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Rane Levendovszky S, Flores J, Peskind ER, Václavů L, van Osch MJ, Iliff J. Preliminary investigations into human neurofluid transport using multiple novel non-contrast MRI methods. J Cereb Blood Flow Metab 2024:271678X241264407. [PMID: 39053490 DOI: 10.1177/0271678x241264407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 07/27/2024]
Abstract
We discuss two potential non-invasive MRI methods to study phenomena related to subarachnoid cerebrospinal fluid (CSF) motion and perivascular fluid transport, and their association with sleep and aging. We apply diffusion-based intravoxel incoherent motion (IVIM) imaging to evaluate pseudodiffusion coefficient, D*, or CSF movement across large spaces like the subarachnoid space (SAS). We also performed perfusion-based multi-echo, Hadamard encoded arterial spin labeling (ASL) to evaluate whole brain cortical cerebral blood flow (CBF) and trans-endothelial exchange (Tex) of water from the vasculature into the perivascular space and parenchyma. Both methods were used in young adults (N = 9, 6 F, 23 ± 3 years old) in the setting of sleep and sleep deprivation. To study aging, 10 older adults (6 F, 67 ± 3 years old) were imaged after a night of normal sleep and compared with the young adults. D* in SAS was significantly (p < 0.05) reduced with sleep deprivation (0.016 ± 0.001 mm2/s) compared to normal sleep (0.018 ± 0.001 mm2/s) and marginally reduced with aging (0.017 ± 0.001 mm2/s, p = 0.029). Cortical CBF and Tex were unchanged with sleep deprivation but significantly lower in older adults (37 ± 3 ml/100 g/min, 578 ± 61 ms) than in young adults (42 ± 2 ml/100 g/min, 696 ± 62 ms). IVIM was sensitive to sleep physiology and aging, and multi-echo, multi-delay ASL was sensitive to aging.
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Affiliation(s)
| | - Jaqueline Flores
- Department of Radiology, University of Washington School of Medicine, Seattle, WA, USA
| | - Elaine R Peskind
- VISN 20 Mental Illness Research, Education, and Clinical Center, Veterans Affairs Puget Sound Healthcare System, Seattle, WA, USA
| | - Lena Václavů
- C.J. Gorter MRI Center, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Matthias Jp van Osch
- C.J. Gorter MRI Center, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Jeffrey Iliff
- VISN 20 Mental Illness Research, Education, and Clinical Center, Veterans Affairs Puget Sound Healthcare System, Seattle, WA, USA
- Department of Psychiatry and Behavioral Science, University of Washington School of Medicine, Seattle, WA, USA
- Department of Neurology, University of Washington School of Medicine, Seattle, WA, USA
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2
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Shao X, Shou Q, Felix K, Ojogho B, Jiang X, Gold BT, Herting MM, Goldwaser EL, Kochunov P, Hong LE, Pappas I, Braskie M, Kim H, Cen S, Jann K, Wang DJJ. Age-Related Decline in Blood-Brain Barrier Function is More Pronounced in Males than Females in Parietal and Temporal Regions. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.12.575463. [PMID: 38293052 PMCID: PMC10827081 DOI: 10.1101/2024.01.12.575463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
The blood-brain barrier (BBB) plays a pivotal role in protecting the central nervous system (CNS), shielding it from potential harmful entities. A natural decline of BBB function with aging has been reported in both animal and human studies, which may contribute to cognitive decline and neurodegenerative disorders. Limited data also suggest that being female may be associated with protective effects on BBB function. Here we investigated age and sex-dependent trajectories of perfusion and BBB water exchange rate (kw) across the lifespan in 186 cognitively normal participants spanning the ages of 8 to 92 years old, using a non-invasive diffusion prepared pseudo-continuous arterial spin labeling (DP-pCASL) MRI technique. We found that the pattern of BBB kw decline with aging varies across brain regions. Moreover, results from our DP-pCASL technique revealed a remarkable decline in BBB kw beginning in the early 60s, which was more pronounced in males. In addition, we observed sex differences in parietal and temporal regions. Our findings provide in vivo results demonstrating sex differences in the decline of BBB function with aging, which may serve as a foundation for future investigations into perfusion and BBB function in neurodegenerative and other brain disorders.
