Automatic Pharyngeal Phase Recognition in Untrimmed Videofluoroscopic Swallowing Study Using Transfer Learning with Deep Convolutional Neural Networks.

BACKGROUND: Video fluoroscopic swallowing study (VFSS) is considered as the gold standard diagnostic tool for evaluating dysphagia. However, it is time consuming and labor intensive for the clinician to manually search the recorded long video image frame by frame to identify the instantaneous swallowing abnormality in VFSS images. Therefore, this study aims to present a deep leaning-based approach using transfer learning with a convolutional neural network (CNN) that automatically annotates pharyngeal phase frames in untrimmed VFSS videos such that frames need not be searched manually. METHODS: To determine whether the image frame in the VFSS video is in the pharyngeal phase, a single-frame baseline architecture based the deep CNN framework is used and a transfer learning technique with fine-tuning is applied. RESULTS: Compared with all experimental CNN models, that fine-tuned with two blocks of the VGG-16 (VGG16-FT5) model achieved the highest performance in terms of recognizing the frame of pharyngeal phase, that is, the accuracy of 93.20 (±1.25)%, sensitivity of 84.57 (±5.19)%, specificity of 94.36 (±1.21)%, AUC of 0.8947 (±0.0269) and Kappa of 0.7093 (±0.0488). CONCLUSIONS: Using appropriate and fine-tuning techniques and explainable deep learning techniques such as grad CAM, this study shows that the proposed single-frame-baseline-architecture-based deep CNN framework can yield high performances in the full automation of VFSS video analysis.

The incidence, prevalence, and survival rate of thromboangiitis obliterans in Korea: a retrospective population-based study.

BACKGROUND: Few studies used nationwide data to assess the age-standardized prevalence rate, incidence rate, 10-year survival rate, and death risk of thromboangiitis obliterans (TAO; Buerger's disease). METHODS: Data for 24,392 patients who had newly diagnoses related to TAO (I73.1) from 2006 through 2017 were extracted from the National Health Insurance Service in Korea. The age-standardized prevalence rate, incidence rate, 10-year survival rate, and death risk of TAO were analyzed. RESULTS: The mean (standard deviation) age of TAO patients overall was 62.0 (15.7) years; 61.3 (15.4) in males and 63.2 (16.1) in females (P<0.001). The proportion of patients older than 50 years old was about 80% overall. The proportion patients who died of TAO was 28.1%. Overall, the age-standardized prevalence rate of TAO decreased from 11.1 persons per 100,000 persons in 2006 to 8.43 persons in 2017, and overall, the incidence rate of TAO decreased from 6.07 persons in 2006 to 3.38 persons in 2017. The age-standardized prevalence rate and incidence rate in males were higher than that in females. The 10-year survival rate of TAO was about 65% (60.7% in males and 72.5% in females). The adjusted hazard ratio increased significantly with older age, male sex, hypertension, diabetes mellitus, myocardial infarction, heart failure, ischemic stroke, hemorrhagic stroke, chronic kidney disease, and malignant neoplasm. CONCLUSIONS: The 10-year survival rate of TAO was about 65%. Even though the age-standardized prevalence rate and incidence rate of TAO is decreased during the study period, the adjusted hazard ratio showed significantly increases with age and with male sex after adjustment for comorbidities.

Prevalence of Amyloidosis in Korea.

BACKGROUND: The aim of this study was to assess in amyloidosis prevalence in Korea between 2006 and 2015. METHODS: Primary diagnoses related to amyloidosis, regardless of subtype, were collected from the Korean National Health Insurance Service from 2006 through 2015. RESULTS: Overall, the age-standardized prevalence of amyloidosis was 0.93 (95% confidence interval (CI) 0.81, 1.04) persons per 100,000 persons in 2006 and 1.91 (95% CI 1.78, 2.05) persons per 100,000 persons in 2015. This included an increase from 0.43 (95% CI 0.35, 0.51) to 1.04 (95% CI 0.94, 1.14) persons per 100,000 persons in men and from 0.49 (95% CI 0.40, 0.57) to 0.87 (95% CI 0.77, 0.96) persons per 100,000 persons in women. In particular, the age-standardized prevalence of amyloidosis showed a greater increase in patients aged 65 years or older and in patients aged 45-64 years than in patients aged 20-44 years, for both men and women. CONCLUSIONS: The overall age-standardized prevalence of amyloidosis was approximately 2 persons per 100,000 persons in 2015. The overall age-standardized prevalence of amyloidosis increased between 2006 and 2015, especially in individuals aged 45-64 and older than 65 years.

Association between restriction of activity related to chronic diseases and suicidal ideation in older adults in Korea.

AIM: The aim of the present study was to show an association between restricted activity related to chronic diseases and suicidal ideation (SI) in elderly Korean adults after adjusting for age, sex, mental health status, socioeconomic position and health behavior factors. METHODS: The study sample included 3545 Korean men (n=1473) and women (n=2073), aged over 65 years from the 2007-2009 Korea National Health and Nutrition Examination Survey carried out by the Ministry of Health and Welfare of Korea. Participants were classified into two groups based on whether they had previously experienced suicidal thoughts. Restricted activity was related to chronic conditions, such as cardiovascular diseases, cerebrovascular accident and so on. We analyzed the data using Student's t-test or χ(2) -test. Multiple logistic regression analysis was used to determine the association between restricted activity as the independent variable and SI as the dependent variable after adjustment for confounders. RESULTS: The proportion of participants with SI population was 29.1%. People with SI reported a significantly higher proportion of restrictive activity (62.3%) than those who did not have SI (34.5%). The adjusted risk excess (OR) of SI was statistically significant with regard to restricted activity (2.11, 95% CI 1.65-2.70; 2.85, 95% CI 1.95-4.15) in males; 1.69 (95% CI 1.22-2.34) in females after adjustment for potential confounders. In particular, women who lived alone showed high adjusted OR (1.50, 95% CI 1.01-2.24). CONCLUSIONS: Statistical analyses from this community-based, random sample drawn from a selected sample of the elderly Korean population showed that restricted activity appears to be significantly associated with SI.