1
|
Maher S, Seed M. Fetal Cardiovascular MR Imaging. Magn Reson Imaging Clin N Am 2024; 32:479-487. [PMID: 38944435 DOI: 10.1016/j.mric.2024.04.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/01/2024]
Abstract
Prenatal diagnosis of congenital heart disease allows for appropriate planning of delivery and an opportunity to inform families about the prognosis of the cardiac malformation. On occasion, prenatal therapies may be offered to improve perinatal outcomes. While ultrasound is the primary diagnostic method, advances have led to interest in fetal MRI for its potential to aid in clinical decision-making. This review explores technical innovations and the clinical utility of fetal cardiovascular magnetic resonance (CMR), highlighting its role in diagnosing and planning interventions for complex heart conditions. Future directions include the prediction of perinatal physiology and guidance of delivery planning.
Collapse
Affiliation(s)
- Samer Maher
- Department of Physiology, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada
| | - Mike Seed
- Cardiology, The Hospital for Sick Children, University of Toronto, 170 Elizabeth Street, Toronto, Ontario, Canada.
| |
Collapse
|
2
|
Vucevic D, Malis V, Bae WC, Ota H, Oshio K, McDonald MA, Miyazaki M. Visualization of Cerebrospinal Fluid Outflow and Egress along the Nerve Roots of the Lumbar Spine. Bioengineering (Basel) 2024; 11:708. [PMID: 39061790 PMCID: PMC11273714 DOI: 10.3390/bioengineering11070708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2024] [Revised: 07/10/2024] [Accepted: 07/11/2024] [Indexed: 07/28/2024] Open
Abstract
Intrinsic cerebrospinal fluid (CSF) dynamics in the brain have been extensively studied, particularly the egress sites of tagged intrinsic CSF in the meninges. Although spinal CSF recirculates within the central nervous system (CNS), we hypothesized that CSF outflows from the lumbar spinal canal. We aimed to visualize and semi-quantify the outflow using non-contrast MRI techniques. We utilized a 3 Tesla clinical MRI with a 16-channel spine coil, employing time-spatial labeling inversion (Time-SLIP) with tag-on and tag-off acquisitions, T2-weighted coronal 2D fluid-attenuated inversion recovery (FLAIR) and T2-weighted coronal 3D centric ky-kz single-shot FSE (cSSFSE). Images were acquired using time-spatial labeling inversion pulse (Time-SLIP) with tag-on and tag-off acquisitions with varying TI periods. Ten healthy volunteers with no known spinal diseases participated. Variations in tagged CSF outflow were observed across different thoracolumbar nerve root segments in all participants. We quantified CSF outflow at all lumbar levels and the psoas region. There was no significant difference among the ROIs for signal intensity. The tagged CSF outflow from the spinal canal is small but demonstrates egress to surrounding tissues. This finding may pave the way for exploring intrathecal drug delivery, understanding of CSF-related pathologies and its potential as a biomarker for peripheral neuropathy and radiculopathy.
Collapse
Affiliation(s)
- Diana Vucevic
- Department of Radiology, University of California San Diego, La Jolla, CA 92093, USA; (D.V.); (V.M.); (W.C.B.); (M.A.M.)
| | - Vadim Malis
- Department of Radiology, University of California San Diego, La Jolla, CA 92093, USA; (D.V.); (V.M.); (W.C.B.); (M.A.M.)
| | - Won C. Bae
- Department of Radiology, University of California San Diego, La Jolla, CA 92093, USA; (D.V.); (V.M.); (W.C.B.); (M.A.M.)
- Department of Radiology, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Hideki Ota
- Department of Radiology, Tohoku University, Sendai 980-8576, Miyagi, Japan;
| | - Koichi Oshio
- Department of Radiology, Juntendo University, Tokyo 113-8421, Japan;
| | - Marin A. McDonald
- Department of Radiology, University of California San Diego, La Jolla, CA 92093, USA; (D.V.); (V.M.); (W.C.B.); (M.A.M.)
| | - Mitsue Miyazaki
- Department of Radiology, University of California San Diego, La Jolla, CA 92093, USA; (D.V.); (V.M.); (W.C.B.); (M.A.M.)
| |
Collapse
|
3
|
Ouyang M, Detre JA, Hyland JL, Sindabizera KL, Kuschner ES, Edgar JC, Peng Y, Huang H. Spatiotemporal cerebral blood flow dynamics underlies emergence of the limbic-sensorimotor-association cortical gradient in human infancy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.10.588784. [PMID: 38645183 PMCID: PMC11030426 DOI: 10.1101/2024.04.10.588784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Infant cerebral blood flow (CBF) delivers nutrients and oxygen to fulfill brain energy consumption requirements for the fastest period of postnatal brain development across lifespan. However, organizing principle of whole-brain CBF dynamics during infancy remains obscure. Leveraging a unique cohort of 100+ infants with high-resolution arterial spin labeled MRI, we found the emergence of the cortical hierarchy revealed by highest-resolution infant CBF maps available to date. Infant CBF across cortical regions increased in a biphasic pattern with initial rapid and sequentially slower rate, with break-point ages increasing along the limbic-sensorimotor-association cortical gradient. Increases in CBF in sensorimotor cortices were associated with enhanced language and motor skills, and frontoparietal association cortices for cognitive skills. The study discovered emergence of the hierarchical limbic-sensorimotor-association cortical gradient in infancy, and offers standardized reference of infant brain CBF and insight into the physiological basis of cortical specialization and real-world infant developmental functioning.
Collapse
Affiliation(s)
- Minhui Ouyang
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, Philadelphia, PA, 19104, United States
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104, United States
| | - John A Detre
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104, United States
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104, United States
| | - Jessica L Hyland
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, Philadelphia, PA, 19104, United States
| | - Kay L Sindabizera
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, Philadelphia, PA, 19104, United States
| | - Emily S Kuschner
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, Philadelphia, PA, 19104, United States
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104, United States
| | - J Christopher Edgar
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, Philadelphia, PA, 19104, United States
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104, United States
| | - Yun Peng
- Department of Radiology, Beijing Children's Hospital, Capital Medical University, Beijing, 100045, China
| | - Hao Huang
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, Philadelphia, PA, 19104, United States
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104, United States
| |
Collapse
|
4
|
Gou Y, Golden WC, Lin Z, Shepard J, Tekes A, Hu Z, Li X, Oishi K, Albert M, Lu H, Liu P, Jiang D. Automatic Rejection based on Tissue Signal (ARTS) for motion-corrected quantification of cerebral venous oxygenation in neonates and older adults. Magn Reson Imaging 2024; 105:92-99. [PMID: 37939974 PMCID: PMC10841989 DOI: 10.1016/j.mri.2023.11.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 11/04/2023] [Indexed: 11/10/2023]
Abstract
OBJECTIVE Cerebral venous oxygenation (Yv) is a key parameter for the brain's oxygen utilization and has been suggested to be a valuable biomarker in various brain diseases including hypoxic ischemic encephalopathy in neonates and Alzheimer's disease in older adults. T2-Relaxation-Under-Spin-Tagging (TRUST) MRI is a widely used technique to measure global Yv level and has been validated against gold-standard PET. However, subject motion during TRUST MRI scan can introduce considerable errors in Yv quantification, especially for noncompliant subjects. The aim of this study was to develop an Automatic Rejection based on Tissue Signal (ARTS) algorithm for automatic detection and exclusion of motion-contaminated images to improve the precision of Yv quantification. METHODS TRUST MRI data were collected from a neonatal cohort (N = 37, 16 females, gestational age = 39.12 ± 1.11 weeks, postnatal age = 1.89 ± 0.74 days) and an older adult cohort (N = 223, 134 females, age = 68.02 ± 9.01 years). Manual identification of motion-corrupted images was conducted for both cohorts to serve as a gold-standard. 9.3% of the images in the neonatal datasets and 0.4% of the images in the older adult datasets were manually identified as motion-contaminated. The ARTS algorithm was trained using the neonatal datasets. TRUST Yv values, as well as the estimation uncertainty (ΔR2) and test-retest coefficient-of-variation (CoV) of Yv, were calculated with and without ARTS motion exclusion. The ARTS algorithm was tested on datasets of older adults: first on the original adult datasets with little motion, and then on simulated adult datasets where the percentage of motion-corrupted images matched that of the neonatal datasets. RESULTS In the neonatal datasets, the ARTS algorithm exhibited a sensitivity of 0.95 and a specificity of 0.97 in detecting motion-contaminated images. Compared to no motion exclusion, ARTS significantly reduced the ΔR2 (median = 3.68 Hz vs. 4.89 Hz, P = 0.0002) and CoV (median = 2.57% vs. 6.87%, P = 0.0005) of Yv measurements. In the original older adult datasets, the sensitivity and specificity of ARTS were 0.70 and 1.00, respectively. In the simulated adult datasets, ARTS demonstrated a sensitivity of 0.91 and a specificity of 1.00. Additionally, ARTS significantly reduced the ΔR2 compared to no motion exclusion (median = 2.15 Hz vs. 3.54 Hz, P < 0.0001). CONCLUSION ARTS can improve the reliability of Yv estimation in noncompliant subjects, which may enhance the utility of Yv as a biomarker for brain diseases.
Collapse
Affiliation(s)
- Yifan Gou
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - W Christopher Golden
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Zixuan Lin
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jennifer Shepard
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Aylin Tekes
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Zhiyi Hu
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Xin Li
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Kumiko Oishi
- Center for Imaging Science, Johns Hopkins University Whiting School of Engineering, Baltimore, MD, USA
| | - Marilyn Albert
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Hanzhang Lu
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA; The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA; F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
| | - Peiying Liu
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Dengrong Jiang
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| |
Collapse
|
5
|
DeBeer T, Jordan LC, Waddle S, Lee C, Patel NJ, Garza M, Davis LT, Pruthi S, Jones S, Donahue MJ. Red cell exchange transfusions increase cerebral capillary transit times and may alter oxygen extraction in sickle cell disease. NMR IN BIOMEDICINE 2023; 36:e4889. [PMID: 36468659 PMCID: PMC10106384 DOI: 10.1002/nbm.4889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 11/30/2022] [Accepted: 12/02/2022] [Indexed: 05/17/2023]
Abstract
Persons with sickle cell disease (SCD) suffer from chronic hemolytic anemia, reduced blood oxygen content, and lifelong risk of silent and overt stroke. Major conventional stroke risk factors are absent in most individuals with SCD, yet nearly 50% have evidence of brain infarcts by the age of 30 years, indicating alternative etiologies for ischemia. We investigated whether radiological evidence of accelerated blood water transit through capillaries, visible on arterial spin labeling (ASL) magnetic resonance imaging, reduces following transfusion-induced increases in hemoglobin and relates to oxygen extraction fraction (OEF). Neurological evaluation along with anatomical and hemodynamic imaging with cerebral blood flow (CBF)-weighted pseudocontinuous ASL and OEF imaging with T2 -relaxation-under-spin-tagging were applied in sequence before and after blood transfusion therapy (n = 32) and in a comparator cohort of nontransfused SCD participants on hydroxyurea therapy scanned at two time points to assess stability without interim intervention (n = 13). OEF was calculated separately using models derived from human hemoglobin-F, hemoglobin-A, and hemoglobin-S. Gray matter CBF and dural sinus signal, indicative of rapid blood transit, were evaluated at each time point and compared with OEF using paired statistical tests (significance: two-sided p < 0.05). No significant change in sinus signal was observed in nontransfused participants (p = 0.650), but a reduction was observed in transfused participants (p = 0.034), consistent with slower red cell transit following transfusion. The dural sinus signal intensity was inversely associated with OEF pretransfusion (p = 0.011), but not posttransfusion. Study findings suggest that transfusion-induced increases in total hemoglobin may lengthen blood transit times through cerebral capillaries and alter cerebral OEF in SCD.
Collapse
Affiliation(s)
- Tonner DeBeer
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Lori C. Jordan
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Spencer Waddle
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Chelsea Lee
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Niral J. Patel
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Maria Garza
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - L. Taylor Davis
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Sumit Pruthi
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Sky Jones
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Manus J. Donahue
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| |
Collapse
|
6
|
Fortier V, Levesque IR. MR-oximetry with fat DESPOT. Magn Reson Imaging 2023; 97:112-121. [PMID: 36608912 DOI: 10.1016/j.mri.2022.12.023] [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: 09/27/2022] [Revised: 12/23/2022] [Accepted: 12/31/2022] [Indexed: 01/07/2023]
Abstract
PURPOSE The R1 relaxation rate of fat is a promising marker of tissue oxygenation. Existing techniques to map fat R1 in MR-oximetry offer limited spatial coverage, require long scan times, or pulse sequences that are not readily available on clinical scanners. This work addresses these limitations with a 3D voxel-wise fat R1 mapping technique for MR-oximetry based on a variable flip angle (VFA) approach at 3 T. METHODS Varying levels of dissolved oxygen (O2) were generated in a phantom consisting of vials of safflower oil emulsion, used to approximate human fat. Joint voxel-wise mapping of fat and water R1 was performed with a two-compartment VFA model fitted to multi-echo gradient-echo magnitude data acquired at four flip angles, referred to as Fat DESPOT. Global R1 was also calculated. Variations of fat, water, and global R1 were investigated as a function of the partial pressure of O2 (pO2). Inversion-prepared stimulated echo magnetic resonance spectroscopy was used as the reference technique for R1 measurements. RESULTS Fat R1 from Fat DESPOT was more sensitive than water R1 and global R1 to variations in pO2, consistent with previous studies performed with different R1 mapping techniques. Fat R1 sensitivity to pO2 variations with Fat DESPOT (median O2 relaxivity r1, O2 = 1.57× 10-3 s-1 mmHg-1) was comparable to spectroscopy-based measurements for methylene, the main fat resonance (median r1, O2= 1.80 × 10-3 s-1 mmHg-1). CONCLUSION Fat and water R1 can be measured on a voxel-wise basis using a two-component fit to multi-echo 3D VFA magnitude data in a clinically acceptable scan time. Fat and water R1 measured with Fat DESPOT were sensitive to variations in pO2. These observations suggest an approach to 3D in vivo MR oximetry.
Collapse
Affiliation(s)
- Véronique Fortier
- Medical Physics Unit, McGill University, Montréal, QC, Canada; Biomedical Engineering, McGill University, Montréal, QC, Canada; Medical Imaging, McGill University Health Centre, Montréal, QC, Canada; Department of Diagnostic Radiology, McGill University, Montréal, QC, Canada; Gerald Bronfman Department of Oncology, McGill University, Montréal, QC, Canada.
| | - Ives R Levesque
- Medical Physics Unit, McGill University, Montréal, QC, Canada; Biomedical Engineering, McGill University, Montréal, QC, Canada; Gerald Bronfman Department of Oncology, McGill University, Montréal, QC, Canada; Research Institute of the McGill University Health Centre, Montréal, QC, Canada
| |
Collapse
|
7
|
Roller FC, Schüßler A, Kremer N, Harth S, Kriechbaum SD, Wiedenroth CB, Guth S, Breithecker A, Richter M, Tello K, Seeger W, Mayer E, Krombach GA. Value of Right and Left Ventricular T1 and T2 Blood Pool Mapping in Patients with Chronic Thromboembolic Hypertension before and after Balloon Pulmonary Angioplasty. J Clin Med 2023; 12:jcm12062092. [PMID: 36983095 PMCID: PMC10052780 DOI: 10.3390/jcm12062092] [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: 02/04/2023] [Revised: 03/02/2023] [Accepted: 03/04/2023] [Indexed: 03/30/2023] Open
Abstract
BACKGROUND Parametric imaging has taken a steep rise in recent years and non-cardiac applications are of increasing interest. Therefore, the aim of our study was to assess right (RV) and left ventricular (LV) blood pool T1 and T2 values in patients with chronic thromboembolic pulmonary hypertension (CTEPH) compared to control subjects and their correlation to pulmonary hemodynamic. METHODS 26 patients with CTEPH (mean age 64.8 years ± 12.8 SD; 15 female), who underwent CMR and right heart catheterization (RHC) before and 6-months after balloon pulmonary angioplasty (BPA), were retrospectively included. Ventricular blood pool values were measured, compared to control subjects (mean age 40.5 years ± 12.8 SD; 16 female) and correlated to invasive measures (CI, mPAP, PVR). RESULTS In both, control subjects and CTEPH patients, RVT1 and RVT2 were significantly reduced compared to LVT1 and LVT2. Compared to control subjects, RVT2 was significantly reduced in CTEPH patients (p = 0.0065) and increased significantly after BPA (p = 0.0048). Moreover, RVT2 was positively correlated with CI and negatively correlated with mPAP and PVR before (r = 0.5155, r = -0.2541, r = -0.4571) and after BPA (r = 0.4769, r = -0.2585, r = -0.4396). CONCLUSION Ventricular blood pool T2 mapping might be novel non-invasive CMR imaging marker for assessment of disease severity, prognosis, follow-up and even therapy monitoring in PH.