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Affiliation(s)
- Xingfeng Shao
- USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California
| | - Qinyang Shou
- USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California
| | - Kimberly Felix
- Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California
| | - Brandon Ojogho
- USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California
| | - Xuejuan Jiang
- Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California
- Department of Ophthalmology, Keck School of Medicine, University of Southern California
| | - Brian T. Gold
- Department of Neuroscience, College of Medicine, University of Kentucky
| | - Megan M Herting
- Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California
| | - Eric L Goldwaser
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine
- Interventional Psychiatry Program, Department of Psychiatry, Weill Cornell Medicine
| | - Peter Kochunov
- Louis A. Faillace Department of Psychiatry and Behavioral Sciences at McGovern Medical School, The University of Texas Health Science Center at Houston
| | - L. Elliot Hong
- Louis A. Faillace Department of Psychiatry and Behavioral Sciences at McGovern Medical School, The University of Texas Health Science Center at Houston
| | - Ioannis Pappas
- USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California
| | - Meredith Braskie
- USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California
| | - Hosung Kim
- USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California
| | - Steven Cen
- Department of Radiology and Neurology, Keck School of Medicine, University of Southern California
| | - Kay Jann
- USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California
| | - Danny JJ Wang
- USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California
- Department of Radiology and Neurology, Keck School of Medicine, University of Southern California
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Mouchtouris N, Ailes I, Chang K, Flanders A, Mohamed F, Tjoumakaris S, Gooch R, Jabbour P, Rosenwasser R, Alizadeh M. The impact of mechanical thrombectomy on the blood-brain barrier in patients with acute ischemic stroke: A non-contrast MR imaging study using DP-pCASL and NODDI. Neuroimage Clin 2024; 43:103629. [PMID: 38865844 DOI: 10.1016/j.nicl.2024.103629] [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: 04/18/2024] [Revised: 05/23/2024] [Accepted: 06/04/2024] [Indexed: 06/14/2024]
Abstract
BACKGROUND AND PURPOSE While mechanical thrombectomy (MT) achieves restoration of cerebral blood flow to the area at risk in patients with acute ischemic stroke (AIS), the influx of blood flow may exacerbate the blood-brain barrier (BBB) disruption and extravasation across the BBB, and it therefore remains unclear how reperfusion impacts the blood-brain barrier integrity. In this study, we use diffusion-prepared pseudocontinuous ASL (DP-pCASL) and Neurite Orientation Dispersion and Density Imaging (NODDI) sequence to measure the water exchange rate (kw) in patients who underwent either MT or medical management and determine its impact on the brain tissue microstructure in order to elucidate the impact of MT on BBB complex integrity. MATERIALS AND METHODS We prospectively enrolled 21 patients with AIS treated at our institution from 10/2021 to 6/2023 who underwent MR imaging at a 3.0-Tesla scanner. Patients underwent DP-pCASl and NODDI imaging in addition to the standard stroke protocol which generated cerebral blood flow (CBF), arterial transit time (ATT), water exchange rate (kw), orientation dispersion index (ODI), intracellular volume fraction (ICVF), and free water fraction (FWF) parametric maps. RESULTS Of the 21 patients, 11 underwent MT and 10 were treated non-operatively. The average age and NIHSS for the MT cohort and non-MT cohorts were 69.3 ± 16.6 years old and 15.0 (12.0-20.0), and 70.2 ± 10.7 (p = 0.882) and 6.0 (3.8-9.0, p = 0.003) respectively. The average CBF, ATT, and kw in the infarcted territory of the MT cohort were 38.2 (18.4-59.6), 1347.6 (1182.5-1842.3), and 107.8 (79.2-140.1) respectively. The average CBF, ATT, and kw in the stroke ROI were 16.0 (8.8-36.6, p = 0.036), 1090.8 (937.1-1258.9, p = 0.013), 89.7 (68.0-122.7, p = 0.314) respectively. Linear regression analysis showed increasing CBF (p = 0.008) and undergoing mechanical thrombectomy (p = 0.048) were significant predictors of increased kw. CONCLUSION Using our multimodal non-contrast MRI protocol, we demonstrate that increased CBF and mechanical thrombectomy increased kw, suggesting a better functioning BBB complex. Higher kw suggests less disruption of the BBB complex in the MT cohort.
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Affiliation(s)
- Nikolaos Mouchtouris
- Department of Neurological Surgery, Thomas Jefferson University Hospital, Philadelphia, PA, United States.
| | - Isaiah Ailes
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, United States
| | - Ki Chang
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, United States
| | - Adam Flanders
- Department of Radiology, Thomas Jefferson University Hospital, Philadelphia, PA, United States
| | - Feroze Mohamed
- Department of Radiology, Thomas Jefferson University Hospital, Philadelphia, PA, United States
| | - Stavropoula Tjoumakaris
- Department of Neurological Surgery, Thomas Jefferson University Hospital, Philadelphia, PA, United States
| | - Reid Gooch
- Department of Neurological Surgery, Thomas Jefferson University Hospital, Philadelphia, PA, United States
| | - Pascal Jabbour
- Department of Neurological Surgery, Thomas Jefferson University Hospital, Philadelphia, PA, United States
| | - Robert Rosenwasser
- Department of Neurological Surgery, Thomas Jefferson University Hospital, Philadelphia, PA, United States
| | - Mahdi Alizadeh
- Department of Neurological Surgery, Thomas Jefferson University Hospital, Philadelphia, PA, United States
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Mouchtouris N, Ailes I, Gooch R, Raimondo C, Oghli YS, Tjoumakaris S, Jabbour P, Rosenwasser R, Alizadeh M. Quantifying blood-brain barrier permeability in patients with ischemic stroke using non-contrast MRI. Magn Reson Imaging 2024; 109:165-172. [PMID: 38513785 DOI: 10.1016/j.mri.2024.03.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 03/17/2024] [Accepted: 03/18/2024] [Indexed: 03/23/2024]
Abstract
Increased blood-brain barrier permeability (BBBP) after ischemic stroke predisposes patients to hemorrhagic conversion. While altered BBBP can impact patient recovery, it is not routinely assessed during the workup of acute ischemic stroke (AIS). We study the effectiveness of the non-contrast MRI sequences diffusion-prepared pseudocontinuous arterial spin labeling (DP-pCASL) and Neurite Orientation Dispersion and Density Imaging (NODDI) in assessing BBBP and correlating to tissue microstructure after ischemic insult. Twelve patients with AIS were prospectively enrolled to undergo our multimodal MR imaging, which generated the DP-pCASL-derived cerebral blood flow (CBF), arterial transit time (ATT), and water exchange rate (kw) and the NODDI-derived b0, mean diffusivity (MD), orientation dispersion index (ODI), intracellular volume fraction (ICVF), and isotropic volume fraction (ISO) parametric maps. The mean age of the patients was 70.2 ± 14.8 with an average NIHSS of 13.0 (7.3-19.8). MR imaging was performed on average at 53.7 (27.8-93.3) hours from stroke symptom onset. The water exchange rate (kw) of the infarcted area and its contralateral territory were 89.7 min-1 (66.7-121.9) and 89.9 min-1 (65.9-106.0) respectively (p = 0.887). Multivariable linear regression analysis showed that b0, ODI, ISO and mechanical thrombectomy were significant predictors of kw. DP-pCASL and NODDI are promising non-contrast sequences for the routine assessment of BBBP.
