{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,11]],"date-time":"2026-01-11T06:32:30Z","timestamp":1768113150137,"version":"3.49.0"},"reference-count":50,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2023,2,18]],"date-time":"2023-02-18T00:00:00Z","timestamp":1676678400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"European Training Network within the framework of Horizon 2020 Marie Sk\u0142odowska-Curie Action (MSCA)","doi-asserted-by":"publisher","award":["811226"],"award-info":[{"award-number":["811226"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Magnesium (Mg) alloys possess unique properties that make them ideal for use as biodegradable implants in clinical applications. However, reports on the in vivo assessment of these alloys are insufficient. Thus, monitoring the degradation of Mg and its alloys in vivo is challenging due to the dynamic process of implant degradation and tissue regeneration. Most current works focus on structural remodeling, but functional assessment is crucial in providing information about physiological changes in tissues, which can be used as an early indicator of healing. Here, we report continuous wave near-infrared spectroscopy (CW NIRS), a non-invasive technique that is potentially helpful in assessing the implant\u2013tissue dynamic interface in a rodent model. The purpose of this study was to investigate the effects on hemoglobin changes and tissue oxygen saturation (StO2) after the implantation of Mg-alloy (WE43) and titanium (Ti) implants in rats\u2019 femurs using a multiwavelength optical probe. Additionally, the effect of changes in the skin on these parameters was evaluated. Lastly, combining NIRS with photoacoustic (PA) imaging provides a more reliable assessment of tissue parameters, which is further correlated with principal component analysis.<\/jats:p>","DOI":"10.3390\/s23042297","type":"journal-article","created":{"date-parts":[[2023,2,20]],"date-time":"2023-02-20T02:29:08Z","timestamp":1676860148000},"page":"2297","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Near-Infrared Spectroscopy for the In Vivo Monitoring of Biodegradable Implants in Rats"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3499-2218","authenticated-orcid":false,"given":"Hafiz Wajahat","family":"Hassan","sequence":"first","affiliation":[{"name":"Faculty of Technology, Art and Design, Department of Mechanical, Electronic and Chemical Engineering, Oslo Metropolitan University, 0130 Oslo, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4305-8216","authenticated-orcid":false,"given":"Eduarda","family":"Mota-Silva","sequence":"additional","affiliation":[{"name":"Institute of Clinical Physiology, National Research Council (IFC-CNR), 56124 Pisa, Italy"},{"name":"Institute of Life Sciences, Sant\u2019Anna School of Advanced Studies, 56127 Pisa, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6912-5053","authenticated-orcid":false,"given":"Valeria","family":"Grasso","sequence":"additional","affiliation":[{"name":"FUJIFILM VisualSonics, 1114 AB Amsterdam, The Netherlands"},{"name":"Faculty of Engineering, Institute for Materials Science, Christian-Albrecht University of Kiel, D-24143 Kiel, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Leon","family":"Riehakainen","sequence":"additional","affiliation":[{"name":"Institute of Clinical Physiology, National Research Council (IFC-CNR), 56124 Pisa, Italy"},{"name":"Institute of Life Sciences, Sant\u2019Anna School of Advanced Studies, 56127 Pisa, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8389-5596","authenticated-orcid":false,"given":"Jithin","family":"Jose","sequence":"additional","affiliation":[{"name":"FUJIFILM VisualSonics, 1114 AB Amsterdam, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3293-9616","authenticated-orcid":false,"given":"Luca","family":"Menichetti","sequence":"additional","affiliation":[{"name":"Institute of Clinical Physiology, National Research Council (IFC-CNR), 56124 Pisa, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7664-5513","authenticated-orcid":false,"given":"Peyman","family":"Mirtaheri","sequence":"additional","affiliation":[{"name":"Faculty of Technology, Art and Design, Department of Mechanical, Electronic and Chemical Engineering, Oslo Metropolitan University, 0130 Oslo, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"309","DOI":"10.1016\/j.jcms.2015.12.009","article-title":"In vivo degradation of magnesium plate\/screw osteosynthesis implant systems: Soft and hard tissue response in a calvarial model in miniature pigs","volume":"44","author":"Schaller","year":"2016","journal-title":"J. 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