Collapse
Affiliation(s)
- Fritz C Roller
- Department of Diagnostic and Interventional Radiology, Justus-Liebig-University Giessen, Klinikstraße 33, 35392 Giessen, Germany
- German Center for Lung Research (DZL), 35392 Giessen, Germany
| | - Armin Schüßler
- Department of Diagnostic and Interventional Radiology, Justus-Liebig-University Giessen, Klinikstraße 33, 35392 Giessen, Germany
- German Center for Lung Research (DZL), 35392 Giessen, Germany
| | - Nils Kremer
- German Center for Lung Research (DZL), 35392 Giessen, Germany
- Department of Internal Medicine, Universities of Giessen and Marburg Lung Center (UGMLC), Institute for Lung Health (ILH), Cardio-Pulmonary Institute (CPI), 35392 Giessen, Germany
| | - Sebastian Harth
- Department of Diagnostic and Interventional Radiology, Justus-Liebig-University Giessen, Klinikstraße 33, 35392 Giessen, Germany
- German Center for Lung Research (DZL), 35392 Giessen, Germany
| | - Steffen D Kriechbaum
- Department of Cardiology, Kerckhoff Heart and Thorax Centre, 61231 Bad Nauheim, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Rhein-Main, 60323 Frankfurt am Main, Germany
| | - Christoph B Wiedenroth
- Department of Thoracic Surgery, Kerckhoff Heart and Thorax Centre, 61231 Bad Nauheim, Germany
| | - Stefan Guth
- Department of Thoracic Surgery, Kerckhoff Heart and Thorax Centre, 61231 Bad Nauheim, Germany
| | - Andreas Breithecker
- Department of Radiology, Kerckhoff Heart and Thorax Centre, 61231 Bad Nauheim, Germany
| | - Manuel Richter
- German Center for Lung Research (DZL), 35392 Giessen, Germany
- Department of Internal Medicine, Universities of Giessen and Marburg Lung Center (UGMLC), Institute for Lung Health (ILH), Cardio-Pulmonary Institute (CPI), 35392 Giessen, Germany
| | - Khodr Tello
- German Center for Lung Research (DZL), 35392 Giessen, Germany
- Department of Internal Medicine, Universities of Giessen and Marburg Lung Center (UGMLC), Institute for Lung Health (ILH), Cardio-Pulmonary Institute (CPI), 35392 Giessen, Germany
| | - Werner Seeger
- German Center for Lung Research (DZL), 35392 Giessen, Germany
- Department of Internal Medicine, Universities of Giessen and Marburg Lung Center (UGMLC), Institute for Lung Health (ILH), Cardio-Pulmonary Institute (CPI), 35392 Giessen, Germany
| | - Eckhard Mayer
- Department of Thoracic Surgery, Kerckhoff Heart and Thorax Centre, 61231 Bad Nauheim, Germany
| | - Gabriele A Krombach
- Department of Diagnostic and Interventional Radiology, Justus-Liebig-University Giessen, Klinikstraße 33, 35392 Giessen, Germany
- German Center for Lung Research (DZL), 35392 Giessen, Germany
| |
Collapse
|
8
|
Sylvester CM, Kaplan S, Myers MJ, Gordon EM, Schwarzlose RF, Alexopoulos D, Nielsen AN, Kenley JK, Meyer D, Yu Q, Graham AM, Fair DA, Warner BB, Barch DM, Rogers CE, Luby JL, Petersen SE, Smyser CD. Network-specific selectivity of functional connections in the neonatal brain. Cereb Cortex 2023; 33:2200-2214. [PMID: 35595540 PMCID: PMC9977389 DOI: 10.1093/cercor/bhac202] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 04/28/2022] [Accepted: 04/29/2022] [Indexed: 11/13/2022] Open
Abstract
The adult human brain is organized into functional brain networks, groups of functionally connected segregated brain regions. A key feature of adult functional networks is long-range selectivity, the property that spatially distant regions from the same network have higher functional connectivity than spatially distant regions from different networks. Although it is critical to establish the status of functional networks and long-range selectivity during the neonatal period as a foundation for typical and atypical brain development, prior work in this area has been mixed. Although some studies report distributed adult-like networks, other studies suggest that neonatal networks are immature and consist primarily of spatially isolated regions. Using a large sample of neonates (n = 262), we demonstrate that neonates have long-range selective functional connections for the default mode, fronto-parietal, and dorsal attention networks. An adult-like pattern of functional brain networks is evident in neonates when network-detection algorithms are tuned to these long-range connections, when using surface-based registration (versus volume-based registration), and as per-subject data quantity increases. These results help clarify factors that have led to prior mixed results, establish that key adult-like functional network features are evident in neonates, and provide a foundation for studies of typical and atypical brain development.
Collapse
Affiliation(s)
- Chad M Sylvester
- Department of Psychiatry, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
| | - Sydney Kaplan
- Department of Neurology, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
| | - Michael J Myers
- Department of Psychiatry, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
| | - Evan M Gordon
- Department of Radiology, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
| | - Rebecca F Schwarzlose
- Department of Psychiatry, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
| | - Dimitrios Alexopoulos
- Department of Neurology, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
| | - Ashley N Nielsen
- Department of Neurology, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
| | - Jeanette K Kenley
- Department of Neurology, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
| | - Dominique Meyer
- Department of Neurology, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
| | - Qiongru Yu
- Joint Doctoral Program in Clinical Psychology, San Diego State University/University of California San Diego, 6363 Alvarado Court, Suite 103, San Diego, CA 92120, USA
| | - Alice M Graham
- Department of Psychiatry, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - Damien A Fair
- Masonic Institute for the Developing Brain, Department of Pediatrics, and Institute of Child Development, University of Minnesota, 2025 E. River Parkway, Minneapolis, MN 55414, USA
| | - Barbara B Warner
- Department of Pediatrics, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
| | - Deanna M Barch
- Department of Psychiatry, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
- Department of Radiology, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
- Department of Psychological and Brain Sciences, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
| | - Cynthia E Rogers
- Department of Psychiatry, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
- Department of Pediatrics, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
| | - Joan L Luby
- Department of Psychiatry, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
| | - Steven E Petersen
- Department of Neurology, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
| | - Christopher D Smyser
- Department of Neurology, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
- Department of Radiology, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
- Department of Pediatrics, Washington University, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
| |
Collapse
|
9
|
Yu Q, Ouyang M, Detre J, Kang H, Hu D, Hong B, Fang F, Peng Y, Huang H. Infant brain regional cerebral blood flow increases supporting emergence of the default-mode network. eLife 2023; 12:e78397. [PMID: 36693116 PMCID: PMC9873253 DOI: 10.7554/elife.78397] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Accepted: 01/12/2023] [Indexed: 01/25/2023] Open
Abstract
Human infancy is characterized by most rapid regional cerebral blood flow (rCBF) increases across lifespan and emergence of a fundamental brain system default-mode network (DMN). However, how infant rCBF changes spatiotemporally across the brain and how the rCBF increase supports emergence of functional networks such as DMN remains unknown. Here, by acquiring cutting-edge multi-modal MRI including pseudo-continuous arterial-spin-labeled perfusion MRI and resting-state functional MRI of 48 infants cross-sectionally, we elucidated unprecedented 4D spatiotemporal infant rCBF framework and region-specific physiology-function coupling across infancy. We found that faster rCBF increases in the DMN than visual and sensorimotor networks. We also found strongly coupled increases of rCBF and network strength specifically in the DMN, suggesting faster local blood flow increase to meet extraneuronal metabolic demands in the DMN maturation. These results offer insights into the physiological mechanism of brain functional network emergence and have important implications in altered network maturation in brain disorders.
Collapse
Affiliation(s)
- Qinlin Yu
- Department of Radiology, Children’s Hospital of PhiladelphiaPhiladelphiaUnited States
- Department of Radiology, Perelman School of Medicine, University of PennsylvaniaPhiladelphiaUnited States
| | - Minhui Ouyang
- Department of Radiology, Children’s Hospital of PhiladelphiaPhiladelphiaUnited States
- Department of Radiology, Perelman School of Medicine, University of PennsylvaniaPhiladelphiaUnited States
| | - John Detre
- Department of Radiology, Perelman School of Medicine, University of PennsylvaniaPhiladelphiaUnited States
- Department of Neurology, Perelman School of Medicine, University of PennsylvaniaPhiladelphiaUnited States
| | - Huiying Kang
- Department of Radiology, Children’s Hospital of PhiladelphiaPhiladelphiaUnited States
- Department of Radiology, Beijing Children’s Hospital, Capital Medical UniversityBeijingChina
| | - Di Hu
- Department of Radiology, Children’s Hospital of PhiladelphiaPhiladelphiaUnited States
- Department of Radiology, Beijing Children’s Hospital, Capital Medical UniversityBeijingChina
| | - Bo Hong
- Department of Biomedical Engineering, Tsinghua UniversityBeijingChina
| | - Fang Fang
- School of Psychological and Cognitive Sciences, Peking UniversityBeijingChina
| | - Yun Peng
- Department of Radiology, Beijing Children’s Hospital, Capital Medical UniversityBeijingChina
| | - Hao Huang
- Department of Radiology, Children’s Hospital of PhiladelphiaPhiladelphiaUnited States
- Department of Radiology, Perelman School of Medicine, University of PennsylvaniaPhiladelphiaUnited States
| |
Collapse
|
10
|
Chen JJ, Uthayakumar B, Hyder F. Mapping oxidative metabolism in the human brain with calibrated fMRI in health and disease. J Cereb Blood Flow Metab 2022; 42:1139-1162. [PMID: 35296177 PMCID: PMC9207484 DOI: 10.1177/0271678x221077338] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Conventional functional MRI (fMRI) with blood-oxygenation level dependent (BOLD) contrast is an important tool for mapping human brain activity non-invasively. Recent interest in quantitative fMRI has renewed the importance of oxidative neuroenergetics as reflected by cerebral metabolic rate of oxygen consumption (CMRO2) to support brain function. Dynamic CMRO2 mapping by calibrated fMRI require multi-modal measurements of BOLD signal along with cerebral blood flow (CBF) and/or volume (CBV). In human subjects this "calibration" is typically performed using a gas mixture containing small amounts of carbon dioxide and/or oxygen-enriched medical air, which are thought to produce changes in CBF (and CBV) and BOLD signal with minimal or no CMRO2 changes. However non-human studies have demonstrated that the "calibration" can also be achieved without gases, revealing good agreement between CMRO2 changes and underlying neuronal activity (e.g., multi-unit activity and local field potential). Given the simpler set-up of gas-free calibrated fMRI, there is evidence of recent clinical applications for this less intrusive direction. This up-to-date review emphasizes technological advances for such translational gas-free calibrated fMRI experiments, also covering historical progression of the calibrated fMRI field that is impacting neurological and neurodegenerative investigations of the human brain.
Collapse
Affiliation(s)
- J Jean Chen
- Medical Biophysics, University of Toronto, Toronto, Canada.,Rotman Research Institute, Baycrest, Toronto, Canada
| | - Biranavan Uthayakumar
- Medical Biophysics, University of Toronto, Toronto, Canada.,Sunnybrook Research Institute, Toronto, Canada
| | - Fahmeed Hyder
- Magnetic Resonance Research Center (MRRC), Yale University, New Haven, Connecticut, USA.,Department of Radiology, Yale University, New Haven, Connecticut, USA.,Quantitative Neuroscience with Magnetic Resonance (QNMR) Research Program, Yale University, New Haven, Connecticut, USA.,Department of Biomedical Engineering, Yale University, New Haven, Connecticut, USA
| |
Collapse
|
11
|
Jiang D, Lu H. Cerebral oxygen extraction fraction MRI: Techniques and applications. Magn Reson Med 2022; 88:575-600. [PMID: 35510696 PMCID: PMC9233013 DOI: 10.1002/mrm.29272] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 03/20/2022] [Accepted: 03/29/2022] [Indexed: 12/20/2022]
Abstract
The human brain constitutes 2% of the body's total mass but uses 20% of the oxygen. The rate of the brain's oxygen utilization can be derived from a knowledge of cerebral blood flow and the oxygen extraction fraction (OEF). Therefore, OEF is a key physiological parameter of the brain's function and metabolism. OEF has been suggested to be a useful biomarker in a number of brain diseases. With recent advances in MRI techniques, several MRI-based methods have been developed to measure OEF in the human brain. These MRI OEF techniques are based on the T2 of blood, the blood signal phase, the magnetic susceptibility of blood-containing voxels, the effect of deoxyhemoglobin on signal behavior in extravascular tissue, and the calibration of the BOLD signal using gas inhalation. Compared to 15 O PET, which is considered the "gold standard" for OEF measurement, MRI-based techniques are non-invasive, radiation-free, and are more widely available. This article provides a review of these emerging MRI-based OEF techniques. We first briefly introduce the role of OEF in brain oxygen homeostasis. We then review the methodological aspects of different categories of MRI OEF techniques, including their signal mechanisms, acquisition methods, and data analyses. The strengths and limitations of the techniques are discussed. Finally, we review key applications of these techniques in physiological and pathological conditions.
Collapse
Affiliation(s)
- Dengrong Jiang
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Hanzhang Lu
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, Maryland, USA
| |
Collapse
|
12
|
Investigation of 1H nuclear magnetic resonance relaxometry to screen metabolic syndrome and diabetes. ANAL SCI 2022; 38:899-905. [PMID: 35438426 DOI: 10.1007/s44211-022-00113-7] [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: 11/26/2021] [Accepted: 03/23/2022] [Indexed: 11/01/2022]
Abstract
The purpose of this study was to investigate and compare the abilities of 1H nuclear magnetic resonance (NMR) transverse relaxation constant time (T2) and longitudinal relaxation constant time (T1) to screen people at the risk of diabetes and metabolic syndrome. Human blood samples were collected for NMR detection and biochemical examinations. Bivariate correlations, categorical analyses were performed to explore the relationship between NMR relaxation time and metabolic biomarkers. Results show that NMR relaxation time of human serum correlated well with some biomarkers associated with diabetes and metabolic syndrome. Statistically significant differences in NMR relaxation time between subjects with normal and poor metabolic health were observed. NMR relaxation time, especially T2, can be used to screen people at risk of diabetes and metabolic syndrome.
Collapse
|
13
|
Qi Y, Lin Z, Lu H, Zhao P, Hou Y, Mao J. The Association Between Pregnancy-Induced Hypertension and Neonatal Cerebral Metabolism, Hemodynamics, and Brain Injury as Determined by Physiological Imaging. Front Physiol 2022; 13:756386. [PMID: 35295587 PMCID: PMC8918661 DOI: 10.3389/fphys.2022.756386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Accepted: 01/24/2022] [Indexed: 11/20/2022] Open
Abstract
Pregnancy-induced hypertension (PIH) is common and may affect maternal and children’s healthcare. However, the neurobiological status of neonates born from mothers with PIH has yet to be elucidated. The present study employed physiological imaging to investigate the association between maternal PIH and a number of neonatal health parameters, including cerebral metabolism, hemodynamics, and pathophysiological vulnerabilities. Following the acquisition of ethical approval, we recruited 16 neonates with maternal PIH and 22 normal neonates (non-PIH) as controls. All neonates underwent magnetic resonance imaging (MRI) of the brain. Phase-contrast (PC) MRI and T2-relaxation-under-spin-tagging (TRUST) MRI were performed to determine global cerebral blood flow, oxygen extraction fraction (OEF), and cerebral metabolic rate of oxygen (CMRO2). These physiological parameters were then compared between PIH neonates and controls. Linear regression analysis was performed to investigate the associations between maternal PIH and each of the physiological parameters. Receiver operating characteristic curves (ROCs) were used to determine whether maternal systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) which could facilitate the diagnosis of neonatal brain injuries. PIH neonates showed significantly lower OEF (25.5 ± 8.8% vs. 32.6 ± 7.3%, P = 0.01) and CMRO2 (29.7 ± 9.4 vs. 40.9 ± 15.0 μmol/100 g/min, P = 0.01) compared to the controls. Maternal blood pressure levels [PIH or non-PIH groups, each one standard deviation (SD) increase in SBP, DBP, and MAP, respectively] were negatively associated with OEF [regression coefficient (β) = −7.9, P = 0.007; β = −4.2, P = 0.004; β = −3.6, P = 0.02; β = −4.0, P = 0.008, respectively). Furthermore, each one SD increase in maternal DBP and MAP was negatively associated with CMRO2 (β = −4.7, P = 0.03; β = −4.4, P = 0.04, respectively). The areas under the curves (AUCs) with 95% confidence intervals (CIs) for maternal SBP, DBP, and MAP were 0.90 (0.80–0.97), 0.85 (0.73–0.97), and 0.89 (0.76–0.99), respectively. The AUC values for maternal SBP, DBP, and MAP indicated good diagnostic ability for identifying neonatal brain injuries. The present study demonstrated that maternal PIH may be associated with a lower oxygen extraction and lower cerebral metabolism in neonates.
