1.Development and External Validation of a Deep Learning Algorithm for Prognostication of Cardiovascular Outcomes
In Jeong CHO ; Ji Min SUNG ; Hyeon Chang KIM ; Sang Eun LEE ; Myeong Hun CHAE ; Maryam KAVOUSI ; Oscar L RUEDA-OCHOA ; M Arfan IKRAM ; Oscar H FRANCO ; James K MIN ; Hyuk Jae CHANG
Korean Circulation Journal 2020;50(1):72-84
BACKGROUND AND OBJECTIVES: We aim to explore the additional discriminative accuracy of a deep learning (DL) algorithm using repeated-measures data for identifying people at high risk for cardiovascular disease (CVD), compared to Cox hazard regression.METHODS: Two CVD prediction models were developed from National Health Insurance Service-Health Screening Cohort (NHIS-HEALS): a Cox regression model and a DL model. Performance of each model was assessed in the internal and 2 external validation cohorts in Koreans (National Health Insurance Service-National Sample Cohort; NHIS-NSC) and in Europeans (Rotterdam Study). A total of 412,030 adults in the NHIS-HEALS; 178,875 adults in the NHIS-NSC; and the 4,296 adults in Rotterdam Study were included.RESULTS: Mean ages was 52 years (46% women) and there were 25,777 events (6.3%) in NHIS-HEALS during the follow-up. In internal validation, the DL approach demonstrated a C-statistic of 0.896 (95% confidence interval, 0.886–0.907) in men and 0.921 (0.908–0.934) in women and improved reclassification compared with Cox regression (net reclassification index [NRI], 24.8% in men, 29.0% in women). In external validation with NHIS-NSC, DL demonstrated a C-statistic of 0.868 (0.860–0.876) in men and 0.889 (0.876–0.898) in women, and improved reclassification compared with Cox regression (NRI, 24.9% in men, 26.2% in women). In external validation applied to the Rotterdam Study, DL demonstrated a C-statistic of 0.860 (0.824–0.897) in men and 0.867 (0.830–0.903) in women, and improved reclassification compared with Cox regression (NRI, 36.9% in men, 31.8% in women).CONCLUSIONS: A DL algorithm exhibited greater discriminative accuracy than Cox model approaches.TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02931500
Adult
;
Artificial Intelligence
;
Cardiovascular Diseases
;
Cohort Studies
;
Female
;
Follow-Up Studies
;
Humans
;
Insurance, Health
;
Learning
;
Male
;
Mass Screening
;
National Health Programs
2.Increment of Serum Free Light Chain Kappa/Lambda Ratio in Patients with Renal Dysfunction.
Jae Won JUNG ; Myeong A CHEONG ; Hyun Ju KIM ; Sae Hwan KIM ; Ae chin OH ; Jin Kyung LEE ; Young Jun HONG ; Yoon Hwan CHANG
Laboratory Medicine Online 2019;9(1):12-16
BACKGROUND: Since free light chain (FLC) is metabolized in the kidney, serum FLC concentration and kappa/lambda ratio are increased in patients with decreased renal function, even in the absence of monoclonal protein. In this study, we measured serum FLC levels to investigate the change in kappa/lambda ratios in relation to the severity of renal dysfunction. METHODS: Serum FLC concentrations were measured in 92 archived serum samples from patients diagnosed with chronic kidney disease using the Freelite assay (The Binding Site Group Ltd., UK), and kappa/lambda ratios were calculated. Serum creatinine levels were assayed to calculate estimated glomerular filtration rate (eGFR), and patients were divided into subgroups according to Kidney Disease Improving Global Outcomes (KDIGO) guidelines. We analyzed the difference in serum FLC levels and kappa/lambda ratios between subgroups. RESULTS: Serum FLC levels and kappa/lambda ratios increased depending on the severity of renal dysfunction. When patients were classified by setting cut-off value of eGFR as 60 mL/min/1.73 m2 (group A: eGFR ≥60 mL/min/1.73 m2, group B: < 60 mL/min/1.73 m2), the kappa/lambda ratio of group B was significantly higher than that of group A (group B: 1.60±0.46 vs. group A: 1.35±0.27, P=0.018). Serum FLC kappa/lambda ratios were within the previously determined renal reference interval (0.37–3.1). CONCLUSIONS: When interpreting results of serum FLC kappa/lambda ratio, renal function status should be considered in addition to hematological findings. If renal function deteriorates, a wider renal reference interval is preferred instead of the usual reference interval.