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Affiliation(s)
- Nikolaos Mouchtouris
- Department of Neurological Surgery, Thomas Jefferson University Hospital, Philadelphia, PA, United States.
| | - Isaiah Ailes
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, United States
| | - Reid Gooch
- Department of Neurological Surgery, Thomas Jefferson University Hospital, Philadelphia, PA, United States
| | - Christian Raimondo
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, United States
| | - Yazan Shamli Oghli
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, United States
| | - Stavropoula Tjoumakaris
- Department of Neurological Surgery, Thomas Jefferson University Hospital, Philadelphia, PA, United States
| | - Pascal Jabbour
- Department of Neurological Surgery, Thomas Jefferson University Hospital, Philadelphia, PA, United States
| | - Robert Rosenwasser
- Department of Neurological Surgery, Thomas Jefferson University Hospital, Philadelphia, PA, United States
| | - Mahdi Alizadeh
- Department of Neurological Surgery, Thomas Jefferson University Hospital, Philadelphia, PA, United States
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Mahroo A, Konstandin S, Günther M. Blood-Brain Barrier Permeability to Water Measured Using Multiple Echo Time Arterial Spin Labeling MRI in the Aging Human Brain. J Magn Reson Imaging 2024; 59:1269-1282. [PMID: 37337979 DOI: 10.1002/jmri.28874] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 06/06/2023] [Accepted: 06/06/2023] [Indexed: 06/21/2023] Open
Abstract
BACKGROUND The blood-brain barrier (BBB) plays a vital role in maintaining brain homeostasis, but the integrity of this barrier deteriorates slowly with aging. Noninvasive water exchange magnetic resonance imaging (MRI) methods may identify changes in the BBB occurring with healthy aging. PURPOSE To investigate age-related changes in the BBB permeability to water using multiple-echo-time (multi-TE) arterial spin labeling (ASL) MRI. STUDY TYPE Prospective, cohort. POPULATION Two groups of healthy humans-older group (≥50 years, mean age = 56 ± 4 years, N = 13, females = 5) and younger group (≤20 years, mean age = 18 ± 1, N = 13, females = 7). FIELD STRENGTH/SEQUENCE A 3T, multi-TE Hadamard pCASL with 3D Gradient and Spin Echo (GRASE) readout. ASSESSMENT Two different approaches of variable complexity were applied. A physiologically informed biophysical model with a higher complexity estimating time ( T ex ) taken by the labeled water to move across the BBB and a simpler model of triexponential decay measuring tissue transition rate ( k lin ) . STATISTICS Two-tailed unpaired Student t-test, Pearson's correlation coefficient and effect size. P < 0.05 was considered significant. RESULTS Older volunteers showed significant differences of 36% lower T ex , 29% lower cerebral perfusion, 17% pronged arterial transit time and 22% shorter intra-voxel transit time compared to the younger volunteers. Tissue fraction ( f EV ) at the earliest TI = 1600 msec was significantly higher in the older group, which contributed to a significantly lower k lin compared to the younger group. f EV at TI = 1600 msec showed significant negative correlation with T ex (r = -0.80), and k lin and T ex showed significant positive correlation (r = 0.73). DATA CONCLUSIONS Both approaches of Multi-TE ASL imaging showed sensitivity to detect age-related changes in the BBB permeability. High tissue fractions at the earliest TI and short T ex in the older volunteers indicate that the BBB permeability increased with age. EVIDENCE LEVEL 2 TECHNICAL EFFICACY: Stage 1.