Collapse
Affiliation(s)
- Ying Qi
- Department of Radiology, Shengjing Hospital of China Medical University, Shenyang, China
- *Correspondence: Ying Qi,
| | - Zixuan Lin
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Hanzhang Lu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Pengfei Zhao
- Department of Pharmacology, School of Pharmaceutical Sciences, China Medical University, Shenyang, China
| | - Yang Hou
- Department of Radiology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Jian Mao
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang, China
| |
Collapse
|
14
|
Lin Z, McIntyre T, Jiang D, Cannon A, Liu P, Tekes A, Casella JF, Slifer K, Lu H, Lance E. Brain Oxygen Extraction and Metabolism in Pediatric Patients With Sickle Cell Disease: Comparison of Four Calibration Models. Front Physiol 2022; 13:814979. [PMID: 35222083 PMCID: PMC8874251 DOI: 10.3389/fphys.2022.814979] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Accepted: 01/21/2022] [Indexed: 12/11/2022] Open
Abstract
Sickle cell disease (SCD) is an inherited hemoglobinopathy with an increased risk of neurological complications. Due to anemia and other factors related to the underlying hemoglobinopathy, cerebral blood flow (CBF) increases as compensation; however, the nature of alterations in oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen (CMRO2) in SCD remains controversial, largely attributed to the different calibration models. In addition, limited studies have been done to investigate oxygen metabolism in pediatric patients. Thus, this study used a non-invasive T2-based MR oximetry, T2-Relaxation-Under-Spin-Tagging (TRUST) MRI, to measure oxygen homeostasis in pediatric patients with SCD using four different calibration models and examined its relationship to hematological measures. It was found that, compared with controls, SCD patients showed an increased CBF, unchanged total oxygen delivery and increased venous blood T2. The results of OEF and CMRO2 were dependent on the calibration models used. When using sickle-specific, hemoglobin S (HbS) level-dependent calibration, there was a decreased OEF and CMRO2, while the bovine model showed an opposite result. OEF and CMRO2 were also associated with hemoglobin and HbS level; the direction of the relationship was again dependent on the model. Future studies with in vivo calibration are needed to provide more accurate information on the T2-Yv relationship.
Collapse
Affiliation(s)
- Zixuan Lin
- The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Tiffany McIntyre
- Department of Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, MD, United States
| | - Dengrong Jiang
- The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Alicia Cannon
- Department of Neuropsychology, Kennedy Krieger Institute, Baltimore, MD, United States
| | - Peiying Liu
- The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Aylin Tekes
- The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - James F. Casella
- Division of Pediatric Hematology, Department of Pediatrics, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Keith Slifer
- Department of Behavioral Psychology, Kennedy Krieger Institute, Baltimore, MD, United States
- Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Hanzhang Lu
- The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, United States
| | - Eboni Lance
- Department of Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, MD, United States
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
- *Correspondence: Eboni Lance,
| |
Collapse
|
15
|
Baas KPA, Coolen BF, Petersen ET, Biemond BJ, Strijkers GJ, Nederveen AJ. Comparative Analysis of Blood T 2 Values Measured by T 2 -TRIR and TRUST. J Magn Reson Imaging 2022; 56:516-526. [PMID: 35077595 DOI: 10.1002/jmri.28066] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 12/24/2021] [Accepted: 12/28/2021] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Venous blood oxygenation (Yv), which can be derived from venous blood T2 (T2 b), combined with oxygen-extraction fraction (OEF) and cerebral metabolic rate of oxygen, is considered indicative for tissue viability and brain functioning and frequently assessed in patients with sickle cell disease. Recently, T2 -Prepared-Blood-Relaxation-Imaging-with-Inversion-Recovery (T2 -TRIR) was introduced allowing for simultaneous measurements of blood T2 and T1 (T1 b), potentially improving Yv estimation by overcoming the need to estimate hematocrit. PURPOSE To optimize and compare T2 -TRIR with T2 -relaxation-under-spin-tagging (TRUST) sequence. STUDY TYPE Prospective. POPULATION A total of 12 healthy volunteers (six female, 27 ± 3 years old) and 7 patients with sickle cell disease (five female, 32 ± 12 years old). FIELD STRENGTH/SEQUENCE 3 T; turbo field echo planar imaging (TFEPI), echo planar imaging (EPI), and fast field echo (FFE). ASSESSMENT T2 b, Yv, and OEF from TRUST and T2 -TRIR were compared and T2 -TRIR-derived T1 b was assessed. Within- and between-session repeatability was quantified in the controls, whereas sensitivity to hemodynamic changes after acetazolamide (ACZ) administration was assessed in the patients. STATISTICAL TESTS Shapiro-Wilk, one-sample and paired-sample t-test, repeated measures ANOVA, mixed linear model, Bland-Altman analysis and correlation analysis. Sidak multiple-comparison correction was performed. Significance level was 0.05. RESULTS In controls, T2 b from T2 -TRIR (70 ± 11 msec) was higher compared to TRUST (60 ± 8 msec). In patients, T2 b values were lower pre- compared to post-ACZ administration (TRUST: 80 ± 15 msec and 106 ± 23 msec and T2 -TRIR: 95 ± 21 msec and 125 ± 36 msec). Consequently, Yv and OEF were lower and higher pre- compared to post-ACZ administration (TRUST Yv: 68% ± 7% and 77% ± 8%, T2 -TRIR Yv: 74% ± 8% and 80% ± 6%, TRUST OEF: 30% ± 7% and 21% ± 8%, and T2 -TRIR OEF: 25% ± 8% and 18% ± 6%). DATA CONCLUSION TRUST and T2 -TRIR are reproducible, but T2 -TRIR-derived T2 b values are significantly higher compared to TRUST, resulting in higher Yv and lower OEF estimates. This bias might be considered when evaluating cerebral oxygen homeostasis. EVIDENCE LEVEL 2 TECHNICAL EFFICACY: Stage 2.
Collapse
Affiliation(s)
- Koen P A Baas
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, Amsterdam Cardiovascular Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Bram F Coolen
- Department of Biomedical Engineering and Physics, Amsterdam University Medical Centers, Amsterdam Cardiovascular Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Esben T Petersen
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Amager and Hvidovre, Copenhagen, Denmark.,Department of Health Technology, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Bart J Biemond
- Department of Hematology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Gustav J Strijkers
- Department of Biomedical Engineering and Physics, Amsterdam University Medical Centers, Amsterdam Cardiovascular Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Aart J Nederveen
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, Amsterdam Cardiovascular Sciences, University of Amsterdam, Amsterdam, The Netherlands
| |
Collapse
|
16
|
Wang DJJ, Le Bihan D, Krishnamurthy R, Smith M, Ho ML. Noncontrast Pediatric Brain Perfusion: Arterial Spin Labeling and Intravoxel Incoherent Motion. Magn Reson Imaging Clin N Am 2021; 29:493-513. [PMID: 34717841 DOI: 10.1016/j.mric.2021.06.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Noncontrast magnetic resonance imaging techniques for measuring brain perfusion include arterial spin labeling (ASL) and intravoxel incoherent motion (IVIM). These techniques provide noninvasive and repeatable assessment of cerebral blood flow or cerebral blood volume without the need for intravenous contrast. This article discusses the technical aspects of ASL and IVIM with a focus on normal physiologic variations, technical parameters, and artifacts. Multiple pediatric clinical applications are presented, including tumors, stroke, vasculopathy, vascular malformations, epilepsy, migraine, trauma, and inflammation.
Collapse
Affiliation(s)
- Danny J J Wang
- USC Institute for Neuroimaging and Informatics, SHN, 2025 Zonal Avenue, Health Sciences Campus, Los Angeles, CA 90033, USA
| | - Denis Le Bihan
- NeuroSpin, Centre d'études de Saclay, Bâtiment 145, Gif-sur-Yvette 91191, France
| | - Ram Krishnamurthy
- Department of Radiology, Nationwide Children's Hospital, 700 Children's Drive - ED4, Columbus, OH 43205, USA
| | - Mark Smith
- Department of Radiology, Nationwide Children's Hospital, 700 Children's Drive - ED4, Columbus, OH 43205, USA
| | - Mai-Lan Ho
- Department of Radiology, Nationwide Children's Hospital, 700 Children's Drive - ED4, Columbus, OH 43205, USA.
| |
Collapse
|
17
|
Stout JN, Liao C, Gagoski B, Turk EA, Feldman HA, Bibbo C, Barth WH, Shainker SA, Wald LL, Grant PE, Adalsteinsson E. Quantitative T 1 and T 2 mapping by magnetic resonance fingerprinting (MRF) of the placenta before and after maternal hyperoxia. Placenta 2021; 114:124-132. [PMID: 34537569 DOI: 10.1016/j.placenta.2021.08.058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 06/16/2021] [Accepted: 08/05/2021] [Indexed: 11/13/2022]
Abstract
INTRODUCTION MR relaxometry has been used to assess placental exchange function, but methods to date are not sufficiently fast to be robust to placental motion. Magnetic resonance fingerprinting (MRF) permits rapid, voxel-wise, intrinsically co-registered T1 and T2 mapping. After characterizing measurement error, we scanned pregnant women during air and oxygen breathing to demonstrate MRF's ability to detect placental oxygenation changes. METHODS The accuracy of FISP-based, sliding-window reconstructed MRF was tested on phantoms. MRF scans in 9-s breath holds were acquired at 3T in 31 pregnant women during air and oxygen breathing. A mixed effects model was used to test for changes in placenta relaxation times between physiological states, to assess the dependency on gestational age (GA), and the impact of placental motion. RESULTS MRF estimates of known phantom relaxation times resulted in mean absolute errors for T1 of 92 ms (4.8%), but T2 was less accurate at 16 ms (13.6%). During normoxia, placental T1 = 1825 ± 141 ms (avg ± standard deviation) and T2 = 60 ± 16 ms (gestational age range 24.3-36.7, median 32.6 weeks). In the statistical model, placental T2 rose and T1 remained contant after hyperoxia, and no GA dependency was observed for T1 or T2. DISCUSSION Well-characterized, motion-robust MRF was used to acquire T1 and T2 maps of the placenta. Changes with hyperoxia are consistent with a net increase in oxygen saturation. Toward the goal of whole-placenta quantitative oxygenation imaging over time, we aim to implement 3D MRF with integrated motion correction to improve T2 accuracy.
Collapse
Affiliation(s)
- Jeffrey N Stout
- Fetal and Neonatal Neuroimaging and Developmental Science Center, Boston Children's Hospital, Boston, MA, 02115, USA.
| | - Congyu Liao
- Department of Radiology, Stanford University, Stanford, CA, 94305, USA
| | - Borjan Gagoski
- Fetal and Neonatal Neuroimaging and Developmental Science Center, Boston Children's Hospital, Boston, MA, 02115, USA
| | - Esra Abaci Turk
- Fetal and Neonatal Neuroimaging and Developmental Science Center, Boston Children's Hospital, Boston, MA, 02115, USA
| | - Henry A Feldman
- Centers for Clinical and Translational Research, Boston Children's Hospital, Boston, MA, 02115, USA
| | - Carolina Bibbo
- Brigham and Women's Hospital, Division of Maternal-Fetal Medicine, Boston, MA, 02115, USA
| | - William H Barth
- Maternal-Fetal Medicine, Obstetrics and Gynecology, Massachusetts General Hospital, Boston, MA, 02114, USA
| | - Scott A Shainker
- Maternal-Fetal Medicine, Obstetrics and Gynecology, Beth Israel Deaconess Medical Center, Boston, MA, 02115, USA
| | - Lawrence L Wald
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, 02129, USA
| | - P Ellen Grant
- Fetal and Neonatal Neuroimaging and Developmental Science Center, Boston Children's Hospital, Boston, MA, 02115, USA
| | - Elfar Adalsteinsson
- Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA; Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| |
Collapse
|
18
|
Jiang D, Koehler RC, Liu X, Kulikowicz E, Lee JK, Lu H, Liu P. Quantitative validation of MRI mapping of cerebral venous oxygenation with direct blood sampling: A graded-O 2 study in piglets. Magn Reson Med 2021; 86:1445-1453. [PMID: 33755253 PMCID: PMC8184598 DOI: 10.1002/mrm.28786] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 02/12/2021] [Accepted: 03/08/2021] [Indexed: 12/21/2022]
Abstract
PURPOSE To validate two neonatal cerebral venous oxygenation (Yv ) MRI techniques, T2 relaxation under phase contrast (TRUPC) and accelerated TRUPC (aTRUPC) MRI, with oxygenation measured with direct blood sampling. METHODS In vivo experiments were performed on seven healthy newborn piglets. For each piglet, a catheter was placed in the superior sagittal sinus to obtain venous blood samples for blood gas oximetry measurement as a gold standard. During the MRI experiment, three to five venous oxygenation levels were achieved in each piglet by varying inhaled O2 content and breathing rate. Under each condition, Yv values of the superior sagittal sinus measured by TRUPC, aTRUPC, and blood gas oximetry were obtained. The Yv quantification in TRUPC and aTRUPC used a standard bovine blood calibration model. The aTRUPC scan was repeated twice to assess its reproducibility. Agreements among TRUPC Yv , aTRUPC Yv , and blood gas oximetry were evaluated by intraclass correlation coefficient (ICC) and paired Student's t-test. RESULTS The mean hematocrit was 23.6 ± 6.5% among the piglets. Across all measurements, Yv values were 51.9 ± 21.3%, 54.1 ± 18.8%, and 53.7 ± 19.2% for blood gas oximetry, TRUPC and aTRUPC, respectively, showing no significant difference between any two methods (P > .3). There were good correlations between TRUPC and blood gas Yv (ICC = 0.801; P < .0001), between aTRUPC and blood gas Yv (ICC = 0.809; P < .0001), and between aTRUPC and TRUPC Yv (ICC = 0.887; P < .0001). The coefficient of variation of aTRUPC Yv was 8.1 ± 9.9%. CONCLUSION The values of Yv measured by TRUPC and aTRUPC were in good agreement with blood gas oximetry. These findings suggest that TRUPC and aTRUPC can provide accurate quantifications of Yv in major cerebral veins.
Collapse
Affiliation(s)
- Dengrong Jiang
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Raymond C. Koehler
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Xiuyun Liu
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Ewa Kulikowicz
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jennifer K. Lee
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Hanzhang Lu
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, Maryland, USA
| | - Peiying Liu
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| |
Collapse
|
19
|
Qi Y, Wang X, Mao J. Quantitative assessment of cerebral metabolism and hemodynamics in small-for-gestational-age (SGA) newborns. Quant Imaging Med Surg 2021; 11:2321-2332. [PMID: 34079704 DOI: 10.21037/qims-20-1040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Background Small-for-gestational-age (SGA) newborns represent approximately 10% of births worldwide and 45% of births in some countries. It has been suggested that SGA might cause learning difficulties and behavioral abnormalities in childhood, yet the neurobiological basis for this is poorly understood. In this study, we employed several advanced imaging techniques-including T2-relaxation-under-spin-tagging (TRUST) magnetic resonance imaging (MRI), and phase-contrast (PC) MRI-to quantify oxygen extraction fraction (OEF), global cerebral blood flow (CBF), and cerebral metabolic rate of oxygen (CMRO2) to elucidate pathophysiological vulnerabilities of SGA neonates. Methods A total of 41 newborns were enrolled in this study, consisting of 29 SGA and 12 appropriate-for-gestational-age (AGA) neonates. The SGA group was further divided into subgroups with and without abnormalities on structural MRI, denoted as SGA-a (N=17) and SGA-n (N=12). TRUST and PC MRI were performed to determine OEF, CBF, and CMRO2. Linear regression analyses were performed to examine physiological parameters' dependence on scan age, gender, and group. Similar analyses were conducted for birth weight and brain volume. Receiver operating characteristic (ROC) curves were used to test physiological parameters' ability to different diagnostic groups. Results Regression analysis revealed that CMRO2 was significantly lower (P=0.04) in the SGA group relative to the AGA group. When further stratifying the SGA participants into SGA-a and SGA-n subgroups, the SGA-a subgroup was found to have the most pronounced physiological deficits, with a lower CMRO2 (P=0.004) and lower CBF (P=0.007) than those in the AGA group. Conversely, CMRO2 (P=0.40) and CBF (P=0.90) in the SGA-n subgroup were not different from those of the AGA group. Accordingly, CBF in the SGA-a group was significantly lower (P=0.01) than that of the SGA-n group and CMRO2 also showed a difference (P=0.09). Additionally, CMRO2 (P=0.002) and CBF (P=0.04) showed an age-related increase during this early developmental period. In analyzing the SGA-a subgroup relative to the remaining neonates, the area under curve (AUC) values were 0.6, 0.6, 0.7, 0.8, and 0.5 for birth weight, OEF, CMRO2, CBF, and brain volume, respectively. In analyzing the SGA-a subgroup relative to the SGA-n subgroup, AUC values were 0.5, 0.6, 0.7, 0.8, and 0.5 for birth weight, OEF, CMRO2, CBF, and brain volume. Conclusions Structural damage in SGA-a neonates is associated with cerebral hemodynamic and metabolic deficits. SGA neonates with normal CBF and CMRO2reveal minimal structural abnormalities. Physiological imaging may help identify SGA patients at high risk of developing irreversible brain damage.
