Article
Endocrinology & Metabolism
Per Kristian Eide, Are Hugo Pripp, Benedikte Berge, Harald Hrubos-Strom, Geir Ringstad, Lars Magnus Valnes
Summary: Chronic sleep disturbance is associated with impaired clearance of metabolic by-products in the brain, increasing the risk of dementia disease. Using the Pittsburgh Sleep Quality Index questionnaire, we compared tracer enrichment in the brain of patients with good or poor sleep quality using magnetic resonance imaging. The results showed that sleep impairment was correlated with increased tracer enrichment in multiple brain regions, as well as reduced brain volume and cortex thickness. We suggest that chronic sleep disturbance may be related to impaired glymphatic function in the brain.
JOURNAL OF CEREBRAL BLOOD FLOW AND METABOLISM
(2022)
Article
Medicine, Research & Experimental
Mohammed S. Alshuhri, Lindsay Gallagher, Lorraine M. Work, William M. Holmes
Summary: The recently proposed glymphatic pathway for solute transport and waste clearance from the brain has been the focus of intense debate. By using an isotopically enriched MRI tracer, researchers directly imaged glymphatic water transport in the rat brain in vivo, revealing faster and more extensive transport than previously thought, with aquaporin-4 channels playing a critical role.
Article
Veterinary Sciences
Hyunju Cho, Yejin Kim, Saebyel Hong, Hojung Choi
Summary: This study used magnetic resonance imaging to obtain cerebrospinal fluid flow velocity data in healthy beagle dogs, finding bidirectional flow in the subarachnoid space and cerebral aqueduct. A reference dataset of peak velocities of cerebrospinal fluid flow in healthy dogs was successfully obtained.
JOURNAL OF VETERINARY SCIENCE
(2021)
Article
Oncology
Jan Remsik, Jessica A. Wilcox, N. Esther Babady, Tracy A. McMillen, Behroze A. Vachha, Neil A. Halpern, Vikram Dhawan, Marc Rosenblum, Christine A. Iacobuzio-Donahue, Edward K. Avila, Bianca Santomasso, Adrienne Boire
Summary: Cancer patients with neurologic sequelae of COVID-19 have meningeal inflammatory cytokines without viral neuroinvasion, mainly driven by type II interferon and correlated with the degree of neurological dysfunction. The neuroinflammatory process persists weeks after recovery from acute respiratory infection, leading to long-term neurocognitive dysfunction. Anti-inflammatory treatments may play a role in managing neurological complications of COVID-19 infection.
Article
Clinical Neurology
Brian T. Gold, Xingfeng Shao, Tiffany L. Sudduth, Gregory A. Jicha, Donna M. Wilcock, Elayna R. Seago, Danny J. J. Wang
Summary: The water exchange rate across the blood-brain barrier (BBB), estimated with MRI, was positively associated with CSF amyloid beta (A beta)42 concentration levels in multiple brain regions, but only moderately associated with neuropsychological performance. This suggests that the water exchange rate may be a promising indicator of BBB A beta clearance functions.
ALZHEIMERS & DEMENTIA
(2021)
Article
Radiology, Nuclear Medicine & Medical Imaging
Johannes Toger, Mads Andersen, Olle Haglund, Tekla Maria Kylkilahti, Iben Lundgaard, Karin Markenroth Bloch
Summary: In this study, a real-time flow MRI method was developed to quantify respiratory-related variations of cerebrospinal fluid (CSF) flow in the cerebral aqueduct. The method showed good repeatability and a relationship between flow and respiration in both phantom and in vivo experiments.
MAGNETIC RESONANCE IN MEDICINE
(2022)
Article
Clinical Neurology
Laura Stankeviciute, Carles Falcon, Gregory Operto, Marina Garcia, Mahnaz Shekari, Alex Iranzo, Aida Ninerola-Baizan, Andres Perissinotti, Carolina Minguillon, Karine Fauria, Jose Luis Molinuevo, Henrik Zetterberg, Kaj Blennow, Marc Suarez-Calvet, Raffaele Cacciaglia, Juan Domingo Gispert, Oriol Grau-Rivera
Summary: This study analyzed the associations between self-reported sleep quality and brain structure and function in cognitively unimpaired individuals. The results showed that poorer sleep quality was associated with lower gray matter volumes and cerebral glucose metabolism in the orbitofrontal and cingulate cortices, independently of Alzheimer's disease pathology. This suggests that poor sleep quality may impact brain structure and function independently of Alzheimer's disease pathology.
