changes in vascular permeability are associated with perivascular inflammatory cuffing and parenchymal microglial activation but precede the arrival of blood-derived monocytes that accompany demyelination. Prospective detection of transient permeability changes could afford an opportunity for early intervention to forestall tissue damage in newly forming lesions.
Collapse
Affiliation(s)
- Pietro Maggi
- National Institute for Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA; Department of Neurosciences, Drug Research, and Child's Health, University of Florence, Florence, Italy
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Using high-resolution quantitative mapping of R1 as an index of cortical myelination. Neuroimage 2014; 93 Pt 2:176-88. [DOI: 10.1016/j.neuroimage.2013.06.005] [Citation(s) in RCA: 253] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 06/03/2013] [Accepted: 06/04/2013] [Indexed: 01/19/2023] Open
|
21
|
Tourdias T, Saranathan M, Levesque IR, Su J, Rutt BK. Visualization of intra-thalamic nuclei with optimized white-matter-nulled MPRAGE at 7T. Neuroimage 2013; 84:534-45. [PMID: 24018302 DOI: 10.1016/j.neuroimage.2013.08.069] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Revised: 07/27/2013] [Accepted: 08/29/2013] [Indexed: 12/01/2022] Open
Abstract
Novel MR image acquisition strategies have been investigated to elicit contrast within the thalamus, but direct visualization of individual thalamic nuclei remains a challenge because of their small size and the low intrinsic contrast between adjacent nuclei. We present a step-by-step specific optimization of the 3D MPRAGE pulse sequence at 7T to visualize the intra-thalamic nuclei. We first measured T1 values within different sub-regions of the thalamus at 7T in 5 individuals. We used these to perform simulations and sequential experimental measurements (n=17) to tune the parameters of the MPRAGE sequence. The optimal set of parameters was used to collect high-quality data in 6 additional volunteers. Delineation of thalamic nuclei was performed twice by one rater and MR-defined nuclei were compared to the classic Morel histological atlas. T1 values within the thalamus ranged from 1400ms to 1800ms for adjacent nuclei. Using these values for theoretical evaluations combined with in vivo measurements, we showed that a short inversion time (TI) close to the white matter null regime (TI=670ms) enhanced the contrast between the thalamus and the surrounding tissues, and best revealed intra-thalamic contrast. At this particular nulling regime, lengthening the time between successive inversion pulses (TS=6000ms) increased the thalamic signal and contrast and lengthening the α pulse train time (N*TR) further increased the thalamic signal. Finally, a low flip angle during the gradient echo acquisition (α=4°) was observed to mitigate the blur induced by the evolution of the magnetization along the α pulse train. This optimized set of parameters enabled the 3D delineation of 15 substructures in all 6 individuals; these substructures corresponded well with the known anatomical structures of the thalamus based on the classic Morel atlas. The mean Euclidean distance between the centers of mass of MR- and Morel atlas-defined nuclei was 2.67mm (±1.02mm). The reproducibility of the MR-defined nuclei was excellent with intraclass correlation coefficient measured at 0.997 and a mean Euclidean distance between corresponding centers of mass found at first versus second readings of 0.69mm (±0.38mm). This 7T strategy paves the way to better identification of thalamic nuclei for neurosurgical planning and investigation of regional changes in neurological disorders.
Collapse
Affiliation(s)
- Thomas Tourdias
- Richard M. Lucas Center for Imaging, Radiology Department, Stanford University, 1201 Welch Road, Stanford, CA 94305-5488, USA.
| | | | | | | | | |
Collapse
|
22
|
Bazin PL, Weiss M, Dinse J, Schäfer A, Trampel R, Turner R. A computational framework for ultra-high resolution cortical segmentation at 7Tesla. Neuroimage 2013; 93 Pt 2:201-9. [PMID: 23623972 DOI: 10.1016/j.neuroimage.2013.03.077] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Revised: 02/15/2013] [Accepted: 03/29/2013] [Indexed: 11/16/2022] Open
Abstract
This paper presents a computational framework for whole brain segmentation of 7Tesla magnetic resonance images able to handle ultra-high resolution data. The approach combines multi-object topology-preserving deformable models with shape and intensity atlases to encode prior anatomical knowledge in a computationally efficient algorithm. Experimental validation on simulated and real brain images shows accuracy and robustness of the method and demonstrates the benefits of an increased processing resolution.
Collapse
Affiliation(s)
- Pierre-Louis Bazin
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
| | - Marcel Weiss
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Juliane Dinse
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Andreas Schäfer
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Robert Trampel
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Robert Turner
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| |
Collapse
|
23
|
Helms G, Garea-Rodriguez E, Schlumbohm C, König J, Dechent P, Fuchs E, Wilke M. Structural and quantitative neuroimaging of the common marmoset monkey using a clinical MRI system. J Neurosci Methods 2013; 215:121-31. [DOI: 10.1016/j.jneumeth.2013.02.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 01/19/2013] [Accepted: 02/14/2013] [Indexed: 01/02/2023]
|
24
|
In vivo quantification of T₂ anisotropy in white matter fibers in marmoset monkeys. Neuroimage 2011; 59:979-85. [PMID: 21906687 DOI: 10.1016/j.neuroimage.2011.08.064] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Revised: 08/10/2011] [Accepted: 08/21/2011] [Indexed: 12/11/2022] Open
Abstract
T₂-weighted MRI at high field is a promising approach for studying noninvasively the tissue structure and composition of the brain. However, the biophysical origin of T₂ contrast, especially in white matter, remains poorly understood. Recent work has shown that R₂ (=1/T₂) may depend on the tissue's orientation relative to the static magnetic field (B(0)) and suggested that this dependence could be attributed to local anisotropy in the magnetic properties of brain tissue. In the present work, we analyzed high-resolution, multi-gradient-echo images of in vivo marmoset brains at 7T, and compared them with ex vivo diffusion tensor images, to show that R₂ relaxation in white matter is highly sensitive to the fiber orientation relative to the main field. We directly demonstrate this orientation dependence by performing in vivo multi-gradient-echo experiments in two orthogonal brain positions, uncovering a nearly 50% change in the R₂ relaxation rate constant of the optic radiations. We attribute this substantial R₂ anisotropy to local subvoxel susceptibility effects arising from the highly ordered and anisotropic structure of the myelin sheath.
Collapse
|