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Affiliation(s)
- Amnah Mahroo
- Imaging Physics, Fraunhofer Institute for Digital Medicine MEVIS, Bremen, Germany
| | - Simon Konstandin
- Imaging Physics, Fraunhofer Institute for Digital Medicine MEVIS, Bremen, Germany
- mediri GmbH, Heidelberg, Germany
| | - Matthias Günther
- Imaging Physics, Fraunhofer Institute for Digital Medicine MEVIS, Bremen, Germany
- mediri GmbH, Heidelberg, Germany
- MR-Imaging and Spectroscopy, University of Bremen, Bremen, Germany
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6
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Voorter PHM, van Dinther M, Jansen WJ, Postma AA, Staals J, Jansen JFA, van Oostenbrugge RJ, van der Thiel MM, Backes WH. Blood-Brain Barrier Disruption and Perivascular Spaces in Small Vessel Disease and Neurodegenerative Diseases: A Review on MRI Methods and Insights. J Magn Reson Imaging 2024; 59:397-411. [PMID: 37658640 DOI: 10.1002/jmri.28989] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 08/17/2023] [Accepted: 08/17/2023] [Indexed: 09/03/2023] Open
Abstract
Perivascular spaces (PVS) and blood-brain barrier (BBB) disruption are two key features of cerebral small vessel disease (cSVD) and neurodegenerative diseases that have been linked to cognitive impairment and are involved in the cerebral waste clearance system. Magnetic resonance imaging (MRI) offers the possibility to study these pathophysiological processes noninvasively in vivo. This educational review provides an overview of the MRI techniques used to assess PVS functionality and BBB disruption. MRI-visible PVS can be scored on structural images by either (subjectively) counting or (automatically) delineating the PVS. We highlight emerging (diffusion) techniques to measure proxies of perivascular fluid and its movement, which may provide a more comprehensive understanding of the role of PVS in diseases. For the measurement of BBB disruption, we explain the most commonly used MRI technique, dynamic contrast-enhanced (DCE) MRI, as well as a more recently developed technique based on arterial spin labeling (ASL). DCE MRI and ASL are thought to measure complementary characteristics of the BBB. Furthermore, we describe clinical studies that have utilized these MRI techniques in cSVD and neurodegenerative diseases, particularly Alzheimer's disease (AD). These studies demonstrate the role of PVS and BBB dysfunction in these diseases and provide insight into the large overlap, but also into the differences between cSVD and AD. Overall, MRI techniques may provide valuable insights into the pathophysiological mechanisms underlying these diseases and have the potential to be used as markers for disease progression and treatment response. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.
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Affiliation(s)
- Paulien H M Voorter
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, the Netherlands
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Maud van Dinther
- School for Cardiovascular Disease, Maastricht University, Maastricht, the Netherlands
- Department of Neurology, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Willemijn J Jansen
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
- Department of Psychiatry and Neuropsychology, Alzheimer Center Limburg, Maastricht University, Maastricht, the Netherlands
| | - Alida A Postma
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Julie Staals
- School for Cardiovascular Disease, Maastricht University, Maastricht, the Netherlands
- Department of Neurology, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Jacobus F A Jansen
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, the Netherlands
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
- Department of Electrical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Robert J van Oostenbrugge
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
- School for Cardiovascular Disease, Maastricht University, Maastricht, the Netherlands
- Department of Neurology, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Merel M van der Thiel
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, the Netherlands
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
- Department of Psychiatry and Neuropsychology, Alzheimer Center Limburg, Maastricht University, Maastricht, the Netherlands
| | - Walter H Backes
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, the Netherlands
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
- School for Cardiovascular Disease, Maastricht University, Maastricht, the Netherlands
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Rowsthorn E, Pham W, Nazem-Zadeh MR, Law M, Pase MP, Harding IH. Imaging the neurovascular unit in health and neurodegeneration: a scoping review of interdependencies between MRI measures. Fluids Barriers CNS 2023; 20:97. [PMID: 38129925 PMCID: PMC10734164 DOI: 10.1186/s12987-023-00499-0] [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: 10/03/2023] [Accepted: 12/05/2023] [Indexed: 12/23/2023] Open
Abstract
The neurovascular unit (NVU) is a complex structure that facilitates nutrient delivery and metabolic waste clearance, forms the blood-brain barrier (BBB), and supports fluid homeostasis in the brain. The integrity of NVU subcomponents can be measured in vivo using magnetic resonance imaging (MRI), including quantification of enlarged perivascular spaces (ePVS), BBB permeability, cerebral perfusion and extracellular free water. The breakdown of NVU subparts is individually associated with aging, pathology, and cognition. However, how these subcomponents interact as a system, and how interdependencies are impacted by pathology remains unclear. This systematic scoping review identified 26 studies that investigated the inter-relationships between multiple subcomponents of the NVU in nonclinical and neurodegenerative populations using MRI. A further 112 studies investigated associations between the NVU and white matter hyperintensities (WMH). We identify two putative clusters of NVU interdependencies: a 'vascular' cluster comprising BBB permeability, perfusion and basal ganglia ePVS; and a 'fluid' cluster comprising ePVS, free water and WMH. Emerging evidence suggests that subcomponent coupling within these clusters may be differentially related to aging, neurovascular injury or neurodegenerative pathology.