ALZHEIMERS & DEMENTIA
(2023)
Article
Neurosciences
Carolina Gonzalez-Riano, Jorge Saiz, Coral Barbas, Alberto Bergareche, Jose Ma Huerta, Eva Ardanaz, Marcela Konjevod, Elisabet Mondragon, M. E. Erro, M. Dolores Chirlaque, Eunate Abilleira, Fernando Goni-Irigoyen, Pilar Amiano
Summary: The study utilized metabolomics to analyze plasma samples of PD patients and found significantly lower levels of FFAs before clinical symptoms appeared, revealing changes prior to PD development. These findings may serve as valuable biomarkers for early prediction of PD.
NPJ PARKINSONS DISEASE
(2021)
Review
Otorhinolaryngology
Do Hyun Kim, Sung Won Kim, So-Hyun Kim, Jae Hoon Jung, Se Hwan Hwang
Summary: Imaging studies can be used for the diagnosis of CSF rhinorrhea with certain localization usefulness, with gadolinium magnetic resonance cisternography demonstrating the highest diagnostic accuracy.
INTERNATIONAL FORUM OF ALLERGY & RHINOLOGY
(2022)
Article
Biophysics
Jun-Hee Kim, Jae-Geun Im, Sung-Hong Park
Summary: This study proposes a new approach to studying the alteration of cerebrospinal fluid (CSF) dynamics in traumatic brain injury (TBI) patients. The findings suggest that the decreased CSF pulsation after TBI could lead to the accumulation of toxic substances in the brain and have an adverse effect on brain function.
NMR IN BIOMEDICINE
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
Paul D. Griffiths, Mariasavina Severino, Deborah Jarvis, Laura Mandefield, Cecilia Parazzini, Lorenzo Pinelli, Marco Di Maurizio, Fabio Triulzi, Elisa Scola, Giorgio Conte, Giovanni Palumbo, Maurilio Genovese, Andrea Rossi, Renzo Guerrini, Andrea Righini
Summary: The study included 64 foetuses with cortical formation abnormalities (CFA) who underwent two in utero magnetic resonance (iuMR) exams, with 62% showing consistent CFA description between the two studies. In 38% of cases, there was a category change, including cases without CFA initially detected, changes in laterality/symmetry, and re-classification within the same group. Brain abnormalities other than CFA were present in around half of the cases on both first and second studies. Prognosis was predicted to have changed in 8% of cases based on the second study, with all indicating a worse prognosis.
EUROPEAN RADIOLOGY
(2021)
Article
Neurosciences
Nao-Xin Huang, Zhu-Ling Gao, Jia-Hui Lin, Yan-Juan Lin, Hua-Jun Chen
Summary: Sleep deprivation can alter the stability of the brain's functional architecture and may have implications for various neurocognitive domains.
FRONTIERS IN NEUROSCIENCE
(2022)
Article
Biophysics
Shusaku Maeda, Tomohiro Otani, Shigeki Yamada, Yoshiyuki Watanabe, Selin Yavuz Ilik, Shigeo Wada
Summary: Normal pressure hydrocephalus (NPH) is characterized by abnormal accumulation of cerebrospinal fluid (CSF) in the brain ventricles. This study used computational simulations to examine the biomechanical effects of CSF flow in NPH patients. The results showed that NPH patients had higher CSF flow rates and irregular aqueduct shapes compared to healthy controls, leading to increased wall shear stress and flow mixing. These findings provide insights into the pathophysiology of NPH.
JOURNAL OF BIOMECHANICS
(2023)
Article
Geriatrics & Gerontology
Georgy Berezhnoy, Christoph Laske, Christoph Trautwein
Summary: This study quantified a set of metabolites in the cerebrospinal fluid (CSF) and serum using nuclear magnetic resonance (NMR) metabolomics, and found metabolic changes in patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD). The levels of the ketone body acetoacetate were significantly reduced in the CSF and serum of AD and MCI patients. Additionally, decreased levels of the branched-chain amino acid valine and altered CSF protein content were observed in AD patients.