Collapse
Affiliation(s)
- Ying Qi
- Department of Radiology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Xiaoming Wang
- Department of Radiology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Jian Mao
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang, China
| |
Collapse
|
20
|
Ali F, Bydder M, Han H, Wang D, Ghodrati V, Gao C, Prosper A, Nguyen KL, Finn JP, Hu P. Slice encoding for the reduction of outflow signal artifacts in cine balanced SSFP imaging. Magn Reson Med 2021; 86:2034-2048. [PMID: 34056755 PMCID: PMC10185493 DOI: 10.1002/mrm.28858] [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: 10/16/2020] [Revised: 05/04/2021] [Accepted: 05/06/2021] [Indexed: 11/05/2022]
Abstract
PURPOSE Standard balanced SSFP (bSSFP) cine MRI often suffers from blood outflow artifacts. We propose a method that spatially encodes these outflowing spins to reduce their effects in the intended slice. METHODS Bloch simulations were performed to characterize through-plane flow and to investigate how the use of phase encoding along the slice select's direction ("slice encoding") could alleviate its issues. Phantom scans and in vivo cines were acquired on a 3T system, comparing the standard 2D acquisition to the proposed slice-encoding method. Nineteen healthy volunteers were recruited for short-axis and horizontal long-axis oriented scans. An expert radiologist evaluated each slice-encoded/standard cine pairs in a rank comparison test and graded their quality on a 1-5 scale. The grades were used for a nonparametric paired evaluation for independent samples with a null hypothesis that there was no statistical difference between the two quality-grade distributions for α = 0.05 significance. RESULTS Bloch simulation results demonstrated this technique's feasibility, showing a fully resolved slice profile given a sufficient number of slice encodes. These results were confirmed with the phantom experiments. Each in vivo slice-encoded cine had a higher quality than its corresponding standard acquisition. The nonparametric paired evaluation came to 0.01 significance, encouraging us to reject the null hypothesis and conclude that slice-encoding effectively works in reducing outflow effects. CONCLUSION The slice-encoding balanced SSFP technique is helpful in mitigating outflow effects and is achievable within a single breath hold, being a useful alternative for cases in which the flow artifacts are significant.
Collapse
Affiliation(s)
- Fadil Ali
- Department of Radiological Sciences, University of California Los Angeles, Los Angeles, California, USA.,Physics and Biology in Medicine Inter-Departmental Graduate Program, University of California Los Angeles, Los Angeles, California, USA
| | - Mark Bydder
- Department of Radiological Sciences, University of California Los Angeles, Los Angeles, California, USA
| | - Hui Han
- Biomedical Imaging Research Center, Cedars Sinai Medical Center, Los Angeles, California, USA
| | - Da Wang
- Department of Radiation and Cellular Oncology, University of Chicago, Chicago, Illinois, USA
| | - Vahid Ghodrati
- Department of Radiological Sciences, University of California Los Angeles, Los Angeles, California, USA.,Physics and Biology in Medicine Inter-Departmental Graduate Program, University of California Los Angeles, Los Angeles, California, USA
| | - Chang Gao
- Department of Radiological Sciences, University of California Los Angeles, Los Angeles, California, USA.,Physics and Biology in Medicine Inter-Departmental Graduate Program, University of California Los Angeles, Los Angeles, California, USA
| | - Ashley Prosper
- Department of Radiological Sciences, University of California Los Angeles, Los Angeles, California, USA
| | - Kim-Lien Nguyen
- Department of Radiological Sciences, University of California Los Angeles, Los Angeles, California, USA.,Physics and Biology in Medicine Inter-Departmental Graduate Program, University of California Los Angeles, Los Angeles, California, USA.,Division of Cardiology, David Geffen School of Medicine, University of California, Los Angeles, California, USA.,Division of Cardiology, VA Greater Los Angeles Healthcare System, Los Angeles, California, USA
| | - J Paul Finn
- Department of Radiological Sciences, University of California Los Angeles, Los Angeles, California, USA
| | - Peng Hu
- Department of Radiological Sciences, University of California Los Angeles, Los Angeles, California, USA.,Physics and Biology in Medicine Inter-Departmental Graduate Program, University of California Los Angeles, Los Angeles, California, USA
| |
Collapse
|
21
|
Prussien KV, Compas BE, Siciliano RE, Ciriegio AE, Lee CA, Kassim AA, DeBaun MR, Donahue MJ, Jordan LC. Cerebral Hemodynamics and Executive Function in Sickle Cell Anemia. Stroke 2021; 52:1830-1834. [PMID: 33840223 DOI: 10.1161/strokeaha.120.032741] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Individuals with sickle cell anemia experience cognitive deficits, even in the absence of cerebral infarcts or strokes. This study tested the hypothesis that elevated cerebral blood flow and oxygen extraction fraction are associated with lower executive function in individuals with sickle cell anemia. METHODS Three-Tesla brain magnetic resonance imaging was performed, including anatomic, gray matter cerebral blood flow, and global oxygen extraction fraction imaging. Executive function was measured using the working memory index from an age-appropriate Wechsler battery and tasks from the National Institutes of Health Toolbox Cognition Battery. Bivariate and multivariate models were examined (significance: P<0.05). RESULTS Fifty-four participants (age range=6-31 years) with sickle cell anemia were enrolled. Hematocrit was positively related to fluid cognition, cerebral blood flow was inversely related to working memory and inhibitory control, and oxygen extraction fraction was inversely related to processing speed. Associations remained significant in multivariate analyses controlling for age, income, and infarcts. CONCLUSIONS Elevated cerebral blood flow and oxygen extraction fraction, markers of hemodynamic impairment, are associated with deficits in executive function in individuals with sickle cell anemia.
Collapse
Affiliation(s)
- Kemar V Prussien
- Department of Psychology and Human Development, Vanderbilt University, Nashville, TN (K.V.P., B.E.C., R.E.S., A.E.C.).,Department of Pediatrics (C.A.L., L.C.J., M.R.D.), Vanderbilt University Medical Center, Nashville, TN.,Department of Internal Medicine (A.A.K.), Vanderbilt University Medical Center, Nashville, TN.,Department of Radiology and Radiological Sciences (M.J.D.), Vanderbilt University Medical Center, Nashville, TN
| | - Bruce E Compas
- Department of Psychology and Human Development, Vanderbilt University, Nashville, TN (K.V.P., B.E.C., R.E.S., A.E.C.).,Department of Pediatrics (C.A.L., L.C.J., M.R.D.), Vanderbilt University Medical Center, Nashville, TN.,Department of Internal Medicine (A.A.K.), Vanderbilt University Medical Center, Nashville, TN.,Department of Radiology and Radiological Sciences (M.J.D.), Vanderbilt University Medical Center, Nashville, TN
| | - Rachel E Siciliano
- Department of Psychology and Human Development, Vanderbilt University, Nashville, TN (K.V.P., B.E.C., R.E.S., A.E.C.).,Department of Pediatrics (C.A.L., L.C.J., M.R.D.), Vanderbilt University Medical Center, Nashville, TN.,Department of Internal Medicine (A.A.K.), Vanderbilt University Medical Center, Nashville, TN.,Department of Radiology and Radiological Sciences (M.J.D.), Vanderbilt University Medical Center, Nashville, TN
| | - Abagail E Ciriegio
- Department of Psychology and Human Development, Vanderbilt University, Nashville, TN (K.V.P., B.E.C., R.E.S., A.E.C.).,Department of Pediatrics (C.A.L., L.C.J., M.R.D.), Vanderbilt University Medical Center, Nashville, TN.,Department of Internal Medicine (A.A.K.), Vanderbilt University Medical Center, Nashville, TN.,Department of Radiology and Radiological Sciences (M.J.D.), Vanderbilt University Medical Center, Nashville, TN
| | - Chelsea A Lee
- Department of Psychology and Human Development, Vanderbilt University, Nashville, TN (K.V.P., B.E.C., R.E.S., A.E.C.).,Department of Pediatrics (C.A.L., L.C.J., M.R.D.), Vanderbilt University Medical Center, Nashville, TN.,Department of Internal Medicine (A.A.K.), Vanderbilt University Medical Center, Nashville, TN.,Department of Radiology and Radiological Sciences (M.J.D.), Vanderbilt University Medical Center, Nashville, TN
| | - Adetola A Kassim
- Department of Psychology and Human Development, Vanderbilt University, Nashville, TN (K.V.P., B.E.C., R.E.S., A.E.C.).,Department of Pediatrics (C.A.L., L.C.J., M.R.D.), Vanderbilt University Medical Center, Nashville, TN.,Department of Internal Medicine (A.A.K.), Vanderbilt University Medical Center, Nashville, TN.,Department of Radiology and Radiological Sciences (M.J.D.), Vanderbilt University Medical Center, Nashville, TN
| | - Michael R DeBaun
- Department of Psychology and Human Development, Vanderbilt University, Nashville, TN (K.V.P., B.E.C., R.E.S., A.E.C.).,Department of Pediatrics (C.A.L., L.C.J., M.R.D.), Vanderbilt University Medical Center, Nashville, TN.,Department of Internal Medicine (A.A.K.), Vanderbilt University Medical Center, Nashville, TN.,Department of Radiology and Radiological Sciences (M.J.D.), Vanderbilt University Medical Center, Nashville, TN
| | - Manus J Donahue
- Department of Psychology and Human Development, Vanderbilt University, Nashville, TN (K.V.P., B.E.C., R.E.S., A.E.C.).,Department of Pediatrics (C.A.L., L.C.J., M.R.D.), Vanderbilt University Medical Center, Nashville, TN.,Department of Internal Medicine (A.A.K.), Vanderbilt University Medical Center, Nashville, TN.,Department of Radiology and Radiological Sciences (M.J.D.), Vanderbilt University Medical Center, Nashville, TN
| | - Lori C Jordan
- Department of Psychology and Human Development, Vanderbilt University, Nashville, TN (K.V.P., B.E.C., R.E.S., A.E.C.).,Department of Pediatrics (C.A.L., L.C.J., M.R.D.), Vanderbilt University Medical Center, Nashville, TN.,Department of Internal Medicine (A.A.K.), Vanderbilt University Medical Center, Nashville, TN.,Department of Radiology and Radiological Sciences (M.J.D.), Vanderbilt University Medical Center, Nashville, TN
| |
Collapse
|
22
|
Regi SS, Livingstone RS, Kandagaddala M, Poonnoose P, Gibikote S, Keshava SN, Srivastava A. Ultrasound and magnetic resonance imaging for the detection of blood: An ex-vivo study. Haemophilia 2021; 27:488-493. [PMID: 33780101 DOI: 10.1111/hae.14303] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 02/16/2021] [Accepted: 03/15/2021] [Indexed: 10/21/2022]
Abstract
OBJECTIVES Early detection of bleeding into a joint is crucial in patients with haemophilia. This study was designed to evaluate the sensitivity of ultrasonography (USG) and magnetic resonance imaging (MRI) to detect the presence of blood in small concentrations in a simulated model to mimic joint bleeding. MATERIALS AND METHODS Different concentrations of blood in plasma, varying from 0.1% to 45%, were collected in 10-ml plastic syringes and imaged using 12 and 18 MHz USG transducers and with 1.5T and 3T MRI scanners, at different intervals of time following dilution. The images were scored for the presence of blood by four experienced radiologists who were blinded to the concentration of blood. RESULTS Within the first 2 h, the 18 MHz transducer was able to detect blood consistently up to 0.5%, whereas the 12 MHz transducer could consistently identify blood up to 1.4%. After the first 12 h, both transducers were able to detect blood up to 0.5% concentration. However, at concentrations below 0.5%, there was discordance in the ability to detect blood, with both transducers. There was no correlation between the signal intensities of MRI images and concentration of blood, at different time intervals, irrespective of the magnetic field strength. CONCLUSIONS Detection of blood using the USG is dependent on variables such as the concentration of blood, frequency of the transducer used and timing of the imaging. As the concentration of blood decreases below 0.5%, the discordance between the observers increases, implying that the detection limit of USG affects its reliability at lower concentrations of blood. Caution is urged while interpreting USG imaging studies for the detection of blood in symptomatic joints.
Collapse
Affiliation(s)
- Soumya Susan Regi
- Division of Clinical Radiology, Christian Medical College, Vellore, India
| | | | | | - Pradeep Poonnoose
- Department of Orthopaedic Surgery, Christian Medical College, Vellore, India
| | - Sridhar Gibikote
- Division of Clinical Radiology, Christian Medical College, Vellore, India
| | | | - Alok Srivastava
- Department of Hematology, Christian Medical College, Vellore, India
| |
Collapse
|
23
|
Qi Y, He J. Neurophysiologic Profiling of At-Risk Low and Very Low Birth-Weight Infants Using Magnetic Resonance Imaging. Front Physiol 2021; 12:638868. [PMID: 33833688 PMCID: PMC8021729 DOI: 10.3389/fphys.2021.638868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 03/02/2021] [Indexed: 11/13/2022] Open
Abstract
Low birth-weight (LBW) and very low birth-weight (VLBW) newborns have increased risks of brain injuries, growth failure, motor difficulties, developmental coordination disorders or delay, and adult-onset vascular diseases. However, relatively little is known of the neurobiologic underpinnings. To clarify the pathophysiologic vulnerabilities of such neonates, we applied several advanced techniques for assessing brain physiology, namely T2-relaxation-under-spin-tagging (TRUST) magnetic resonance imaging (MRI) and phase-contrast (PC) MRI. This enabled quantification of oxygen extraction fraction (OEF), global cerebral blood flow (CBF), and cerebral metabolic rate of oxygen (CMRO2). A total of 50 neonates (LBW-VLBW, 41; term controls, 9) participated in this study. LBW-VLBW neonates were further stratified as those with (LBW-VLBW-a, 24) and without (LBW-VLBW-n, 17) structural MRI (sMRI) abnormalities. TRUST and PC MRI studies were undertaken to determine OEF, CBF, and CMRO2. Ultimately, CMRO2 proved significantly lower (p = 0.01) in LBW-VLBW (vs term) neonates, both LBW-VLBW-a and LBW-VLBW-n subsets showing significantly greater physiologic deficits than term controls (p = 0.03 and p = 0.04, respectively). CMRO2 and CBF in LBW-VLBW-a and LBW-VLBW-n subsets did not differ significantly (p > 0.05), although OEF showed a tendency to diverge (p = 0.15). However, OEF values in the LBW-VLBW-n subset differed significantly from those of term controls (p = 0.02). Compared with brain volume or body weight, these physiologic parameters yield higher area-under-the-curve (AUC) values for distinguishing neonates of the LBW-VLBW-a subset. The latter displayed distinct cerebral metabolic and hemodynamic, whereas changes were marginal in the LBW-VLBW-n subset (i.e., higher OEF and lower CBF and CMRO2) by comparison. Physiologic imaging may therefore be useful in identifying LBW-VLBW newborns at high risk of irreversible brain damage.
Collapse
Affiliation(s)
- Ying Qi
- Department of Radiology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Jingni He
- Department of Surgery, Shengjing Hospital of China Medical University, Shenyang, China
| |
Collapse
|
24
|
Zheng Q, Freeman CW, Hwang M. Sex-related differences in arterial spin-labelled perfusion of metabolically active brain structures in neonatal hypoxic-ischaemic encephalopathy. Clin Radiol 2021; 76:342-347. [PMID: 33579516 DOI: 10.1016/j.crad.2020.12.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 12/24/2020] [Indexed: 10/22/2022]
Abstract
AIM To investigate the sex-related differences in arterial spin-labelled (ASL) perfusion of metabolically active brain structures in neonatal hypoxic-ischaemic encephalopathy (HIE). MATERIALS AND METHODS Seventy-three term neonates were identified for a retrospective case-control study following an institutional review board (IRB) approved protocol. The cerebral pulsed arterial spin labelling values were compared by permutation test to identify metabolically active brain structures with significant perfusion changes between 10 male controls and eight female controls, and between 31 HIE males and 24 HIE females. RESULTS In the perfusion comparison between HIE male and female neonates, significantly lower perfusion was found in the thalamus in males (p=0.02). The other brain clusters, including basal ganglia, hippocampus cluster, cingulate gyrus cluster, brainstem cluster, sensorimotor cortex cluster, and cerebellum and peduncle cluster, demonstrated no significant differences between HIE males and females. In the perfusion comparison between male and female controls, there were no significant perfusion changes in those brain clusters. CONCLUSION Brain perfusion in neonatal HIE differs between males and females in the thalamus, a metabolically active region within neonates, with males demonstrating lower perfusion. This difference in perfusion may reflect sex-related disparities in response to and recovery from hypoxic-ischaemic events.
