1.Age Estimation Using Convolutional Neural Networks with Lumbar and Thoracic Spine Images from Postmortem Computed Tomography: A Pilot Study
Ju-Heon LEE ; Jin-Woo KIM ; Kyung-Ryoul KIM ; In-Soo SEO ; Nak-Won LEE ; Chang-Un CHOI ; Hye-Jeong KIM ; Byung-Yoon ROH
Korean Journal of Legal Medicine 2026;50(1):1-8
In forensic medicine, age estimation commonly involves assessing age-related changes in teeth and skeletal structures. Vertebral morphological alterations, such as osteophyte formation, serve as age indicators. Recent studies using deep-learning techniques, such as neural networks, for age estimation from radiographic images have been conducted, reporting significantly higher accuracy than previous studies. This study aimed to estimate age using neural network-based deep-learning techniques applied to computed tomography (CT) cross-sectional images of the spine and evaluate its feasibility. Postmortem CT scans of 214 cadavers with varying decomposition levels were used. Coronal and sagittal cross-sectional images penetrating the center of each vertebral body were extracted for the 11th and 12th thoracic vertebrae and the first to fifth lumbar vertebrae. Using these images, along with the chronological ages of deceased individuals, an age estimation model was developed through regression analysis in PyTorch, employing a convolutional neural networks architecture with five-fold cross-validation. The model achieved a mean absolute error of 5.385 years, root mean squared error of 7.029 years, and coefficient of determination of 0.793. Although the sample size was relatively small, the results suggested the potential applicability of vertebral imagingbased age estimation in the Korean population. Further research using a larger dataset may improve the accuracy and reliability of the model.
2.Muscle Loss Driven by Extracellular Signal-Regulated Kinase Suppression via β-Adrenergic Activation in High-Normal Catecholamine Status
Jieun LEE ; Ju Yeon KWAK ; Ho Yeop LEE ; Ji Sun MOON ; Hyo Ju JANG ; Ha Thi NGA ; Thi Linh NGUYEN ; Alfin Mohammad ABDILLAH ; Junglyun KIM ; Sihwan KIM ; Yong Ryoul YANG ; Jeong Eun LEE ; Hyon-Seung YI
Endocrinology and Metabolism 2026;41(2):319-332
Background:
Catecholamines play a crucial role in muscle biogenesis, but their persistent elevation is linked to muscle wasting, which is poorly understood. This study aimed to investigate the association between catecholamine levels and age-related muscle loss.
Methods:
This retrospective study evaluated the plasma levels of two catecholamines, metanephrine and normetanephrine, and the clinical characteristics of 830 patients with adrenal incidentaloma on computed tomography (CT). Cross-sectional CT data at the L3 lumbar vertebrae were used to measure muscle areas. In vitro studies on C2C12 myotubes were conducted to examine β-adrenergic receptor signaling pathways and their role in myogenesis.
Results:
Men had significantly higher mean metanephrine levels of 0.17 nmol/L and normetanephrine levels of 0.63 nmol/L than women (P<0.05). Total abdominal muscle area was negatively correlated with catecholamine levels in both men and women, with the strongest negative correlation between normetanephrine levels and total abdominal muscle area in men (r=–0.31, P<0.001). Similarly, the strongest negative correlation between visceral fat area and metanephrine was observed in men (r=–0.25, P=0.004). Clenbuterol, a β-adrenergic receptor agonist, inhibited myogenesis, including myotube formation by extracellular signal-regulated kinase (ERK) suppression in C2C12 myoblasts. Conversely, β-blockers increased myogenesis via increasing ERK phosphorylation in C2C12 cells. These findings suggest that β-adrenergic modulation influences skeletal muscle differentiation, with ERK phosphorylation.
Conclusion
Catecholamine levels are associated with age, sex, muscle mass, and fat mass. Monitoring catecholamine levels, particularly in older men and in individuals with reduced muscle mass, may help manage age-related muscle loss and lead to individualized treatment strategies.
3.Dental Age Estimation in Children Using Convolution Neural Network Algorithm: A Pilot Study
Byung-Yoon ROH ; Hyun-Jeong PARK ; Kyung-Ryoul KIM ; In-Soo SEO ; Yeon-Ho OH ; Ju-Heon LEE ; Chang-Un CHOI ; Yo-Seob SEO ; Ji-Won RYU ; Jong-Mo AHN
Journal of Oral Medicine and Pain 2024;49(4):118-123
Purpose:
Recently, deep learning techniques have been introduced for age estimation, with automated methods based on radiographic analysis demonstrating high accuracy. In this study, we applied convolutional neural network (CNN) techniques to the lower dentition area on orthopantomograms (OPGs) of children to develop an automated age estimation model and evaluate its accuracy for use in forensic dentistry.