FRONTIERS IN AGING NEUROSCIENCE
(2023)
Review
Radiology, Nuclear Medicine & Medical Imaging
So Jeong Lee, Dana Kim, Chong Hyun Suh, Hwon Heo, Woo Hyun Shim, Sang Joon Kim
Summary: The study aimed to investigate the overall diagnostic yield of MR myelography in patients with newly diagnosed spontaneous intracranial hypotension (SIH). The results showed that the diagnostic yield of MR myelography was 86%, and that of MR myelography with intrathecal gadolinium was 83%. Subgroup analysis indicated that the diagnostic yield of epidural fluid collection was 91%. Meta-regression analysis demonstrated that the diagnostic yield was unaffected by consecutive enrollment, magnet strength, or 2D/3D.
EUROPEAN RADIOLOGY
(2022)
Article
Engineering, Biomedical
Matteo Croci, Vegard Vinje, Marie E. Rognes
Summary: This paper investigates uncertainty quantification methods in tracer transport models within the brain, showing that when there are fewer random inputs, quasi Monte Carlo method outperforms standard Monte Carlo simulations. Multilevel Monte Carlo method considerably outperforms both quasi Monte Carlo and standard Monte Carlo methods, making it a preferred choice for brain transport models.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING
(2021)
Article
Mathematics, Applied
Kent-Andre Mardal, Jarle Sogn, Stefan Takacs
Summary: In this paper, an optimization problem with limited observation governed by a convection-diffusion-reaction equation is analyzed. Continuous norms are derived to analyze well-posedness and derive error analysis and a robust preconditioner for the problem parameters. Conditions for inf-sup stable discretizations are provided, and a discretization for box domains with constant convection is presented.
SIAM JOURNAL ON NUMERICAL ANALYSIS
(2022)
Article
Biochemical Research Methods
Miroslav Kuchta, Sileshi Gizachew Wubshet, Nils Kristian Afseth, Kent-Andre Mardal, Kristian Hovde Liland
Summary: This study investigates the potential of deep neural networks in predicting the future state of enzymatic hydrolysis, described by Fourier-transform infrared spectra of the hydrolysates. Combined with predictions of average molecular weight, this provides a flexible and transparent tool for process monitoring and control.
JOURNAL OF BIOPHOTONICS
(2022)
Article
Multidisciplinary Sciences
Jakob Schreiner, Kent-Andre Mardal
Summary: This study extends previous models of epileptic seizures on the neuronal level to the whole brain using the Bidomain model. The approach is evaluated in terms of power-law distributions, and the computed electric potentials follow power-law distributions with slopes ranging from 2 to 5 for frequencies greater than 10-30 Hz.
SCIENTIFIC REPORTS
(2022)
Article
Computer Science, Interdisciplinary Applications
Wietse M. Boon, Martin Hornkjol, Miroslav Kuchta, Kent-Andre Mardal, Ricardo Ruiz-Baier
Summary: This paper advances the analysis of discretizations for a fluid-structure interaction model, proposing a five-field mixed-primal finite element scheme and deriving adequate inf-sup conditions. The stability of the formulation is established robustly in all material parameters and its performance is corroborated by several test cases.
JOURNAL OF COMPUTATIONAL PHYSICS
(2022)
Article
Mathematics, Applied
Wietse M. Boon, Timo Koch, Miroslav Kuchta, Kent-Andre Mardal
Summary: This paper presents mesh-independent and parameter-robust monolithic solvers for the coupled primal Stokes-Darcy problem, considering three different formulations and their discretizations in various finite element and finite volume methods. Robust preconditioners are derived using a unified theoretical framework, utilizing operators in fractional Sobolev spaces. Numerical experiments demonstrate the parameter-robustness of the proposed solvers.