Collapse
Affiliation(s)
- Q Zheng
- School of Computer and Control Engineering, Yantai University, Yantai, China
| | - C W Freeman
- Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA
| | - M Hwang
- Department of Radiology, Children's Hospital of Philadelphia, Philadelphia, PA, USA; Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA.
| |
Collapse
|
25
|
Jiang D, Deng S, Franklin CG, O’Boyle M, Zhang W, Heyl BL, Pan L, Jerabek PA, Fox PT, Lu H. Validation of T 2 -based oxygen extraction fraction measurement with 15 O positron emission tomography. Magn Reson Med 2021; 85:290-297. [PMID: 32643207 PMCID: PMC9973312 DOI: 10.1002/mrm.28410] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/19/2020] [Accepted: 06/11/2020] [Indexed: 12/20/2022]
Abstract
PURPOSE To evaluate the accuracy of T2 -based whole-brain oxygen extraction fraction (OEF) estimation by comparing it with gold standard 15 O-PET measurements. METHODS Sixteen healthy adult subjects underwent MRI and 15 O-PET OEF measurements on the same day. On MRI, whole-brain OEF was quantified by T2 -relaxation-under-spin-tagging (TRUST) MRI, based on subject-specific hematocrit. The TRUST OEF was compared to the whole-brain averaged OEF produced by 15 O-PET. Agreement between TRUST and 15 O-PET whole-brain OEF measurements was examined in terms of intraclass correlation coefficient (ICC) and in absolute OEF values. In a subset of 10 subjects, test-retest reproducibility of whole-brain OEF was also evaluated and compared between the two modalities. RESULTS Across the 16 subjects, the mean whole-brain OEF of TRUST and 15 O-PET were 36.44 ± 4.07% and 36.45 ± 3.65%, respectively, showing no difference between the two modalities (P = .99). TRUST whole-brain OEF strongly correlated with that of 15 O-PET (N = 16, ICC = 0.90, P = 4 × 10-7 ). The coefficient-of-variation of TRUST and 15 O-PET whole-brain OEF measurements were 1.79 ± 0.67% and 2.06 ± 1.55%, respectively, showing no difference between the two modalities (N = 10, P = .64). Further analyses on the effect of hematocrit revealed that correlation between PET OEF and TRUST OEF with assumed hematocrit remained significant (ICC = 0.8, P < 2 × 10-5 ). CONCLUSION Whole-brain OEF measured by TRUST was in excellent agreement with gold standard 15 O-PET, with highly comparable accuracy and reproducibility. These findings suggest that TRUST MRI can provide accurate quantification of whole-brain OEF noninvasively.
Collapse
Affiliation(s)
- Dengrong Jiang
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Shengwen Deng
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Crystal G. Franklin
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Michael O’Boyle
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Wei Zhang
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Betty L. Heyl
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Li Pan
- Siemens Healthineers, Baltimore, Maryland, USA
| | - Paul A. Jerabek
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Peter T. Fox
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA.,Department of Radiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA,South Texas Veterans Health Care System, San Antonio, Texas, USA
| | - Hanzhang Lu
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, Maryland, USA
| |
Collapse
|
26
|
Zheng Q, Viaene AN, Freeman CW, Hwang M. Radiologic-pathologic evidence of brain injury: hypoperfusion in the Papez circuit results in poor neurodevelopmental outcomes in neonatal hypoxic ischemic encephalopathy. Childs Nerv Syst 2021; 37:63-68. [PMID: 32661642 PMCID: PMC7796967 DOI: 10.1007/s00381-020-04795-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 07/08/2020] [Indexed: 01/05/2023]
Abstract
PURPOSE To provide radiologic-pathologic correlation of brain injury in the Papez circuit in hypoxic-ischemic encephalopathy (HIE) neonates and correlate radiologic findings with long-term neurodevelopmental outcomes. METHODS Twenty full-term HIE neonates were evaluated. Cerebral blood flow (CBF) values, obtained through pulsed arterial spin labeling (ASL) perfusion-weighted MRI, were compared by permutation test to identify brain regions with statistically significant perfusion changes between 14 HIE neonates without evidence of developmental delay by Bayley-III (mean age 8.2 ± 7.2 days) and 6 HIE neonates with evidence of developmental delay (mean age 13.1 ± 8.0 days). Four histopathologic studies on specimens were taken from post-mortem brains of another group of infants (mean age 10 ± 6.8 days) with HIE. The infants were not the same ones who had MRIs. RESULTS Significantly decreased perfusion in Papez circuit was found in HIE neonates with developmental delay compared with HIE neonates without delay. Decreased ASL perfusion values were seen in Papez circuit structures of the fornix (p = 0.002), entorhinal cortex (p = 0.048), amygdala (p = 0.036), hippocampus (p = 0.033), and thalamus (p = 0.036). In autopsy specimens of neonates with HIE, anoxic (eosinophilic) neurons, reactive astrocytes, and white matter rarefaction were observed in these regions, providing pathology correlation to the imaging findings of HIE. CONCLUSION The Papez circuit is susceptible to hypoxic-ischemic injury in neonates as demonstrated by perfusion-weighted imaging and histopathology. This sheds new light onto a possible non-familial mechanism of neuropsychiatric disease evolution initiated in the infant period and raises the potential for early identification of at-risk children.
Collapse
Affiliation(s)
- Qiang Zheng
- School of Computer and Control Engineering, Yantai University, Yantai, China
| | - Angela N. Viaene
- Department of Pathology and Laboratory Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA,Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Colbey W. Freeman
- Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA
| | - Misun Hwang
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, Philadelphia, PA, 19104, USA. .,Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA.
| |
Collapse
|
27
|
Anderson KB, Andersen AS, Hansen DN, Sinding M, Peters DA, Frøkjaer JB, Sørensen A. Placental transverse relaxation time (T2) estimated by MRI: Normal values and the correlation with birthweight. Acta Obstet Gynecol Scand 2020; 100:934-940. [PMID: 33258106 DOI: 10.1111/aogs.14057] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 11/20/2020] [Accepted: 11/24/2020] [Indexed: 02/05/2023]
Abstract
INTRODUCTION Placental transverse relaxation time (T2) assessed by MRI may have the potential to improve the antenatal identification of small for gestational age. The aims of this study were to provide normal values of placental T2 in relation to gestational age at the time of MRI and to explore the correlation between placental T2 and birthweight. MATERIAL AND METHODS A mixed cohort of 112 singleton pregnancies was retrieved from our placental MRI research database. MRI was performed at 23.6-41.3 weeks of gestation in a 1.5T system (TE (8): 50-440 ms, TR: 4000 ms). Normal pregnancies were defined by uncomplicated pregnancies with normal obstetric outcome and birthweight deviation within ±1 SD of the expected for gestational age. The correlation between placental T2 and birthweight was investigated using the following outcomes; small for gestational age (birthweight ≤-2 SD of the expected for gestational age) and birthweight deviation (birthweight Z-scores). RESULTS In normal pregnancies (n = 27), placenta T2 showed a significant negative linear correlation with gestational age (r = -.91, P = .0001) being 184 ms ± 15.94 ms (mean ± SD) at 20 weeks of gestation and 89 ms ± 15.94 ms at 40 weeks of gestation. Placental T2 was significantly reduced among small-for-gestational-age pregnancies (mean Z-score -1.95, P < .001). Moreover, we found a significant positive correlation between placenta T2 deviation (Z-score) and birthweight deviation (Z-score) (R2 = .26, P = .0001). CONCLUSIONS This study provides normal values of placental T2 to be used in future studies on placental MRI. Placental T2 is closely related to birthweight and may improve the antenatal identification of small-for-gestational-age pregnancies.
Collapse
Affiliation(s)
- Kristi B Anderson
- Department of Pathology, Aalborg University Hospital, Aalborg, Denmark
| | - Anna S Andersen
- Department of Obstetrics and Gynecology, Aalborg University Hospital, Aalborg, Denmark
| | - Ditte N Hansen
- Department of Obstetrics and Gynecology, Aalborg University Hospital, Aalborg, Denmark.,Department of Clinical Medicine, Aalborg University, Aalborg, Denmark
| | - Marianne Sinding
- Department of Obstetrics and Gynecology, Aalborg University Hospital, Aalborg, Denmark.,Department of Clinical Medicine, Aalborg University, Aalborg, Denmark
| | - David A Peters
- Department of Clinical Engineering, Central Denmark Region, Aarhus, Denmark
| | - Jens B Frøkjaer
- Department of Clinical Medicine, Aalborg University, Aalborg, Denmark.,Department of Radiology, Aalborg University Hospital, Aalborg, Denmark
| | - Anne Sørensen
- Department of Obstetrics and Gynecology, Aalborg University Hospital, Aalborg, Denmark.,Department of Clinical Medicine, Aalborg University, Aalborg, Denmark
| |
Collapse
|
28
|
Obmann VC, Berzigotti A, Catucci D, Ebner L, Gräni C, Heverhagen JT, Christe A, Huber AT. T1 mapping of the liver and the spleen in patients with liver fibrosis-does normalization to the blood pool increase the predictive value? Eur Radiol 2020; 31:4308-4318. [PMID: 33313965 PMCID: PMC8128789 DOI: 10.1007/s00330-020-07447-8] [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: 06/09/2020] [Revised: 09/03/2020] [Accepted: 10/29/2020] [Indexed: 02/07/2023]
Abstract
Purpose To analyze whether the T1 relaxation time of the liver is a good predictor of significant liver fibrosis and whether normalization to the blood pool improves the predictive value. Methods This prospective study was conducted between 03/2016 and 02/2018. One hundred seventy-three patients underwent multiparametric liver MRI at 3 T. The T1 relaxation time was measured in the liver and the spleen, in the aorta, the portal vein, and the inferior vena cava (IVC). T1 relaxation times with and without normalization to the blood pool were compared between patients with (n = 26) and without (n = 141) significant liver fibrosis, based on a cutoff value of 3.5 kPa in MRE as the noninvasive reference standard. For statistics, Student’s t test, receiver operating characteristic (ROC) curve analysis, and Pearson’s correlation were used. Results The T1 relaxation time of the liver was significantly longer in patients with liver fibrosis, both with and without blood pool normalization (p < 0.001). T1 relaxation time of the liver allowed prediction of significant liver fibrosis (AUC = 0.88), while normalization to the IVC resulted in a slightly lower performance (AUC = 0.82). The lowest performance was achieved when the T1 relaxation times of the liver were normalized to the aorta (AUC = 0.66) and to the portal vein (AUC = 0.62). The T1 relaxation time of the spleen detected significant liver fibrosis with an AUC of 0.68, and 0.51–0.64 with normalization to the blood pool. Conclusion The T1 relaxation time of the liver is a good predictor of significant liver fibrosis. However, normalization of the blood pool did not improve the predictive value. Key Points • The T1 relaxation time of the liver is a good predictor of significant liver fibrosis. • Normalization to the blood pool did not improve the predictive value of T1 mapping. • If the blood pool normalization was weighted 30% to the aorta and 70% to the portal vein, the performance was better than normalization to the aorta alone but still lower than normalization to the IVC.
Collapse
Affiliation(s)
- Verena Carola Obmann
- Department of Diagnostic, Interventional and Pediatric Radiology, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010, Bern, Switzerland
| | - Annalisa Berzigotti
- Hepatology, Department of Visceral Surgery and Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Damiano Catucci
- Department of Diagnostic, Interventional and Pediatric Radiology, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010, Bern, Switzerland
| | - Lukas Ebner
- Department of Diagnostic, Interventional and Pediatric Radiology, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010, Bern, Switzerland
| | - Christoph Gräni
- Department of Cardiology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Johannes Thomas Heverhagen
- Department of Diagnostic, Interventional and Pediatric Radiology, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010, Bern, Switzerland
| | - Andreas Christe
- Department of Diagnostic, Interventional and Pediatric Radiology, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010, Bern, Switzerland
| | - Adrian Thomas Huber
- Department of Diagnostic, Interventional and Pediatric Radiology, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010, Bern, Switzerland.
| |
Collapse
|
29
|
Cao D, Kang N, Pillai JJ, Miao X, Paez A, Xu X, Xu J, Li X, Qin Q, Van Zijl PCM, Barker P, Hua J. Fast whole brain MR imaging of dynamic susceptibility contrast changes in the cerebrospinal fluid (cDSC MRI). Magn Reson Med 2020; 84:3256-3270. [PMID: 32621291 DOI: 10.1002/mrm.28389] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 05/27/2020] [Accepted: 06/01/2020] [Indexed: 01/28/2023]
Abstract
PURPOSE The circulation of cerebrospinal fluid (CSF) is closely associated with many aspects of brain physiology. When gadolinium(Gd)-based contrast is administered intravenously, pre- and post-contrast MR signal changes can often be observed in the CSF at certain locations within the intra-cranial space, mainly due to the lack of a blood-brain barrier in the dural blood vessels. This study aims to develop and systemically optimize MRI sequences that can detect dynamic signal changes in the CSF after Gd administration with a sub-millimeter spatial resolution, a temporal resolution of <10 s, and whole brain coverage. METHODS Bloch simulations were performed to determine optimal imaging parameters for maximum CSF contrast before and after Gd injection. Simulations were validated with phantom scans. An optimized turbo-spin-echo (TSE) sequence was performed on healthy volunteers on 3T and 7T. RESULTS Simulation results agreed well with phantom scans. In human scans, dynamic signal changes after Gd injection in the CSF were detected at several locations where cerebral lymphatic vessels were identified in previous studies. The concentration of Gd in CSF in these regions was estimated to be approximately 0.2 mmol/L. CONCLUSION Dynamic signal changes induced by the distribution of Gd in the CSF can be detected in healthy human subjects with an optimized TSE sequence. The proposed methodology does not rely on any particular theory on CSF circulation. We expect it to be useful for studies on CSF circulation and cerebral lymphatic vessels in the brain.
Collapse
Affiliation(s)
- Di Cao
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA.,Neurosection, Division of MRI Research, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
| | - Ningdong Kang
- Division of Neuroradiology, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jay J Pillai
- Division of Neuroradiology, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Xinyuan Miao
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA.,Neurosection, Division of MRI Research, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Adrian Paez
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
| | - Xiang Xu
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA.,Neurosection, Division of MRI Research, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jiadi Xu
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA.,Neurosection, Division of MRI Research, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Xu Li
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA.,Neurosection, Division of MRI Research, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Qin Qin
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA.,Neurosection, Division of MRI Research, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Peter C M Van Zijl
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA.,Neurosection, Division of MRI Research, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Peter Barker
- Division of Neuroradiology, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jun Hua
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA.,Neurosection, Division of MRI Research, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| |
Collapse
|
30
|
Hermann I, Uhrig T, Chacon-Caldera J, Akçakaya M, Schad LR, Weingärtner S. Towards measuring the effect of flow in blood T 1 assessed in a flow phantom and in vivo. Phys Med Biol 2020; 65:095001. [PMID: 32160594 DOI: 10.1088/1361-6560/ab7ef1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Measurement of the blood T 1 time using conventional myocardial T 1 mapping methods has gained clinical significance in the context of extracellular volume (ECV) mapping and synthetic hematocrit (Hct). However, its accuracy is potentially compromised by in-flow of non-inverted/non-saturated spins and in-flow of spins which are not partially saturated from previous imaging pulses. Bloch simulations were used to analyze various flow effects separately. T 1 measurements of gadolinium doped water were performed using a flow phantom with adjustable flow velocities at 3 T. Additionally, in vivo blood T 1 measurements were performed in 6 healthy subjects (26 ± 5 years, 2 female). To study the T 1 time as a function of the instantaneous flow velocity, T 1 times were evaluated in an axial imaging slice of the descending aorta. Velocity encoded cine measurements were performed to quantify the flow velocity throughout the cardiac cycle. Simulation results show more than 30% loss in accuracy for 10% non-prepared in-flowing spins. However, in- and out-flow to the imaging plane only demonstrated minor impact on the T 1 time. Phantom T 1 times were decreased by up to 200 ms in the flow phantom, due to in-flow of non-prepared spins. High flow velocities cause in-flow of spins that lack partial saturation from the imaging pulses but only lead to negligible T 1 time deviation (less than 30 ms). In vivo measurements confirm a substantial variation of the T 1 time depending on the flow velocity. The highest aortic T 1 times are observed at the time point of minimal flow with increased flow velocity leading to reduction of the measured T 1 time by up to [Formula: see text] at peak velocity. In this work we attempt to dissect the effects of flow on T 1 times, by using simulations, well-controlled, simplified phantom setup and the linear flow pattern in the descending aorta in vivo.
