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Author | Sentürk, D.G.; De Backer, A.; Friedrich, T.; Van Aert, S. | ||||
Title | Optimal experiment design for element specific atom counting using multiple annular dark field scanning transmission electron microscopy detectors | Type | A1 Journal article | ||
Year | 2022 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | 242 | Issue | Pages | 113626 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | This paper investigates the possible benefits for counting atoms of different chemical nature when analysing multiple 2D scanning transmission electron microscopy (STEM) images resulting from independent annular dark field (ADF) detector regimes. To reach this goal, the principles of statistical detection theory are used to quantify the probability of error when determining the number of atoms in atomic columns consisting of multiple types of elements. In order to apply this theory, atom-counting is formulated as a statistical hypothesis test, where each hypothesis corresponds to a specific number of atoms of each atom type in an atomic column. The probability of error, which is limited by the unavoidable presence of electron counting noise, can then be computed from scattering-cross sections extracted from multiple ADF STEM images. Minimisation of the probability of error as a function of the inner and outer angles of a specified number of independent ADF collection regimes results in optimal experimental designs. Based on simulations of spherical Au@Ag and Au@Pt core–shell nanoparticles, we investigate how the combination of two non-overlapping detector regimes helps to improve the probability of error when unscrambling two types of atoms. In particular, the combination of a narrow low angle ADF detector with a detector formed by the remaining annular collection regime is found to be optimal. The benefit is more significant if the atomic number Z difference becomes larger. In addition, we show the benefit of subdividing the detector regime into three collection areas for heterogeneous nanostructures based on a structure consisting of three types of elements, e.g., a mixture of Au, Ag and Al atoms. Finally, these results are compared with the probability of error resulting when one would ultimately use a pixelated 4D STEM detector and how this could help to further reduce the incident electron dose. |
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Language | Wos | 000873778100001 | Publication Date | 0000-00-00 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.2 | Times cited | Open Access | OpenAccess | |
Notes | This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S. Van Aert and Grant 823717 ESTEEM3). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0346.21N and EOS 30489208) and a postdoctoral grant to A. De Backer. S. Van Aert acknowledges funding from the University of Antwerp Research fund (BOF).; esteem3reported; esteem3jra | Approved | Most recent IF: 2.2 | ||
Call Number | EMAT @ emat @c:irua:190925 | Serial | 7118 | ||
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Author | De Backer, A.; Bals, S.; Van Aert, S. | ||||
Title | A decade of atom-counting in STEM: From the first results toward reliable 3D atomic models from a single projection | Type | A1 Journal article | ||
Year | 2023 | Publication | Ultramicroscopy | Abbreviated Journal | |
Volume | Issue | Pages | 113702 | ||
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Quantitative structure determination is needed in order to study and understand nanomaterials at the atomic scale. Materials characterisation resulting in precise structural information is a crucial point to understand the structure–property relation of materials. Counting the number of atoms and retrieving the 3D atomic structure of nanoparticles plays an important role here. In this paper, an overview will be given of the atom-counting methodology and its applications over the past decade. The procedure to count the number of atoms will be discussed in detail and it will be shown how the performance of the method can be further improved. Furthermore, advances toward mixed element nanostructures, 3D atomic modelling based on the atom-counting results, and quantifying the nanoparticle dynamics will be highlighted. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000953765800001 | Publication Date | 2023-02-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.2 | Times cited | 3 | Open Access | OpenAccess |
Notes | This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S. Van Aert, Grant 815128 REALNANO to S. Bals, and Grant 823717 ESTEEM3). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0267.18N, G.0502.18N, G.0346.21N, and EOS 30489208) and a postdoctoral grant to A. De Backer. S. Van Aert acknowledges funding from the University of Antwerp Research fund (BOF) . The authors also thank the colleagues who have contributed to this work over the years, including T. Altantzis, E. Arslan Irmak, K.J. Batenburg, E. Bladt, A. De wael, R. Erni, C. Faes, B. Goris, L. Jones, L.M. Liz-Marzán, I. Lobato, G.T. Martinez, P.D. Nellist, M.D. Rosell, A. Rosenauer, K.H.W. van den Bos, A. Varambhia, and Z. Zhang.; esteem3reported; esteem3JRA | Approved | Most recent IF: 2.2; 2023 IF: 2.843 | ||
Call Number | EMAT @ emat @c:irua:195896 | Serial | 7236 | ||
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Author | Lin, A.; Sahun, M.; Biscop, E.; Verswyvel, H.; De Waele, J.; De Backer, J.; Theys, C.; Cuypers, B.; Laukens, K.; Berghe, W.V.; Smits, E.; Bogaerts, A. | ||||
Title | Acquired non-thermal plasma resistance mediates a shift towards aerobic glycolysis and ferroptotic cell death in melanoma | Type | A1 Journal article | ||
Year | 2023 | Publication | Drug resistance updates | Abbreviated Journal | |
Volume | 67 | Issue | Pages | 100914 | |
Keywords | A1 Journal article; Pharmacology. Therapy; ADReM Data Lab (ADReM); Center for Oncological Research (CORE); Proteinscience, proteomics and epigenetic signaling (PPES); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | To gain insights into the underlying mechanisms of NTP therapy sensitivity and resistance, using the firstever NTP-resistant cell line derived from sensitive melanoma cells (A375). Methods: Melanoma cells were exposed to NTP and re-cultured for 12 consecutive weeks before evaluation against the parental control cells. Whole transcriptome sequencing analysis was performed to identify differentially expressed genes and enriched molecular pathways. Glucose uptake, extracellular lactate, media acidification, and mitochondrial respiration was analyzed to determine metabolic changes. Cell death inhibitors were used to assess the NTP-induced cell death mechanisms, and apoptosis and ferroptosis was further validated via Annexin V, Caspase 3/7, and lipid peroxidation analysis. Results: Cells continuously exposed to NTP became 10 times more resistant to NTP compared to the parental cell line of the same passage, based on their half-maximal inhibitory concentration (IC50). Sequencing and metabolic analysis indicated that NTP-resistant cells had a preference towards aerobic glycolysis, while cell death analysis revealed that NTP-resistant cells exhibited less apoptosis but were more vulnerable to lipid peroxidation and ferroptosis. Conclusions: A preference towards aerobic glycolysis and ferroptotic cell death are key physiological changes in NTP-resistance cells, which opens new avenues for further, in-depth research into other cancer types. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000925156500001 | Publication Date | 2022-12-29 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1368-7646 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 24.3 | Times cited | Open Access | OpenAccess | |
