Inn-Chul Nam

Prof. Dr. Inn-Chul Nam

orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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20 May 2022 in Cancers
Verified
Journal Article
Open access
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JPJun-Ook Park
Jun-Ook Park
INInn-Chul Nam
Inn-Chul Nam
CKChoung-Soo Kim
Choung-Soo Kim
SPSung Joon Park
Sung Joon Park
DLDong-Hyun Lee
Dong-Hyun Lee
YJYoung Hoon Joo
Young Hoon Joo
Background: Descriptive epidemiologists have repeatedly reported that males are more susceptible to head and neck cancers. However, most published data are those of cross-sectional studies, and no population-based cohort study has yet been published. The aim of this study was to compare the prevalence of head and neck cancers in healthy males with females. Methods: A retrospective cohort study using the Korean National Health Insurance Service database on 9,598,085 individuals who underwent regular health checkups from 1 January to 31 December 2009. We sought head and neck cancers developed during the 10-year follow-up. Results: A total of 10,732 (incidence rate (IR) per 1000 person-years 0.25) individuals were newly diagnosed with head and neck cancer among the 9,598,085 individuals during the 10-year follow-up. The IR was 0.19 in males (8500 affected) and 0.06 in females (2232 affected). Notably, the male–female ratio increased with age below 70 years but decreased thereafter. The male–female difference was most apparent for laryngeal cancer; the male IR was 11-fold higher in the 40 s and 20-fold higher in the 60 s, followed by hypopharyngeal cancer (6.8- and 24.2-fold). Males smoked more and drank more alcohol than females (p < 0.0001 *, p < 0.0001 *). When never-smokers/-drinkers (only) were compared, males remained at a 2.9-fold higher risk of head and neck cancer than females. The hazard ratios for head and neck cancers in males tended to increase in the lower part of the upper aerodigestive tract: larynx (13.9) > hypopharynx (10.9) > oropharynx (4.4) > nasopharynx (2.9) > sinonasal region (1.8) > oral (1.6). Only the salivary gland cancer incidence did not differ between the sexes; the gland is not in the upper aerodigestive tract. Conclusion: Males are much more susceptible to head and neck cancers than females regardless of whether they drink alcohol or smoke tobacco. Sex differences in the incidence of head and neck cancer are most evident in the 60 s in the lower part of the upper aerodigestive tract, such as the larynx and hypopharynx.

18 May 2021 in JMIR Medical Informatics
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Journal Article
Open access
HLHaeyun Lee
Haeyun Lee
YCYoung Jun Chai
Young Jun Chai
HJHyunjin Joo
Hyunjin Joo
KLKyungsu Lee
Kyungsu Lee
JHJae Youn Hwang
Jae Youn Hwang
HKHyounJoong Kong
HyounJoong Kong
Background: Federated learning is a decentralized approach to machine learning; it is a training strategy that overcomes medical data privacy regulations and generalizes deep learning algorithms. Federated learning mitigates many systemic privacy risks by sharing only the model and parameters for training, without the need to export existing medical data sets. In this study, we performed ultrasound image analysis using federated learning to predict whether thyroid nodules were benign or malignant. Objective: The goal of this study was to evaluate whether the performance of federated learning was comparable with that of conventional deep learning. Methods: A total of 8457 (5375 malignant, 3082 benign) ultrasound images were collected from 6 institutions and used for federated learning and conventional deep learning. Five deep learning networks (VGG19, ResNet50, ResNext50, SE-ResNet50, and SE-ResNext50) were used. Using stratified random sampling, we selected 20% (1075 malignant, 616 benign) of the total images for internal validation. For external validation, we used 100 ultrasound images (50 malignant, 50 benign) from another institution. Results: For internal validation, the area under the receiver operating characteristic (AUROC) curve for federated learning was between 78.88% and 87.56%, and the AUROC for conventional deep learning was between 82.61% and 91.57%. For external validation, the AUROC for federated learning was between 75.20% and 86.72%, and the AUROC curve for conventional deep learning was between 73.04% and 91.04%. Conclusions: We demonstrated that the performance of federated learning using decentralized data was comparable to that of conventional deep learning using pooled data. Federated learning might be potentially useful for analyzing medical images while protecting patients’ personal information.

26 May 2024 in Healthcare
Verified
Journal Article
Open access
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EKEun-Jeong Kim
Eun-Jeong Kim
YKYoo-Ri Koo
Yoo-Ri Koo
INInn-Chul Nam
Inn-Chul Nam
Effective communication between patients and healthcare providers is essential for a positive patient experience (PE), and improving patient-centered care (PCC) involves many factors. This study aimed to (1) identify the factors that affect PE improvement, (2) reflect patients and healthcare providers’ perspectives on the factors’ importance, and (3) present a structural model for improving PCC. A systematic review of empirical studies that specified PE factors was conducted. Studies that did not reflect users’ perspectives and non-empirical studies were excluded. The literature was searched using Google Scholar, PubMed, Web of Science, and the Taylor and Francis online journal. The MMAT 2018 checklist was used to assess bias in the included studies, and frequency, content, and thematic analyses were employed to synthesize the results, yielding 25 articles. The 80 PE factors identified from the analyses were categorized into six categories: Practice, Physical Needs, Psychological Needs, Social Needs, Practical Needs, and Information Needs. From a user perspective, patients emphasized professional, continuous, and comprehensive service delivery, whereas healthcare providers stressed efficient system improvements and positive provider–patient relationships. We propose a structured model for PCC improvement using a service blueprint and system map. The PCC model provides an overview of the interactions and the roles of all stakeholders regarding quality of care to improve healthcare.

