Objective: To develop and evaluate a deep learning model for automated segmentation and detection of bone metastasis on spinal MRI. Materials and Methods: We included whole spine MRI scans of adult patients with bone metastasis: 662 MRI series from 302 patients (63.5 ± 11.5 years; male:female, 151:151) from three study centers obtained between January 2015 and August 2021 for training and internal testing (random split into 536 and 126 series, respectively) and 49 MRI series from 20 patients (65.9 ± 11.5 years; male:female, 11:9) from another center obtained between January 2018 and August 2020 for external testing. Three sagittal MRI sequences, including non-contrast T1-weighted image (T1), contrast-enhanced T1-weighted Dixon fat-only image (FO), and contrast-enhanced fat-suppressed T1-weighted image (CE), were used. Seven models trained using the 2D and 3D U-Nets were developed with different combinations (T1, FO, CE, T1 + FO, T1 + CE, FO + CE, and T1 + FO + CE). The segmentation performance was evaluated using Dice coefficient, pixel-wise recall, and pixel-wise precision. The detection performance was analyzed using per-lesion sensitivity and a free-response receiver operating characteristic curve. The performance of the model was compared with that of five radiologists using the external test set. Results: The 2D U-Net T1 + CE model exhibited superior segmentation performance in the external test compared to the other models, with a Dice coefficient of 0.699 and pixel-wise recall of 0.653. The T1 + CE model achieved per-lesion sensitivities of 0.828 (497/600) and 0.857 (150/175) for metastases in the internal and external tests, respectively. The radiologists demonstrated a mean per-lesion sensitivity of 0.746 and a mean per-lesion positive predictive value of 0.701 in the external test. Conclusion The deep learning models proposed for automated segmentation and detection of bone metastases on spinal MRI demonstrated high diagnostic performance.

Background/Aims: The aim of this study was to investigate long-term post-discontinuation outcomes in patients with rheumatoid arthritis (RA) who had been treated with tumor necrosis factor-α inhibitors (TNF-αi) which was then discontinued. Methods: Sixty Korean patients with RA who participated in a 5-year GO-BEFORE and GO-FORWARD extension trials were included in this retrospective study. Golimumab was deliberately discontinued after the extension study (baseline). Patients were then followed by their rheumatologists. We reviewed their medical records for 2 years (max 28 months) following golimumab discontinuation. Patients were divided into a maintained benefit (MB) group and a loss-of-benefit (LB) group based on treatment pattern after golimumab discontinuation. The LB group included patients whose conventional disease-modifying antirheumatic drug(s) were stepped-up or added/switched (SC) and those who restarted biologic therapy (RB). Results: The mean age of patients at baseline was 56.5 years and 55 (91.7%) were females. At the end of follow-up, 23 (38.3%) patients remained in the MB group. In the LB group, 75.7% and 24.3% were assigned into SC and RB subgroups, respectively. Fifty percent of patients lost MB after 23.3 months. Demographics and clinical variables at baseline were comparable between MB and LB groups except for age, C-reactive protein level, and corticosteroid use. Restarting biologic therapy was associated with swollen joint count (adjusted hazard ratio [HR], 1.90; 95% confidence interval [CI], 1.01 to 3.55) and disease duration (adjusted HR, 1.12; 95% CI, 1.02 to 1.23) at baseline. Conclusions Treatment strategies after discontinuing TNF-αi are needed to better maintain disease control and quality of life of patients with RA.

Background and Objectives: Leaflet thrombosis after transcatheter aortic valve replacement (TAVR) has been reported recently, whereas thrombus formation in sinus of Valsalva has yet to be fully evaluated. This study describes clinical and cardiac computed tomography (CT) findings of patients with sinus of Valsalva thrombosis. Methods: Between March 2011 and Aug 2019, 192 patients underwent cardiac CT after TAVR. After a retrospective review of CT images, 9 patients (82 years, male:female=2:7) who had sinus of Valsalva thrombosis identified by cardiac CT were selected for this study. Patient demographics, interval between TAVR and cardiac CT scan, location and CT attenuation of sinus of Valsalva thrombosis, and presence of concurrent leaflet thrombosis were evaluated. Results: The median interval between TAVR and cardiac CT was 11 days. Sinus of Valsalva thrombosis was frequently detected in the non-coronary sinus (89%, 8/9), and predominantly located in the bottom of the sinus extending upward towards the sinotubular junction. Three patients had concomitant leaflet thrombosis, and 3 patients had subclinical embolic stroke noted on brain magnetic resonance imaging. All patients had been prescribed aspirin and clopidogrel after TAVR for at least 6 months without anticoagulants. Conclusions Cardiac CT after TAVR can detect sinus of Valsalva thrombosis, and attention should be paid to this potential source of subsequent systemic embolization.

