Institut für Medizintechnik und Medizininformatik

Dauerhafte URI für die Sammlunghttps://irf.fhnw.ch/handle/11654/23

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  • Vorschaubild
    Publikation
    Maturation of the human immunoglobulin heavy chain repertoire with age
    (Frontiers Research Foundation, 06.08.2020) Ghraichy, Marie; Galson, Jacob D.; Kovaltsuk, Aleksandr; von Niederhäusern, Valentin; Pachlopnik Schmid, Jana; Recher, Mike; Jauch, Annaïse J.; Miho, Enkelejda; Kelly, Dominic F.; Deane, Charlotte M.; Trück, Johannes
    B cells play a central role in adaptive immune processes, mainly through the production of antibodies. The maturation of the B cell system with age is poorly studied. We extensively investigated age-related alterations of naïve and antigen-experienced immunoglobulin heavy chain (IgH) repertoires. The most significant changes were observed in the first 10 years of life, and were characterized by altered immunoglobulin gene usage and an increased frequency of mutated antibodies structurally diverging from their germline precursors. Older age was associated with an increased usage of downstream IgH constant region genes and fewer antibodies with self-reactive properties. As mutations accumulated with age, the frequency of germline-encoded self-reactive antibodies decreased, indicating a possible beneficial role of self-reactive B cells in the developing immune system. Our results suggest a continuous process of change through childhood across a broad range of parameters characterizing IgH repertoires and stress the importance of using well-selected, age-appropriate controls in IgH studies.
    01A - Beitrag in wissenschaftlicher Zeitschrift
  • Vorschaubild
    Publikation
    A survey of practice patterns for real-time intrafractional motion-management in particle therapy
    (Elsevier, 26.04.2023) Zhang, Ye; Trnkova, Petra; Toshito, Toshiyuki; Heijmen, Ben; Richter, Christian; Aznar, Marianne; Albertini, Francesca; Bolsi, Alexandra; Daartz, Juliane; Bertholet, Jenny; Knopf, Antje
    01A - Beitrag in wissenschaftlicher Zeitschrift
  • Vorschaubild
    Publikation
    Increased construct stiffness with meniscal repair sutures and devices increases the risk of cheese-wiring during biomechanical load-to-failure testing
    (SAGE, 15.06.2021) Müller, Sebastian; Schwenk, Tanja; de Wild, Michael; Dimitrou, Dimitris; Rosso, Claudio
    Background: Cheese-wiring, the suture that cuts through the meniscus, is a well-known issue in meniscal repair. So far, contributing factors are neither fully understood nor sufficiently studied. Hypothesis/purpose: To investigate whether the construct stiffness of repair sutures and devices correlates with suture cut-through (cheese-wiring) during load-to-failure testing. Study design: Controlled laboratory study. Methods: In 131 porcine menisci, longitudinal bucket-handle tears were repaired using either inside-out sutures (n = 66; No. 0 Ultrabraid, 2-0 Orthocord, 2-0 FiberWire, and 2-0 Ethibond) or all-inside devices (n = 65; FastFix360, Omnispan, and Meniscal Cinch). After cyclic loading, load-to-failure testing was performed. The mode of failure and construct stiffness were recorded. A receiver operating characteristic curve analysis was performed to define the optimal stiffness threshold for predicting meniscal repair failure by cheese-wiring. The 2-tailed t test and analysis of variance were used to test significance. Results: Loss of suture fixation was the most common mode of failure in all specimens (58%), except for the Omnispan, which failed most commonly because of anchor pull-through. The Omnispan demonstrated the highest construct stiffness (30.8 ± 3.5 N/mm), whereas the Meniscal Cinch (18.0 ± 8.8 N/mm) and Ethibond (19.4 ± 7.8 N/mm) demonstrated the lowest construct stiffness. The Omnispan showed significantly higher stiffness compared with the Meniscal Cinch (P < .001) and Ethibond (P = .02), whereas the stiffness of the Meniscal Cinch was significantly lower compared with that of the FiberWire (P = .01), Ultrabraid (P = .04), and FastFix360 (P = .03). While meniscal repair with a high construct stiffness more often failed by cheese-wiring, meniscal repair with a lower stiffness failed by loss of suture fixation, knot slippage, or anchor pull-through. Meniscal repair with a stiffness >26.5 N/mm had a 3.6 times higher risk of failure due to cheese-wiring during load-to-failure testing (95% CI, 1.4-8.2; P < .0001). Conclusion: Meniscal repair using inside-out sutures and all-inside devices with a higher construct stiffness (>26.5 N/mm) was more likely to fail through suture cut-through (cheese-wiring) than that with a lower stiffness (≤26.5 N/mm). Clinical relevance: This is the first study investigating the impact of construct stiffness on meniscal repair failure by suture cut-through (cheese-wiring).
