{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,11]],"date-time":"2026-05-11T11:34:42Z","timestamp":1778499282202,"version":"3.51.4"},"reference-count":48,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2022,9,21]],"date-time":"2022-09-21T00:00:00Z","timestamp":1663718400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Korea Medical Device Development Fund","award":["KMDF_PR_20200901_0119"],"award-info":[{"award-number":["KMDF_PR_20200901_0119"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Radar is a promising non-contact sensor for overnight polysomnography (PSG), the gold standard for diagnosing obstructive sleep apnea (OSA). This preliminary study aimed to demonstrate the feasibility of the automated detection of apnea-hypopnea events for OSA diagnosis based on 60 GHz frequency-modulated continuous-wave radar using convolutional recurrent neural networks. The dataset comprised 44 participants from an ongoing OSA cohort, recruited from July 2021 to April 2022, who underwent overnight PSG with a radar sensor. All PSG recordings, including sleep and wakefulness, were included in the dataset. Model development and evaluation were based on a five-fold cross-validation. The area under the receiver operating characteristic curve for the classification of 1-min segments ranged from 0.796 to 0.859. Depending on OSA severity, the sensitivities for apnea-hypopnea events were 49.0\u201367.6%, and the number of false-positive detections per participant was 23.4\u201352.8. The estimated apnea-hypopnea index showed strong correlations (Pearson correlation coefficient = 0.805\u20130.949) and good to excellent agreement (intraclass correlation coefficient = 0.776\u20130.929) with the ground truth. There was substantial agreement between the estimated and ground truth OSA severity (kappa statistics = 0.648\u20130.736). The results demonstrate the potential of radar as a standalone screening tool for OSA.<\/jats:p>","DOI":"10.3390\/s22197177","type":"journal-article","created":{"date-parts":[[2022,9,22]],"date-time":"2022-09-22T23:07:55Z","timestamp":1663888075000},"page":"7177","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":34,"title":["Automated Detection of Sleep Apnea-Hypopnea Events Based on 60 GHz Frequency-Modulated Continuous-Wave Radar Using Convolutional Recurrent Neural Networks: A Preliminary Report of a Prospective Cohort Study"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5937-7238","authenticated-orcid":false,"given":"Jae Won","family":"Choi","sequence":"first","affiliation":[{"name":"Department of Radiology, Armed Forces Yangju Hospital, Yangju 11429, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3871-7002","authenticated-orcid":false,"given":"Dong Hyun","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Radiology, Seoul Metropolitan Government\u2014Seoul National University Boramae Medical Center, Seoul National University College of Medicine, Seoul 07061, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6858-6093","authenticated-orcid":false,"given":"Dae Lim","family":"Koo","sequence":"additional","affiliation":[{"name":"Department of Neurology, Seoul Metropolitan Government\u2014Seoul National University Boramae Medical Center, Seoul National University College of Medicine, Seoul 07061, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8765-9988","authenticated-orcid":false,"given":"Yangmi","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Neurology, Seoul Metropolitan Government\u2014Seoul National University Boramae Medical Center, Seoul National University College of Medicine, Seoul 07061, Korea"}]},{"given":"Hyunwoo","family":"Nam","sequence":"additional","affiliation":[{"name":"Department of Neurology, Seoul Metropolitan Government\u2014Seoul National University Boramae Medical Center, Seoul National University College of Medicine, Seoul 07061, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5485-2776","authenticated-orcid":false,"given":"Ji Hyun","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Radiology, Seoul Metropolitan Government\u2014Seoul National University Boramae Medical Center, Seoul National University College of Medicine, Seoul 07061, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0549-5722","authenticated-orcid":false,"given":"Hyo Jin","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Radiology, Seoul Metropolitan Government\u2014Seoul National University Boramae Medical Center, Seoul National University College of Medicine, Seoul 07061, Korea"}]},{"given":"Seung-No","family":"Hong","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology-Head and Neck Surgery, Seoul Metropolitan Government\u2014Seoul National University Boramae Medical Center, Seoul National University College of Medicine, Seoul 07061, Korea"}]},{"given":"Gwangsoo","family":"Jang","sequence":"additional","affiliation":[{"name":"AU Inc., Daejeon 34141, Korea"}]},{"given":"Sungmook","family":"Lim","sequence":"additional","affiliation":[{"name":"AU Inc., Daejeon 34141, Korea"}]},{"given":"Baekhyun","family":"Kim","sequence":"additional","affiliation":[{"name":"AU Inc., Daejeon 34141, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1545","DOI":"10.4065\/78.12.1545","article-title":"Obstructive sleep apnea-hypopnea syndrome","volume":"78","author":"Olson","year":"2003","journal-title":"Mayo Clin. 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