SIAM JOURNAL ON SCIENTIFIC COMPUTING
(2022)
Article
Multidisciplinary Sciences
Bastian Zapf, Johannes Haubner, Miroslav Kuchta, Geir Ringstad, Per Kristian Eide, Kent-Andre Mardal
Summary: In recent years, various methods combining neural networks and partial differential equations have been developed. This study applies physics-informed neural networks and the finite element method to estimate the diffusion coefficient in the human brain from magnetic resonance images. Synthetic test cases demonstrate that the standard formulation of the physics-informed neural network faces challenges with noisy measurements. The study finds that a small residual of the partial differential equation after training is crucial for accurate parameter recovery.
SCIENTIFIC REPORTS
(2022)
Article
Biotechnology & Applied Microbiology
Martin Hornkjol, Lars Magnus Valnes, Geir Ringstad, Marie E. Rognes, Per-Kristian Eide, Kent-Andre Mardal, Vegard Vinje
Summary: In this paper, a computational model was used to study the clearance of a tracer driven by the circulation of cerebrospinal fluid (CSF) produced in the choroid plexus (CP). It was found that the circulation in the choroid plexus can accelerate the clearance of CSF both in the subarachnoid space and in the brain parenchyma.
FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY
(2022)
Review
Multidisciplinary Sciences
Tomas Bohr, Poul G. Hjorth, Sebastian C. Holst, Sabina Hrabetova, Vesa Kiviniemi, Tuomas Lilius, Iben Lundgaard, Kent-Andre Mardal, Erik A. Martens, Yuki Mori, U. Valentin Nagerl, Charles Nicholson, Allen Tannenbaum, John H. Thomas, Jeffrey Tithof, Helene Benveniste, Jeffrey J. Iliff, Douglas H. Kelley, Maiken Nedergaard
Summary: This article reviews theoretical and numerical models of the glymphatic system, which plays a role in solute transport and has clinical applications in drug delivery, stroke, and neurodegenerative disorders. The authors categorize existing models based on their anatomical functions and highlight the need for future work, including new models and experiments to improve our understanding of the system.
Article
Mathematics, Applied
Qingguo Hong, Johannes Kraus, Miroslav Kuchta, Maria Lymbery, Kent-Andre Mardal, Marie E. Rognes
Summary: This paper introduces a class of three-field finite element formulations for the generalized Biot-Brinkman equations and demonstrates their robustness in different parameter regimes through theoretical analysis and numerical investigation.
JOURNAL OF SCIENTIFIC COMPUTING
(2022)
Meeting Abstract
Endocrinology & Metabolism
Alexandra Vallet, Laura Bojarskaite, Daniel Bjornstad, Miroslav Kuchta, Rune Enger, Kent Mardal
JOURNAL OF CEREBRAL BLOOD FLOW AND METABOLISM
(2022)
Article
Mathematics, Applied
E. Piersanti, J. J. Lee, T. Thompson, K. A. Mardal, M. E. Rognes
Summary: The paper introduces a new strategy for efficiently solving the MPET equations by diagonalizing the element matrices, which is particularly suitable for cases with parameter variability. The approach is demonstrated through the multicompartment Darcy equations and the MPET equations for a nearly incompressible medium with large exchange variability, showing promising theoretical and numerical results.
SIAM JOURNAL ON SCIENTIFIC COMPUTING
(2021)
Article
Mathematics, Applied
Wietse M. Boon, Miroslav Kuchta, Kent-Andre Mardal, Ricardo Ruiz-Baier
Summary: Robust solvers were developed for perturbed saddle-point problems related to a second-order elliptic equation and Biot's consolidation problem for linear poroelasticity. The stability of continuous variational mixed problems and the efficacy of proposed preconditioners were discussed and demonstrated through numerical experiments.
SIAM JOURNAL ON SCIENTIFIC COMPUTING
(2021)
Article
Mathematics, Applied
Miroslav Kuchta, Federica Laurino, Kent-Andre Mardal, Paolo Zunino
Summary: This paper addresses the challenges posed by mixed-dimensional PDEs defined on 3D and 1D domains, and presents a solution using the Lagrange multiplier method for coupling problems. The main challenge in numerical approximation lies in the disc of the Lagrange multiplier space.
SIAM JOURNAL ON NUMERICAL ANALYSIS
(2021)