Binding Sites
;
Creatinine
;
Glomerular Filtration Rate
;
Humans
;
Kidney
;
Kidney Diseases
;
Renal Insufficiency, Chronic
3.Beta-Blockers in Patients with Heart Failure with Preserved Ejection Fraction: Results from The Korea Acute Heart Failure (KorAHF) Registry
Sung Hwan KIM ; Sung Cheol YUN ; Jin Joo PARK ; Sang Eun LEE ; Eun Seok JEON ; Jae Joong KIM ; Myeong Chan CHO ; Shung Chull CHAE ; Seok Min KANG ; Dong Ju CHOI ; Byung Su YOO ; Kye Hun KIM ; Byung Hee OH ; Sang Hong BAEK ;
Korean Circulation Journal 2019;49(3):238-248
BACKGROUND AND OBJECTIVES: Beta-blockers are indicated in patients with heart failure (HF) with reduced ejection fraction. However, their efficacy in patients with HF with preserved ejection fraction (HFpEF) is uncertain. We investigated the hypothesis that beta-blockers are associated with reduced adverse events in patients with HFpEF. METHODS: The Korea Acute Heart Failure (KorAHF) is a prospective observational multicentre cohort study. The 5,625 patients hospitalized for acute HF syndrome in 10 tertiary university hospitals across the country have been consecutively enrolled between March 2011 and February 2014. Of these patients, 2,152 patients with HFpEF (ejection fraction ≥40%) were investigated. The primary outcome was all-cause mortality according to beta-blocker use. RESULTS: During a median follow-up duration of 807 days, 702 patients died. In Cox proportional hazards model beta-blocker use was associated with a 14% reduced all-cause death (hazard ratio [HR], 0.86; 95% confidence interval [CI], 0.75–0.98), but not with reduce rehospitalization (HR, 1.03; 95% CI, 0.85–1.27). In the propensity-score matched population, beta-blockers were also associated with reduced all-cause death (HR, 0.80; 95% CI, 0.69–0.94) but not with reduced rehospitalization (HR, 1.08; 95% CI, 0.87–1.33). CONCLUSIONS: In Korean patients with HFpEF, use of beta-blockers is associated with reduced all-cause death but not with reduced rehospitalization.
Cohort Studies
;
Diastole
;
Follow-Up Studies
;
Heart Failure
;
Heart
;
Hospitals, University
;
Humans
;
Korea
;
Mortality
;
Proportional Hazards Models
;
Prospective Studies
4.Prognostic Implication of Ventricular Conduction Disturbance Pattern in Hospitalized Patients with Acute Heart Failure Syndrome
Ji Hyun LEE ; Jin Joo PARK ; Youngjin CHO ; Il Young OH ; Byung Su YOO ; Jae Joong KIM ; Kye Hun KIM ; Seok Min KANG ; Sang Hong BAEK ; Eun Seok JEON ; Myeong Chan CHO ; Shung Chull CHAE ; Byung Hee OH ; Dong Ju CHOI
Korean Circulation Journal 2019;49(7):602-611
BACKGROUND AND OBJECTIVES: Conflicting data exist regarding the prognostic implication of ventricular conduction disturbance pattern in patients with heart failure (HF). This study investigated the prognostic impact of ventricular conduction pattern in hospitalized patients with acute HF. METHODS: Data from the Korean Acute Heart Failure registry were used. Patients were categorized into four groups: narrow QRS (<120 ms), right bundle branch block (RBBB), left bundle branch block (LBBB), and nonspecific intraventricular conduction delay (NICD). The NICD was defined as prolonged QRS (≥120 ms) without typical features of LBBB or RBBB. The primary endpoint was the composite of all-cause mortality or rehospitalization for HF aggravation within 1 year after discharge. RESULTS: This study included 5,157 patients. The primary endpoint occurred in 39.7% of study population. The LBBB group showed the highest incidence of primary endpoint followed by NICD, RBBB, and narrow QRS groups (52.5% vs. 49.7% vs. 44.4% vs. 37.5%, p<0.001). In a multivariable Cox-proportional hazards regression analysis, LBBB and NICD were associated with 39% and 28% increased risk for primary endpoint (LBBB hazard ratio [HR], 1.392; 95% confidence interval [CI], 1.152–1.681; NICD HR, 1.278; 95% CI, 1.074–1.520) compared with narrow QRS group. The HR of RBBB for the primary endpoint was 1.103 (95% CI, 0.915–1.329). CONCLUSIONS: LBBB and NICD were independently associated with an increased risk of 1-year adverse event in hospitalized patients with HF, whereas the prognostic impacts of RBBB were limited. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01389843
Bundle-Branch Block
;
Heart Failure
;
Heart
;
Humans
;
Incidence
;
Mortality
;
Prognosis
5.Recurrent Painful Ophthalmoplegic Neuropathy: a Case Report
Jae Hwi PARK ; Ho Kyu LEE ; Myeong Ju KOH ; Jung Hwan OH ; Sung Joo PARK
Investigative Magnetic Resonance Imaging 2019;23(2):172-174
Upon review, it is noted that recurrent painful ophthalmoplegic neuropathy (RPON) is a rare neurological syndrome characterized by recurrent unilateral headaches and painful ophthalmoplegia of the ipsilateral oculomotor nerve. As seen on brain MRI, thickening and enhancement of the oculomotor cranial nerve can be observed in these cases. We experienced a case of RPON in an adult patient who showed thickening and enhancement of the oculomotor nerve on gadolinium-enhanced 3D-FLAIR image. The authors report a case of RPON with a review of the literature.
