1.Ultrasonographic assessment of experimentally induced gastric perforation in beagle dogs
Dongryun NAM ; Taesung HWANG ; Hee Chun LEE
Korean Journal of Veterinary Research 2019;59(3):119-122
The goals of this study were, first, to evaluate the feasibility of inducing gastric perforation with 99% alcohol injection after electrocautery (EA-method), and, second, to observe “enhanced peritoneal stripe sign (EPSS)” and other lesions upon induction of gastric perforation. Six clinically normal beagle dogs were prepared for gastric perforation using endoscopy. After gastric perforation, EPSS and other lesions on ultrasonography were observed eventually (at 0 h, 3 h, day 1, day 2, day 3, day 4, day 5, and day 6). We graded the EPSS depending on its width and number. EPSS was observed until day 4 of the examination in all the 6 dogs. The grades of EPSS were the highest at 3 h and declined gradually. Peritoneal effusion was observed in all dogs at 3 h and on day 1. Regional bright mesenteric fat was confirmed in all dogs on days 3 and 4. In conclusion, gastric perforation can be induced by EA-method. EPSS and peritoneal effusion appear at a very early stage, and regional bright mesenteric fat was identified on days 3 and 4 in almost all dogs with gastric perforation.
Animals
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Ascitic Fluid
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Dogs
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Electrocoagulation
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Endoscopy
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Pneumoperitoneum
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Ultrasonography
2.Bayesian analysis of longitudinal traits in the Korea Association Resource (KARE) cohort
Wonil CHUNG ; Hyunji HWANG ; Taesung PARK
Genomics & Informatics 2022;20(2):e16-
Various methodologies for the genetic analysis of longitudinal data have been proposed and applied to data from large-scale genome-wide association studies (GWAS) to identify single nucleotide polymorphisms (SNPs) associated with traits of interest and to detect SNP-time interactions. We recently proposed a grid-based Bayesian mixed model for longitudinal genetic data and showed that our Bayesian method increased the statistical power compared to the corresponding univariate method and well detected SNP-time interactions. In this paper, we further analyze longitudinal obesity-related traits such as body mass index, hip circumference, waist circumference, and waist-hip ratio from Korea Association Resource data to evaluate the proposed Bayesian method. We first conducted GWAS analyses of cross-sectional traits and combined the results of GWAS analyses through a meta-analysis based on a trajectory model and a random-effects model. We then applied our Bayesian method to a subset of SNPs selected by meta-analysis to further discover SNPs associated with traits of interest and SNP-time interactions. The proposed Bayesian method identified several novel SNPs associated with longitudinal obesity-related traits, and almost 25% of the identified SNPs had significant p-values for SNP-time interactions.
3.The Prevalence and Characteristics of Pre-eruptive Intracoronal Radiolucencies in Children and Adolescents
Younghyun AHN ; Yeonmi YANG ; Jaejoon HWANG ; Taesung JEONG ; Jonghyun SHIN
Journal of Korean Academy of Pediatric Dentistry 2021;48(2):160-167
The purpose of this study was to investigate the prevalence and characteristics of pre-eruptive intracoronal radiolucencies (PEIR) from panoramic radiographs in Korean children and adolescents.
This study examined panoramic radiographs of 3,000 patients aged between 5 and 14 years old who visited ten dental hospitals in Korea. The age and gender of the patients, the tooth type, the number of intracoronal radiolucent lesions, and the location and size of the lesions were recorded.
The overall prevalence of patients with PEIR was 2.5%. The difference in the presence of PEIR between both genders was not significant. Within each tooth type, the mandibular first molar showed highest prevalence of PEIR (29.6%). The central part of the crown was the most frequently observed location of PEIR (56.8%). The size of the PEIR lesions was mostly limited to less than one-third of the thickness of coronal dentin.
4.Novel vertebral computed tomography indices in normal and spinal disorder dogs
Jongsu LIM ; Youngmin YOON ; Taesung HWANG ; Hee Chun LEE
Journal of Veterinary Science 2018;19(2):296-300
This study was carried out to derive and evaluate reference computed tomography (CT)-based indices for normal canine spine. CT and magnetic resonance images were acquired from 12 clinically normal Beagle dogs (normal group) and 50 dogs with 56 spinal disorders (patient group). Image acquisition regions were cervical spine (C2–T1), thoracic spine (T1–T13), and lumbar spine (L1–L7). Measured indices were: the ratios of width to height of the spinal cord including the dura matter (CR) and of the vertebral foramen (FR), and the ratio of the cross-sectional area of the spinal cord to that of the vertebral foramen (CFAR). Reliability analysis was performed to evaluate intermodality agreement. Student's t-tests and receiver operating characteristic curves were used to discriminate the normal and patient groups on CT. Intermodality agreements of the normal and patient groups were acceptable to excellent. The highest discriminating levels of CR at the vertebral body level and the intervertebral disc space level were 1.25 or more and 1.44 or more, respectively. FR and CFAR had the highest discriminating level at the cervical region. This report presents quantitative information on canine spinal morphometry; the obtained indices may be helpful for CT screening of dogs with spinal disorders.