Objectives: The purpose of the present study was to examine the relationship between the chronotype and the burnout, so we investigated the mediating effects of the mediators such as perceived stress, stress response, and depression. Methods: Employees working at Incheon Customs conducted a mental health self-examination through the internet. Among them, 174 people who agreed to the mental health survey participated in the study. Participants completed questionnaires including Composite Scale of Morningness (CSM), Center for Epidemiological Studies-Depression Scale (CES-D), Perceived Stress Scale (PSS), Stress Response Inventory (SRI), Maslach Burnout Inventory-General Survey (MBI-GS). Results: Our results showed a higher degree of CES-D, SRI, exhaustion, and cynicism in evening and intermediate type compared to morning type, and a higher degree of professional efficacy in morning type compared to intermediate type. CSM was shown to have a direct effect on exhaustion and indirect effect through CES-D and SRI. CSM also had a direct effect on professional efficacy and had an indirect effect through the CES-D. However, CSM was found to have only indirect effects through the SRI for Cynicism. Conclusions In this study, individuals with evening type tend to experience a high degree of burnout (exhaustion, cynicism and professional efficacy) through the mediation effect of depression and stress response. Further study is necessary to reveal the effect of management of the depression and stress response in the employee with evening type.

Objectives: The purpose of the present study was to examine the relationship between the chronotype and the burnout, so we investigated the mediating effects of the mediators such as perceived stress, stress response, and depression. Methods: Employees working at Incheon Customs conducted a mental health self-examination through the internet. Among them, 174 people who agreed to the mental health survey participated in the study. Participants completed questionnaires including Composite Scale of Morningness (CSM), Center for Epidemiological Studies-Depression Scale (CES-D), Perceived Stress Scale (PSS), Stress Response Inventory (SRI), Maslach Burnout Inventory-General Survey (MBI-GS). Results: Our results showed a higher degree of CES-D, SRI, exhaustion, and cynicism in evening and intermediate type compared to morning type, and a higher degree of professional efficacy in morning type compared to intermediate type. CSM was shown to have a direct effect on exhaustion and indirect effect through CES-D and SRI. CSM also had a direct effect on professional efficacy and had an indirect effect through the CES-D. However, CSM was found to have only indirect effects through the SRI for Cynicism. Conclusions In this study, individuals with evening type tend to experience a high degree of burnout (exhaustion, cynicism and professional efficacy) through the mediation effect of depression and stress response. Further study is necessary to reveal the effect of management of the depression and stress response in the employee with evening type.

In recent years, the taeniasis has been rarely reported in the Republic of Korea (Korea). But in this study, we intend to report 4 taeniasis cases caused by Taenia saginata during a 5-month period (February to June 2018) at a unversity hospital in Gwangju, Korea. Worm samples (proglottids) discharged from all cases were identified by phenotypic and molecular diagnostics. Mitochondrial cytochrome c oxidase subunit I sequences showed 99.4–99.9% identity with T. saginata but, differed by 4% from T. asiatica and by 7% from T. multiceps, respectively. We found that tapeworms in 2 cases (Cases 2 and 3) yielded exactly the same sequences between them, which differed from those in Cases 1 and 4, suggesting intra-species variation in tapeworms. These taeniasis cases by T. saginata infection in this study, which occurred within a limited time period and region, suggest the possibility of a mini-outbreak. This study highlights the need for further epidemiological investigation of potentially overlooked cases of T. saginata infection in Korea.
Cestoda ; Electron Transport Complex IV ; Gwangju ; Korea ; Pathology, Molecular ; Republic of Korea ; Taenia saginata ; Taeniasis

BACKGROUND AND PURPOSE: Decreasing the time delay for thrombolysis, including intravenous thrombolysis (IVT) with tissue plasminogen activator and intra-arterial thrombectomy (IAT), is critical for decreasing the morbidity and mortality of patients experiencing acute stroke. We aimed to decrease the in-hospital delay for both IVT and IAT through a multidisciplinary approach that is feasible 24 h/day. METHODS: We implemented the Stroke Alert Team (SAT) on May 2, 2016, which introduced hospital-initiated ambulance prenotification and reorganized in-hospital processes. We compared the patient characteristics, time for each step of the evaluation and thrombolysis, thrombolysis rate, and post-thrombolysis intracranial hemorrhage from January 2014 to August 2016. RESULTS: A total of 245 patients received thrombolysis (198 before SAT; 47 after SAT). The median door-to-CT, door-to-MRI, and door-to-laboratory times decreased to 13 min, 37.5 min, and 8 min, respectively, after SAT implementation (P<0.001). The median door-to-IVT time decreased from 46 min (interquartile range [IQR] 36–57 min) to 20.5 min (IQR 15.8–32.5 min; P<0.001). The median door-to-IAT time decreased from 156 min (IQR 124.5–212.5 min) to 86.5 min (IQR 67.5–102.3 min; P<0.001). The thrombolysis rate increased from 9.8% (198/2,012) to 15.8% (47/297; P=0.002), and the post-thrombolysis radiological intracranial hemorrhage rate decreased from 12.6% (25/198) to 2.1% (1/47; P=0.035). CONCLUSIONS: SAT significantly decreased the in-hospital delay for thrombolysis, increased thrombolysis rate, and decreased post-thrombolysis intracranial hemorrhage. Time benefits of SAT were observed for both IVT and IAT and during office hours and after-hours.
Ambulances ; Cerebral Infarction ; Humans ; Intracranial Hemorrhages ; Mortality ; Stroke* ; Thrombectomy ; Thrombolytic Therapy ; Tissue Plasminogen Activator