Adult
;
Brain
;
Cranial Nerves
;
Headache
;
Humans
;
Magnetic Resonance Imaging
;
Oculomotor Nerve
;
Oculomotor Nerve Diseases
;
Ophthalmoplegia
;
Paralysis
6.Early Phase of Achalasia Manifested as an Esophageal Subepithelial Tumor
Jong Hwa LEE ; Young Jae LEE ; Jong Myeong LEE ; Myoung Jin JU ; Min A YANG ; Myung Woo CHOI ; So Hee YUN
The Korean Journal of Gastroenterology 2019;74(2):110-114
The Chicago classification (CC) defines an esophagogastric junction outflow obstruction (EGJOO) as the presence of several instances of intact or weak peristalsis, elevated median integrated relaxation pressure above 15 mmHg, and a discrepancy from the criteria of achalasia. The revised CC addresses the potential etiology of EGJOO, including the early forms of achalasia, mechanical obstruction, esophageal wall stiffness, or manifestation of hiatal hernia. A 58-year-old woman visited the Presbyterian Medical Center with swallowing difficulty. The patient underwent a high resolution manometry (HRM) examination and was diagnosed with EGJOO. Chest CT was performed to exclude a mechanical obstruction as a cause, and CT revealed a subepithelial tumor (SET) at the upper part of the esophagogastric junction. Therefore, laparoscopic surgery was performed and eccentric muscular hypertrophy of the distal esophagus was observed. Longitudinal myotomy and Dor fundoplication were also performed. The histology findings of the surgical specimens were consistent with achalasia. This paper reports a case of early achalasia that was finally diagnosed by the histology findings, but was initially diagnosed as EGJOO using HRM and misdiagnosed as SET in the image study.
Classification
;
Deglutition
;
Esophageal Achalasia
;
Esophagogastric Junction
;
Esophagus
;
Female
;
Fundoplication
;
Hernia, Hiatal
;
Humans
;
Hypertrophy
;
Laparoscopy
;
Manometry
;
Middle Aged
;
Peristalsis
;
Protestantism
;
Relaxation
;
Tomography, X-Ray Computed
7.Prevalence of Intestinal Helminth Infections in Dogs and Two Species of Wild Animals from Samarkand Region of Uzbekistan
Tai Soon YONG ; Kyu Jae LEE ; Myeong Heon SHIN ; Hak Sun YU ; Uktamjon SUVONKULOV ; Turycin Bladimir SERGEEVICH ; Azamat SHAMSIEV ; Gab Man PARK
The Korean Journal of Parasitology 2019;57(5):549-552
This study aimed to determine the prevalence of intestinal helminth parasitic infections and associated risk factors for the human infection among the people of Samarkand, Uzbekistan. Infection status of helminths including Echinococcus granulosus was surveyed in domestic and wild animals from 4 sites in the Samarkand region, Uzbekistan during 2015–2018. Fecal samples of each animal were examined with the formalin-ether sedimentation technique and the recovery of intestinal helminths was performed with naked eyes and a stereomicroscope in total 1,761 animals (1,755 dogs, 1 golden jackal, and 5 Corsac foxes). Total 658 adult worms of E. granulosus were detected in 28 (1.6%) dogs and 1 (100%) golden jackal. More than 6 species of helminths, i.e., Taenia hydatigena, Dipylidium caninum, Diplopylidium nolleri, Mesocestoides lineatus, Toxocara canis, and Trichuris vulpis, were found from 18 (1.0%) dogs. Six (T. hydatigena, Toxascaris leonina, Alaria alata, Uncinaria stenocephala, D. caninum, and M. lineatus) and 2 (D. nolleri and M. lineatus) species of helminths were also detected from 5 Corsac foxes and 1 golden jackal, respectively. Taeniid eggs were found in 2 (20%) out of 10 soil samples. In the present study, it was confirmed that the prevalences of helminths including E. granulosus are not so high in domestic and wild animals. Nevertheless, the awareness on the zoonotic helminth infections should be continuously maintained in Uzbekistan for the prevention of human infection.
