{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,12]],"date-time":"2026-09-12T00:54:44Z","timestamp":1789174484144,"version":"build-2803163510"},"reference-count":37,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,9,5]],"date-time":"2025-09-05T00:00:00Z","timestamp":1757030400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"the European Union (Horizon Framework)","doi-asserted-by":"publisher","award":["101092518"],"award-info":[{"award-number":["101092518"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biosensors"],"abstract":"<jats:p>A novel endoscopic palpation tool (EPT), designed for tactile and stiffness sensing using fiber Bragg gratings (FBGs) was evaluated in a surgical environment for intraoperative safety and effectiveness. The EPT consisted of four FBGs arranged in a cross pattern and embedded within an elastic, hollow, silicone hemispherical dome designed to deform upon contact with soft tissue. The EPT was employed to scan both in vivo and ex vivo tissue samples. Monitoring of porcine vital signs during minimally invasive and open surgical procedures showed no significant changes during use of the EPT. Perioperative blood tests including inflammatory markers and liver and renal function studies were unremarkable. Histopathological analyses of tissues involved (liver, spleen, bowel, and abdominal wall) showed no evidence of inflammation, necrosis, or tissue damage, confirming the device\u2019s biocompatibility. To the best of our knowledge, this is the first study reporting in vivo stiffness measurements using an FBG-based EPT. The probe successfully distinguished between soft and hard tissue regions\u2019 relative stiffness. Furthermore, successive measurements on liver samples demonstrated the device\u2019s ability to generate stiffness maps, enabling clear visualization of spatial variation in tissue stiffness.<\/jats:p>","DOI":"10.3390\/bios15090581","type":"journal-article","created":{"date-parts":[[2025,9,5]],"date-time":"2025-09-05T12:18:18Z","timestamp":1757074698000},"page":"581","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["In Vivo Study on the Safe Use of a Novel Intraoperative Sensing Tool for Tissue Stiffness Assessment in Endoscopic Surgery"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8429-2888","authenticated-orcid":false,"given":"Georgios","family":"Violakis","sequence":"first","affiliation":[{"name":"Department of Electrical and Computer Engineering, School of Engineering, Hellenic Mediterranean University, 71004 Heraklion, Greece"},{"name":"Componous P.C., 11 Kontopoulou Street, 53100 Florina, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7855-1721","authenticated-orcid":false,"given":"Pantelis","family":"Antonakis","sequence":"additional","affiliation":[{"name":"2nd Department of Surgery, Aretaieion University Hospital, National and Kapodistrian University of Athens (NKUA), 11528 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emmanouil","family":"Kritsotakis","sequence":"additional","affiliation":[{"name":"2nd Department of Surgery, Aretaieion University Hospital, National and Kapodistrian University of Athens (NKUA), 11528 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Theodoros","family":"Kozonis","sequence":"additional","affiliation":[{"name":"2nd Department of Surgery, Aretaieion University Hospital, National and Kapodistrian University of Athens (NKUA), 11528 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3079-6180","authenticated-orcid":false,"given":"Leonidas","family":"Chardalias","sequence":"additional","affiliation":[{"name":"2nd Department of Surgery, Aretaieion University Hospital, National and Kapodistrian University of Athens (NKUA), 11528 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Apostolos","family":"Papalois","sequence":"additional","affiliation":[{"name":"2nd Department of Surgery, Aretaieion University Hospital, National and Kapodistrian University of Athens (NKUA), 11528 Athens, Greece"},{"name":"Laboratory of Experimental Surgery, Aretaieion University Hospital, National and Kapodistrian University of Athens (NKUA), 11528 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Georgios","family":"Agrogiannis","sequence":"additional","affiliation":[{"name":"1st Department of Pathology, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-7003-4791","authenticated-orcid":false,"given":"Effrosyni","family":"Kampouroglou","sequence":"additional","affiliation":[{"name":"2nd Department of Surgery, Aretaieion University Hospital, National and Kapodistrian University of Athens (NKUA), 11528 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nikolaos","family":"Vardakis","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, School of Engineering, Hellenic Mediterranean University, 71004 Heraklion, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-7269-1994","authenticated-orcid":false,"given":"Stylianos","family":"Kostakis","sequence":"additional","affiliation":[{"name":"Componous P.C., 11 Kontopoulou Street, 53100 Florina, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-5470-5684","authenticated-orcid":false,"given":"Eleni","family":"Athanasaki","sequence":"additional","affiliation":[{"name":"Componous P.C., 11 Kontopoulou Street, 53100 Florina, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0797-5540","authenticated-orcid":false,"given":"Zhenyu","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Fiber Optical Sensor Systems, Fraunhofer Heinrich Hertz Institute, Am Stollen 19H, 38640 Goslar, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3147-8918","authenticated-orcid":false,"given":"Martin","family":"Angelmahr","sequence":"additional","affiliation":[{"name":"Department of Fiber Optical Sensor Systems, Fraunhofer Heinrich Hertz Institute, Am Stollen 19H, 38640 Goslar, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Manousos","family":"Konstadoulakis","sequence":"additional","affiliation":[{"name":"2nd Department of Surgery, Aretaieion University Hospital, National and Kapodistrian University of Athens (NKUA), 11528 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1976-8728","authenticated-orcid":false,"given":"Panagiotis","family":"Polygerinos","sequence":"additional","affiliation":[{"name":"Control Systems and Robotics Laboratory, Department of Mechanical Engineering, School of Engineering, Hellenic Mediterranean University, 71004 Heraklion, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e70019","DOI":"10.1002\/rcs.70019","article-title":"Tactile Feedback in Robot-Assisted Minimally Invasive Surgery: A Systematic 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