{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,13]],"date-time":"2026-08-13T08:30:56Z","timestamp":1786609856102,"version":"build-2736575974"},"reference-count":24,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,7]],"date-time":"2026-08-07T00:00:00Z","timestamp":1786060800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004837","name":"Spanish Ministry of Science and Innovation","doi-asserted-by":"publisher","award":["PID2021-127691OB-I00"],"award-info":[{"award-number":["PID2021-127691OB-I00"]}],"id":[{"id":"10.13039\/501100004837","id-type":"DOI","asserted-by":"publisher"}]},{"award":["PID2021-127691OB-I00"],"award-info":[{"award-number":["PID2021-127691OB-I00"]}],"id":[{"id":"https:\/\/ror.org\/023ktd084","id-type":"ROR","asserted-by":"publisher"}]},{"name":"FEDER funds"},{"name":"Government of Cantabria"},{"DOI":"10.13039\/501100015650","name":"Carolina Foundation","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100015650","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Real-time tissue identification during laser-guided surgery is a critical unmet need for collateral damage avoidance and margin delineation. Laser-Induced Breakdown Spectroscopy (LIBS) is compatible with pulsed laser surgical systems and offers rapid, label-free elemental analysis. This study presents a machine learning pipeline classifying five ex vivo bovine tissue classes, plus one synthetic null-signal control class, from LIBS spectra, designed to control specimen-level data leakage and class imbalance bias. Key contributions are (i) a \u2018peak max over baseline\u2019 aggregation strategy suppressing shot noise while preserving emission peaks; (ii) a repeated, group-based cross-validation protocol (GroupShuffleSplit, N = 10) enforcing specimen-level separation; and (iii) a comparison of 30 configurations (10 classifiers \u00d7 3 pipelines). Extra Trees with normalization reached the highest weighted F1-score (0.934 \u00b1 0.118); excluding the synthetic control, five-class scores fall to 0.875\u20130.915 and the ranking changes, so these are the reference figures for biological tissue discrimination. Support Vector Machines were less accurate but more consistent (0.917 \u00b1 0.069). Acquisition takes approximately 3 s per point; inference is sub-millisecond. With five source animals, the best configuration chosen on the same outer splits, and inner tuning that was not group-aware, these estimates are an exploratory step toward real-time guided surgery.<\/jats:p>","DOI":"10.3390\/s26165020","type":"journal-article","created":{"date-parts":[[2026,8,7]],"date-time":"2026-08-07T13:20:16Z","timestamp":1786108816000},"page":"5020","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Specimen-Separated Machine Learning Benchmark Toward Real-Time Tissue-Type Identification in Guided Surgery Using Ex Vivo Bovine Laser-Induced Breakdown Spectroscopy"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-0339-8402","authenticated-orcid":false,"given":"Ren\u00e9 Fernando","family":"Sosa-Santos","sequence":"first","affiliation":[{"name":"Biomedical Engineering Group, TEISA Department, Universidad de Cantabria, 39005 Santander, Spain"},{"name":"Optical and Energy Research Center, Universidad Privada Boliviana, Cochabamba, Bolivia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5403-4404","authenticated-orcid":false,"given":"Jos\u00e9 Luis","family":"Arce-Diego","sequence":"additional","affiliation":[{"name":"Biomedical Engineering Group, TEISA Department, Universidad de Cantabria, 39005 Santander, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0739-3946","authenticated-orcid":false,"given":"F\u00e9lix","family":"Fanjul-V\u00e9lez","sequence":"additional","affiliation":[{"name":"Biomedical Engineering Group, TEISA Department, Universidad de Cantabria, 39005 Santander, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"717","DOI":"10.1245\/s10434-014-3480-5","article-title":"The association of surgical margins and local recurrence in women with early-stage invasive breast cancer treated with breast-conserving therapy: A meta-analysis","volume":"21","author":"Houssami","year":"2014","journal-title":"Ann. 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