Methods:
In this study, OPGs of 2,856 subjects aged 3-14 years were analyzed. The You Only Look Once (YOLO) V8 object detection technique was applied to extract the mandibular dentition area on OPGs, designating it as the region of interest (ROI). First, 200 radiographs were randomly selected, and were used to train a model for extracting the ROI. The trained model was then applied to the entire dataset. For the CNN image classification task, 80% of OPGs were allocated to the training set, while the remaining 20% were used as the test set. A transfer learning approach was employed using the ResNet50 and VGG19 backbone models, with an ensemble technique combining these models to improve performance. The mean absolute error (MAE) on the test set was used as the validation metric, and the model with the lowest MAE was selected.
Results:
In this study, the age estimation model developed using mandibular dentition region from OPGs achieved MAE and root mean squared error (RMSE) values of 0.501 and 0.742, respectively, on the test set, and MAE and RMSE values of 0.273 and 0.354, respectively, on the training set.
Conclusions
The automated age estimation model developed in this study demonstrated accuracy comparable to that of previous research and shows potential for applications in forensic investigations. Increasing the sample size and incorporating diverse deep learning techniques are expected to further enhance the accuracy of future age estimation models.
4.The Significance of Detecting Diatoms in Spleen Tissue for the Postmortem Diagnosis of Drowning
Young San KO ; Suk Hoon HAM ; Jin-Haeng HEO ; Sang-Beom IM ; Young-Il PARK ; Jeong-hwa KWON ; Kyung Ryoul KIM ; Ho Suk SONG ; Seon Jung JANG
Korean Journal of Legal Medicine 2024;48(1):1-6
The aim of this study was to elucidate the diatomological investigation and the forensic role of spleen tissue in cases of drowning or non-drowning. Specimens of spleen tissue and other organ tissue from 136 drowning cases, as well as 21 cases where death resulted from causes other than drowning (acting as controls), were examined for the presence of diatoms. The diatom test was performed on all cases using the acid digestion method, involving fumed nitric acid on a hot sand bath. The presence of diatoms in spleen tissue was observed in drowning cases but not in non-drowning cases. Diatoms in spleen tissue showed a positive association with drowning (P=0.011). Among the 136 drowning cases, diatoms were most frequently found in lung tissue (n=134, 99%), followed by spleen (n=33, 24%), kidney (n=28, 21%), liver (n=27, 20%), and heart (n=22, 16%) tissues. Moreover, in 95 cases where putrefaction did not progress, diatoms were detected in spleen tissues in 14 cases, indicating that the highest detection rate among other enclosed organ tissues, excluding lung tissues. Furthermore, a significant correlation was observed between the presence of diatoms in spleen tissue and those in enclosed organs, including the liver, kidney, and heart, but not in lung tissues. Our results revealed a significant correlation between the presence of diatoms in spleen tissue and drowning. Thus, the present study provides evidence that the presence of diatoms in spleen tissue may be a reliable indicator of death by drowning.
5.Impacts of Return-to-Work Type and Period on Job Retention in Workers with Occupational Injuries and Diseases
Inchul JEONG ; Jae Bum PARK ; Hyoung Ryoul KIM ; Jin Ha YOON ; Jong Uk WON ; Jaehoon ROH
Journal of Korean Medical Science 2018;33(1):e2-
BACKGROUND: Despite the necessity of job retention in achieving return-to-work (RTW) goals, many workers leave their jobs after returning to work. The objective of this study was to examine the impacts of RTW type and period on job retention in Korean workers with occupational injuries and diseases. METHODS: Data were derived from the Panel Study of Worker's Compensation Insurance, including data from 2,000 systemically sampled workers who had finished recuperation in 2012; three waves of survey data were included in the analyses. Workers who returned to work (n = 1,610) were included in the analysis of the relationship between RTW type and job retention, and 664 workers who returned to their original workplaces were included in the analysis of the relationship between RTW period and job retention. The participants completed a questionnaire, and administrative data were provided by workers' compensation insurance. RESULTS: A Cox proportional-hazards regression analysis showed an increased hazard ratio (HR) for non-retention of 2.66 (95% confidence interval, 2.11–3.35) in reemployed workers compared to that in workers returning to their original workplaces. Among workers returning to their original workplaces, HRs for non-retention were increased in workers with a RTW period of 13–24 months (3.03 [1.52–6.04]) and > 24 months (5.33 [2.14–13.25]) compared to workers with a RTW period of ≤ 3 months. CONCLUSION: RTW type and period were significantly related to job retention, suggesting that policies for promoting job retention rate should be implemented.
Insurance
;
Occupational Diseases
;
Occupational Health
;
Occupational Injuries
;
Return to Work
;
Workers' Compensation
6.The Korean guideline for hepatocellular carcinoma surveillance.
