1
|
Ebrahimi S, Bagchi P. Predicting capillary vessel network hemodynamics in silico by machine learning. PNAS NEXUS 2024; 3:pgae043. [PMID: 38725529 PMCID: PMC11079571 DOI: 10.1093/pnasnexus/pgae043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Accepted: 01/22/2024] [Indexed: 05/12/2024]
Abstract
Blood velocity and red blood cell (RBC) distribution profiles in a capillary vessel cross-section in the microcirculation are generally complex and do not follow Poiseuille's parabolic or uniform pattern. Existing imaging techniques used to map large microvascular networks in vivo do not allow a direct measurement of full 3D velocity and RBC concentration profiles, although such information is needed for accurate evaluation of the physiological variables, such as the wall shear stress (WSS) and near-wall cell-free layer (CFL), that play critical roles in blood flow regulation, disease progression, angiogenesis, and hemostasis. Theoretical network flow models, often used for hemodynamic predictions in experimentally acquired images of the microvascular network, cannot provide the full 3D profiles either. In contrast, such information can be readily obtained from high-fidelity computational models that treat blood as a suspension of deformable RBCs. These models, however, are computationally expensive and not feasible for extension to the microvascular network at large spatial scales up to an organ level. To overcome such limitations, here we present machine learning (ML) models that bypass such expensive computations but provide highly accurate and full 3D profiles of the blood velocity, RBC concentration, WSS, and CFL in every vessel in the microvascular network. The ML models, which are based on artificial neural networks and convolution-based U-net models, predict hemodynamic quantities that compare very well against the true data but reduce the prediction time by several orders. This study therefore paves the way for ML to make detailed and accurate hemodynamic predictions in spatially large microvascular networks at an organ-scale.
Collapse
Affiliation(s)
- Saman Ebrahimi
- Mechanical and Aerospace Engineering Department, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
| | - Prosenjit Bagchi
- Mechanical and Aerospace Engineering Department, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
| |
Collapse
|
2
|
Kiouptsi K, Casari M, Mandel J, Gao Z, Deppermann C. Intravital Imaging of Thrombosis Models in Mice. Hamostaseologie 2023; 43:348-359. [PMID: 37857297 DOI: 10.1055/a-2118-2932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2023] Open
Abstract
Intravital microscopy is a powerful tool to study thrombosis in real time. The kinetics of thrombus formation and progression in vivo is studied after inflicting damage to the endothelium through mechanical, chemical, or laser injury. Mouse models of atherosclerosis are also used to induce thrombus formation. Vessels of different sizes and from different vascular beds such as carotid artery or vena cava, mesenteric or cremaster arterioles, can be targeted. Using fluorescent dyes, antibodies, or reporter mouse strains allows to visualize key cells and factors mediating the thrombotic processes. Here, we review the latest literature on using intravital microscopy to study thrombosis as well as thromboinflammation following transient middle cerebral artery occlusion, infection-induced immunothrombosis, and liver ischemia reperfusion.
Collapse
Affiliation(s)
- Klytaimnistra Kiouptsi
- Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
- German Center for Cardiovascular Research (DZHK), Partner Site Rhine-Main, Mainz, Germany
| | - Martina Casari
- Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Jonathan Mandel
- Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Zhenling Gao
- Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Carsten Deppermann
- Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
- German Center for Cardiovascular Research (DZHK), Partner Site Rhine-Main, Mainz, Germany
| |
Collapse
|
3
|
Taormina V, Raso G, Gentile V, Abbene L, Buttacavoli A, Bonsignore G, Valenti C, Messina P, Scardina GA, Cascio D. Automated Stabilization, Enhancement and Capillaries Segmentation in Videocapillaroscopy. SENSORS (BASEL, SWITZERLAND) 2023; 23:7674. [PMID: 37765731 PMCID: PMC10536112 DOI: 10.3390/s23187674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 08/27/2023] [Accepted: 09/04/2023] [Indexed: 09/29/2023]
Abstract
Oral capillaroscopy is a critical and non-invasive technique used to evaluate microcirculation. Its ability to observe small vessels in vivo has generated significant interest in the field. Capillaroscopy serves as an essential tool for diagnosing and prognosing various pathologies, with anatomic-pathological lesions playing a crucial role in their progression. Despite its importance, the utilization of videocapillaroscopy in the oral cavity encounters limitations due to the acquisition setup, encompassing spatial and temporal resolutions of the video camera, objective magnification, and physical probe dimensions. Moreover, the operator's influence during the acquisition process, particularly how the probe is maneuvered, further affects its effectiveness. This study aims to address these challenges and improve data reliability by developing a computerized support system for microcirculation analysis. The designed system performs stabilization, enhancement and automatic segmentation of capillaries in oral mucosal video sequences. The stabilization phase was performed by means of a method based on the coupling of seed points in a classification process. The enhancement process implemented was based on the temporal analysis of the capillaroscopic frames. Finally, an automatic segmentation phase of the capillaries was implemented with the additional objective of quantitatively assessing the signal improvement achieved through the developed techniques. Specifically, transfer learning of the renowned U-net deep network was implemented for this purpose. The proposed method underwent testing on a database with ground truth obtained from expert manual segmentation. The obtained results demonstrate an achieved Jaccard index of 90.1% and an accuracy of 96.2%, highlighting the effectiveness of the developed techniques in oral capillaroscopy. In conclusion, these promising outcomes encourage the utilization of this method to assist in the diagnosis and monitoring of conditions that impact microcirculation, such as rheumatologic or cardiovascular disorders.