Notes | The authors would like to thank Dr. Christophe Deben and Ms. Hannah Zaryouh (Center for Oncological Research, University of Antwerp) for the use and their help with the D300e Digital Dispenser and Spark® Cyto, as well as Ms. Rapha¨elle Corremans (Laboratory Pathophysiology, University of Antwerp) for the use of their lactate meter. The authors would also like to acknowledge the help from Ms. Tias Verhezen and Mr. Cyrus Akbari, who was involved at the start of the project but could not continue due to the COVID-19 pandemic. The authors also acknowledge the resources and services provided by the VSC (Flemish Supercomputer Center). This work was funded in part by the Research Foundation – Flanders (FWO) and the Flemish Government. The FWO fellowships and grants that funded this work also include: 12S9221N (Abraham Lin), G044420N (Abraham Lin, Annemie Bogaerts), and 1S67621N (Hanne Verswyvel). We would also like to thank several patrons, as part of this research was funded by donations from different donors, including Dedert Schilde vzw, Mr. Willy Floren, and the Vereycken family. We would also like to acknowledge the support from the European Cooperation in Science & Technology (COST) Action on Therapeutical applications of Cold Plasmas (CA20114; PlasTHER). | Approved | Most recent IF: 24.3; 2023 IF: 10.906 | ||
Call Number | PLASMANT @ plasmant @c:irua:193167 | Serial | 7240 | ||
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Author | Zhang, Z.; Lobato, I.; De Backer, A.; Van Aert, S.; Nellist, P. | ||||
Title | Fast generation of calculated ADF-EDX scattering cross-sections under channelling conditions | Type | A1 Journal article | ||
Year | 2023 | Publication | Ultramicroscopy | Abbreviated Journal | |
Volume | 246 | Issue | Pages | 113671 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Advanced materials often consist of multiple elements which are arranged in a complicated structure. Quantitative scanning transmission electron microscopy is useful to determine the composition and thickness of nanostructures at the atomic scale. However, significant difficulties remain to quantify mixed columns by comparing the resulting atomic resolution images and spectroscopy data with multislice simulations where dynamic scattering needs to be taken into account. The combination of the computationally intensive nature of these simulations and the enormous amount of possible mixed column configurations for a given composition indeed severely hamper the quantification process. To overcome these challenges, we here report the development of an incoherent non-linear method for the fast prediction of ADF-EDX scattering cross-sections of mixed columns under channelling conditions. We first explain the origin of the ADF and EDX incoherence from scattering physics suggesting a linear dependence between those two signals in the case of a high-angle ADF detector. Taking EDX as a perfect incoherent reference mode, we quantitatively examine the ADF longitudinal incoherence under different microscope conditions using multislice simulations. Based on incoherent imaging, the atomic lensing model previously developed for ADF is now expanded to EDX, which yields ADF-EDX scattering cross-section predictions in good agreement with multislice simulations for mixed columns in a core–shell nanoparticle and a high entropy alloy. The fast and accurate prediction of ADF-EDX scattering cross-sections opens up new opportunities to explore the wide range of ordering possibilities of heterogeneous materials with multiple elements. | ||||
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Corporate Author | Zezhong Zhang | Thesis | |||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000995063900001 | Publication Date | 2022-12-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.2 | Times cited | Open Access | OpenAccess | |
Notes | European Research Council 770887 PICOMETRICS; Fonds Wetenschappelijk Onderzoek No.G.0502.18N; Horizon 2020, 770887 ; Horizon 2020 Framework Programme; European Research Council, 823717 ESTEEM3 ; esteem3reported; esteem3JRa | Approved | Most recent IF: 2.2; 2023 IF: 2.843 | ||
Call Number | EMAT @ emat @c:irua:195890 | Serial | 7251 | ||
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Author | Arteaga Cardona, F.; Jain, N.; Popescu, R.; Busko, D.; Madirov, E.; Arús, B.A.; Gerthsen, D.; De Backer, A.; Bals, S.; Bruns, O.T.; Chmyrov, A.; Van Aert, S.; Richards, B.S.; Hudry, D. | ||||
Title | Preventing cation intermixing enables 50% quantum yield in sub-15 nm short-wave infrared-emitting rare-earth based core-shell nanocrystals | Type | A1 Journal article | ||
Year | 2023 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
Volume | 14 | Issue | 1 | Pages | 4462 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Short-wave infrared (SWIR) fluorescence could become the new gold standard in optical imaging for biomedical applications due to important advantages such as lack of autofluorescence, weak photon absorption by blood and tissues, and reduced photon scattering coefficient. Therefore, contrary to the visible and NIR regions, tissues become translucent in the SWIR region. Nevertheless, the lack of bright and biocompatible probes is a key challenge that must be overcome to unlock the full potential of SWIR fluorescence. Although rare-earth-based core-shell nanocrystals appeared as promising SWIR probes, they suffer from limited photoluminescence quantum yield (PLQY). The lack of control over the atomic scale organization of such complex materials is one of the main barriers limiting their optical performance. Here, the growth of either homogeneous (α-NaYF<sub>4</sub>) or heterogeneous (CaF<sub>2</sub>) shell domains on optically-active α-NaYF<sub>4</sub>:Yb:Er (with and without Ce<sup>3+</sup>co-doping) core nanocrystals is reported. The atomic scale organization can be controlled by preventing cation intermixing only in heterogeneous core-shell nanocrystals with a dramatic impact on the PLQY. The latter reached 50% at 60 mW/cm<sup>2</sup>; one of the highest reported PLQY values for sub-15 nm nanocrystals. The most efficient nanocrystals were utilized for in vivo imaging above 1450 nm. | ||||
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Language | Wos | 001037058500022 | Publication Date | 2023-07-25 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 16.6 | Times cited | 1 | Open Access | OpenAccess |
Notes | D.H. would like to thank Dominique Ectors (Bruker AXS GmbH, Karlsruhe, Germany) for assistance and discussion on the PXRD data and TOPAS evaluations. The authors would like to acknowledge the financial support provided by the Helmholtz Association via: i) the Professorial Recruitment Initiative Funding (B.S.R.); ii) the Research Field Energy – Program Materials and Technologies for the Energy Transition – Topic 1 Photovoltaics (F.A.C., D.B., E.M., B.S.R., D.H.). This project received funding from the European Union’s Horizon 2020 innovation programme under grant agreement 823717. This work was supported by the European Research Council (grant 770887-PICOMETRICS to S.V.A. and Grant 815128-REALNANO to S.B.). The authors acknowledge financial support from the ResearchFoundation Flanders (FWO, Belgium) through project fundings (G.0346.21 N to S.V.A. and S.B.) and a postdoctoral grant (A.D.B.). The authors (B.A.A., O.T.B. and A.C.) acknowledge funding from the Helmholtz Zentrum München, the DFG-Emmy Noether program (BR 5355/2-1) and from the CZI Deep Tissue Imaging (DTI-0000000248). The authors (O.T.B. and D.H.) would like to thank the Helmholtz Imaging (ZT-I-PF-4-038-BENIGN). | Approved | Most recent IF: 16.6; 2023 IF: 12.124 | ||
Call Number | EMAT @ emat @c:irua:198158 | Serial | 8808 | ||
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Author | Lobato, I.; De Backer, A.; Van Aert, S. | ||||
Title | Real-time simulations of ADF STEM probe position-integrated scattering cross-sections for single element fcc crystals in zone axis orientation using a densely connected neural network | Type | A1 Journal article | ||
Year | 2023 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | 251 | Issue | Pages | 113769 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Quantification of annular dark field (ADF) scanning transmission electron microscopy (STEM) images in terms of composition or thickness often relies on probe-position integrated scattering cross sections (PPISCS). In order to compare experimental PPISCS with theoretically predicted ones, expensive simulations are needed for a given specimen, zone axis orientation, and a variety of microscope settings. The computation time of such simulations can be in the order of hours using a single GPU card. ADF STEM simulations can be efficiently parallelized using multiple GPUs, as the calculation of each pixel is independent of other pixels. However, most research groups do not have the necessary hardware, and, in the best-case scenario, the simulation time will only be reduced proportionally to the number of GPUs used. In this manuscript, we use a learning approach and present a densely connected neural network that is able to perform real-time ADF STEM PPISCS predictions as a function of atomic column thickness for most common face-centered cubic (fcc) crystals (i.e., Al, Cu, Pd, Ag, Pt, Au and Pb) along [100] and [111] zone axis orientations, root-mean-square displacements, and microscope parameters. The proposed architecture is parameter efficient and yields accurate predictions for the PPISCS values for a wide range of input parameters that are commonly used for aberration-corrected transmission electron microscopes. |