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Affiliation(s)
- Ella Rowsthorn
- Department of Neuroscience, Central Clinical School, Monash University, 99 Commercial Road, Melbourne, VIC, 3004, Australia
- Turner Institute for Brain and Mental Health & School of Psychological Sciences, Monash University, 18 Innovation Walk, Clayton, VIC, 3168, Australia
| | - William Pham
- Department of Neuroscience, Central Clinical School, Monash University, 99 Commercial Road, Melbourne, VIC, 3004, Australia
| | - Mohammad-Reza Nazem-Zadeh
- Department of Neuroscience, Central Clinical School, Monash University, 99 Commercial Road, Melbourne, VIC, 3004, Australia
| | - Meng Law
- Department of Neuroscience, Central Clinical School, Monash University, 99 Commercial Road, Melbourne, VIC, 3004, Australia
- Department of Radiology, Alfred Health, 99 Commercial Road, Melbourne, VIC, 3004, Australia
- Department of Electrical and Computer Systems Engineering, Monash University, 14 Alliance Lane, Clayton, VIC, 3168, Australia
| | - Matthew P Pase
- Turner Institute for Brain and Mental Health & School of Psychological Sciences, Monash University, 18 Innovation Walk, Clayton, VIC, 3168, Australia
- Harvard T.H. Chan School of Public Health, 677 Huntington Avenue, Boston, MA, 02115, USA
| | - Ian H Harding
- Department of Neuroscience, Central Clinical School, Monash University, 99 Commercial Road, Melbourne, VIC, 3004, Australia.
- Monash Biomedical Imaging, Monash University, 762-772 Blackburn Road, Clayton, VIC, 3168, Australia.
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Goldwaser EL, Wang DJJ, Adhikari BM, Chiappelli J, Shao X, Yu J, Lu T, Chen S, Marshall W, Yuen A, Kvarta M, Ma Y, Du X, Gao S, Saeedi O, Bruce H, Donnelly P, O’Neill H, Shuldiner AR, Mitchell BD, Kochunov P, Hong LE. Evidence of Neurovascular Water Exchange and Endothelial Vascular Dysfunction in Schizophrenia: An Exploratory Study. Schizophr Bull 2023; 49:1325-1335. [PMID: 37078962 PMCID: PMC10483475 DOI: 10.1093/schbul/sbad057] [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] [Indexed: 04/21/2023]
Abstract
BACKGROUND AND HYPOTHESIS Mounting evidence supports cerebrovascular contributions to schizophrenia spectrum disorder (SSD) but with unknown mechanisms. The blood-brain barrier (BBB) is at the nexus of neural-vascular exchanges, tasked with regulating cerebral homeostasis. BBB abnormalities in SSD, if any, are likely more subtle compared to typical neurological insults and imaging measures that assess large molecule BBB leakage in major neurological events may not be sensitive enough to directly examine BBB abnormalities in SSD. STUDY DESIGN We tested the hypothesis that neurovascular water exchange (Kw) measured by non-invasive diffusion-prepared arterial spin label MRI (n = 27 healthy controls [HC], n = 32 SSD) is impaired in SSD and associated with clinical symptoms. Peripheral vascular endothelial health was examined by brachial artery flow-mediated dilation (n = 44 HC, n = 37 SSD) to examine whether centrally measured Kw is related to endothelial functions. STUDY RESULTS Whole-brain average Kw was significantly reduced in SSD (P = .007). Exploratory analyses demonstrated neurovascular water exchange reductions in the right parietal lobe, including the supramarginal gyrus (P = .002) and postcentral gyrus (P = .008). Reduced right superior corona radiata (P = .001) and right angular gyrus Kw (P = .006) was associated with negative symptoms. Peripheral endothelial function was also significantly reduced in SSD (P = .0001). Kw in 94% of brain regions in HC positively associated with peripheral endothelial function, which was not observed in SSD, where the correlation was inversed in 52% of brain regions. CONCLUSIONS This study provides initial evidence of neurovascular water exchange abnormalities, which appeared clinically associated, especially with negative symptoms, in schizophrenia.
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Affiliation(s)
- Eric L Goldwaser
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Danny J J Wang
- Laboratory of FMRI Technology (LOFT), Mark & Mary Stevens Nueroimaging and Informatics Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Bhim M Adhikari
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Joshua Chiappelli
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Xingfeng Shao
- Laboratory of FMRI Technology (LOFT), Mark & Mary Stevens Nueroimaging and Informatics Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Jiaao Yu
- Department of Mathematics, University of Maryland, College Park, MD, USA
| | - Tong Lu
- Department of Mathematics, University of Maryland, College Park, MD, USA
| | - Shuo Chen
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Mathematics, University of Maryland, College Park, MD, USA
| | - Wyatt Marshall
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Alexa Yuen
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Mark Kvarta
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Yizhou Ma
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Xiaoming Du
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Si Gao
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Osamah Saeedi
- Department of Ophthalmology and Visual Sciences, University of Maryland Medical Center, Baltimore, MD, USA
| | - Heather Bruce
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Patrick Donnelly
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Hugh O’Neill
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Alan R Shuldiner
- Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Braxton D Mitchell
- Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
- Geriatrics Research and Education Clinical Center, Baltimore Veterans Administration Medical Center, Baltimore, MD, USA
| | - Peter Kochunov
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - L Elliot Hong
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
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Levendovszky SR, Flores J, Peskind ER, Václavů L, van Osch MJP, Iliff J. Preliminary cross-sectional investigations into the human glymphatic system using multiple novel non-contrast MRI methods. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.28.555150. [PMID: 37693445 PMCID: PMC10491115 DOI: 10.1101/2023.08.28.555150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
We discuss two potential non-invasive MRI methods to cross-sectionally study two distinct facets of the glymphatic system and its association with sleep and aging. We apply diffusion-based intravoxel incoherent motion (IVIM) imaging to evaluate pseudodiffusion coefficient, D * , or cerebrospinal fluid (CSF) movement across large spaces like the subarachnoid space (SAS). We also performed perfusion-based multi-echo, Hadamard encoded multi-delay arterial spin labeling (ASL) to evaluate whole brain cortical cerebral blood flow (CBF) and transendothelial exchange (Tex) of water from the vasculature into the perivascular space and parenchyma. Both methods were used in young adults (N=9, 6F, 23±3 years old) in the setting of sleep and sleep deprivation. To study aging, 10 older adults, (6F, 67±3 years old) were imaged after a night of normal sleep only and compared with the young adults. D * in SAS was significantly (p<0.05) lesser after sleep deprivation (0.014±0.001 mm2/s) than after normal sleep (0.016±0.001 mm2/s), but was unchanged with aging. Cortical CBF and Tex on the other hand, were unchanged after sleep deprivation but were significantly lower in older adults (37±3 ml/100g/min, 476±66 ms) than young adults (42±2 ml/100g/min, 624±66 ms). IVIM was thus, sensitive to sleep physiology and multi-echo, multi-delay ASL was sensitive to aging.