Do Young KIM ; Hyun Jung KIM ; Seung Eun JEONG ; Sang Gyune KIM ; Hyung Joon KIM ; Dong Hyun SINN ; Yong Joo LEE ; Woo Kyoung JEONG ; Kui Son CHOI ; Nae Yun HEO ; Dong Joon KIM ; Young Seok KIM ; Yong Bum KIM ; Yoon Jun KIM ; Hyoung Ryoul KIM ; Minseon PARK ; Chan Wha LEE ; Won Young TAK ; Ji Hye CHUNG ; Soo Young KIM ; Yeol KIM ; Won Chul LEE ; Hong Soo KIM
Journal of the Korean Medical Association 2015;58(5):385-397
Hepatocellular carcinoma (HCC) is one of the major cancers with a high incidence and mortality in Korea. A Korean multidisciplinary collaborative committee consisting of hepatologists, radiologists, epidemiologists and family medicine doctors systematically reviewed clinical practice guidelines in the world and literatures. The level of evidence for each recommendation was assessed and discussed to reach a consensus. Meta-analysis was also conducted to evaluate the grade of recommendation for the five key questions. Several randomized controlled studies and cohort studies showed a survival gain associated with surveillance for those at risk of developing HCC. The target populations for HCC surveillance were identified as hepatitis B virus or hepatitis C virus carriers and cirrhotic patients, since numerous studies revealed that these patients have significantly higher risk of HCC compared with non-infected or non-cirrhotic controls. Individual surveillance strategy according to treatment history or degree of fibrosis in patients with viral hepatitis remains to be settled. Based on several cohort and randomized studies, a surveillance interval of six months was recommend. The starting age of surveillance was determined as 40 years from the epidemiologic data. Although ultrasonography (US) is the mainstay for detection of HCC, its sensitivity is not fully accepted. Measurement of serum alpha-fetoprotein can complement US examination, increasing the sensitivity of HCC detection. The recommendation for HCC surveillance is that those with hepatitis B virus (or hepatitis C virus) infection or cirrhosis should have liver US and serum alpha-fetoprotein measurement every six months from 40 years of age or at the time of diagnosis of cirrhosis.
alpha-Fetoproteins
;
Carcinoma, Hepatocellular*
;
Cohort Studies
;
Complement System Proteins
;
Consensus
;
Diagnosis
;
Fibrosis
;
Health Services Needs and Demand
;
Hepacivirus
;
Hepatitis
;
Hepatitis B virus
;
Hepatitis C
;
Humans
;
Incidence
;
Korea
;
Liver
;
Mortality
;
Ultrasonography
7.Endoscopy versus Open Bursectomy of Lateral Malleolar Bursitis; Comparative Study.
Jae Hyuck CHOI ; Jeong Ryoul KIM ; Dong Hyun KIM ; Woo Chull CHUNG ; Jung Ro YOON ; Seong Rok OH ; Kyung Tai LEE
Journal of Korean Foot and Ankle Society 2011;15(2):92-96
PURPOSE: To compare the result of endoscopic versus open bursectomy in lateral malleolar bursitis, which was not treated conservatively. MATERIALS AND METHODS: Between January 2008 and October 2009, We divided to two groups, endoscopy (group A) 11 cases, open bursectomy (group B) 11 cases. The average follow up period was 15 months (range, 12 to 18), the mean age was 66 (range, 38 to 79). We compared patients satisfaction, complete healing time, operation time, complications and recurrence. RESULTS: Group A had significant difference in terms of the clinical satisfactions, complete healing time. operation time, complications. Group A showed satisfaction (excellent 9, good 2), mean complete healing time 11.9 (8~14) days, operation time 37 (25~45) minutes, 1 case recur. Group B showed satisfaction (excellent 4, good 3, fair 1, poor 3), complete healing time 32.7 (14~98) days, operation time 22 (18~26) minutes. complication were one case of skin necrosis, one case of wound dehiscence, two cases of superficial peroneal nerve injury, no recurrence. Significant advantages of endoscopic method include lower morbidity and rapid wound healing period (p<0.05). CONCLUSION: Endoscopic resection of the lateral malleolar bursitis is a promising technique and shows favourable results compared to the open resection. Significant advantages of this method include lower morbidiy and rapid wound healing.
Animals
;
Ankle
;
Bursitis
;
Endoscopy
;
Follow-Up Studies
;
Humans
;
Necrosis
;
Peroneal Nerve
;
Recurrence
;
Skin
;
Wound Healing
8.Occupational Lung Cancer Surveillance in South Korea, 2006-2009.