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Language | Wos | 001011617200001 | Publication Date | 2023-06-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 2.2 | Times cited | Open Access | OpenAccess | |
Notes | This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S. Van Aert). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G034621N and G0A7723N) and a postdoctoral grant to A. De Backer. S. Van Aert acknowledges funding from the University of Antwerp Research fund (BOF), Belgium. | Approved | Most recent IF: 2.2; 2023 IF: 2.843 | ||
Call Number | EMAT @ emat @c:irua:197275 | Serial | 8812 | ||
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Author | Şentürk, DG.; Yu, CP.; De Backer, A.; Van Aert, S. | ||||
Title | Atom counting from a combination of two ADF STEM images | Type | A1 Journal article | ||
Year | 2024 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | 255 | Issue | Pages | 113859 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | To understand the structure–property relationship of nanostructures, reliably quantifying parameters, such as the number of atoms along the projection direction, is important. Advanced statistical methodologies have made it possible to count the number of atoms for monotype crystalline nanoparticles from a single ADF STEM image. Recent developments enable one to simultaneously acquire multiple ADF STEM images. Here, we present an extended statistics-based method for atom counting from a combination of multiple statistically independent ADF STEM images reconstructed from non-overlapping annular detector collection regions which improves the accuracy and allows one to retrieve precise atom-counts, especially for images acquired with low electron doses and multiple element structures. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 001089064200001 | Publication Date | 2023-09-23 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.2 | Times cited | Open Access | OpenAccess | |
Notes | This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S. Van Aert). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G034621N, G0A7723N, and EOS 40007495) and a postdoctoral grant to A. De Backer. S. Van Aert acknowledges funding from the University of Antwerp Research fund (BOF). | Approved | Most recent IF: 2.2; 2024 IF: 2.843 | ||
Call Number | EMAT @ emat @c:irua:201008 | Serial | 8964 | ||
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Author | Şentürk, D.G.; De Backer, A.; Van Aert, S. | ||||
Title | Element specific atom counting for heterogeneous nanostructures: Combining multiple ADF STEM images for simultaneous thickness and composition determination | Type | A1 Journal Article | ||
Year | 2024 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | 259 | Issue | Pages | 113941 | |
Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
Abstract | In this paper, a methodology is presented to count the number of atoms in heterogeneous nanoparticles based on the combination of multiple annular dark field scanning transmission electron microscopy (ADF STEM) images. The different non-overlapping annular detector collection regions are selected based on the principles of optimal statistical experiment design for the atom-counting problem. To count the number of atoms, the total intensities of scattered electrons for each atomic column, the so-called scattering cross-sections, are simultaneously compared with simulated library values for the different detector regions by minimising the squared differences. The performance of the method is evaluated for simulated Ni@Pt and Au@Ag core-shell nanoparticles. Our approach turns out to be a dose efficient alternative for the investigation of beam-sensitive heterogeneous materials as compared to the combination of ADF STEM and energy dispersive X-ray spectroscopy. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | Publication Date | 2024-02-19 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record | |
Impact Factor | 2.2 | Times cited | Open Access | OpenAccess | |
Notes | This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S. Van Aert). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0346.21N, GOA7723N, and EOS 40007495) and a postdoctoral grant to A. De Backer. S. Van Aert acknowledges funding from the University of Antwerp Research fund (BOF). | Approved | Most recent IF: 2.2; 2024 IF: 2.843 | ||
Call Number | EMAT @ emat @c:irua:204353 | Serial | 8996 | ||
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Author | van den Broek, W.; Verbeeck, J.; de Backer, S.; Scheunders, P.; Schryvers, D. | ||||
Title | Acquisition of the EELS data cube by tomographic reconstruction | Type | A1 Journal article | ||
Year | 2006 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | 106 | Issue | 4/5 | Pages | 269-276 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab | ||||
Abstract | Energy filtered TEM, EFTEM, provides three-dimensional data, two spatial and one spectral dimension. We propose to acquire these data by measuring a series of images with a defocused energy filter. It will be shown that each image is a projection of the data on the detector and that reconstruction of the data out of a sufficient number of such projections using a tomographic reconstruction algorithm is possible. This technique uses only a fraction of the electron dose an energy filtered series (EFS) needs for the same spectral and spatial resolution and the same mean signal-to-noise ratio. (c) 2005 Elsevier B.V. All rights reserved. | ||||
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Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000236042300003 | Publication Date | 2005-11-30 | |
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ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 6 | Open Access | |
Notes | Approved | Most recent IF: 2.843; 2006 IF: 1.706 | |||
Call Number | UA @ lucian @ c:irua:56910UA @ admin @ c:irua:56910 | Serial | 55 | ||
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Author | Verhulst, S.L.; de Backer, J.; Van Gaal, L.; de Backer, W.; Desager, K. | ||||
Title | Adenotonsillectomy as first-line treatment for sleep-disordered breathing in obese children | Type | L1 Letter to the editor | ||
Year | 2008 | Publication | American journal of respiratory and critical care medicine | Abbreviated Journal | Am J Resp Crit Care |
Volume | 177 | Issue | 12 | Pages | 1399 |
Keywords | L1 Letter to the editor; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
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Publisher | Place of Publication | New York | Editor | ||
Language | Wos | Publication Date | 0000-00-00 | ||
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Series Volume | Series Issue | Edition | |||
ISSN | 1073-449x; 1535-4970 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.204 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 13.204; 2008 IF: 9.792 | |||
Call Number | UA @ lucian @ c:irua:68864 | Serial | 59 | ||
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Author | van Holsbeke, C.; de Backer, J.; Vos, W.; Verdonck, P.; van Ransbeeck, P.; Claessens, T.; Braem, M.; Vanderveken, O.; de Backer, W. | ||||
Title | Anatomical and functional changes in the upper airways of sleep apnea patients due to mandibular repositioning: a large scale study | Type | A1 Journal article | ||
Year | 2011 | Publication | Journal of biomechanics | Abbreviated Journal | J Biomech |
Volume | 44 | Issue | 3 | Pages | 442-449 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT); Vision lab; Laboratory Experimental Medicine and Pediatrics (LEMP); Translational Neurosciences (TNW) | ||||