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Affiliation(s)
- Swati Rane Levendovszky
- Department of Radiology, University of Washington School of Medicine, 1959 NE Pacific Street, Seattle, WA 98195
| | - Jaqueline Flores
- Department of Radiology, University of Washington School of Medicine, 1959 NE Pacific Street, Seattle, WA 98195
| | - Elaine R Peskind
- Mental Illness Research, Education, and Clinical Center, Veterans Affairs Puget Sound Systems, 1660 S Columbian Way, Seattle, WA 98108
| | - Lena Václavů
- C.J. Gorter MRI Center, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Matthias J P van Osch
- C.J. Gorter MRI Center, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Jeffrey Iliff
- Mental Illness Research, Education, and Clinical Center, Veterans Affairs Puget Sound Systems, 1660 S Columbian Way, Seattle, WA 98108
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Uchida Y, Kan H, Furukawa G, Onda K, Sakurai K, Takada K, Matsukawa N, Oishi K. Relationship between brain iron dynamics and blood-brain barrier function during childhood: a quantitative magnetic resonance imaging study. Fluids Barriers CNS 2023; 20:60. [PMID: 37592310 PMCID: PMC10433620 DOI: 10.1186/s12987-023-00464-x] [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: 07/07/2023] [Accepted: 08/14/2023] [Indexed: 08/19/2023] Open
Abstract
BACKGROUND Mounting evidence suggests that the blood-brain barrier (BBB) plays an important role in the regulation of brain iron homeostasis in normal brain development, but these imaging profiles remain to be elucidated. We aimed to establish a relationship between brain iron dynamics and BBB function during childhood using a combined quantitative magnetic resonance imaging (MRI) to depict both physiological systems along developmental trajectories. METHODS In this single-center prospective study, consecutive outpatients, 2-180 months of age, who underwent brain MRI (3.0-T scanner; Ingenia; Philips) between January 2020 and January 2021, were included. Children with histories of preterm birth or birth defects, abnormalities on MRI, and diagnoses that included neurological diseases during follow-up examinations through December 2022 were excluded. In addition to clinical MRI, quantitative susceptibility mapping (QSM; iron deposition measure) and diffusion-prepared pseudo-continuous arterial spin labeling (DP-pCASL; BBB function measure) were acquired. Atlas-based analyses for QSM and DP-pCASL were performed to investigate developmental trajectories of regional brain iron deposition and BBB function and their relationships. RESULTS A total of 78 children (mean age, 73.8 months ± 61.5 [SD]; 43 boys) were evaluated. Rapid magnetic susceptibility progression in the brain (Δsusceptibility value) was observed during the first two years (globus pallidus, 1.26 ± 0.18 [× 10- 3 ppm/month]; substantia nigra, 0.68 ± 0.16; thalamus, 0.15 ± 0.04). The scattergram between the Δsusceptibility value and the water exchange rate across the BBB (kw) divided by the cerebral blood flow was well fitted to the sigmoidal curve model, whose inflection point differed among each deep gray-matter nucleus (globus pallidus, 2.96-3.03 [mL/100 g]-1; substantia nigra, 3.12-3.15; thalamus, 3.64-3.67) in accordance with the regional heterogeneity of brain iron accumulation. CONCLUSIONS The combined quantitative MRI study of QSM and DP-pCASL for pediatric brains demonstrated the relationship between brain iron dynamics and BBB function during childhood. TRIAL REGISTRATION UMIN Clinical Trials Registry identifier: UMIN000039047, registered January 6, 2020.
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Affiliation(s)
- Yuto Uchida
- Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, 208 Traylor Building, 720 Rutland Avenue, Baltimore, MD, 21205, USA.