Collapse
Affiliation(s)
- Vincenzo Taormina
- Department of Mathematics and Informatics, University of Palermo, 90128 Palermo, Italy; (V.T.); (C.V.)
| | - Giuseppe Raso
- Department of Physics and Chemistry, University of Palermo, 90128 Palermo, Italy; (G.R.); (V.G.); (L.A.); (A.B.); (G.B.)
| | - Vito Gentile
- Department of Physics and Chemistry, University of Palermo, 90128 Palermo, Italy; (G.R.); (V.G.); (L.A.); (A.B.); (G.B.)
| | - Leonardo Abbene
- Department of Physics and Chemistry, University of Palermo, 90128 Palermo, Italy; (G.R.); (V.G.); (L.A.); (A.B.); (G.B.)
| | - Antonino Buttacavoli
- Department of Physics and Chemistry, University of Palermo, 90128 Palermo, Italy; (G.R.); (V.G.); (L.A.); (A.B.); (G.B.)
| | - Gaetano Bonsignore
- Department of Physics and Chemistry, University of Palermo, 90128 Palermo, Italy; (G.R.); (V.G.); (L.A.); (A.B.); (G.B.)
| | - Cesare Valenti
- Department of Mathematics and Informatics, University of Palermo, 90128 Palermo, Italy; (V.T.); (C.V.)
| | - Pietro Messina
- Department of Surgical Oncological and Stomatological Disciplines, University of Palermo, 90127 Palermo, Italy; (P.M.); (G.A.S.)
| | - Giuseppe Alessandro Scardina
- Department of Surgical Oncological and Stomatological Disciplines, University of Palermo, 90127 Palermo, Italy; (P.M.); (G.A.S.)
| | - Donato Cascio
- Department of Physics and Chemistry, University of Palermo, 90128 Palermo, Italy; (G.R.); (V.G.); (L.A.); (A.B.); (G.B.)
| |
Collapse
|
4
|
Antonelou MH. Tools and metrics for the assessment of post-storage performance of red blood cells: no one is left over. Transfusion 2023; 63:1-6. [PMID: 36537147 DOI: 10.1111/trf.17228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 12/07/2022] [Indexed: 12/24/2022]
Affiliation(s)
- Marianna H Antonelou
- Department of Biology, School of Science, National and Kapodistrian University of Athens (NKUA), Panepistimiopolis, Athens, Greece
| |
Collapse
|
5
|
Janssen BGH, Zhang YM, Kosik I, Akbari A, McIntyre CW. Intravital microscopic observation of the microvasculature during hemodialysis in healthy rats. Sci Rep 2022; 12:191. [PMID: 34996931 PMCID: PMC8741960 DOI: 10.1038/s41598-021-03681-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 12/08/2021] [Indexed: 11/09/2022] Open
Abstract
Hemodialysis (HD) provides life-saving treatment for kidney failure. Patient mortality is extremely high, with cardiovascular disease (CVD) being the leading cause of death. This results from both a high underlying burden of cardiovascular disease, as well as additional physiological stress from the HD procedure itself. Clinical observations indicate that HD is associated with microvascular dysfunction (MD), underlining the need for a fundamental pathophysiological assessment of the microcirculatory consequences of HD. We therefore successfully developed an experimental small animal model, that allows for a simultaneous real-time assessment of the microvasculature. Using in-house built ultra-low surface area dialyzers and miniaturized extracorporeal circuit, we successfully dialyzed male Wistar Kyoto rats and combined this with a simultaneous intravital microscopic observation of the EDL microvasculature. Our results show that even in healthy animals, a euvolemic HD procedure can induce a significant systemic hemodynamic disturbance and induce disruption of microvascular perfusion (as evidence by a reduction in the proportion of the observed microcirculation receiving blood flow). This study, using a new small animal hemodialysis model, has allowed direct demonstration that microvascular blood flow in tissue in skeletal muscle is acutely reduced during HD, potentially in concert with other microvascular beds. It shows that preclinical small animal models can be used to further investigate HD-induced ischemic organ injury and allow rapid throughput of putative interventions directed at reducing HD-induced multi-organ ischemic injury.
Collapse
Affiliation(s)
- B G H Janssen
- Department of Medical Biophysics, Western University, London, ON, Canada.
- Kidney Clinical Research Unit, Lawson Health Research Institute, London, ON, Canada.
- Kidney Clinical Research Unit (KCRU), London Health Sciences Centre, 800 Commissioners Rd. East, London, ON, N6C 6B5, Canada.
| | - Y M Zhang
- Department of Medical Biophysics, Western University, London, ON, Canada
- Kidney Clinical Research Unit, Lawson Health Research Institute, London, ON, Canada
- Trauma Research Centre, Fourth Medical Center of the Chinese PLA General Hospital, Beijing, 100048, People's Republic of China
- Intensive Care Unit, Tianjin Nankai Hospital, Tianjin, 300100, People's Republic of China
| | - I Kosik
- Kidney Clinical Research Unit, Lawson Health Research Institute, London, ON, Canada
- Imaging Program, Lawson Health Research Institute, St. Joseph's Health Care, London, ON, Canada
| | - A Akbari
- Kidney Clinical Research Unit, Lawson Health Research Institute, London, ON, Canada
- Robarts Research Institute, Western University, London, ON, Canada
| | - C W McIntyre
- Department of Medical Biophysics, Western University, London, ON, Canada
- Kidney Clinical Research Unit, Lawson Health Research Institute, London, ON, Canada
| |
Collapse
|