Collapse
Affiliation(s)
- Ingo Hermann
- Magnetic Resonance Systems Lab, Department of Imaging Physics, Delft University of Technology, Lorentzweg 1, 2628 Delft, Netherlands. Computer Assisted Clinical Medicine, University Medical Center Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany
| | | | | | | | | | | |
Collapse
|
31
|
Harteveld AA, Hutter J, Franklin SL, Jackson LH, Rutherford M, Hajnal JV, van Osch MJP, Bos C, De Vita E. Systematic evaluation of velocity-selective arterial spin labeling settings for placental perfusion measurement. Magn Reson Med 2020; 84:1828-1843. [PMID: 32141655 PMCID: PMC7384055 DOI: 10.1002/mrm.28240] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 02/04/2020] [Accepted: 02/10/2020] [Indexed: 01/15/2023]
Abstract
Purpose Placental function is key for successful human pregnancies. Perfusion may be a sensitive marker for the in vivo assessment of placental function. Arterial spin labeling (ASL) MRI enables noninvasive measurement of tissue perfusion and it was recently suggested that ASL with velocity‐selective (VS) labeling could be advantageous in the placenta. We systematically evaluated essential VS‐ASL sequence parameters to determine optimal settings for efficient placental perfusion measurements. Methods Eleven pregnant women were scanned at 3T using VS‐ASL with 2D multislice echo planar imaging (EPI)‐readout. One reference VS‐ASL scan was acquired in all subjects; within subgroups the following parameters were systematically varied: cutoff velocity, velocity encoding direction, and inflow time. Visual evaluation and region of interest analyses were performed to compare perfusion signal differences between acquisitions. Results In all subjects, a perfusion pattern with clear hyperintense focal regions was observed. Perfusion signal decreased with inflow time and cutoff velocity. Subject‐specific dependence on velocity encoding direction was observed. High temporal signal‐to‐noise ratios with high contrast on the perfusion images between the hyperintense regions and placental tissue were seen at ~1.6 cm/s cutoff velocity and ~1000 ms inflow time. Evaluation of measurements at multiple inflow times revealed differences in blood flow dynamics between placental regions. Conclusion Placental perfusion measurements are feasible at 3T using VS‐ASL with 2D multislice EPI‐readout. A clear dependence of perfusion signal on VS labeling parameters and inflow time was demonstrated. Whereas multiple parameter combinations may advance the interpretation of placental circulation dynamics, this study provides a basis to select an effective set of parameters for the observation of placenta perfusion natural history and its potential pathological changes.
Collapse
Affiliation(s)
- Anita A Harteveld
- Department of Radiology, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
| | - Jana Hutter
- Biomedical Engineering, School of Imaging Sciences and Biomedical Engineering, King's College London, London, United Kingdom
| | - Suzanne L Franklin
- Department of Radiology, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands.,C.J. Gorter Center for high field MRI, Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands
| | - Laurence H Jackson
- Biomedical Engineering, School of Imaging Sciences and Biomedical Engineering, King's College London, London, United Kingdom
| | - Mary Rutherford
- Biomedical Engineering, School of Imaging Sciences and Biomedical Engineering, King's College London, London, United Kingdom
| | - Joseph V Hajnal
- Biomedical Engineering, School of Imaging Sciences and Biomedical Engineering, King's College London, London, United Kingdom
| | - Matthias J P van Osch
- C.J. Gorter Center for high field MRI, Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands
| | - Clemens Bos
- Department of Radiology, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
| | - Enrico De Vita
- Biomedical Engineering, School of Imaging Sciences and Biomedical Engineering, King's College London, London, United Kingdom
| |
Collapse
|
32
|
Xu J, Duan AQ, Marini D, Lim JM, Keunen J, Portnoy S, Sled JG, McCrindle BW, Kingdom J, Macgowan CK, Seed M. The utility of MRI for measuring hematocrit in fetal anemia. Am J Obstet Gynecol 2020; 222:81.e1-81.e13. [PMID: 31306649 DOI: 10.1016/j.ajog.2019.07.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 07/08/2019] [Accepted: 07/09/2019] [Indexed: 12/19/2022]
Abstract
BACKGROUND Doppler ultrasound measurements of the peak systolic velocity of the middle cerebral artery can be used to noninvasively diagnose fetal anemia but are less precise following fetal blood transfusion and in late gestation. We have previously demonstrated the feasibility of estimating fetal hematocrit in vitro using magnetic resonance imaging relaxation times. Here we report the use of magnetic resonance imaging as a noninvasive tool to accurately detect fetal anemia in vivo. OBJECTIVES This study has 2 objectives: (1) to determine the feasibility and accuracy of magnetic resonance imaging in estimating hematocrit in anemic fetuses and (2) to compare magnetic resonance imaging and middle cerebral artery Doppler in detecting moderate to severe fetal anemia. STUDY DESIGN Fetuses undergoing fetal blood sampling or transfusion underwent magnetic resonance imaging examinations prior to and following their procedures at 1.5 Tesla (Siemens Avanto). A modified Look-Locker inversion pulse sequence and T2 preparation sequence were applied for T1 and T2 mapping of the intrahepatic umbilical vein. Estimated fetal hematocrit was calculated using a combination of T1 and T2 values and compared with conventional hematocrit obtained from fetal blood samples and middle cerebral artery Doppler measurements. RESULTS Twenty-three fetuses were assessed during 33 magnetic resonance imaging scans. The mean absolute difference between the laboratory and magnetic resonance imaging-estimated hematocrit was 0.06 ± 0.05 with a correlation of 0.77 (P < .001) determined by a multilevel, mixed-effects model adjusting for the repeated measurements from the same participants, multiple gestation pregnancies, and the scan type (ie, before or after transfusion scan). Bland-Altman analysis revealed a systematic bias of -0.03 between the magnetic resonance imaging and fetal blood sampling measurements. Magnetic resonance imaging and middle cerebral artery Doppler had similar sensitivities of approximately 90% to detect moderate to severe anemia. However, magnetic resonance imaging had a higher specificity (93% [13/14], 95% confidence interval, 66-100%) than Doppler (71% [10/14], 95% confidence interval, 42-92%). CONCLUSION Moderate to severe fetal anemia can be detected noninvasively by magnetic resonance imaging with high sensitivity and specificity. Our results suggest an adjunct role for magnetic resonance imaging in fetuses with suspected anemia, particularly following previous transfusion and in late gestation.
Collapse
|
33
|
Zheng Q, Martin-Saavedra JS, Saade-Lemus S, Vossough A, Zuccoli G, Gonçalves FG, Freeman CW, Ouyang M, Singh V, Padula MA, Demauro SB, Flibotte J, Eichenwald EC, Detre JA, Sze RW, Huang H, Hwang M. Cerebral Pulsed Arterial Spin Labeling Perfusion Weighted Imaging Predicts Language and Motor Outcomes in Neonatal Hypoxic-Ischemic Encephalopathy. Front Pediatr 2020; 8:576489. [PMID: 33102411 PMCID: PMC7546822 DOI: 10.3389/fped.2020.576489] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 08/21/2020] [Indexed: 12/17/2022] Open
Abstract
Rationale and Objectives: To compare cerebral pulsed arterial spin labeling (PASL) perfusion among controls, hypoxic ischemic encephalopathy (HIE) neonates with normal conventional MRI(HIE/MRI⊕), and HIE neonates with abnormal conventional MRI(HIE/MRI⊖). To create a predictive machine learning model of neurodevelopmental outcomes using cerebral PASL perfusion. Materials and Methods: A total of 73 full-term neonates were evaluated. The cerebral perfusion values were compared by permutation test to identify brain regions with significant perfusion changes among 18 controls, 40 HIE/MRI⊖ patients, and 15 HIE/MRI⊕ patients. A machine learning model was developed to predict neurodevelopmental outcomes using the averaged perfusion in those identified brain regions. Results: Significantly decreased PASL perfusion in HIE/MRI⊖ group, when compared with controls, were found in the anterior corona radiata, caudate, superior frontal gyrus, precentral gyrus. Both significantly increased and decreased cerebral perfusion changes were detected in HIE/MRI⊕ group, when compared with HIE/MRI⊖ group. There were no significant perfusion differences in the cerebellum, brainstem and deep structures of thalamus, putamen, and globus pallidus among the three groups. The machine learning model demonstrated significant correlation (p < 0.05) in predicting language(r = 0.48) and motor(r = 0.57) outcomes in HIE/MRI⊖ patients, and predicting language(r = 0.76), and motor(r = 0.53) outcomes in an additional group combining HIE/MRI⊖ and HIE/MRI⊕. Conclusion: Perfusion MRI can play an essential role in detecting HIE regardless of findings on conventional MRI and predicting language and motor outcomes in HIE survivors. The perfusion changes may also reveal important insights into the reperfusion response and intrinsic autoregulatory mechanisms. Our results suggest that perfusion imaging may be a useful adjunct to conventional MRI in the evaluation of HIE in clinical practice.
Collapse
Affiliation(s)
| | | | | | - Arastoo Vossough
- Children's Hospital of Philadelphia, Philadelphia, PA, United States.,University of Pennsylvania, Philadelphia, PA, United States
| | - Giulio Zuccoli
- Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | | | | | - Minhui Ouyang
- Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - Varun Singh
- Thomas Jefferson University, Philadelphia, PA, United States
| | - Michael A Padula
- Children's Hospital of Philadelphia, Philadelphia, PA, United States.,University of Pennsylvania, Philadelphia, PA, United States
| | - Sara B Demauro
- Children's Hospital of Philadelphia, Philadelphia, PA, United States.,University of Pennsylvania, Philadelphia, PA, United States
| | - John Flibotte
- Children's Hospital of Philadelphia, Philadelphia, PA, United States.,University of Pennsylvania, Philadelphia, PA, United States
| | - Eric C Eichenwald
- Children's Hospital of Philadelphia, Philadelphia, PA, United States.,University of Pennsylvania, Philadelphia, PA, United States
| | - John A Detre
- University of Pennsylvania, Philadelphia, PA, United States
| | - Raymond Wang Sze
- Children's Hospital of Philadelphia, Philadelphia, PA, United States.,University of Pennsylvania, Philadelphia, PA, United States
| | - Hao Huang
- Children's Hospital of Philadelphia, Philadelphia, PA, United States.,University of Pennsylvania, Philadelphia, PA, United States
| | - Misun Hwang
- Children's Hospital of Philadelphia, Philadelphia, PA, United States.,University of Pennsylvania, Philadelphia, PA, United States
| |
Collapse
|
34
|
Turk EA, Stout JN, Ha C, Luo J, Gagoski B, Yetisir F, Golland P, Wald LL, Adalsteinsson E, Robinson JN, Roberts DJ, Barth WH, Grant PE. Placental MRI: Developing Accurate Quantitative Measures of Oxygenation. Top Magn Reson Imaging 2019; 28:285-297. [PMID: 31592995 PMCID: PMC7323862 DOI: 10.1097/rmr.0000000000000221] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The Human Placenta Project has focused attention on the need for noninvasive magnetic resonance imaging (MRI)-based techniques to diagnose and monitor placental function throughout pregnancy. The hope is that the management of placenta-related pathologies would be improved if physicians had more direct, real-time measures of placental health to guide clinical decision making. As oxygen alters signal intensity on MRI and oxygen transport is a key function of the placenta, many of the MRI methods under development are focused on quantifying oxygen transport or oxygen content of the placenta. For example, measurements from blood oxygen level-dependent imaging of the placenta during maternal hyperoxia correspond to outcomes in twin pregnancies, suggesting that some aspects of placental oxygen transport can be monitored by MRI. Additional methods are being developed to accurately quantify baseline placental oxygenation by MRI relaxometry. However, direct validation of placental MRI methods is challenging and therefore animal studies and ex vivo studies of human placentas are needed. Here we provide an overview of the current state of the art of oxygen transport and quantification with MRI. We suggest that as these techniques are being developed, increased focus be placed on ensuring they are robust and reliable across individuals and standardized to enable predictive diagnostic models to be generated from the data. The field is still several years away from establishing the clinical benefit of monitoring placental function in real time with MRI, but the promise of individual personalized diagnosis and monitoring of placental disease in real time continues to motivate this effort.
Collapse
Affiliation(s)
- Esra Abaci Turk
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children’s Hospital, MA, USA
| | - Jeffrey N. Stout
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children’s Hospital, MA, USA
| | - Christopher Ha
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children’s Hospital, MA, USA
| | - Jie Luo
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Borjan Gagoski
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children’s Hospital, MA, USA
| | - Filiz Yetisir
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children’s Hospital, MA, USA
| | - Polina Golland
- Computer Science and Artificial Intelligence Laboratory (CSAIL), Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Lawrence L. Wald
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Elfar Adalsteinsson
- Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology, Cambridge, MA, United States
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Julian N. Robinson
- Department of Obstetrics and Gynecology, Brigham and Women’s Hospital, Boston, USA
| | | | - William H. Barth
- Maternal-Fetal Medicine, Obstetrics and Gynecology, Massachusetts General Hospital, Boston, MA, USA
| | - P. Ellen Grant
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children’s Hospital, MA, USA
| |
Collapse
|
35
|
Li W, Xu X, Liu P, Strouse JJ, Casella JF, Lu H, van Zijl PCM, Qin Q. Quantification of whole-brain oxygenation extraction fraction and cerebral metabolic rate of oxygen consumption in adults with sickle cell anemia using individual T 2 -based oxygenation calibrations. Magn Reson Med 2019; 83:1066-1080. [PMID: 31483528 DOI: 10.1002/mrm.27972] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 07/18/2019] [Accepted: 08/05/2019] [Indexed: 12/23/2022]
Abstract
PURPOSE To evaluate different T2 -oxygenation calibrations for estimating venous oxygenation in people with sickle cell anemia (SCA). METHODS Blood T2 values were measured at 3 T in the internal jugular veins of 12 healthy volunteers and 11 SCA participants with no history of stroke, recent transfusion, or renal impairment. T2 -oxygenation relationships of both sickled and normal blood samples were calibrated individually and compared with values generated from published models. After converting venous T2 values to venous oxygenation, whole-brain oxygen extraction fraction and cerebral metabolic rate of oxygen were calculated. RESULTS Sickle blood samples' oxygenation values calculated from our individual calibrations agreed well with measurements using a blood analyzer, whereas previous T2 calibrations based on normal blood samples showed 13%-19% underestimation. Meanwhile, oxygenation values calculated from previous grouped T2 calibration for sickle blood agreed well with experimental measurement on averaged values, but showed up to 20% variation for several individual samples. Using individual T2 calibrations, the whole-brain oxygen extraction fraction and cerebral metabolic rate of oxygen of SCA participants were 0.38 ± 0.08 and 172 ± 42 µmol/min/100 g, respectively, which were comparable to those values measured on healthy volunteers. CONCLUSION Our results confirm that sickle blood T2 values not only depend on the hematocrit and oxygenation values, but also on other hematological factors. The individual T2 calibrations minimized the effect of heterogeneity of sickle blood between different SCA populations and improved the accuracy of T2 -based oximetry. The measured oxygen extraction fraction and cerebral metabolic rate of oxygen of this group of SCA participants were found to not differ significantly from those of healthy individuals.
Collapse
Affiliation(s)
- Wenbo Li
- Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - Xiang Xu
- Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - Peiying Liu
- Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - John J Strouse
- Department of Pediatrics, Division of Pediatric Hematology, Johns Hopkins University School of Medicine, Baltimore, Maryland.,Division of Hematology, Duke University, Durham, North Carolina
| | - James F Casella
- Department of Pediatrics, Division of Pediatric Hematology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Hanzhang Lu
- Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Peter C M van Zijl
- Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - Qin Qin
- Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| |
Collapse
|
36
|
Liu P, Parkinson C, Jiang D, Ouyang M, De Vis JB, Northington FJ, Tekes A, Huang H, Huisman TA, Golden WC. Characterization of MRI techniques to assess neonatal brain oxygenation and blood flow. NMR IN BIOMEDICINE 2019; 32:e4103. [PMID: 31038246 PMCID: PMC6581605 DOI: 10.1002/nbm.4103] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 02/22/2019] [Accepted: 03/12/2019] [Indexed: 06/09/2023]
Abstract
There is increasing interest in applying physiological MRI in neonates, based on the premise that physiological parameters may provide an early biomarker of neonatal brain health and injury. Two commonly used techniques are oxygen extraction fraction (OEF) measurement using T2 -relaxation-under-spin-tagging (TRUST) MRI and cerebral blood flow measurement using phase-contrast (PC) quantitative flow MRI, which collectively provide an assessment of the brain's oxygen consumption. However, prior research has only demonstrated proof of principle of these methods in neonates, without characterization or benchmarking of the techniques. This is because available time is limited in neonatal subjects, especially when scans are performed as add-ons to clinical scans (typically less than 5 min). The work presented aims to examine the TRUST and PC MRI sequences systematically in normal neonates, through research-dedicated scan sessions. A series of characterization and optimization studies were conducted in a total of 26 radiographically normal neonates on 3 T systems. Our results show that TRUST MRI at the superior sagittal sinus (SSS) provides an OEF measurement equivalent to that at the internal jugular vein (r = 0.80, n = 10), yet with shorter scan time. Lower resolution provided better precision in the TRUST measurement (p = 0.001, n = 9). Therefore, the preferred OEF measurement is to apply TRUST MRI at the SSS using a spatial resolution of 2.5 mm. For PC MRI, our results showed that non-gated PC MRI yielded blood flow measurements comparable to those from the more time-consuming gated approach in neonates (r = 0.89, n = 7). It was also found that blood flow could be overestimated by 18% when imaging resolution is larger than 0.3 mm (n = 7). Therefore, non-gated PC MRI with a spatial resolution of 0.3 mm is recommended for neonatal applications. In conclusion, this study verifies consistency of neonatal brain oxygenation and flow measurements across acquisition schemes and points to optimal strategies in parameter selection when using these sequences.