- Department of Neurology, Nagoya City University Graduate School of Medical Sciences, 1, Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Aichi, Japan.
| | - Hirohito Kan
- Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, 1- 1-20, Daiko-Minami, Higashi-ku, Nagoya, 461-8673, Aichi, Japan
| | - Gen Furukawa
- Department of Pediatrics, Fujita Health University School of Medicine, 1-98, Kutsukake-cho, Dengakugakubo, Toyoake, 470-1192, Aichi, Japan
| | - Kengo Onda
- Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, 208 Traylor Building, 720 Rutland Avenue, Baltimore, MD, 21205, USA
| | - Keita Sakurai
- Department of Radiology, National Center for Geriatrics and Gerontology, Morioka-cho, Obu, 474-8511, Aichi, Japan
| | - Koji Takada
- Department of Neurology, Toyokawa City Hospital, 23, Noji, Yawata-cho, Toyokawa, 442-0857, Aichi, Japan
| | - Noriyuki Matsukawa
- Department of Neurology, Nagoya City University Graduate School of Medical Sciences, 1, Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Aichi, Japan
| | - Kenichi Oishi
- Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, 208 Traylor Building, 720 Rutland Avenue, Baltimore, MD, 21205, USA
- The Richman Family Precision Medicine Center of Excellence in Alzheimer's Disease, Baltimore, MD, 21224, USA
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11
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Yue JH, Zhang QH, Yang X, Wang P, Sun XC, Yan SY, Li A, Zhao WW, Cao DN, Wang Y, Wei ZY, Li XL, Zhu LW, Yang G, Mah JZ. Magnetic resonance imaging of white matter in Alzheimer's disease: a global bibliometric analysis from 1990 to 2022. Front Neurosci 2023; 17:1163809. [PMID: 37304017 PMCID: PMC10248146 DOI: 10.3389/fnins.2023.1163809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Accepted: 04/26/2023] [Indexed: 06/13/2023] Open
Abstract
Background Alzheimer's disease (AD) is a common, progressive, irreversible, and fatal neurodegenerative disorder with rapidly increasing worldwide incidence. Although much research on magnetic resonance imaging (MRI) of the white matter (WM) in AD has been published, no bibliometric analysis study has investigated this issue. Thus, this study aimed to provide an overview of the current status, hotspots, and trends in MRI of WM in AD. Methods We searched for records related to MRI studies of WM in AD from 1990 to 2022 in the Web of Science Core Collection (WOSCC) database. CiteSpace (version 5.1.R8) and VOSviewer (version 1.6.19) software were used for bibliometric analyses. Results A total of 2,199 articles were obtained from this study. From 1990 to 2022, the number of published articles showed exponential growth of y = 4.1374e0.1294x, with an average of 17.9 articles per year. The top country and institutions were the United States and the University of California Davis, accounting for 44.52 and 5.32% of the total studies, respectively. The most productive journal was Neurology, and the most co-cited journal was Lancet Neurology. Decarli C was the most productive author. The current research frontier trend focuses on the association between small vessel disease and AD, the clinical application and exploration of diffusion MRI, and related markers. Conclusion This study provides an in-depth overview of publications on MRI of WM in AD, identifying the current research status, hotspots, and frontier trends in the field.
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Affiliation(s)
- Jin-huan Yue
- Department of Tuina, Acupuncture and Moxibustion, Shenzhen Jiuwei Chinese Medicine Clinic, Shenzhen, China
| | - Qin-hong Zhang
- Department of Tuina, Acupuncture and Moxibustion, Shenzhen Jiuwei Chinese Medicine Clinic, Shenzhen, China
| | - Xu Yang
- Graduate School of Heilongjiang University of Chinese Medicine, Harbin, China
| | - Peng Wang
- Department of Oncology, First Affiliated Hospital of Heilongjiang University of Chinese Medicine, Harbin, China
| | - Xu-Chen Sun
- Graduate School of Heilongjiang University of Chinese Medicine, Harbin, China
| | - Shi-Yan Yan
- International Acupuncture and Moxibustion Innovation Institute, School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Ang Li
- Sanofifi-Aventis China Investment Co., Ltd, Beijing, China
| | | | - Dan-Na Cao
- Division of CT and MRI, First Affiliated Hospital of Heilongjiang University of Chinese Medicine, Harbin, China
| | - Yang Wang
- Division of CT and MRI, First Affiliated Hospital of Heilongjiang University of Chinese Medicine, Harbin, China
| | - Ze-Yi Wei
- Graduate School of Heilongjiang University of Chinese Medicine, Harbin, China
| | - Xiao-Ling Li
- Division of CT and MRI, First Affiliated Hospital of Heilongjiang University of Chinese Medicine, Harbin, China
| | - Lu-Wen Zhu
- Department of Rehabilitation, Second Affiliated Hospital of Heilongjiang University of Chinese Medicine, Harbin, China
| | - Guanhu Yang
- Department of Specialty Medicine, Ohio University, Athens, OH, United States
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Uchida Y, Kan H, Sakurai K, Oishi K, Matsukawa N. Contributions of blood-brain barrier imaging to neurovascular unit pathophysiology of Alzheimer's disease and related dementias. Front Aging Neurosci 2023; 15:1111448. [PMID: 36861122 PMCID: PMC9969807 DOI: 10.3389/fnagi.2023.1111448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 01/26/2023] [Indexed: 02/11/2023] Open
Abstract