Animals
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Dogs
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Humans
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Intervertebral Disc
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Magnetic Resonance Imaging
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Mass Screening
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ROC Curve
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Spinal Cord
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Spine
5.Ultrasonographic evaluation of skin thickness in small breed dogs with hyperadrenocorticism
Seonghun HEO ; Taesung HWANG ; Hee Chun LEE
Journal of Veterinary Science 2018;19(6):840-845
The purpose of this study was to propose a standard for differentiation between normal dogs and patients with hyperadrenocorticism (HAC) by measuring skin thickness via ultrasonography in small breed dogs. Significant changes in skin thickness of patients treated with prednisolone (PDS) or patients with HAC treated with trilostane were evaluated. Skin thickness was retrospectively measured on three abdominal digital images obtained from small breed dogs weighing < 15 kg that underwent abdominal ultrasonography. Mean skin thickness of normal dogs was 1.03 ± 0.25 mm (mean ± SD). Both the HAC and PDS groups showed significantly thinner skin than that in the normal group. Seven of the 10 HAC patients treated with trilostane had increased skin thickness. The area under the curve value of 0.807 was based on the receiver operating characteristics (ROC) curve for differentiating normal dogs from HAC patients. Sensitivity was 76% and specificity was 73% when skin thickness was less than the 0.83 mm cutoff value. In conclusion, measurement of skin thickness in small breed dogs by using ultrasonography is likely to provide clinical information useful in differentiating HAC patients from normal dogs. However, exposure to PDS, trilostane, and other conditions may have a significant effect on skin thickness.
Adrenocortical Hyperfunction
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Animals
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Dogs
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Humans
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Prednisolone
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Retrospective Studies
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ROC Curve
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Sensitivity and Specificity
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Skin
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Ultrasonography
6.Classification of radiographic lung pattern based on texture analysis and machine learning
Youngmin YOON ; Taesung HWANG ; Hojung CHOI ; Heechun LEE
Journal of Veterinary Science 2019;20(4):e44-
This study evaluated the feasibility of using texture analysis and machine learning to distinguish radiographic lung patterns. A total of 1200 regions of interest (ROIs) including four specific lung patterns (normal, alveolar, bronchial, and unstructured interstitial) were obtained from 512 thoracic radiographs of 252 dogs and 65 cats. Forty-four texture parameters based on eight methods of texture analysis (first-order statistics, spatial gray-level-dependence matrices, gray-level-difference statistics, gray-level run length image statistics, neighborhood gray-tone difference matrices, fractal dimension texture analysis, Fourier power spectrum, and Law's texture energy measures) were used to extract textural features from the ROIs. The texture parameters of each lung pattern were compared and used for training and testing of artificial neural networks. Classification performance was evaluated by calculating accuracy and the area under the receiver operating characteristic curve (AUC). Forty texture parameters showed significant differences between the lung patterns. The accuracy of lung pattern classification was 99.1% in the training dataset and 91.9% in the testing dataset. The AUCs were above 0.98 in the training set and above 0.92 in the testing dataset. Texture analysis and machine learning algorithms may potentially facilitate the evaluation of medical images.
Animals
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Area Under Curve
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Cats
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Classification
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Dataset
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Dogs
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Fourier Analysis
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Fractals
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Lung
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Machine Learning
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Neural Networks (Computer)
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Pattern Recognition, Visual
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Radiography, Thoracic
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Residence Characteristics
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ROC Curve
7.Congenital portal vein aplasia with portocaval shunting in two dogs
Taesung HWANG ; Jonghyun MOON ; Hee Chun LEE
Korean Journal of Veterinary Research 2019;59(3):171-173
Two dogs presented with vomiting and head pressing. In both dogs, a large vessel was revealed in computed tomography (CT) angiography, which was found to leave the portal vein (PV) cranial to the splenomesenteric confluence and enter the pre-hepatic caudal vena cava cranial to the right renal vein. The flow of portal blood to the liver was not identified. Based on CT angiography, the dogs were suspected to have congenital PV aplasia with portocaval shunting. Diagnostic imaging of potential malformations for PV continuation should be conducted before attempting shunt closure.