Adult
;
Ancylostomatoidea
;
Animals
;
Animals, Wild
;
Dogs
;
Echinococcus granulosus
;
Eggs
;
Foxes
;
Helminths
;
Humans
;
Jackals
;
Mesocestoides
;
Ovum
;
Prevalence
;
Risk Factors
;
Soil
;
Taenia
;
Toxascaris
;
Toxocara canis
;
Trichuris
;
Uzbekistan
8.Inter-observer Reproducibility in the Pathologic Diagnosis of Gastric Intraepithelial Neoplasia and Early Carcinoma in Endoscopic Submucosal Dissection Specimens: A Multi-center Study
Joon Mee KIM ; Jin Hee SOHN ; Mee Yon CHO ; Woo Ho KIM ; Hee Kyung CHANG ; Eun Sun JUNG ; Myeong Cherl KOOK ; So Young JIN ; Yang Seok CHAE ; Young Soo PARK ; Mi Seon KANG ; Hyunki KIM ; Jae Hyuk LEE ; Do Youn PARK ; Kyoung Mee KIM ; Hoguen KIM ; Young Ju SUH ; Sang Yong SEOL ; Hwoon Yong JUNG ; Deuck Hwa KIM ; Na Rae LEE ; Seung Hee PARK ; Ji Hye YOU
Cancer Research and Treatment 2019;51(4):1568-1577
PURPOSE: The diagnostic criteria of gastric intraepithelial neoplasia (IEN) are controversial across the world. We investigated how many discrepancies occur in the pathologic diagnosis of IEN and early gastric carcinoma in endoscopic submucosal dissection (ESD) specimens, and evaluated the reasons of the discordance. MATERIALS AND METHODS: We retrospectively reviewed 1,202 ESD specimens that were originally diagnosed as gastric IEN and early carcinoma at 12 institutions. RESULTS: The final consensus diagnosis of carcinoma were 756 cases, which were originally 692 carcinomas (91.5%), 43 high-grade dysplasias (5.7%), 20 low-grade dysplasias (2.6%), and 1 others (0.1%), respectively. High- and low-grade dysplasia were finally made in 63 and 342 cases, respectively. The diagnostic concordance with the consensus diagnosis was the highest for carcinoma (91.5%), followed by low-grade dysplasia (86.3%), others (63.4%) and high-grade dysplasia (50.8%). The general kappa value was 0.83, indicating excellent concordance. The kappa values of individual institutions ranged from 0.74 to 1 and correlated with the proportion of carcinoma cases. The cases revised to a final diagnosis of carcinoma exhibited both architectural abnormalities and cytologic atypia. The main differential points between low- and high-grade dysplasias were the glandular distribution and glandular shape. Additional features such as the glandular axis, surface maturation, nuclear stratification and nuclear polarity were also important. CONCLUSION: The overall concordance of the diagnosis of gastric IEN and early carcinoma in ESD specimens was excellent. It correlated with the proportion of carcinoma cases, demonstrating that the diagnostic criteria for carcinoma are more reproducible than those for dysplasia.