The blood-brain barrier (BBB) plays important roles in the maintenance of brain homeostasis. Its main role includes three kinds of functions: (1) to protect the central nervous system from blood-borne toxins and pathogens; (2) to regulate the exchange of substances between the brain parenchyma and capillaries; and (3) to clear metabolic waste and other neurotoxic compounds from the central nervous system into meningeal lymphatics and systemic circulation. Physiologically, the BBB belongs to the glymphatic system and the intramural periarterial drainage pathway, both of which are involved in clearing interstitial solutes such as β-amyloid proteins. Thus, the BBB is believed to contribute to preventing the onset and progression for Alzheimer's disease. Measurements of BBB function are essential toward a better understanding of Alzheimer's pathophysiology to establish novel imaging biomarkers and open new avenues of interventions for Alzheimer's disease and related dementias. The visualization techniques for capillary, cerebrospinal, and interstitial fluid dynamics around the neurovascular unit in living human brains have been enthusiastically developed. The purpose of this review is to summarize recent BBB imaging developments using advanced magnetic resonance imaging technologies in relation to Alzheimer's disease and related dementias. First, we give an overview of the relationship between Alzheimer's pathophysiology and BBB dysfunction. Second, we provide a brief description about the principles of non-contrast agent-based and contrast agent-based BBB imaging methodologies. Third, we summarize previous studies that have reported the findings of each BBB imaging method in individuals with the Alzheimer's disease continuum. Fourth, we introduce a wide range of Alzheimer's pathophysiology in relation to BBB imaging technologies to advance our understanding of the fluid dynamics around the BBB in both clinical and preclinical settings. Finally, we discuss the challenges of BBB imaging techniques and suggest future directions toward clinically useful imaging biomarkers for Alzheimer's disease and related dementias.
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Affiliation(s)
- Yuto Uchida
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, United States,*Correspondence: Yuto Uchida, ; Noriyuki Matsukawa,
| | - Hirohito Kan
- Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Keita Sakurai
- Department of Radiology, National Center for Geriatrics and Gerontology, Ōbu, Aichi, Japan
| | - Kenichi Oishi
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Noriyuki Matsukawa
- Department of Neurology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan,*Correspondence: Yuto Uchida, ; Noriyuki Matsukawa,
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13
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Zhang Q, Wu G, Yang Q, Dai G, Li T, Chen P, Li J, Huang W. Survival rate prediction of nasopharyngeal carcinoma patients based on MRI and gene expression using a deep neural network. Cancer Sci 2022; 114:1596-1605. [PMID: 36541519 PMCID: PMC10067413 DOI: 10.1111/cas.15704] [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: 07/13/2022] [Revised: 11/03/2022] [Accepted: 11/09/2022] [Indexed: 12/24/2022] Open
Abstract
To achieve a better treatment regimen and follow-up assessment design for intensity-modulated radiotherapy (IMRT)-treated nasopharyngeal carcinoma (NPC) patients, an accurate progression-free survival (PFS) time prediction algorithm is needed. We propose developing a PFS prediction model of NPC patients after IMRT treatment using a deep learning method and comparing that with the traditional texture analysis method. One hundred and fifty-one NPC patients were included in this retrospective study. T1-weighted, proton density and dynamic contrast-enhanced magnetic resonance (MR) images were acquired. The expression level of five genes (HIF-1α, EGFR, PTEN, Ki-67, and VEGF) and infection of Epstein-Barr (EB) virus were tested. A residual network was trained to predict PFS from MR images. The output as well as patient characteristics were combined using a linear regression model to provide a final PFS prediction. The prediction accuracy was compared with that of the traditional texture analysis method. A regression model combining the deep learning output with HIF-1α expression and Epstein-Barr infection provides the best PFS prediction accuracy (Spearman correlation R2 = 0.53; Harrell's C-index = 0.82; receiver operative curve [ROC] analysis area under the curve [AUC] = 0.88; log-rank test hazard ratio [HR] = 8.45), higher than a regression model combining texture analysis with HIF-1α expression (Spearman correlation R2 = 0.14; Harrell's C-index =0.68; ROC analysis AUC = 0.76; log-rank test HR = 2.85). The deep learning method does not require a manually drawn tumor region of interest. MR image processing using deep learning combined with patient characteristics can provide accurate PFS prediction for nasopharyngeal carcinoma patients and does not rely on specific kernels or tumor regions of interest, which is needed for the texture analysis method.
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Affiliation(s)
- Qihao Zhang
- Department of Radiology, Weill Cornell Medical College, New York, New York, USA
| | - Gang Wu
- Department of Radiotherapy, Hainan General Hospital, Hainan, China
| | - Qianyu Yang
- Department of Radiology, Hainan General Hospital, Hainan, China
| | - Ganmian Dai
- Department of Radiology, Hainan General Hospital, Hainan, China
| | - Tiansheng Li
- Department of Radiology, Hainan General Hospital, Hainan, China
| | - Pianpian Chen
- Department of Pathology, Hainan General Hospital, Hainan, China
| | - Jiao Li
- Department of Pathology, Hainan General Hospital, Hainan, China
| | - Weiyuan Huang
- Department of Radiology, Hainan General Hospital, Hainan, China
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