Abstract | The obstructive sleep apnea-hypopnea syndrome (OSAHS) is a sleep related breathing disorder. A popular treatment is the use of a mandibular repositioning appliance (MRA) which advances the mandibula during the sleep and decreases the collapsibility of the upper airway. The success rate of such a device is, however, limited and very variable within a population of patients. Previous studies using computational fluid dynamics have shown that there is a decrease in upper airway resistance in patients who improve clinically due to an MRA. In this article, correlations between patient-specific anatomical and functional parameters are studied to examine how MRA induced biomechanical changes will have an impact on the upper airway resistance. Low-dose computed tomography (CT) scans are made from 143 patients suffering from OSAHS. A baseline scan and a scan after mandibular repositioning (MR) are performed in order to study variations in parameters. It is found that MR using a simulation bite is able to induce resistance changes by changing the pharyngeal lumen. The change in minimal cross-sectional area is the best parameter to predict the change in upper airway resistance. Looking at baseline values, the ideal patients for MR induced resistance decrease seem to be women with short airways, high initial resistance and no baseline occlusion. | ||||
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Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | 000287551000014 | Publication Date | 2010-10-23 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0021-9290; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.664 | Times cited | 23 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 2.664; 2011 IF: 2.434 | ||
Call Number | UA @ lucian @ c:irua:85305 | Serial | 112 | ||
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Author | Vinchurkar, S.; De Backer, L.; Vos, W.; Van Holsbeke, C.; de Backer, J.; de Backer, W. | ||||
Title | A case series on lung deposition analysis of inhaled medication using functional imaging based computational fluid dynamics in asthmatic patients : effect of upper airway morphology and comparison with in vivo data | Type | A1 Journal article | ||
Year | 2012 | Publication | Inhalation Toxicology | Abbreviated Journal | Inhal Toxicol |
Volume | 24 | Issue | 2 | Pages | 81-88 |
Keywords | A1 Journal article; Pharmacology. Therapy; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
Abstract | Context: Asthma affects 20 million Americans resulting in an economic burden of approximately $18 billion in the US alone (Allergies and Asthma Foundation 2000; National Center for Environmental Health (NCEH) 1999). Research studies based on differences in patient-specific airway morphology for asthma and the associated effect on deposition of inhaled aerosols are currently not available in the literature. Therefore, the role of morphological variations such as upper airway (extrathoracic) occlusion is not well documented. Objective: Functional imaging based computational fluid dynamics (CFD) of the respiratory airways for five asthmatic subjects is performed in this study using computed tomography (CT) based patient-specific airway models and boundary conditions. Methods: CT scans for 5 asthma patients were used to reconstruct 3D lung models using segmentation software. An averaged inhalation profile and patient-specific lobar flow distribution were used to perform the simulation. The simulations were used to obtain deposition for BDP/Formoterol (R) HFA pMDI in the patient-specific airway models. Results: The lung deposition obtained using CFD was in excellent agreement with available in vivo data using the same product. Specifically, CFD resulted in 30% lung deposition, whereas in vivo lung deposition was reported to be approximately 31%. Conclusion: It was concluded that a combination of patient-specific airway models and lobar boundary conditions can be used to obtain accurate lung deposition estimates. Lower lung deposition can be expected for patients with higher extrathoracic resistance. Novel respiratory drug delivery devices need to accommodate population subgroups based on these morphological and anatomical differences in addition to subject age. | ||||
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Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | 000299744800001 | Publication Date | 2012-01-20 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0895-8378;1091-7691; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.751 | Times cited | 36 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 1.751; 2012 IF: 1.894 | ||
Call Number | UA @ lucian @ c:irua:96238 | Serial | 286 | ||
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Author | Van Holsbeke, C.S.; Verhulst, S.L.; Vos, W.G.; de Backer, J.W.; Vinchurkar, S.C.; Verdonck, P.R.; van Doorn, J.W.D.; Nadjmi, N.; de Backer, W.A. | ||||
Title | Change in upper airway geometry between upright and supine position during tidal nasal breathing | Type | A1 Journal article | ||
Year | 2014 | Publication | Journal Of Aerosol Medicine And Pulmonary Drug Delivery | Abbreviated Journal | J Aerosol Med Pulm D |
Volume | 27 | Issue | 1 | Pages | 51-57 |
Keywords | A1 Journal article; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP); Translational Neurosciences (TNW) | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000331144500007 | Publication Date | 2013-03-19 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1941-2711;1941-2703; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.528 | Times cited | 16 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 2.528; 2014 IF: 2.798 | ||
Call Number | UA @ lucian @ c:irua:115759 | Serial | 308 | ||
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Author | de Backer, J.W.; Vos, W.G.; Germonpré, P.; Salgado, R.; Parizel, P.M.; de Backer, W. | ||||
Title | Clinical applications of image-based airway computational fluid dynamics: assessment of inhalation medication and endobronchial devices | Type | A3 Journal article | ||
Year | 2009 | Publication | Proceedings of the Society of Photo-optical Instrumentation Engineers | Abbreviated Journal | |
Volume | 7262 | Issue | Pages | 72621p,1-72621p,9 | |
Keywords | A3 Journal article; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
Abstract | Computational fluid dynamics (CFD) is a technique that is used increasingly in the biomedical field. Solving the flow equations numerically provides a convenient way to assess the efficiency of therapies and devices, ranging from cardiovascular stents and heart valves to hemodialysis workflows. Also in the respiratory field CFD has gained increasing interest, especially through the combination of three dimensional image reconstruction which results in highend patient-specific models. This paper provides an overview of clinical applications of CFD through image based modeling, resulting from recent studies performed in our center. We focused on two applications: assessment of the efficiency of inhalation medication and analysis of endobronchial valve placement. In the first application we assessed the mode of action of a novel bronchodilator in 10 treated patients and 4 controls. We assessed the local volume increase and resistance change based on the combination of imaging and CFD. We found a good correlation between the changes in volume and resistance coming from the CFD results and the clinical tests. In the second application we assessed the placement and effect of one way endobronchial valves on respiratory function in 6 patients. We found a strong patientspecific result of the therapy where in some patients the therapy resulted in complete atelectasis of the target lobe while in others the lobe remained inflated. We concluded from these applications that CFD can provide a better insight into clinically relevant therapies. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | Publication Date | 2009-02-27 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Additional Links | UA library record | ||
Impact Factor | Times cited | Open Access | |||
Notes | Approved | Most recent IF: NA | |||
Call Number | UA @ lucian @ c:irua:79497 | Serial | 374 | ||
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Author | de Backer, J.W.; Vos, W.G.; Devolder, A.; Verhulst, S.L.; Germonpré, P.; Wuyts, F.L.; Parizel, P.M.; de Backer, W. | ||||
Title | Computational fluid dynamics can detect changes in airway resistance in asthmatics after acute bronchodilation | Type | A1 Journal article | ||
Year | 2008 | Publication | Journal of biomechanics | Abbreviated Journal | J Biomech |