Collapse
Affiliation(s)
- Peiying Liu
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Charlamaine Parkinson
- Division of Neonatology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Dengrong Jiang
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Minhui Ouyang
- Radiology Research, Children’s Hospital of Philadelphia, Philadelphia, PA, United States
| | - Jill B. De Vis
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Frances J. Northington
- Division of Neonatology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Aylin Tekes
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Hao Huang
- Radiology Research, Children’s Hospital of Philadelphia, Philadelphia, PA, United States
| | - Thierry A.G.M. Huisman
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - W. Christopher Golden
- Division of Neonatology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| |
Collapse
|
37
|
Jiang D, Lu H, Parkinson C, Su P, Wei Z, Pan L, Tekes A, Huisman TAGM, Golden WC, Liu P. Vessel-specific quantification of neonatal cerebral venous oxygenation. Magn Reson Med 2019; 82:1129-1139. [PMID: 31066104 DOI: 10.1002/mrm.27788] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 03/25/2019] [Accepted: 04/08/2019] [Indexed: 12/11/2022]
Abstract
PURPOSE Noninvasive measurement of cerebral venous oxygenation (Yv ) in neonates is important in the assessment of brain oxygen extraction and consumption, and may be useful in characterizing brain development and neonatal brain diseases. This study aims to develop a rapid method for vessel-specific measurement of Yv in neonates. METHODS We developed a pulse sequence, named accelerated T2 -relaxation-under-phase-contrast (aTRUPC), which consists of velocity-encoding phase-contrast module to isolate pure blood signal, flow-insensitive T2 -preparation to quantify blood T2 , and turbo-field-echo (TFE) scheme for rapid image acquisition, which is critical for neonatal MRI. A series of studies were conducted. First, the pulse sequence was optimized in terms of TFE factor, velocity encoding (VENC), and slice thickness for best sensitivity. Second, to account for the influence of TFE acquisition on T2 quantification, simulation and experiments were conducted to establish the relationship between TFE-T2 and standard T2 . Finally, the complete aTRUPC sequence was applied on a group of healthy neonates and normative Yv values were determined. RESULTS Optimal parameters of aTRUPC in neonates were found to be a TFE factor of 15, VENC of 5 cm/s, and slice thickness of 10 mm. The TFE-T2 was on average 3.9% lower than standard T2 . These two measures were strongly correlated (R2 = 0.86); thus their difference can be accounted for by a correction equation, T2,standard = 1.2002 × T2,TFE - 10.6276. Neonatal Yv values in veins draining cortical brain and those draining central brain were 64.8 ± 2.9% and 70.2 ± 3.3%, respectively, with a significant difference (P =.02). CONCLUSION The aTRUPC MRI has the potential to provide vessel-specific quantification of cerebral Yv in neonates.
Collapse
Affiliation(s)
- Dengrong Jiang
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland.,Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Hanzhang Lu
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland.,Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, Maryland
| | - Charlamaine Parkinson
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, Maryland.,Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Pan Su
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Zhiliang Wei
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, Maryland
| | - Li Pan
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland.,Siemens Healthineers, Baltimore, Maryland
| | - Aylin Tekes
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland.,Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Thierry A G M Huisman
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland.,Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - W Christopher Golden
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, Maryland.,Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Peiying Liu
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
| |
Collapse
|
38
|
Jørgensen DS, Vejlstrup N, Rode L, Ekelund CK, Macgowan CK, Jensen LN, Nørgaard LN, Portnoy S, Seed M, Sundberg K, Søgaard K, Forman JL, Tabor A. Magnetic Resonance Imaging: A New Tool to Optimize the Prediction of Fetal Anemia? Fetal Diagn Ther 2019; 46:257-265. [PMID: 30731466 DOI: 10.1159/000494615] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 10/17/2018] [Indexed: 11/19/2022]
Abstract
INTRODUCTION The false-positive rate in the prediction of fetal anemia is 10-15%. We investigated if a new, noninvasive MRI method used as a supplement to ultrasound could improve the prediction. METHODS Fetuses suspected of anemia and controls were scanned in a 1.5-tesla MRI scanner 1-4 times during pregnancy. Cases were scanned before and after intrauterine blood transfusion with a T1-mapping MRI sequence in a cross-section of the umbilical vein. RESULTS Inclusion of 8 cases and 11 controls resulted in 10 case scans (2 cases were included twice) and 33 control scans. In controls, the T1 relaxation time was 1,005-1,391 ms; in cases with severe anemia, 1,505-1,595 ms, moderate anemia 1,503-1,525 ms, and no/mild anemia 1,245-1,410 ms. After blood transfusions, values dropped to 1,123-1,288 ms. The mean value in moderate and severe anemic cases was 275 ms higher than in controls (95% CI 210-341 ms, p < 0.0001), and after blood transfusion it was comparable to controls (3 ms, 95% CI -62 to 68 ms, p = 0.934). A 1,450-ms cut-off would have identified all cases in need of blood transfusion with no false-positive cases. CONCLUSIONS Our findings indicate a potential for this new MRI method to improve the prediction of fetal anemia as a supplement to ultrasound.
Collapse
Affiliation(s)
- Ditte S Jørgensen
- Center of Fetal Medicine, Department of Obstetrics, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark, .,Faculty of Medicine and Health Sciences, University of Copenhagen, Copenhagen, Denmark,
| | - Niels Vejlstrup
- Department of Cardiology, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Line Rode
- Department of Clinical Biochemistry, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Charlotte K Ekelund
- Center of Fetal Medicine, Department of Obstetrics, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Christopher K Macgowan
- Departments of Medical Biophysics and Medical Imaging, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - Lisa N Jensen
- Center of Fetal Medicine, Department of Obstetrics, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Lone Nikoline Nørgaard
- Center of Fetal Medicine, Department of Obstetrics, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Sharon Portnoy
- Departments of Medical Biophysics and Medical Imaging, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - Mike Seed
- Department of Diagnostic Imaging, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada.,Department of Pediatrics, Division of Paediatric Cardiology, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - Karin Sundberg
- Center of Fetal Medicine, Department of Obstetrics, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Kirsten Søgaard
- Center of Fetal Medicine, Department of Obstetrics, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Julie Lyng Forman
- Section of Biostatistics, Department of Public Health, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ann Tabor
- Center of Fetal Medicine, Department of Obstetrics, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.,Faculty of Medicine and Health Sciences, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
39
|
Precision of T1-relaxation time measurements in the hepatic portal vein: influence of measurement technique and sequence parameters. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2019; 32:359-368. [PMID: 30604145 DOI: 10.1007/s10334-018-00731-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 12/09/2018] [Accepted: 12/17/2018] [Indexed: 10/27/2022]
Abstract
OBJECTIVE To investigate the effects of a range of parameter settings on T1 measurement stability in the portal vein using the T1-mapping sequences Look-Locker (LL) and Modified Look-Locker inversion recovery (MOLLI). MATERIALS AND METHODS Ten different versions of LL and MOLLI sequences were tested and compared to a reference sequence provided by the MR manufacturer. Ten healthy volunteers were imaged multiple times on two separate scan days at 3T. The mean T1 values and coefficient of variation (CoV) were calculated for each of the ten sequences and compared to the reference sequence. RESULTS Six of the tested sequences had T1 values close to the reference sequence; among those, three sequences achieved lower CoV than the reference sequence. Lowest CoV was achieved using a non-triggered LL sequence with 5 beat readout and a 45o flip angle (mean T1 1733 ms ± 89 ms, CoV 1.3% ± 0.58%). CONCLUSION T1-measurements in the hepatic portal vein can be performed with high precision using either MOLLI or LL sequences provided that LL sampling duration is sufficiently long and flip angle sufficiently high. The advantage of constant timing outweighed the advantage of ECG-triggering.
Collapse
|
40
|
Morris EA, Juttukonda MR, Lee CA, Patel NJ, Pruthi S, Donahue MJ, Jordan LC. Elevated brain oxygen extraction fraction in preterm newborns with anemia measured using noninvasive MRI. J Perinatol 2018; 38:1636-1643. [PMID: 30254332 DOI: 10.1038/s41372-018-0229-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 08/09/2018] [Accepted: 08/21/2018] [Indexed: 01/15/2023]
Abstract
OBJECTIVE To test the hypothesis that cerebral oxygen extraction fraction (OEF) is elevated and inversely related to hematocrit level in anemic former very-low-birth-weight infants near term. STUDY DESIGN Prospective study of non-sedated preterm infants (post-menstrual age = 36 ± 2 weeks) over a range of hematocrits (0.23-0.49). Anatomical (T1-W, T2-W, and diffusion-weighted), cerebral blood flow (CBF), and OEF 3-T MRI were utilized. Statistical analysis included Spearman's rank-order correlation testing between study variables and intraclass correlation coefficients (ICC) calculated between consecutively acquired OEF scans. RESULTS Consecutive OEF measurements showed moderate-to-good agreement (ICC = 0.71; 95% CI = 0.40-0.87). OEF increased with worsening anemia (ρ = -0.58; p = 0.005), and OEF and basal ganglia CBF were positively correlated (ρ = 0.49; p = 0.023). CONCLUSION Noninvasive OEF MRI has moderate-to-good repeatability in non-sedated former preterm infants nearing term-equivalent age. Strong correlation of elevated OEF with anemia suggests hemodynamic compensation for anemia and could establish OEF as a useful biomarker of transfusion threshold for preterm infants.
Collapse
Affiliation(s)
- Emily A Morris
- Department of Pediatrics, Division of Neonatology, Vanderbilt University Medical Center, Nashville, TN, USA.
| | - Meher R Juttukonda
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Chelsea A Lee
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Niral J Patel
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Sumit Pruthi
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Manus J Donahue
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Psychiatry, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Physics and Astronomy, Vanderbilt University, Nashville, TN, USA
| | - Lori C Jordan
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| |
Collapse
|
41
|
Melbourne A, Aughwane R, Sokolska M, Owen D, Kendall G, Flouri D, Bainbridge A, Atkinson D, Deprest J, Vercauteren T, David A, Ourselin S. Separating fetal and maternal placenta circulations using multiparametric MRI. Magn Reson Med 2018; 81:350-361. [PMID: 30239036 PMCID: PMC6282748 DOI: 10.1002/mrm.27406] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 05/21/2018] [Accepted: 05/24/2018] [Indexed: 12/18/2022]
Abstract
PURPOSE The placenta is a vital organ for the exchange of oxygen, nutrients, and waste products between fetus and mother. The placenta may suffer from several pathologies, which affect this fetal-maternal exchange, thus the flow properties of the placenta are of interest in determining the course of pregnancy. In this work, we propose a new multiparametric model for placental tissue signal in MRI. METHODS We describe a method that separates fetal and maternal flow characteristics of the placenta using a 3-compartment model comprising fast and slowly circulating fluid pools, and a tissue pool is fitted to overlapping multiecho T2 relaxometry and diffusion MRI with low b-values. We implemented the combined model and acquisition on a standard 1.5 Tesla clinical system with acquisition taking less than 20 minutes. RESULTS We apply this combined acquisition in 6 control singleton placentas. Mean myometrial T2 relaxation time was 123.63 (±6.71) ms. Mean T2 relaxation time of maternal blood was 202.17 (±92.98) ms. In the placenta, mean T2 relaxation time of the fetal blood component was 144.89 (±54.42) ms. Mean ratio of maternal to fetal blood volume was 1.16 (±0.6), and mean fetal blood saturation was 72.93 (±20.11)% across all 6 cases. CONCLUSION The novel acquisition in this work allows the measurement of histologically relevant physical parameters, such as the relative proportions of vascular spaces. In the placenta, this may help us to better understand the physiological properties of the tissue in disease.
Collapse
Affiliation(s)
- Andrew Melbourne
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom.,School of Biomedical Engineering and Imaging, Kings College London, London, United Kingdom
| | - Rosalind Aughwane
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom.,Institute for Women's Health, University College Hospital,London, London, United Kingdom
| | | | - David Owen
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom.,School of Biomedical Engineering and Imaging, Kings College London, London, United Kingdom
| | - Giles Kendall
- Institute for Women's Health, University College Hospital,London, London, United Kingdom
| | - Dimitra Flouri
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom.,School of Biomedical Engineering and Imaging, Kings College London, London, United Kingdom
| | - Alan Bainbridge
- Medical Physics, University College Hospital, London, United Kingdom
| | - David Atkinson
- Centre for Medical Imaging, University College London, London, United Kingdom
| | - Jan Deprest
- Institute for Women's Health, University College Hospital,London, London, United Kingdom.,University Hospital KU Leuven, Leuven, Belgium
| | - Tom Vercauteren
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom.,School of Biomedical Engineering and Imaging, Kings College London, London, United Kingdom
| | - Anna David
- Institute for Women's Health, University College Hospital,London, London, United Kingdom.,University Hospital KU Leuven, Leuven, Belgium.,NIHR University College London Hospitals Biomedical Research Centre, London, United Kingdom
| | - Sebastien Ourselin
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom.,School of Biomedical Engineering and Imaging, Kings College London, London, United Kingdom
| |
Collapse
|
42
|
Qi Y, Liu P, Lin Z, Lu H, Wang X. Hemodynamic and Metabolic Assessment of Neonates With Punctate White Matter Lesions Using Phase-Contrast MRI and T2-Relaxation-Under-Spin-Tagging (TRUST) MRI. Front Physiol 2018; 9:233. [PMID: 29615927 PMCID: PMC5868490 DOI: 10.3389/fphys.2018.00233] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 03/01/2018] [Indexed: 11/23/2022] Open
Abstract
The brain's hemodynamic and metabolism of punctate white matter lesions (PWML) is poorly understood due to a scarcity of non-invasive imaging techniques. The aim of this study was to apply new MRI techniques to quantify cerebral metabolic rate of oxygen (CMRO2), global cerebral blood flow (CBF), oxygen saturation fractions in venous blood (Yv) and oxygen extraction fraction (OEF) in neonates with PWML, for better understanding of the pathophysiology of PWML. Fifty-one newborns were recruited continuously, including 23 neonatal patients with PWML and 28 normal control neonates. Phase-contrast (PC) MRI and T2-Relaxation-Under-Spin-Tagging (TRUST) MRI were performed for the measurement of CBF and Yv. OEF and CMRO2 were calculated from the CBF and Yv values. The total maturation score (TMS) was assessed for each neonate on standard T1, 2-weighted images to evaluate cerebral maturation. The CMRO2, CBF, Yv, and OEF values were compared between groups, and their associations with age and TMS were evaluated. Significant differences between PWML group and control group were found in CMRO2 (P = 0.020), CBF (P = 0.027), Yv (P = 0.012), OEF (P = 0.018). After age/maturation is accounted for, Yv and OEF showed significant dependence on the groups (P < 0.05). Newborns with PWML had lower OEF and higher Yv. CMRO2, CBF and brain volume were correlated with age (P < 0.001) and TMS (P < 0.05). It is feasible to use non-invasive MRI methods to measure cerebral oxygen supply and consumption in neonates with PWML. Newborns with PWML have lower oxygen consumption. Yv and OEF may be helpful for the diagnosis of PWML. The positive correlation between CBF and TMS, and between CMRO2 and TMS suggested that as myelination progresses, the blood supply and oxygen metabolism in the brain increase to meet the escalating energy demand.
