{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T16:25:22Z","timestamp":1778257522444,"version":"3.51.4"},"reference-count":52,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2023,9,5]],"date-time":"2023-09-05T00:00:00Z","timestamp":1693872000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Project PO FESR Sicilia 2014\/2020\u2014Azione 1.1.5\u2014\u201cSostegno all\u2019avanzamento tecnologico delle imprese attraverso il finanziamento di linee pilota e azioni di validazione precoce dei prodotti e di dimostrazioni su larga scala\u201d\u20143DLab-Sicilia CUP G69J18001100007","award":["08CT4669990220"],"award-info":[{"award-number":["08CT4669990220"]}]},{"name":"Project PO FESR Sicilia 2014\/2020\u2014Azione 1.1.5\u2014\u201cSostegno all\u2019avanzamento tecnologico delle imprese attraverso il finanziamento di linee pilota e azioni di validazione precoce dei prodotti e di dimostrazioni su larga scala\u201d\u20143DLab-Sicilia CUP G69J18001100007","award":["FFR2023"],"award-info":[{"award-number":["FFR2023"]}]},{"name":"Unipa","award":["08CT4669990220"],"award-info":[{"award-number":["08CT4669990220"]}]},{"name":"Unipa","award":["FFR2023"],"award-info":[{"award-number":["FFR2023"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Oral capillaroscopy is a critical and non-invasive technique used to evaluate microcirculation. Its ability to observe small vessels in vivo has generated significant interest in the field. Capillaroscopy serves as an essential tool for diagnosing and prognosing various pathologies, with anatomic\u2013pathological lesions playing a crucial role in their progression. Despite its importance, the utilization of videocapillaroscopy in the oral cavity encounters limitations due to the acquisition setup, encompassing spatial and temporal resolutions of the video camera, objective magnification, and physical probe dimensions. Moreover, the operator\u2019s influence during the acquisition process, particularly how the probe is maneuvered, further affects its effectiveness. This study aims to address these challenges and improve data reliability by developing a computerized support system for microcirculation analysis. The designed system performs stabilization, enhancement and automatic segmentation of capillaries in oral mucosal video sequences. The stabilization phase was performed by means of a method based on the coupling of seed points in a classification process. The enhancement process implemented was based on the temporal analysis of the capillaroscopic frames. Finally, an automatic segmentation phase of the capillaries was implemented with the additional objective of quantitatively assessing the signal improvement achieved through the developed techniques. Specifically, transfer learning of the renowned U-net deep network was implemented for this purpose. The proposed method underwent testing on a database with ground truth obtained from expert manual segmentation. The obtained results demonstrate an achieved Jaccard index of 90.1% and an accuracy of 96.2%, highlighting the effectiveness of the developed techniques in oral capillaroscopy. In conclusion, these promising outcomes encourage the utilization of this method to assist in the diagnosis and monitoring of conditions that impact microcirculation, such as rheumatologic or cardiovascular disorders.<\/jats:p>","DOI":"10.3390\/s23187674","type":"journal-article","created":{"date-parts":[[2023,9,5]],"date-time":"2023-09-05T10:26:43Z","timestamp":1693909603000},"page":"7674","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Automated Stabilization, Enhancement and Capillaries Segmentation in Videocapillaroscopy"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8313-2556","authenticated-orcid":false,"given":"Vincenzo","family":"Taormina","sequence":"first","affiliation":[{"name":"Department of Mathematics and Informatics, University of Palermo, 90128 Palermo, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Giuseppe","family":"Raso","sequence":"additional","affiliation":[{"name":"Department of Physics and Chemistry, University of Palermo, 90128 Palermo, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3844-3136","authenticated-orcid":false,"given":"Vito","family":"Gentile","sequence":"additional","affiliation":[{"name":"Department of Physics and Chemistry, University of Palermo, 90128 Palermo, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Leonardo","family":"Abbene","sequence":"additional","affiliation":[{"name":"Department of Physics and Chemistry, University of Palermo, 90128 Palermo, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Antonino","family":"Buttacavoli","sequence":"additional","affiliation":[{"name":"Department of Physics and Chemistry, University of Palermo, 90128 Palermo, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gaetano","family":"Bonsignore","sequence":"additional","affiliation":[{"name":"Department of Physics and Chemistry, University of Palermo, 90128 Palermo, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4961-2054","authenticated-orcid":false,"given":"Cesare","family":"Valenti","sequence":"additional","affiliation":[{"name":"Department of Mathematics and Informatics, University of Palermo, 90128 Palermo, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pietro","family":"Messina","sequence":"additional","affiliation":[{"name":"Department of Surgical Oncological and Stomatological Disciplines, University of Palermo, 90127 Palermo, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7305-530X","authenticated-orcid":false,"given":"Giuseppe Alessandro","family":"Scardina","sequence":"additional","affiliation":[{"name":"Department of Surgical Oncological and Stomatological Disciplines, University of Palermo, 90127 Palermo, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6522-1259","authenticated-orcid":false,"given":"Donato","family":"Cascio","sequence":"additional","affiliation":[{"name":"Department of Physics and Chemistry, University of Palermo, 90128 Palermo, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"371","DOI":"10.1016\/j.aanat.2009.04.004","article-title":"Anatomical evaluation of oral microcirculation: Capillary characteristics associated with sex or age group","volume":"191","author":"Scardina","year":"2009","journal-title":"Ann. 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