Volume | 41 | Issue | 1 | Pages | 106-113 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | 000253062100014 | Publication Date | 2007-08-15 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-9290; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.664 | Times cited | 53 | Open Access | |
Notes | Approved | Most recent IF: 2.664; 2008 IF: 2.784 | |||
Call Number | UA @ lucian @ c:irua:64859 | Serial | 456 | ||
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Author | Vos, W.; de Backer, J.; Devolder, A.; Vanderveken, O.; Verhulst, S.; Salgado, R.; Germonpré, P.; Partoens, B.; Wuyts, F.; Parizel, P.; de Backer, W. | ||||
Title | Correlation between severity of sleep apnea and upper airway morphology based on advanced anatomical and functional imaging | Type | A1 Journal article | ||
Year | 2007 | Publication | Journal of biomechanics | Abbreviated Journal | J Biomech |
Volume | 40 | Issue | 10 | Pages | 2207-2213 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP); Translational Neurosciences (TNW) | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | 000248468000011 | Publication Date | 2006-12-19 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-9290; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.664 | Times cited | 86 | Open Access | |
Notes | Approved | Most recent IF: 2.664; 2007 IF: 2.897 | |||
Call Number | UA @ lucian @ c:irua:62425 | Serial | 523 | ||
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Author | de Backer, J.; Vos, W.; Van Holsbeke, C.; Vinchurkar, S.; Claes, R.; Parizel, P.M.; de Backer, W. | ||||
Title | Effect of high-dose N-acetylcysteine on airway geometry, inflammation, and oxidative stress in COPD patients | Type | A1 Journal article | ||
Year | 2013 | Publication | International Journal Of Chronic Obstructive Pulmonary Disease | Abbreviated Journal | Int J Chronic Obstr |
Volume | 8 | Issue | Pages | 569-579 | |
Keywords | A1 Journal article; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
Abstract | Background: Previous studies have demonstrated the potential beneficial effect of N-acetylcysteine (NAC) in chronic obstructive pulmonary disease (COPD). However, the required dose and responder phenotype remain unclear. The current study investigated the effect of high-dose NAC on airway geometry, inflammation, and oxidative stress in COPD patients. Novel functional respiratory imaging methods combining multislice computed tomography images and computer-based flow simulations were used with high sensitivity for detecting changes induced by the therapy. Methods: Twelve patients with Global Initiative for Chronic Obstructive Lung Disease stage II COPD were randomized to receive NAC 1800 mg or placebo daily for 3 months and were then crossed over to the alternative treatment for a further 3 months. Results: Significant correlations were found between image-based resistance values and glutathione levels after treatment with NAC (P = 0.011) and glutathione peroxidase at baseline (P = 0.036). Image-based resistance values appeared to be a good predictor for glutathione peroxidase levels after NAC (P = 0.02), changes in glutathione peroxidase levels (P = 0.035), and reduction in lobar functional residual capacity levels (P = 0.00084). In the limited set of responders to NAC therapy, the changes in airway resistance were in the same order as changes induced by budesonide/formoterol. Conclusion: A combination of glutathione, glutathione peroxidase, and imaging parameters could potentially be used to phenotype COPD patients who would benefit from addition of NAC to their current therapy. The findings of this small pilot study need to be confirmed in a larger pivotal trial. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000327537300001 | Publication Date | 2013-11-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1178-2005; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.157 | Times cited | 21 | Open Access | |
Notes | ; JDB is a founder/shareholder of FluidDA NV, Kontich, Belgium. WV, SV, and CVH are employed by FluidDA NV, and WDB is the director of FluidDA NV. PMP and RC have no conflicts of interest to report. The study was supported by Zambon SpA, Bresso, Italy. ; | Approved | Most recent IF: 3.157; 2013 IF: NA | ||
Call Number | UA @ lucian @ c:irua:112799 | Serial | 813 | ||
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Author | de Backer, W.; Vos, W.; Van Holsbeke, C.; Vinchurkar, S.; Claes, R.; Hufkens, A.; Parizel, P.M.; Bedert, L.; de Backer, J. | ||||
Title | The effect of roflumilast in addition to LABA/LAMA/ICS treatment in COPD patients | Type | L1 Letter to the editor | ||
Year | 2014 | Publication | European Respiratory Journal | Abbreviated Journal | Eur Respir J |
Volume | 44 | Issue | 2 | Pages | 527-529 |
Keywords | L1 Letter to the editor; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
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Publisher | Place of Publication | Copenhagen | Editor | ||
Language | Wos | 000340017300029 | Publication Date | 2014-05-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0903-1936;1399-3003; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 10.569 | Times cited | 26 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 10.569; 2014 IF: 7.636 | ||
Call Number | UA @ lucian @ c:irua:117335 | Serial | 832 | ||
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Author | De Backer, L.; Vos, W.; Dieriks, B.; Daems, D.; Verhulst, S.; Vinchurkar, S.; Ides, K.; de Backer, J.; Germonpré, P.; de Backer, W. | ||||
Title | The effects of long-term noninvasive ventilation in hypercapnic COPD patients : a randomized controlled pilot study | Type | A1 Journal article | ||
Year | 2011 | Publication | International journal of chronic obstructive pulmonary disease | Abbreviated Journal | Int J Chronic Obstr |
Volume | 6 | Issue | Pages | 615-624 | |
Keywords | A1 Journal article; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
Abstract | Introduction: Noninvasive ventilation (NIV) is a well-established treatment for acute-on-chronic respiratory failure in hypercapnic COPD patients. Less is known about the effects of a long-term treatment with NIV in hypercapnic COPD patients and about the factors that may predict response in terms of improved oxygenation and lowered CO2 retention.Methods: In this study, we randomized 15 patients to a routine pharmacological treatment (n = 5, age 66 [standard deviation ± 6] years, FEV1 30.5 [±5.1] %pred, PaO2 65 [±6] mmHg, PaCO2 52.4 [±6.0] mmHg) or to a routine treatment and NIV (using the Synchrony BiPAP device [Respironics, Inc, Murrsville, PA]) (n = 10, age 65 [±7] years, FEV1 29.5 [±9.0] %pred, PaO2 59 [±13] mmHg, PaCO2 55.4 [±7.7] mmHg) for 6 months. We looked at arterial blood gasses, lung function parameters and performed a low-dose computed tomography of the thorax, which was later used for segmentation (providing lobe and airway volumes, iVlobe and iVaw) and post-processing with computer methods (providing airway resistance, iRaw) giving overall a functional image of the separate airways and lobes.Results: In both groups there was a nonsignificant change in FEV1 (NIV group 29.5 [9.0] to 38.5 [14.6] %pred, control group 30.5 [5.1] to 36.8 [8.7] mmHg). PaCO2 dropped significantly only in the NIV group (NIV: 55.4 [7.7] → 44.5 [4.70], P = 0.0076; control: 52.4 [6.0] → 47.6 [8.2], NS). Patients actively treated with NIV developed a more inhomogeneous redistribution of mass flow than control patients. Subsequent analysis indicated that in NIV-treated patients that improve their blood gases, mass flow was also redistributed towards areas with higher vessel density and less emphysema, indicating that flow was redistributed towards areas with better perfusion. There was a highly significant correlation between the % increase in mass flow towards lobes with a blood vessel density of >9% and the increase in PaO2. Improved ventilation–perfusion match and recruitment of previously occluded small airways can explain the improvement in blood gases.Conclusion: We can conclude that in hypercapnic COPD patients treated with long-term NIV over 6 months, a mass flow redistribution occurs, providing a better ventilation–perfusion match and hence better blood gases and lung function. Control patients improve homogeneously in iVaw and iRaw, without improvement in gas exchange since there is no improved ventilation/perfusion ratio or increased alveolar ventilation. These differences in response can be detected through functional imaging, which gives a more detailed report on regional lung volumes and resistances than classical lung function tests do. Possibly only patients with localized small airway disease are good candidates for long-term NIV treatment. To confirm this and to see if better arterial blood gases also lead to better health related quality of life and longer survival, we have to study a larger population. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000208709800066 | Publication Date | 2011-11-18 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1178-2005; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.157 | Times cited | 28 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 3.157; 2011 IF: NA | ||
