{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T20:08:51Z","timestamp":1790194131308,"version":"4.1.0"},"reference-count":0,"publisher":"SPIE-Intl Soc Optical Eng","issue":"09","license":[{"start":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T00:00:00Z","timestamp":1789516800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"United States Air Force Office of Scientific Research","award":["FA9550-24-1-0112"],"award-info":[{"award-number":["FA9550-24-1-0112"]}],"id":[{"id":"https:\/\/ror.org\/011e9bt93","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["1P01CA254859"],"award-info":[{"award-number":["1P01CA254859"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Biomed. Opt."],"published-print":{"date-parts":[[2026,9,16]]},"abstract":"<jats:p>SignificanceWide-field fluorescence-guided imaging is inherently depth ambiguous. Multispectral imaging across NIR-I and NIR-II may encode depth because longer-wavelength fluorescence undergoes less diffuse broadening in tissue.AimThe study aims to determine whether wavelength-dependent radial spread profiles of subsurface indocyanine green (ICG) fluorescence can be used to estimate depth from a single excitation wavelength.ApproachICG phantoms (1 to 50 \u03bcM) were imaged through ex vivo chicken breast under 785\u00a0nm excitation using four emission bands spanning NIR-I and NIR-II. Radial spread profiles from high-dynamic-range images formed a multispectral dictionary, and depth was estimated with an inverse model evaluated leave-one-thickness-out across 2.2 to 6.0\u00a0mm under concentration-matched and concentration-randomized conditions, randomized exposure subsets, and spectral-band ablations, and compared with analytical and empirically calibrated scalar dual-emission fluorescence-ratio baselines of Leblond et\u00a0al. Two ICG-localized sentinel lymph nodes from a breast cancer specimen were analyzed ex vivo.ResultsLonger-wavelength channels produced more compact spread profiles, and full width at 20% peak intensity increased linearly with tissue thickness for all filters (R2=0.94 to 0.95). The NIR-II-only subset (940 and 1070\u00a0nm) yielded sub-millimeter root mean square error at every held-out thickness under both concentration conditions (0.32 to 0.66\u00a0mm), whereas the analytical and empirical scalar-ratio baselines yielded 1.58 to 5.24 and 1.13 to 2.74\u00a0mm. Clinical sentinel lymph nodes preserved the wavelength-dependent profile narrowing, with phantom-to-clinical normalized-width RMSE of 3.3% to 8.5%.ConclusionsWavelength-dependent fluorescence spread profiles across NIR-I and NIR-II can encode depth information for subsurface ICG targets, providing a wide-field, single-fluorophore, single-excitation approach compatible with emerging multispectral surgical imaging platforms.<\/jats:p>","DOI":"10.1117\/1.jbo.31.9.096004","type":"journal-article","created":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T14:08:51Z","timestamp":1789567731000},"page":"1-24","source":"Crossref","is-referenced-by-count":0,"title":["Depth estimation from wavelength-dependent fluorescence spread profiles across NIR-I and NIR-II"],"prefix":"10.1117","volume":"31","author":[{"given":"Dogancan E.","family":"Kuyel","sequence":"first","affiliation":[{"name":"Univ. of Illinois"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhongmin","family":"Zhu","sequence":"additional","affiliation":[{"name":"Univ. of Illinois"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brianna S.","family":"Hajek","sequence":"additional","affiliation":[{"name":"Univ. of Illinois"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sinisha","family":"Stojanovski","sequence":"additional","affiliation":[{"name":"Ss. Cyril and Methodius Univ."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anamarija","family":"Jankulovska","sequence":"additional","affiliation":[{"name":"Ss. Cyril and Methodius Univ."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Igorce","family":"Djikovski","sequence":"additional","affiliation":[{"name":"Ss. Cyril and Methodius Univ."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Risto","family":"Colanceski","sequence":"additional","affiliation":[{"name":"Ss. Cyril and Methodius Univ."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Imran","family":"Ferati","sequence":"additional","affiliation":[{"name":"Ss. Cyril and Methodius Univ."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Natasha Toleska","family":"Dimitrovska","sequence":"additional","affiliation":[{"name":"Ss. Cyril and Methodius Univ."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ilir","family":"Vela","sequence":"additional","affiliation":[{"name":"Ss. Cyril and Methodius Univ."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Despot","family":"Despotovski","sequence":"additional","affiliation":[{"name":"Ss. Cyril and Methodius Univ."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nexhati","family":"Jakupi","sequence":"additional","affiliation":[{"name":"Ss. Cyril and Methodius Univ."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Darko","family":"Angjushev","sequence":"additional","affiliation":[{"name":"Ss. Cyril and Methodius Univ."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0729-6700","authenticated-orcid":false,"given":"Magdalena","family":"Bogdanovska Todorovska","sequence":"additional","affiliation":[{"name":"Ss. Cyril and Methodius Univ."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Goran","family":"Kondov","sequence":"additional","affiliation":[{"name":"Ss. Cyril and Methodius Univ."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Borislav","family":"Kondov","sequence":"additional","affiliation":[{"name":"Ss. Cyril and Methodius Univ."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fumihiro","family":"Kawano","sequence":"additional","affiliation":[{"name":"Univ. of Illinois"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7328-1144","authenticated-orcid":false,"given":"Shuming","family":"Nie","sequence":"additional","affiliation":[{"name":"Univ. of Illinois"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Claudius","family":"Conrad","sequence":"additional","affiliation":[{"name":"Univ. of Illinois"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1280-7971","authenticated-orcid":false,"given":"Viktor","family":"Gruev","sequence":"additional","affiliation":[{"name":"Univ. of Illinois"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"189","container-title":["Journal of Biomedical Optics"],"original-title":[],"link":[{"URL":"https:\/\/www.spiedigitallibrary.org\/journals\/journal-of-biomedical-optics\/volume-31\/issue-09\/096004\/Depth-estimation-from-wavelength-dependent-fluorescence-spread-profiles-across-NIR\/10.1117\/1.JBO.31.9.096004.full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T19:54:26Z","timestamp":1790193266000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.spiedigitallibrary.org\/journals\/journal-of-biomedical-optics\/volume-31\/issue-09\/096004\/Depth-estimation-from-wavelength-dependent-fluorescence-spread-profiles-across-NIR\/10.1117\/1.JBO.31.9.096004.full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,16]]},"references-count":0,"journal-issue":{"issue":"09","published-online":{"date-parts":[[2026,9,1]]}},"URL":"https:\/\/doi.org\/10.1117\/1.jbo.31.9.096004","relation":{},"ISSN":["1083-3668","1560-2281"],"issn-type":[{"value":"1083-3668","type":"print"},{"value":"1560-2281","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,16]]}}}