Angiography
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Animals
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Diagnostic Imaging
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Dogs
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Head
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Liver
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Portal Vein
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Portasystemic Shunt, Surgical
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Renal Veins
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Vomiting
8.Hypertrophic obstructive cardiomyopathy in a Yorkshire Terrier
Taesung HWANG ; Junghyun PARK ; Dongin JUNG ; Hee Chun LEE
Korean Journal of Veterinary Research 2018;58(3):159-162
An 11-year-old, castrated male dog presented with a 3-month history of cough and depression. Auscultation revealed systolic murmur and thoracic radiographs showing enlargement of both the atrium and left ventricle. Echocardiography showed thickened mitral valve and moderate-to-severe left atrial enlargement. Additionally, M-mode echocardiography showed symmetric left ventricular wall thickening and systolic anterior motion of the mitral valve, while Doppler imaging revealed high velocity turbulent flow through the left ventricular outflow tract. Based on echocardiography, this case was diagnosed with hypertrophic obstructive cardiomyopathy. After 5 months, the dog was clinically static in radiography and echocardiography.
Animals
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Auscultation
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Cardiomyopathy, Hypertrophic
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Child
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Cough
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Depression
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Dogs
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Echocardiography
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Heart Ventricles
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Humans
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Male
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Mitral Valve
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Radiography
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Systolic Murmurs
9.Hypertrophic obstructive cardiomyopathy in a Yorkshire Terrier
Taesung HWANG ; Junghyun PARK ; Dongin JUNG ; Hee Chun LEE
Korean Journal of Veterinary Research 2018;58(3):159-162
An 11-year-old, castrated male dog presented with a 3-month history of cough and depression. Auscultation revealed systolic murmur and thoracic radiographs showing enlargement of both the atrium and left ventricle. Echocardiography showed thickened mitral valve and moderate-to-severe left atrial enlargement. Additionally, M-mode echocardiography showed symmetric left ventricular wall thickening and systolic anterior motion of the mitral valve, while Doppler imaging revealed high velocity turbulent flow through the left ventricular outflow tract. Based on echocardiography, this case was diagnosed with hypertrophic obstructive cardiomyopathy. After 5 months, the dog was clinically static in radiography and echocardiography.
10.Development and External Validation of Survival Prediction Model for Pancreatic Cancer Using Two Nationwide Databases: Surveillance, Epidemiology and End Results (SEER) and Korea Tumor Registry System-Biliary Pancreas (KOTUS-BP)
Jae Seung KANG ; Lydia MOK ; Jin Seok HEO ; In Woong HAN ; Sang Hyun SHIN ; Yoo-Seok YOON ; Ho-Seong HAN ; Dae Wook HWANG ; Jae Hoon LEE ; Woo Jung LEE ; Sang Jae PARK ; Joon Seong PARK ; Yonghoon KIM ; Huisong LEE ; Young-Dong YU ; Jae Do YANG ; Seung Eun LEE ; Il Young PARK ; Chi-Young JEONG ; Younghoon ROH ; Seong-Ryong KIM ; Ju Ik MOON ; Sang Kuon LEE ; Hee Joon KIM ; Seungyeoun LEE ; Hongbeom KIM ; Wooil KWON ; Chang-Sup LIM ; Jin-Young JANG ; Taesung PARK
Gut and Liver 2021;15(6):912-921
Background/Aims:
Several prediction models for evaluating the prognosis of nonmetastatic resected pancreatic ductal adenocarcinoma (PDAC) have been developed, and their performances were reported to be superior to that of the 8th edition of the American Joint Committee on Cancer (AJCC) staging system. We developed a prediction model to evaluate the prognosis of resected PDAC and externally validated it with data from a nationwide Korean database.
Methods:
Data from the Surveillance, Epidemiology and End Results (SEER) database were utilized for model development, and data from the Korea Tumor Registry System-Biliary Pancreas (KOTUS-BP) database were used for external validation. Potential candidate variables for model development were age, sex, histologic differentiation, tumor location, adjuvant chemotherapy, and the AJCC 8th staging system T and N stages. For external validation, the concordance index (C-index) and time-dependent area under the receiver operating characteristic curve (AUC) were evaluated.
Results:
Between 2004 and 2016, data from 9,624 patients were utilized for model development, and data from 3,282 patients were used for external validation. In the multivariate Cox proportional hazard model, age, sex, tumor location, T and N stages, histologic differentiation, and adjuvant chemotherapy were independent prognostic factors for resected PDAC. After an exhaustive search and 10-fold cross validation, the best model was finally developed, which included all prognostic variables. The C-index, 1-year, 2-year, 3-year, and 5-year time-dependent AUCs were 0.628, 0.650, 0.665, 0.675, and 0.686, respectively.
Conclusions
The survival prediction model for resected PDAC could provide quantitative survival probabilities with reliable performance. External validation studies with other nationwide databases are needed to evaluate the performance of this model.