{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T05:55:41Z","timestamp":1771048541446,"version":"3.50.1"},"reference-count":39,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,5,6]],"date-time":"2021-05-06T00:00:00Z","timestamp":1620259200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Research Foundation of Korea (NRF), the Ministry of Education","award":["2018R1A6A1A03025523"],"award-info":[{"award-number":["2018R1A6A1A03025523"]}]},{"name":"the Ministry of Science and ICT of Korea","award":["2019R1A2C1006814"],"award-info":[{"award-number":["2019R1A2C1006814"]}]},{"name":"the Korea Medical Device Development Fund grant funded by the Korea government","award":["KMDF_PR_20200901_0026"],"award-info":[{"award-number":["KMDF_PR_20200901_0026"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The quantification of blood flow velocity in the human conjunctiva is clinically essential for assessing microvascular hemodynamics. Since the conjunctival microvessel is imaged in several seconds, eye motion during image acquisition causes motion artifacts limiting the accuracy of image segmentation performance and measurement of the blood flow velocity. In this paper, we introduce a novel customized optical imaging system for human conjunctiva with deep learning-based segmentation and motion correction. The image segmentation process is performed by the Attention-UNet structure to achieve high-performance segmentation results in conjunctiva images with motion blur. Motion correction processes with two steps\u2014registration and template matching\u2014are used to correct for large displacements and fine movements. The image displacement values decrease to 4\u20137 \u03bcm during registration (first step) and less than 1 \u03bcm during template matching (second step). With the corrected images, the blood flow velocity is calculated for selected vessels considering temporal signal variances and vessel lengths. These methods for resolving motion artifacts contribute insights into studies quantifying the hemodynamics of the conjunctiva, as well as other tissues.<\/jats:p>","DOI":"10.3390\/s21093224","type":"journal-article","created":{"date-parts":[[2021,5,6]],"date-time":"2021-05-06T11:10:27Z","timestamp":1620299427000},"page":"3224","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Quantification of Blood Flow Velocity in the Human Conjunctival Microvessels Using Deep Learning-Based Stabilization Algorithm"],"prefix":"10.3390","volume":"21","author":[{"given":"Hang-Chan","family":"Jo","sequence":"first","affiliation":[{"name":"Department of Electrical and Computer Engineering, Inha University, Incheon 22212, Korea"},{"name":"Center for Sensor Systems, Inha University, Incheon 22212, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hyeonwoo","family":"Jeong","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, Inha University, Incheon 22212, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Junhyuk","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, Inha University, Incheon 22212, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kyung-Sun","family":"Na","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology &amp; Visual Science, Yeouido St. Mary\u2019s Hospital, College of Medicine, The Catholic University of Korea, Seoul 07345, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dae-Yu","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, Inha University, Incheon 22212, Korea"},{"name":"Center for Sensor Systems, Inha University, Incheon 22212, Korea"},{"name":"Inha Research Institute for Aerospace Medicine, Inha University, Incheon 22212, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1038\/srep45916","article-title":"Assessment of conjunctival microvascular hemodynamics in stages of diabetic microvasculopathy","volume":"7","author":"Khansari","year":"2017","journal-title":"Sci. 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