Call Number | UA @ lucian @ c:irua:93164 | Serial | 866 | ||
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Author | Klingstedt, M.; Sundberg, M.; Eriksson, L.; Haigh, S.; Kirkland, A.; Grüner, D.; de Backer, A.; Van Aert, S.; Tarasaki, O. | ||||
Title | Exit wave reconstruction from focal series of HRTEM images, single crystal XRD and total energy studies on SbxWO3+y (x\sim0.11) | Type | A1 Journal article | ||
Year | 2012 | Publication | Zeitschrift für Kristallographie | Abbreviated Journal | Z Krist-Cryst Mater |
Volume | 227 | Issue | 6 | Pages | 341-349 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A new tungsten bronze in the SbWO system has been prepared in a solid state reaction from Sb2O3, WO3 and W metal powder. The average structure was determined by single crystal X-ray diffraction. SbxWO3+y (x ∼ 0.11) crystallizes in the orthorhombic space group Pm21n (no. 31), a = 27.8135(9) Å, b = 7.3659(2) Å and c = 3.8672(1) Å. The structure belongs to the (n)-ITB class of intergrowth tungsten bronzes. It contains slabs of hexagonal channels formed by six WO6 octahedra. These slabs are separated by three layers of WO6 octahedra that are arranged in a WO3-type fashion. The WO6 octahedra share all vertices to build up a three-dimensional framework. The hexagonal channels are filled with Sb atoms to ∼80% and additional O atoms. The atoms are shifted out of the center of the channels. Exit-wave reconstruction of focal series of high resolution-transmission-electron-microscope (HRTEM) images combined with statistical paramäeter estimation techniques allowed to study local ordering in the channels. Sb atoms in neighbouring channels tend to be displaced in the same direction, which is in agreement with total energy calculations on ordered structure models, but the ratio of the occupation of the two possible Sb sites varies from channel to channel. The structure of SbxWO3+y exhibits pronounced local modulations. | ||||
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Publisher | Place of Publication | München | Editor | ||
Language | Wos | 000307314200003 | Publication Date | 2012-06-06 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2194-4946; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.179 | Times cited | 4 | Open Access | |
Notes | Fwo; Esteem 026019 | Approved | Most recent IF: 3.179; 2012 IF: NA | ||
Call Number | UA @ lucian @ c:irua:101218 | Serial | 1131 | ||
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Author | de Backer, J.W.; Vos, W.G.; Gorlé, C.D.; Germonpré, P.; Partoens, B.; Wuyts, F.L.; Parizel, P.M.; de Backer, W. | ||||
Title | Flow analyses in the lower airways: patient-specific model and boundary conditions | Type | A1 Journal article | ||
Year | 2008 | Publication | Medical engineering and physics | Abbreviated Journal | Med Eng Phys |
Volume | 30 | Issue | 7 | Pages | 872-879 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
Abstract | Computational fluid dynamics (CFD) is increasingly applied in the respiratory domain. The ability to simulate the flow through a bifurcating tubular system has increased the insight into the internal flow dynamics and the particular characteristics of respiratory flows such as secondary motions and inertial effects. The next step in the evolution is to apply the technique to patient-specific cases, in order to provide more information about pathological airways. This study presents a patient-specific approach where both the geometry and the boundary conditions (BC) are based on individual imaging methods using computed tomography (CT). The internal flow distribution of a 73-year-old female suffering from chronic obstructive pulmonary disease (COPD) is assessed. The validation is performed through the comparison of lung ventilation with gamma scintigraphy. The results show that in order to obtain agreement within the accuracy limits of the gamma scintigraphy scan, both the patient-specific geometry and the BC (driving pressure) play a crucial role. A minimal invasive test (CT scan) supplied enough information to perform an accurate CFD analysis. In the end it was possible to capture the pathological features of the respiratory system using the imaging and computational fluid dynamics techniques. This brings the introduction of this new technique in the clinical practice one step closer. | ||||
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Publisher | Place of Publication | London | Editor | ||
Language | Wos | 000259768300009 | Publication Date | 2007-12-26 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1350-4533; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.819 | Times cited | 82 | Open Access | |
Notes | Approved | Most recent IF: 1.819; 2008 IF: 2.216 | |||
Call Number | UA @ lucian @ c:irua:71693 | Serial | 1224 | ||
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Author | de Backer, J.; Vanderveken, O.; Vos, W.; Devolder, A.; Verhulst, S.; Verbraecken, J. | ||||
Title | Functional imaging to predict treatment success of mandibular advancement devices in sleep-disordered breathing | Type | H3 Book chapter | ||
Year | 2008 | Publication | Abbreviated Journal | ||
Volume | Issue | Pages | 141-155 | ||
Keywords | H3 Book chapter; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP); Translational Neurosciences (TNW) | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Antwerpen | Editor | ||
Language | Wos | Publication Date | 0000-00-00 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Additional Links | UA library record | ||
Impact Factor | Times cited | Open Access | |||
Notes | Approved | Most recent IF: NA | |||
Call Number | UA @ lucian @ c:irua:72885 | Serial | 1298 | ||
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Author | de Backer, J.W.; Vanderveken, O.M.; Vos, W.G.; Devolder, A.; Verhulst, S.L.; Verbraecken, J.A.; Parizel, P.M.; Braem, M.J.; van de Heyning, P.H.; de Backer, W.A. | ||||
Title | Functional imaging using computational fluid dynamics to predict treatment success of mandibular advancement devices in sleep-disordered breathing | Type | A1 Journal article | ||
Year | 2007 | Publication | Journal of biomechanics | Abbreviated Journal | J Biomech |
Volume | 40 | Issue | 16 | Pages | 3708-3714 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP); Translational Neurosciences (TNW) | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | 000251845100020 | Publication Date | 2007-08-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-9290; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.664 | Times cited | 66 | Open Access | |
Notes | Approved | Most recent IF: 2.664; 2007 IF: 2.897 | |||
Call Number | UA @ lucian @ c:irua:64860 | Serial | 1299 | ||
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Author | De Backer, L.A.; Vos, W.G.; Salgado, R.; de Backer, J.W.; Devolder, A.; Verhulst, S.L.; Claes, R.; Germonpré, P.R.; de Backer, W.A. | ||||
Title | Functional imaging using computer methods to compare the effect of salbutamol and ipratropium bromide in patient-specific airway models of COPD | Type | A1 Journal article | ||
Year | 2011 | Publication | International journal of chronic obstructive pulmonary disease | Abbreviated Journal | Int J Chronic Obstr |
Volume | 6 | Issue | Pages | 637-646 | |
Keywords | A1 Journal article; Condensed Matter Theory (CMT); Vision lab; Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