Jong Han LEEM ; Hwan Cheol KIM ; Jeong Seon RYU ; Jong Uk WON ; Jai Dong MOON ; Young Chul KIM ; Sang Baek KOH ; Suk Joong YONG ; Soo Geun KIM ; Jae Yong PARK ; Inah KIM ; Jung Il KIM ; Jung Won KIM ; Eui cheol LEE ; Hyoung Ryoul KIM ; Dae Hwan KIM ; Dong Mug KANG ; Yun Chul HONG
Safety and Health at Work 2010;1(2):134-139
OBJECTIVES: The lung cancer mortality in Korea has increased remarkably during the last 20 years, and has been the first leading cause of cancer-related deaths since 2000. The aim of the current study was to examine the time trends of occupational lung cancer and carcinogens exposure during the period 2006-2009 in South Korea, by assessing the proportion of occupational burden. METHODS: We defined occupational lung cancer for surveillance, and developed a reporting protocol and reporting website for the surveillance of occupational lung cancer. The study patients were chosen from 9 participating university hospitals in the following 7 areas: Seoul, Incheon, Wonju, Daejeon, Daegu, Busan, and Gwangju. RESULTS: The combined proportion of definite and probable occupational lung cancer among all lung cancers investigated in this study was 10.0%, 8.6%, 10.7%, and 15.8% in the years 2006 to 2009, respectively, with an average of 11.7% over the four-year study period. The main carcinogens were asbestos, crystalline silica, radon, polyaromatic hydrocarbons (PAHs), diesel exhaust particles, chromium, and nickel. CONCLUSION: We estimated that about 11.7% of the incident lung cancer was preventable. This reveals the potential to considerably reduce lung cancer by intervention in occupational fields.
Asbestos
;
Carcinogens
;
Chromium
;
Crystallins
;
Hospitals, University
;
Humans
;
Hydrocarbons
;
Korea
;
Lung
;
Lung Neoplasms
;
Radon
;
Republic of Korea
;
Silicon Dioxide
;
Vehicle Emissions
9.End Stage Ankle Arthritis with Ankle Instability Patients Treatment Results Using Autograft Ligament Reconstruction with Total Ankle Arthroplasty.
Jae Hyuck CHOI ; Jeong Ryoul KIM ; Dong Hyun KIM ; Woo Chull CHUNG ; Jung Ro YOON ; Eui Dong YEO ; Kyung Tai LEE
Journal of Korean Foot and Ankle Society 2010;14(1):47-52
PURPOSE: We report the clinical and radiographic result of ligament reconstruction using plantaris and total ankle replacement in end-stage ankle arthritis with ankle instability. MATERIALS AND METHODS: The study is based on the 9 cases among total 48 patients of end-stage ankle arthritis that were treated with total ankle prosthesis and ligament reconstruction from 2007 to 2009 at least 12 months follow-up. We evaluated the VAS (Visual analogue scale) pain score, AOFAS (American orthopedic foot and ankle society) score and radiographic measurements. RESULTS: Average age was 59.4 years (53~67 years) old. VAS pain score improved from preoperative average 8.2+/-0.9 (range, 7~10) to 2.7+/-1.7 (range, 0~6) and the AOFAS score improved from 46.4+/-14.6 points (range, 23~69) to 80.1+/-9.3 points (range, 65~95) at final follow-up. Anterior draw test improved 15.2+/-3.4 mm (range, 12~23 mm) to 8.8+/-2.6 mm (range, 6~13mm),varus stress test improved from 13.9+/-4.6degrees (range,10-18degrees) to 6.2+/-4.7degrees (range,2-18degrees) at final follow up. CONCLUSION: Plantaris ligament reconstruction is good option as part of the management of ankle instability with end-stage ankle arthritis. We achieved good clinical and radiographic results.
Animals
;
Ankle
;
Arthritis
;
Arthroplasty
;
Arthroplasty, Replacement, Ankle
;
Exercise Test
;
Follow-Up Studies
;
Foot
;
Humans
;
Ligaments
;
Orthopedics
;
Prostheses and Implants
10.Mandibular bone regeneration using autogenous skin-derived precursor cells with a mixed demineralized bone and fibrin glue scaffold in miniature pigs
June Ho BYUN ; Mun Jeong CHOI ; Young Jin CHOI ; Kyoung Mok SHIM ; Uk Kyu KIM ; Jong Ryoul KIM ; Bong Wook PARK
Journal of the Korean Association of Maxillofacial Plastic and Reconstructive Surgeons 2009;31(3):198-206
Adult
;
Animals
;
Bone Regeneration
;
Bone Transplantation
;
Durapatite
;
Ear
;
Fibrin
;
Fibrin Tissue Adhesive
;
Humans
;
Minerals
;
Osteocalcin
;
Osteogenesis
;
Skin
;
Swine
;
Transplants

Result Analysis
Print
Save
E-mail