Consensus
;
Diagnosis
;
Retrospective Studies
;
Stomach Neoplasms
9.Analysis of Changes in Retinal Photoreceptors Using Optical Coherence Tomography in a Feline Model of Iodoacetic Acid-induced Retinal Degeneration
Gwang Myeong NOH ; Jae Wan LIM ; Myung Shin LEE ; Seung Uk LEE ; Sang Joon LEE
Korean Journal of Ophthalmology 2019;33(6):547-556
PURPOSE: We investigated structural changes in the retina by using optical coherence tomography (OCT) in a feline model of retinal degeneration using iodoacetic acid (IAA).METHODS: We examined 22 eyes of 11 felines over 2 years of age. The felines had fasted for 12 hours and were intravenously injected with IAA 20 mg/kg of body weight. OCT (Spectralis OCT) was performed at the point where the ends of the retinal vessels collected in the lateral direction from the optic nerve head and area centralis. Similarly, OCT was performed four times at 1-week intervals following injections, at which point the felines were sacrificed and histologic examinations were performed. Using OCT, the thickness of each layer of the retina was measured.RESULTS: The average body weight of the three male and eight female felines investigated in this study was 1.61 ± 0.19 kg. The mean total retinal thickness of the felines before injection was 221.32 ± 9.82 µm, with a significant decrease in the retinal thickness at 2, 3, and 4 weeks following injections of 186.41 ± 35.42, 174.56 ± 31.94, and 175.35 ± 33.84 µm, respectively (p = 0.028, 0.027, and 0.027, respectively). The thickness of the outer nuclear layer was 57.49 ± 8.03 µm before injection and 29.26 ± 17.87, 25.62 ± 13.88, and 31.60 ± 18.38 µm at 2, 3, and 4 weeks, respectively, after injection (p = 0.028, 0.028, 0.046, respectively).CONCLUSIONS: In a feline model of retinal degeneration using IAA, the total retinal thickness and the thickness of the outer nuclear layer were shown to decrease significantly on OCT.
Angiography
;
Body Weight
;
Female
;
Humans
;
Iodoacetic Acid
;
Male
;
Optic Disk
;
Photoreceptor Cells, Vertebrate
;
Retina
;
Retinal Degeneration
;
Retinal Vessels
;
Retinaldehyde
;
Tomography, Optical Coherence
10.Intraindividual Comparison between Gadoxetate-Enhanced Magnetic Resonance Imaging and Dynamic Computed Tomography for Characterizing Focal Hepatic Lesions: A Multicenter, Multireader Study
Chansik AN ; Chang Hee LEE ; Jae Ho BYUN ; Min Hee LEE ; Woo Kyoung JEONG ; Sang Hyun CHOI ; Do Young KIM ; Young Suk LIM ; Young Seok KIM ; Ji Hoon KIM ; Moon Seok CHOI ; Myeong Jin KIM
Korean Journal of Radiology 2019;20(12):1616-1626
OBJECTIVE: To compare the diagnostic accuracy of dynamic computed tomography (CT) and gadoxetate-enhanced magnetic resonance imaging (MRI) for characterization of hepatic lesions by using the Liver Imaging Reporting and Data System (LI-RADS) in a multicenter, off-site evaluation.MATERIALS AND METHODS: In this retrospective multicenter study, we evaluated 231 hepatic lesions (114 hepatocellular carcinomas [HCCs], 58 non-HCC malignancies, and 59 benign lesions) confirmed histologically in 217 patients with chronic liver disease who underwent both gadoxetate-enhanced MRI and dynamic CT at one of five tertiary hospitals. Four radiologists at different institutes independently reviewed all MR images first and the CT images 4 weeks later. They evaluated the major and ancillary imaging features and categorized each hepatic lesion according to the LI-RADS v2014. Diagnostic performance was calculated and compared using generalized estimating equations.RESULTS: MRI showed higher sensitivity and accuracy than CT for diagnosing hepatic malignancies; the pooled sensitivities, specificities, and accuracies for categorizing LR-5/5V/M were 59.0% vs. 72.4% (CT vs. MRI; p < 0.001), 83.5% vs. 83.9% (p = 0.906), and 65.3% vs. 75.3% (p < 0.001), respectively. CT and MRI showed comparable capabilities for differentiating between HCC and other malignancies, with pooled accuracies of 79.9% and 82.4% for categorizing LR-M, respectively (p = 0.139).CONCLUSION: Gadoxetate-enhanced MRI showed superior accuracy for categorizing LR-5/5V/M in hepatic malignancies in comparison with dynamic CT. Both modalities had comparable accuracies for distinguishing other malignancies from HCC.
Academies and Institutes
;
Carcinoma, Hepatocellular
;
Contrast Media
;
Humans
;
Information Systems
;
Liver
;
Liver Diseases
;
Magnetic Resonance Imaging
;
Retrospective Studies
;
Tertiary Care Centers

Result Analysis
Print
Save
E-mail