1 February 2022 in Clinical and Experimental Otorhinolaryngology
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Journal Article
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PLPhoniatrics And Logopedics Guideline Task Force Korean Society Of Laryngology
Phoniatrics And Logopedics Guideline Task Force Korean Society Of Laryngology
CRChang Hwan Ryu
Chang Hwan Ryu
SLSeung Jin Lee
Seung Jin Lee
JCJae-Gu Cho
Jae-Gu Cho
ICIk Joon Choi
Ik Joon Choi
JLJae-Yol Lim
Jae-Yol Lim
Voice change is a common complaint after thyroid surgery and has a significant impact on quality of life. The Korean Society of Laryngology, Phoniatrics and Logopedics assembled a task force to establish guideline recommendations on education, care, and management related to thyroid surgery. The guideline recommendations encompass preoperative voice education, management of anticipated voice change during surgery, and comprehensive voice care after thyroid surgery, and include in-depth information and up-to-date knowledge based on validated literature. The committee constructed 14 key questions (KQs) in three categories—preoperative (KQ 1–2), intraoperative (KQ 3–8), and postoperative (KQ 9–14) management—and developed 18 evidence-based recommendations. The Delphi survey reached an agreement on each recommendation. A detailed evidence profile is presented for each recommendation. The level of evidence for each recommendation was classified as high-quality, moderate-quality, or low-quality. The strength of each recommendation was designated as strong or weak considering the level of evidence supporting the recommendation. The guidelines are primarily targeted toward physicians who treat thyroid surgery patients and speech-language pathologists participating in patient care. These guidelines will also help primary care physicians, nurses, healthcare policymakers, and patients improve their understanding of voice changes and voice care after thyroid surgery.

17 June 2022 in Cancers
Verified
Journal Article
Open access
PDF file
DLDong-Hyun Lee
Dong-Hyun Lee
GKGeun-Jeon Kim
Geun-Jeon Kim
HKhyunbum Kim
hyunbum Kim
HSHyun-Il Shin
Hyun-Il Shin
CKChoung-Soo Kim
Choung-Soo Kim
JPJun-Ook Park
Jun-Ook Park
Introduction. Mucosal margins exhibit a mean shrinkage of 30–40% after resection of oral and oropharyngeal cancers, and an adequate in situ surgical margin frequently results in a pathological close margin. However, the impact on prognosis remains unclear. We investigated the impact of a pathological close margin on disease-free survival (DFS) and overall survival (OS). Methods. We retrospectively reviewed the clinicopathological data of 418 patients diagnosed with squamous cell carcinomas of the oral cavity or oropharynx who underwent initial surgery (with curative intent) at our institute between 2010 and 2016. Results. Of the total population, the pathological marginal status of 290 (69.4%) patients was reported as clear (>5 mm), 61 (14.6%) as close (>1 mm, ≤5 mm), and 67 (16.0%) as positive (≤1 mm). The 5-year DFSs were 79.3%, 65.1%, and 52% in patients in the negative margin (group 1), close margin (group 2), and positive margin (group 3) groups, respectively. The difference between groups 1 and 2 was not significant (p = 0.213) but the difference between groups 2 and 3 was (p = 0.034). The 5-year OSs were 79.4%, 84%, and 52.3% in groups 1, 2, and 3, respectively. The difference between groups 1 and 2 was not significant (p = 0.824) but the difference between groups 2 and 3 was (p = 0.001). In multivariate analysis, older age, advanced T stage, and a positive margin were independently prognostic of the 5-year DFS and OS. Conclusion. In conclusion, the OS of patients with close margins was no different than that of others when appropriate postoperative adjuvant and/or salvage treatment were/was prescribed. However, we could not determine the impact of close margins on locoregional recurrence given various biases in our study setting. A future prospective study is needed.

1 November 2020 in Clinical and Experimental Otorhinolaryngology
Verified
Journal Article
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KFKorean Bronchoesophagological Society Guideline Task Force
Korean Bronchoesophagological Society Guideline Task Force
INInn-Chul Nam
Inn-Chul Nam
YSYoo Seob Shin
Yoo Seob Shin
WJWoo-Jin Jeong
Woo-Jin Jeong
MPMin Woo Park
Min Woo Park
DSDong-Il Sun
Dong-Il Sun
The Korean Bronchoesophagological Society appointed a task force to develop a clinical practice guideline for tracheostomy. The task force conducted a systematic search of the Embase, Medline, Cochrane Library, and KoreaMed databases to identify relevant articles, using search terms selected according to key questions. Evidence-based recommendations for practice were ranked according to the American College of Physicians grading system. An external expert review and a Delphi questionnaire were conducted to reach a consensus regarding the recommendations. Accordingly, the committee developed 18 evidence-based recommendations, which are grouped into seven categories. These recommendations are intended to assist clinicians in performing tracheostomy and in the management of tracheostomized patients.