    01A - Beitrag in wissenschaftlicher Zeitschrift
  • Vorschaubild
    Publikation
    Clinical necessity of multi-image based (4DMIB) optimization for targets affected by respiratory motion and treated with scanned particle therapy – A comprehensive review
    (Elsevier, 02/2022) Czerska, Katarzyna; Fracchiolla, Francesco; Graeff, Christian; Molinelli, Silvia; Rinaldi, Ilaria; Rucincki, Antoni; Sterpin, Edmond; Stützer, Kristin; Trnkova, Petra; Zhang, Ye; Chang, Joe Y; Giap, Huan; Liu, Wei; Schild, Steven E; Simone, Charles B.; Lomax, Antony J; Meijers, Arturs; Knopf, Antje
    4D multi-image-based (4D MIB) optimization is a form of robust optimization where different uncertainty scenarios, due to anatomy variations, are considered via multiple image sets (e.g., 4DCT). In this review, we focused on providing an overview of different 4DMIB optimization implementations, introduced var- ious frameworks to evaluate the robustness of scanned particle therapy affected by breathing motion and summarized the existing evidence on the necessity of using 4DMIB optimization clinically. Expected potential benefits of 4DMIB optimization include more robust and/or interplay-effect-resistant doses for the target volume and organs-at-risk for indications affected by anatomical variations (e.g., breathing, peristalsis, etc.). Although considerable literature is available on the research and technical aspects of 4DMIB, clinical studies are rare and often contain methodological limitations, such as, limited patient number, motion amplitude, motion and delivery time structure considerations, number of repeat CTs, etc. Therefore, the data are not conclusive. In addition, multiple studies have found that robust 3D opti- mized plans result in dose distributions within the set clinical tolerances and, therefore, are suitable for a treatment of moving targets with scanned particle therapy. We, therefore, consider the clinical necessity of 4D MIB optimization, when treating moving targets with scanned particle therapy, as still to be demonstrated.
    01A - Beitrag in wissenschaftlicher Zeitschrift
  • Publikation
    Magnetic field measurements of portable electronic devices. The risk inside pockets for patients with cardiovascular implantable devices
    (American Heart Association, 15.03.2022) Féry, Corentin; Desombre, Adrien; Quirin, Thomas; Badertscher, Patrick; Sticherling, Christian; Knecht, Sven; Pascal, Joris
    01A - Beitrag in wissenschaftlicher Zeitschrift
  • Publikation
    A novel assistive method for rigidity evaluation during deep brain stimulation surgery using acceleration sensors
    (American Association of Neurological Surgeons, 09/2017) Shah, Ashesh; Coste, Jérôme; Lemaire, Jean-Jaques; Schkommodau, Erik; Taub, Ethan; Guzman, Raphael; Hemm-Ode, Simone
    01A - Beitrag in wissenschaftlicher Zeitschrift
  • Publikation
    Patient-specific electric field simulations and acceleration measurements for objective analysis of intraoperative stimulation tests in the thalamus
    (Frontiers, 25.11.2016) Hemm-Ode, Simone; Pison, Daniela; Alonso, Fabiola; Shah, Ashesh; Coste, Jérôme; Lemaire, Jean-Jaques; Wårdell, Karin
    01A - Beitrag in wissenschaftlicher Zeitschrift
  • Publikation
    Erratum to “Lamb waves and adaptive beamforming for aberration correction in medical ultrasound imaging”
    (IEEE, 02/2021) Mozaffarzadeh, Moein; Minonzio, Claudio; De jong, Nico; Verweij, Martin; Hemm-Ode, Simone; Renaud, Guillaume; Daeichin, Verya
    In the above article [1] , we mentioned that the superposition of the different symmetric (S) modes in the frequency wavenumber (f-k) domain results in a high-intensity region where its slope corresponds to the longitudinal wave speed in the slab. However, we have recently understood that this high intensity region belongs to the propagation of a wave called lateral wave or head wave [2] – [5] . It is generated if the longitudinal sound speed of the aberrator (i.e., the PVC slab) is larger than that of water and if the incident wavefront is curved. When the incidence angle at the interface between water and PVC is near the critical angle, the refracted wave in PVC reradiates a small part of its energy into the fluid (i.e., the head wave). As discussed in [4] , if the thickness of the waveguide is larger than the wavelength, the first arriving signal is the head wave. This is also the case in our study [1] where the ultrasound wavelength of a compressional wave in PVC was close to 1 mm, and a PVC slab with a thickness of 8 mm was used.
    01A - Beitrag in wissenschaftlicher Zeitschrift
  • Publikation
    Investigation of structural resorption behavior of biphasic bioceramics with help of gravimetry, μCT, SEM, and XRD
    (07.05.2015) de Wild, Michael; Molenberg, Aart; Amacher, Fabienne; Chris, Bradbury
    Resorbable bone substitute materials are widely used for bone augmentation after tumor resection, parallel to implant placement, or in critical size bone defects. In this study, the structural dissolution of a biphasic calcium phosphate bone substitute material with a hydroxyapatite (HA)/tricalcium phosphate (ß-TCP) ratio of 60/40 was investigated by repeatedly placing porous blocks in EDTA solution at 37°C. At several time points, the blocks were investigated by SEM, µCT, and gravimetry. It was found that always complete 2–3 µm sized grains were removed from the structure and that the ß-TCP is dissolved more rapidly. This selective dissolution of the ß-TCP grains was confirmed by XRD measurements. The blocks were eroded from the outside toward the center. The structure remained mechanically stable because the central part showed a delayed degradation and because the slower dissolving HA grains preserved the integrity of the structure.
    01A - Beitrag in wissenschaftlicher Zeitschrift