Abstract | Background: Salbutamol and ipratropium bromide improve lung function in patients with chronic obstructive pulmonary disease (COPD). However, their bronchodilating effect has not yet been compared in the central and distal airways. Functional imaging using computational fluid dynamics offers the possibility of making such a comparison. The objective of this study was to assess the effects of salbutamol and ipratropium bromide on the geometry and computational fluid dynamics-based resistance of the central and distal airways.Methods: Five patients with Global Initiative for Chronic Obstructive Lung Disease Stage III COPD were randomized to a single dose of salbutamol or ipratropium bromide in a crossover manner with a 1-week interval between treatments. Patients underwent lung function testing and a multislice computed tomography scan of the thorax that was used for functional imaging. Two hours after dosing, the patients again underwent lung function tests and repeat computed tomography.Results: Lung function parameters, including forced expiratory volume in 1 second, vital capacity, overall airway resistance, and specific airway resistance, changed significantly after administration of each product. On functional imaging, the bronchodilating effect was greater in the distal airways, with a corresponding drop in airway resistance, compared with the central airways. Salbutamol and ipratropium bromide were equally effective at first glance when looking at lung function tests, but when viewed in more detail with functional imaging, hyporesponsiveness could be shown for salbutamol in one patient. Salbutamol was more effective in the other patients.Conclusion: This pilot study gives an innovative insight into the modes of action of salbutamol and ipratropium bromide in patients with COPD, using the new techniques of functional imaging and computational fluid dynamics. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000208709800068 | Publication Date | 2011-11-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1178-2005; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.157 | Times cited | 25 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 3.157; 2011 IF: NA | ||
Call Number | UA @ lucian @ c:irua:93165 | Serial | 1300 | ||
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Author | Van Holsbeke, C.; Vos, W.; van Hoorenbeeck, K.; Boudewyns, A.; Salgado, R.; Verdonck, P.R.; Ramet, J.; de Backer, J.; De Backer, W.; Verhulst, S.L. | ||||
Title | Functional respiratory imaging as a tool to assess upper airway patency in children with obstructive sleep apnea | Type | A1 Journal article | ||
Year | 2013 | Publication | Sleep Medicine | Abbreviated Journal | Sleep Med |
Volume | 14 | Issue | 5 | Pages | 433-439 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
Abstract | Objective: We aim to investigate if anatomical and functional properties of the upper airway using computerized 3D models derived from computed tomography (CT) scans better predict obstructive sleep apnea (OSA) severity than standard clinical markers. Methods: Consecutive children with suspected OSA underwent polysomnography, clinical assessment of upper airway patency, and a CT scan while awake. A three-dimensional (3D) reconstruction of the pharyngeal airway was built from these images, and computational fluid dynamics modeling of low inspiratory flow was performed using open-source software. Results: Thirty-three children were included (23 boys; mean age, was 6.0 +/- 3.2 y). OSA was diagnosed in 23 patients. Children with OSA had a significantly lower volume of the overlap region between tonsils and the adenoids (median volume, 1408 mm compared to 2173 mm; p = 0.04), a lower mean cross-sectional area at this location (median volume, 69.3 mm(2) compared to 114.3 mm(2); p = 0.04), and a lower minimal cross-sectional area (median volume, 17.9 mm(2) compared to 25.9 mm(2); p = 0.05). Various significant correlations were found between several imaging parameters and the severity of OSA, most pronounced for upper airway conductance (r = -0.46) (p < 0.01) for correlation between upper airway conductance and the apnea-hypopnea index. No differences or significant correlations were observed with clinical parameters of upper airway patency. Preliminary data after treatment showed that none of the patients with residual OSA had their smallest cross-sectional area located in segment 3, and this frequency was significantly lower than in their peers whose sleep study normalized (64%; p = 0.05). Conclusion: Functional imaging parameters are highly correlated with OSA severity and are a more powerful correlate than clinical scores of upper airway patency. Preliminary data also showed that we could identify differences in the upper airway of those subjects who did not benefit from a local upper airway treatment. (c) 2013 Elsevier B.V. All rights reserved. | ||||
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Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000318612100009 | Publication Date | 2013-03-07 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1389-9457; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.391 | Times cited | 18 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 3.391; 2013 IF: 3.100 | ||
Call Number | UA @ lucian @ c:irua:109015 | Serial | 1302 | ||
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Author | Van Holsbeke, C.S.; Leemans, G.; Vos, W.G.; de Backer, J.W.; Vinchurkar, S.C.; Geldof, M.; Verdonck, P.R.; Parizel, P.M.; van Schil, P.E.; de Backer, W.A. | ||||
Title | Functional Respiratory Imaging as a tool to personalize respiratory treatment in subjects with unilateral diaphragmatic paralysis | Type | A1 Journal article | ||
Year | 2013 | Publication | Respiratory care | Abbreviated Journal | Resp Care |
Volume | Issue | Pages | 1-20 | ||
Keywords | A1 Journal article; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
Abstract | In two subjects with a unilateral diaphragmatic paralysis and complaints of dyspnea, a completely different treatment approach was chosen despite similar anatomical and physiological abnormalities. These decisions were supported by the results generated by Functional Respiratory Imaging (FRI). FRI was able to generate functional information with respect to lobar ventilation and local drug deposition. In one subject, it was found that some lobes were poorly ventilated and drug deposition simulation showed that some regions were undertreated. This subject underwent a diaphragm plication to restore the ventilation. In the other subject, it was found that all lobes were still ventilated. A conservative approach with regular follow-up was chosen to wait for spontaneous recovery of the diaphragmatic function. Both subjects improved subjectively and objectively. These cases demonstrate how novel medical imaging techniques such as FRI can be used to personalize respiratory treatment in subjects with unilateral diaphragmatic paralysis. | ||||
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Publisher | Place of Publication | Dallas, Tex. | Editor | ||
Language | Wos | 000349200100024 | Publication Date | 2013-12-11 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0020-1324;1943-3654; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.733 | Times cited | 5 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 1.733; 2013 IF: 1.840 | ||
Call Number | UA @ lucian @ c:irua:112982 | Serial | 1303 | ||
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Author | de Backer, A.; Van Aert, S.; van Dyck, D. | ||||
Title | High precision measurements of atom column positions using model-based exit wave reconstruction | Type | A1 Journal article | ||
Year | 2011 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | 111 | Issue | 9/10 | Pages | 1475-1482 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab | ||||
Abstract | In this paper, it has been investigated how to measure atom column positions as accurately and precisely as possible using a focal series of images. In theory, it is expected that the precision would considerably improve using a maximum likelihood estimator based on the full series of focal images. As such, the theoretical lower bound on the variances of the unknown atom column positions can be attained. However, this approach is numerically demanding. Therefore, maximum likelihood estimation has been compared with the results obtained by fitting a model to a reconstructed exit wave rather than to the full series of focal images. Hence, a real space model-based exit wave reconstruction technique based on the channelling theory is introduced. Simulations show that the reconstructed complex exit wave contains the same amount of information concerning the atom column positions as the full series of focal images. Only for thin samples, which act as weak phase objects, this information can be retrieved from the phase of the reconstructed complex exit wave. | ||||