Collapse
Affiliation(s)
- Ying Qi
- Department of Radiology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Peiying Liu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Zixuan Lin
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Hanzhang Lu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Xiaoming Wang
- Department of Radiology, Shengjing Hospital of China Medical University, Shenyang, China
| |
Collapse
|
43
|
Zun Z, Limperopoulos C. Placental perfusion imaging using velocity-selective arterial spin labeling. Magn Reson Med 2018; 80:1036-1047. [PMID: 29436733 DOI: 10.1002/mrm.27100] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 12/30/2017] [Accepted: 01/02/2018] [Indexed: 11/10/2022]
Affiliation(s)
- Zungho Zun
- Division of Diagnostic Imaging and Radiology, Children's National Medical Center, Washington, DC.,Division of Fetal and Transitional Medicine, Children's National Medical Center, Washington, DC.,Department of Pediatrics, School of Medicine and Health Sciences, George Washington University, Washington, DC.,Department of Radiology, School of Medicine and Health Sciences, George Washington University, Washington, DC
| | - Catherine Limperopoulos
- Division of Diagnostic Imaging and Radiology, Children's National Medical Center, Washington, DC.,Division of Fetal and Transitional Medicine, Children's National Medical Center, Washington, DC.,Department of Pediatrics, School of Medicine and Health Sciences, George Washington University, Washington, DC.,Department of Radiology, School of Medicine and Health Sciences, George Washington University, Washington, DC
| |
Collapse
|
44
|
Jiang D, Liu P, Li Y, Mao D, Xu C, Lu H. Cross-vendor harmonization of T 2 -relaxation-under-spin-tagging (TRUST) MRI for the assessment of cerebral venous oxygenation. Magn Reson Med 2018; 80:1125-1131. [PMID: 29369415 DOI: 10.1002/mrm.27080] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 11/22/2017] [Accepted: 12/18/2017] [Indexed: 12/28/2022]
Affiliation(s)
- Dengrong Jiang
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Peiying Liu
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Yang Li
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Graduate School of Biomedical Sciences, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Deng Mao
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Graduate School of Biomedical Sciences, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Cuimei Xu
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Hanzhang Lu
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, Maryland, USA
| |
Collapse
|
45
|
Stout JN, Tisdall MD, McDaniel P, Gagoski B, Bolar DS, Grant PE, Adalsteinsson E. Assessing the effects of subject motion on T 2 relaxation under spin tagging (TRUST) cerebral oxygenation measurements using volume navigators. Magn Reson Med 2017; 78:2283-2289. [PMID: 28247427 PMCID: PMC5573669 DOI: 10.1002/mrm.26616] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 12/02/2016] [Accepted: 12/28/2016] [Indexed: 12/16/2022]
Abstract
PURPOSE Subject motion may cause errors in estimates of blood T2 when using the T2 -relaxation under spin tagging (TRUST) technique on noncompliant subjects like neonates. By incorporating 3D volume navigators (vNavs) into the TRUST pulse sequence, independent measurements of motion during scanning permit evaluation of these errors. METHODS The effects of integrated vNavs on TRUST-based T2 estimates were evaluated using simulations and in vivo subject data. Two subjects were scanned with the TRUST+vNav sequence during prescribed movements. Mean motion scores were derived from vNavs and TRUST images, along with a metric of exponential fit quality. Regression analysis was performed between T2 estimates and mean motion scores. Also, motion scores were determined from independent neonatal scans. RESULTS vNavs negligibly affected venous blood T2 estimates and better detected subject motion than fit quality metrics. Regression analysis showed that T2 is biased upward by 4.1 ms per 1 mm of mean motion score. During neonatal scans, mean motion scores of 0.6 to 2.0 mm were detected. CONCLUSION Motion during TRUST causes an overestimate of T2 , which suggests a cautious approach when comparing TRUST-based cerebral oxygenation measurements of noncompliant subjects. Magn Reson Med 78:2283-2289, 2017. © 2017 International Society for Magnetic Resonance in Medicine.
Collapse
Affiliation(s)
- Jeffrey N. Stout
- Harvard-MIT Health Sciences and Technology, Institute for Medical
Engineering & Science, MIT, Cambridge, MA, United States
| | - M. Dylan Tisdall
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts
General Hospital, Charlestown, MA, United States
- Radiology, Harvard Medical School, Boston, MA, United States
| | - Patrick McDaniel
- Department of Electrical Engineering and Computer Science, MIT,
Cambridge, MA, United States
| | - Borjan Gagoski
- Department of Radiology, Boston Children’s Hospital, Boston
MA, United States
| | - Divya S. Bolar
- Department of Radiology, Massachusetts General Hospital, Boston, MA,
United States
| | - Patricia Ellen Grant
- Department of Radiology, Boston Children’s Hospital, Boston
MA, United States
- Department of Pediatrics, Boston Children’s Hospital, Boston
MA, United States
| | - Elfar Adalsteinsson
- Harvard-MIT Health Sciences and Technology, Institute for Medical
Engineering & Science, MIT, Cambridge, MA, United States
- Department of Electrical Engineering and Computer Science, MIT,
Cambridge, MA, United States
| |
Collapse
|
46
|
Varghese J, Potter LC, LaFountain R, Pan X, Raman SV, Ahmad R, Simonetti OP. CMR-based blood oximetry via multi-parametric estimation using multiple T2 measurements. J Cardiovasc Magn Reson 2017; 19:88. [PMID: 29121971 PMCID: PMC5680788 DOI: 10.1186/s12968-017-0403-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Accepted: 10/18/2017] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Measurement of blood oxygen saturation (O2 saturation) is of great importance for evaluation of patients with many cardiovascular diseases, but currently there are no established non-invasive methods to measure blood O2 saturation in the heart. While T2-based CMR oximetry methods have been previously described, these approaches rely on technique-specific calibration factors that may not generalize across patient populations and are impractical to obtain in individual patients. We present a solution that utilizes multiple T2 measurements made using different inter-echo pulse spacings. These data are jointly processed to estimate all unknown parameters, including O2 saturation, in the Luz-Meiboom (L-M) model. We evaluated the accuracy of the proposed method against invasive catheterization in a porcine hypoxemia model. METHODS Sufficient data diversity to estimate the various unknown parameters of the L-M model, including O2 saturation, was achieved by acquiring four T2 maps, each at a different τ 180 (12, 15, 20, and 25 ms). Venous and arterial blood T2 values from these maps, together with hematocrit and arterial O2 saturation, were jointly processed to derive estimates for venous O2 saturation and other nuisance parameters in the L-M model. The technique was validated by a progressive graded hypoxemia experiment in seven pigs. CMR estimates of O2 saturation in the right ventricle were compared against a reference O2 saturation obtained by invasive catheterization from the right atrium in each pig, at each hypoxemia stage. O2 saturation derived from the proposed technique was also compared against the previously described method of applying a global calibration factor (K) to the simplified L-M model. RESULTS Venous O2 saturation results obtained using the proposed CMR oximetry method exhibited better agreement (y = 0.84× + 12.29, R2 = 0.89) with invasive blood gas analysis when compared to O2 saturation estimated by a global calibration method (y = 0.69× + 27.52, R2 = 0.73). CONCLUSIONS We have demonstrated a novel, non-invasive method to estimate O2 saturation using quantitative T2 mapping. This technique may provide a valuable addition to the diagnostic utility of CMR in patients with congenital heart disease, heart failure, and pulmonary hypertension.
Collapse
Affiliation(s)
- Juliet Varghese
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH USA
| | - Lee C. Potter
- Department of Electrical and Computer Engineering, The Ohio State University, Columbus, OH USA
| | - Richard LaFountain
- Department of Health and Exercise Science, The Ohio State University, Columbus, OH USA
| | - Xueliang Pan
- Center for Biostatistics, The Ohio State University, Columbus, OH USA
| | - Subha V. Raman
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH USA
- Division of Cardiovascular Medicine, Department of Internal Medicine, The Ohio State University Wexner Medical Center, Columbus, OH USA
- Department of Radiology, The Ohio State University Wexner Medical Center, Columbus, OH USA
| | - Rizwan Ahmad
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH USA
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH USA
| | - Orlando P. Simonetti
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH USA
- Division of Cardiovascular Medicine, Department of Internal Medicine, The Ohio State University Wexner Medical Center, Columbus, OH USA
- Department of Radiology, The Ohio State University Wexner Medical Center, Columbus, OH USA
| |
Collapse
|
47
|
Portnoy S, Milligan N, Seed M, Sled JG, Macgowan CK. Human umbilical cord blood relaxation times and susceptibility at 3 T. Magn Reson Med 2017; 79:3194-3206. [DOI: 10.1002/mrm.26978] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 09/01/2017] [Accepted: 09/27/2017] [Indexed: 12/30/2022]
Affiliation(s)
- Sharon Portnoy
- Department of Medical Biophysics; University of Toronto; Toronto Ontario Canada
- Mouse Imaging Centre; Hospital for Sick Children; Toronto Ontario Canada
| | - Natasha Milligan
- Department of Obstetrics & Gynecology; Mount Sinai Hospital; Toronto Ontario Canada
| | - Mike Seed
- Division of Cardiology; Hospital for Sick Children; Toronto Ontario Canada
- Department of Pediatrics and Diagnostic Imaging; University of Toronto; Toronto Ontario Canada
| | - John G. Sled
- Department of Medical Biophysics; University of Toronto; Toronto Ontario Canada
- Mouse Imaging Centre; Hospital for Sick Children; Toronto Ontario Canada
- Department of Obstetrics and Gynecology; University of Toronto; Toronto Ontario Canada
| | - Christopher K. Macgowan
- Department of Medical Biophysics; University of Toronto; Toronto Ontario Canada
- Division of Translational Medicine; Hospital for Sick Children; Toronto Ontario Canada
- Labatt Family Heart Centre; Hospital for Sick Children; Toronto Ontario Canada
| |
Collapse
|
48
|
Li W, Liu P, Lu H, Strouse JJ, van Zijl PC, Qin Q. Fast measurement of blood T 1 in the human carotid artery at 3T: Accuracy, precision, and reproducibility. Magn Reson Med 2017; 77:2296-2302. [PMID: 27436420 PMCID: PMC5250597 DOI: 10.1002/mrm.26325] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 05/16/2016] [Accepted: 06/07/2016] [Indexed: 11/10/2022]
Abstract
PURPOSE To develop a fast protocol for measuring T1 values in the internal carotid artery (ICA), to validate this technique with in vitro measurements, and to evaluate its reproducibility. METHODS A modified Look-Locker sequence was optimized to enable rapid determination of T1 in the ICA at 3T. T1 values from the ICA were compared with in vitro measurements on individually sampled venous blood oxygenated to arterial levels. A test-retest reproducibility study was also conducted. RESULTS The group-averaged arterial blood T1 value was 1908 ± 77 ms for six women (hematocrit = 0.39 ± 0.03) and 1785 ± 55 ms for seven men (hematocrit = 0.45 ± 0.02), which is 100-200 ms longer than the widely adopted value obtained from bovine blood experiments. The arterial T1 value per subject correlated significantly with individual hematocrit values. The intrasession and intersession coefficients of variation were 1.1% and 2.1%, respectively, indicating good precision and reproducibility of our method. Reasonable agreement was observed between the in vivo and in vitro results with a correlation coefficient of 0.78. CONCLUSION The proposed method can provide fast arterial T1 measurement on individual subjects. When not performing such a subject-specific measurement, we recommend the use of 1908 ms and 1785 ms for healthy women and men, respectively, or 1841 ms for adults in general. Magn Reson Med 77:2296-2302, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
Collapse
Affiliation(s)
- Wenbo Li
- Department of Radiology; Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
| | - Peiying Liu
- Department of Radiology; Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Hanzhang Lu
- Department of Radiology; Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - John J. Strouse
- Division of Pediatric Hematology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Peter C.M. van Zijl
- Department of Radiology; Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
| | - Qin Qin
- Department of Radiology; Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
| |
Collapse
|
49
|
Alderliesten T, De Vis JB, Lemmers PMA, Hendrikse J, Groenendaal F, van Bel F, Benders MJNL, Petersen ET. Brain oxygen saturation assessment in neonates using T 2-prepared blood imaging of oxygen saturation and near-infrared spectroscopy. J Cereb Blood Flow Metab 2017; 37:902-913. [PMID: 27151900 PMCID: PMC5363470 DOI: 10.1177/0271678x16647737] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Although near-infrared spectroscopy is increasingly being used to monitor cerebral oxygenation in neonates, it has a limited penetration depth. The T2-prepared Blood Imaging of Oxygen Saturation (T2-BIOS) magnetic resonance sequence provides an oxygen saturation estimate on a voxel-by-voxel basis, without needing a respiratory calibration experiment. In 15 neonates, oxygen saturation measured by T2-prepared blood imaging of oxygen saturation and near-infrared spectroscopy were compared. In addition, these measures were compared to cerebral blood flow and venous oxygen saturation in the sagittal sinus. A strong linear relation was found between the oxygen saturation measured by magnetic resonance imaging and the oxygen saturation measured by near-infrared spectroscopy ( R2 = 0.64, p < 0.001). Strong linear correlations were found between near-infrared spectroscopy oxygen saturation, and magnetic resonance imaging measures of frontal cerebral blood flow, whole brain cerebral blood flow and venous oxygen saturation in the sagittal sinus ( R2 = 0.71, 0.50, 0.65; p < 0.01). The oxygen saturation obtained by T2-prepared blood imaging of oxygen saturation correlated with venous oxygen saturation in the sagittal sinus ( R2 = 0.49, p = 0.023), but no significant correlations could be demonstrated with frontal and whole brain cerebral blood flow. These results suggest that measuring oxygen saturation by T2-prepared blood imaging of oxygen saturation is feasible, even in neonates. Strong correlations between the various methods work as a cross validation for near-infrared spectroscopy and T2-prepared blood imaging of oxygen saturation, confirming the validity of using of these techniques for determining cerebral oxygenation.
Collapse
Affiliation(s)
- Thomas Alderliesten
- Department of Neonatology, Wilhelmina Children’s Hospital, University Medical Center Utrecht, Utrecht, The Netherlands
- Thomas Alderliesten, Department of Neonatology, Wilhelmina Children’s Hospital, University Medical Center Utrecht, Room KE04.123.1, PO Box 85090, 3584 AE Ut, The Netherlands.
| | - Jill B De Vis
- Department of Neonatology, Wilhelmina Children’s Hospital, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Petra MA Lemmers
- Department of Neonatology, Wilhelmina Children’s Hospital, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Jeroen Hendrikse
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Floris Groenendaal
- Department of Neonatology, Wilhelmina Children’s Hospital, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Frank van Bel
- Department of Neonatology, Wilhelmina Children’s Hospital, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Manon JNL Benders
- Department of Neonatology, Wilhelmina Children’s Hospital, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Esben T Petersen
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
| |
Collapse
|
50
|
Portnoy S, Seed M, Sled JG, Macgowan CK. Non-invasive evaluation of blood oxygen saturation and hematocrit from T 1 and T 2 relaxation times: In-vitro validation in fetal blood. Magn Reson Med 2017; 78:2352-2359. [PMID: 28191646 DOI: 10.1002/mrm.26599] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 11/17/2016] [Accepted: 12/13/2016] [Indexed: 01/24/2023]
Abstract
PURPOSE We propose an analytical method for calculating blood hematocrit (Hct) and oxygen saturation (sO2 ) from measurements of its T1 and T2 relaxation times. THEORY Through algebraic substitution, established two-compartment relationships describing R1=T1-1 and R2=T2-1 as a function of hematocrit and oxygen saturation were rearranged to solve for Hct and sO2 in terms of R1 and R2 . Resulting solutions for Hct and sO2 are the roots of cubic polynomials. METHODS Feasibility of the method was established by comparison of Hct and sO2 estimates obtained from relaxometry measurements (at 1.5 Tesla) in cord blood specimens to ground-truth values obtained by blood gas analysis. Monte Carlo simulations were also conducted to assess the effect of T1 , T2 measurement uncertainty on precision of Hct and sO2 estimates. RESULTS Good agreement was observed between estimated and ground-truth blood properties (bias = 0.01; 95% limits of agreement = ±0.13 for Hct and sO2 ). Considering the combined effects of biological variability and random measurement noise, we estimate a typical uncertainty of ±0.1 for Hct, sO2 estimates. CONCLUSION Results demonstrate accurate quantification of Hct and sO2 from T1 and T2 . This method is applicable to noninvasive fetal vessel oximetry-an application where existing oximetry devices are unusable or require risky blood-sampling procedures. Magn Reson Med 78:2352-2359, 2017. © 2017 International Society for Magnetic Resonance in Medicine.
Collapse
Affiliation(s)
- Sharon Portnoy
- University of Toronto, Department of Medical Biophysics, Toronto, Canada.,Mouse Imaging Centre, Hospital for Sick Children, Toronto, Canada
| | - Mike Seed
- Hospital for Sick Children, Division of Cardiology, Toronto, Canada.,University of Toronto, Department of Pediatrics and Diagnostic Imaging, Toronto, Canada
| | - John G Sled
- University of Toronto, Department of Medical Biophysics, Toronto, Canada.,Mouse Imaging Centre, Hospital for Sick Children, Toronto, Canada.,University of Toronto, Department of Obstetrics and Gynecology, Toronto, Canada
| | - Christopher K Macgowan
- University of Toronto, Department of Medical Biophysics, Toronto, Canada.,Hospital for Sick Children, Department of Physiology and Experimental Medicine, Toronto, Canada
| |
Collapse
|