{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:20:09Z","timestamp":1760235609411,"version":"build-2065373602"},"reference-count":39,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2021,9,9]],"date-time":"2021-09-09T00:00:00Z","timestamp":1631145600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100017995","name":"Nora Eccles Treadwell Foundation","doi-asserted-by":"publisher","award":["NoID"],"award-info":[{"award-number":["NoID"]}],"id":[{"id":"10.13039\/100017995","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000050","name":"National Heart, Lung, and Blood Institute","doi-asserted-by":"publisher","award":["R01 HL135077","R56 HL128813"],"award-info":[{"award-number":["R01 HL135077","R56 HL128813"]}],"id":[{"id":"10.13039\/100000050","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Light-scattering spectroscopy (LSS) is an established optical approach for characterization of biological tissues. Here, we investigated the capabilities of LSS and convolutional neural networks (CNNs) to quantitatively characterize the composition and arrangement of cardiac tissues. We assembled tissue constructs from fixed myocardium and the aortic wall with a thickness similar to that of the atrial free wall. The aortic sections represented fibrotic tissue. Depth, volume fraction, and arrangement of these fibrotic insets were varied. We gathered spectra with wavelengths from 500\u20131100 nm from the constructs at multiple locations relative to a light source. We used single and combinations of two spectra for training of CNNs. With independently measured spectra, we assessed the accuracy of the CNNs for the classification of tissue constructs from single spectra and combined spectra. Combined spectra, including the spectra from fibers distal from the illumination fiber, typically yielded the highest accuracy. The maximal classification accuracy of the depth detection, volume fraction, and permutated arrangements was (mean \u00b1 standard deviation (stddev)) 88.97 \u00b1 2.49%, 76.33 \u00b1 1.51%, and 84.25 \u00b1 1.88%, respectively. Our studies demonstrate the reliability of quantitative characterization of tissue composition and arrangements using a combination of LSS and CNNs. The potential clinical applications of the developed approach include intraoperative quantification and mapping of atrial fibrosis, as well as the assessment of ablation lesions.<\/jats:p>","DOI":"10.3390\/s21186033","type":"journal-article","created":{"date-parts":[[2021,9,9]],"date-time":"2021-09-09T21:36:58Z","timestamp":1631223418000},"page":"6033","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Towards Intraoperative Quantification of Atrial Fibrosis Using Light-Scattering Spectroscopy and Convolutional Neural Networks"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4848-7554","authenticated-orcid":false,"given":"Nathan J.","family":"Knighton","sequence":"first","affiliation":[{"name":"Department of Biomedical Engineering, University of Utah, 36 South Wasatch Drive, Salt Lake City, UT 84112, USA"},{"name":"Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, 95 S 2000 E, Salt Lake City, UT 84112, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Brian K.","family":"Cottle","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, University of Utah, 36 South Wasatch Drive, Salt Lake City, UT 84112, USA"},{"name":"Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, 95 S 2000 E, Salt Lake City, UT 84112, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bailey E. B.","family":"Kelson","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, University of Utah, 36 South Wasatch Drive, Salt Lake City, UT 84112, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Robert W.","family":"Hitchcock","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, University of Utah, 36 South Wasatch Drive, Salt Lake City, UT 84112, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4987-705X","authenticated-orcid":false,"given":"Frank B.","family":"Sachse","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, University of Utah, 36 South Wasatch Drive, Salt Lake City, UT 84112, USA"},{"name":"Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, 95 S 2000 E, Salt Lake City, UT 84112, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"744","DOI":"10.1016\/S1542-3565(04)00345-3","article-title":"Optical Biopsy: A New Frontier in Endoscopic Detection and Diagnosis","volume":"2","author":"Wang","year":"2004","journal-title":"Clin. 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