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Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000300461200004 | Publication Date | 2011-07-28 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 8 | Open Access | |
Notes | Fwo | Approved | Most recent IF: 2.843; 2011 IF: 2.471 | ||
Call Number | UA @ lucian @ c:irua:91879 | Serial | 1438 | ||
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Author | Vos, W.; de Backer, J.; Poli, G.; De Volder, A.; Ghys, L.; Van Holsbeke, C.; Vinchurkar, S.; De Backer, L.; de Backer, W. | ||||
Title | Novel functional imaging of changes in small airways of patients treated with extrafine beclomethasone/formoterol | Type | A1 Journal article | ||
Year | 2013 | Publication | Respiration | Abbreviated Journal | Respiration |
Volume | 86 | Issue | 5 | Pages | 393-401 |
Keywords | A1 Journal article; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
Abstract | Background: Inhaled formulations using extrafine particles of long-acting beta(2)-agonists and corticosteroids were developed to optimize asthma treatment. Findings that these combinations reach and treat smaller airways more effectively are predominantly based on general non-specific outcomes with little information on regional characteristics. Objectives: This study aims to assess long-term effects of extrafine beclomethasone/formoterol on small airways of asthmatic patients using novel functional imaging methods. Methods: Twenty-four stable asthma patients were subdivided into three groups (steroid naive, n = 7; partially controlled, n = 6; well controlled, n = 11). Current treatment was switched to a fixed combination of extrafine beclomethasone/formoterol (Foster (R); Chiesi Pharmaceuticals, Parma, Italy). Patients underwent lung function evaluation and thorax high-resolution computerized tomography (HRCT) scan. Local airway resistance was obtained from computational fluid dynamics (CFD). Results: After 6 months, the entire population showed improvement in pre-bronchodilation imaging parameters, including small airway volume (p = 0.0007), resistance (p = 0.011), and asthma control score (p = 0.016). Changes in small airway volume correlated with changes in asthma control score (p = 0.004). Forced expiratory volume in 1 s (p = 0.044) and exhaled nitric oxide (p = 0.040) also improved. Functional imaging provided more detail and clinical relevance compared to lung function tests, especially in the well-controlled group where only functional imaging parameters showed significant improvement, while the correlation with asthma control score remained. Conclusions: Extrafine beclomethasone/formoterol results in a significant reduction of small airway obstruction, detectable by functional imaging (HRCT/CFD). Changes in imaging parameters correlated significantly with clinically relevant improvements. This indicates that functional imaging is a useful tool for sensitive assessment of changes in the respiratory system after asthma treatment. Copyright (C) 2013 S. Karger AG, Basel | ||||
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Publisher | Place of Publication | Basel | Editor | ||
Language | Wos | 000329046200006 | Publication Date | 2013-04-12 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 1423-0356;0025-7931; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.772 | Times cited | 30 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 2.772; 2013 IF: 2.924 | ||
Call Number | UA @ lucian @ c:irua:113762 | Serial | 2376 | ||
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Author | de Backer, J.W.; Vos, W.G.; Verhulst, S.L.; de Backer, W. | ||||
Title | Novel imaging techniques using computer methods for the evaluation of the upper airway in patients with sleep-disordered breathing: a comprehensive review | Type | A1 Journal article | ||
Year | 2008 | Publication | Sleep medicine reviews | Abbreviated Journal | Sleep Med Rev |
Volume | 12 | Issue | 6 | Pages | 437-447 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
Abstract | Patients with sleep related breathing disorders (SRBD) can be treated with nasal continuous positive airway pressure (nCPAP) or with several upper airway (UA) interventions. While nCPAP is almost always effective when clinically well tolerated, the therapeutic outcome of UA surgery and UA devices is difficult to predict. The improvement of our capability to perform the latter predictions more accurately is of great clinical importance since it will prevent patients to be treated with ineffective, sometimes irreversible, techniques. In this review we describe the importance of new imaging methods in this respect. We first refer to the most important pathophysiological mechanisms known so far to play a role in SRBD, indicating that functional imaging could elucidate these mechanisms in a patient specific manner. Then we describe the new technologies that make UA imaging more functional referring to the data as they are presently available. Finally we summarise the studies that do indicate that the use of functional imaging of the UA in SRBD patients may significantly help to predict the clinical outcome after UA interventions. | ||||
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Publisher | Place of Publication | New York | Editor | ||
Language | Wos | 000261904500003 | Publication Date | 2008-10-16 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 1087-0792; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.958 | Times cited | 33 | Open Access | |
Notes | Approved | Most recent IF: 8.958; 2008 IF: 6.143 | |||
Call Number | UA @ lucian @ c:irua:71640 | Serial | 2378 | ||
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Author | Horemans, B.; Van Holsbeke, C.; Vos, W.; Darchuk, L.; Novakovic, V.; Fontan, A.C.; de Backer, J.; van Grieken, R.; de Backer, W.; De Wael, K. | ||||
Title | Particle deposition in airways of chronic respiratory patients exposed to an urban aerosol | Type | A1 Journal article | ||
Year | 2012 | Publication | Environmental science and technology | Abbreviated Journal | Environ Sci Technol |
Volume | 46 | Issue | 21 | Pages | 12162-12169 |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
Abstract | Urban atmospheres in modern cities carry characteristic mixtures of particulate pollution which are potentially aggravating for chronic respiratory patients (CRP). Although air quality surveys can be detailed, the obtained information is not always useful to evaluate human health effects. This paper presents a novel approach to estimate particle deposition rates in airways of CRP, based on real air pollution data. By combining computational fluid dynamics with physical-chemical characteristics of particulate pollution, deposition rates are estimated for particles of different toxicological relevance, that is, minerals, iron oxides, sea salts, ammonium salts, and carbonaceous particles. Also, it enables some qualitative evaluation of the spatial, temporal, and patient specific effects on the particle dose upon exposure to the urban atmosphere. Results show how heavy traffic conditions increases the deposition of anthropogenic particles in the trachea and lungs of respiratory patients (here, +0.28 and +1.5 μg·h1, respectively). In addition, local and synoptic meteorological conditions were found to have a strong effect on the overall dose. However, the pathology and age of the patient was found to be more crucial, with highest deposition rates for toxic particles in adults with a mild anomaly, followed by mild asthmatic children and adults with severe respiratory dysfunctions (7, 5, and 3 μg·h1, respectively). | ||||
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Publisher | Place of Publication | Easton, Pa | Editor | ||
Language | Wos | 000310665000082 | Publication Date | 2012-10-04 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0013-936X;1520-5851; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.198 | Times cited | 5 | Open Access | |
Notes | ; We are grateful for the financial support of n.v. Vooruitzicht. Furthermore, co-workers at the environmental analysis research group are acknowledged for their help in the fieldwork. ; | Approved | Most recent IF: 6.198; 2012 IF: 5.257 | ||
Call Number | UA @ lucian @ c:irua:101411 | Serial | 2557 | ||
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