OBJECTIVE: To evaluate T2 relaxation time change using axial T2 mapping in a rabbit degenerated disc model and determine the most correlated variable with histologic score among T2 relaxation time, disc height index, and Pfirrmann grade. MATERIALS AND METHODS: Degenerated disc model was made in 4 lumbar discs of 11 rabbits (n = 44) by percutaneous annular puncture with various severities of an injury. Lumbar spine lateral radiograph, MR T2 sagittal scan and MR axial T2 mapping were obtained at baseline and 2 weeks and 4 weeks after the injury in 7 rabbits and at baseline and 2 weeks, 4 weeks, and 6 weeks after the injury in 4 rabbits. Generalized estimating equations were used for a longitudinal analysis of changes in T2 relaxation time in degenerated disc model. T2 relaxation time, disc height index and Pfirrmann grade were correlated with the histologic scoring of disc degeneration using Spearman's rho test. RESULTS: There was a significant difference in T2 relaxation time between uninjured and injured discs after annular puncture. Progressive decrease in T2 relaxation time was observed in injured discs throughout the study period. Lower T2 relaxation time was observed in the more severely injured discs. T2 relaxation time showed the strongest inverse correlation with the histologic score among the variables investigated (r = -0.811, p < 0.001). CONCLUSION: T2 relaxation time measured with axial T2 mapping in degenerated discs is a potential method to assess disc degeneration.
Animals ; Disease Models, Animal ; Intervertebral Disc/injuries/*pathology ; Intervertebral Disc Degeneration/*pathology ; Lumbar Vertebrae/*pathology ; Magnetic Resonance Imaging/*methods ; Male ; Punctures ; Rabbits

OBJECTIVE: The purpose of this study was to evaluate the reliability of a new magnetic resonance imaging (MRI) grading system for cervical neural foraminal stenosis (NFS). MATERIALS AND METHODS: Cervical NFS at bilateral C4/5, C5/6, and C6/7 was classified into the following three grades based on the T2-weighted axial images: Grade 0 = absence of NFS, with the narrowest width of the neural foramen greater than the width of the extraforaminal nerve root (EFNR); Grade 1 = the narrowest width of the neural foramen the same or less than (but more than 50% of) the width of the EFNR; Grade 2 = the width of the neural foramen the same or less than 50% of the width of the EFNR. The MRIs of 96 patients who were over 60 years old (M:F = 50:46; mean age 68.4 years; range 61-86 years) were independently analyzed by seven radiologists. Interobserver and intraobserver agreements were analyzed using the percentage agreement, kappa statistics, and intraclass correlation coefficient (ICC). RESULTS: For the distinction among the three individual grades at all six neural foramina, the ICC ranged from 0.68 to 0.73, indicating fair to good reproducibility. The percentage agreement ranged from 60.2% to 70.6%, and the kappa values (κ = 0.50-0.58) indicated fair to moderate agreement. The percentages of intraobserver agreement ranged from 85.4% to 93.8% (κ = 0.80-0.92), indicating near perfect agreement. CONCLUSION: The new MRI grading system shows sufficient interobserver and intraobserver agreement to reliably assess cervical NFS.
Aged ; Aged, 80 and over ; Female ; Humans ; *Magnetic Resonance Imaging ; Male ; Middle Aged ; Reproducibility of Results ; Severity of Illness Index ; Spinal Stenosis/pathology/*radiography

OBJECTIVE: To evaluate spine magnetic resonance imaging (MRI) inter-reader and intra-reader reliabilities using the thoracolumbar injury classification system and severity score (TLICS) and to analyze the effects of reader experience on reliability and the possible reasons for discordant interpretations. MATERIALS AND METHODS: Six radiologists (two senior, two junior radiologists, and two residents) independently scored 100 MRI examinations of thoracolumbar spine injuries to assess injury morphology and posterior ligamentous complex (PLC) integrity according to the TLICS. Inter-reader and intra-reader agreements were determined and analyzed according to the number of years of radiologist experience. RESULTS: Inter-reader agreement between the six readers was moderate (k = 0.538 for the first and 0.537 for the second review) for injury morphology and fair to moderate (k = 0.440 for the first and 0.389 for the second review) for PLC integrity. No significant difference in inter-reader agreement was observed according to the number of years of radiologist experience. Intra-reader agreements showed a wide range (k = 0.538-0.822 for injury morphology and 0.423-0.616 for PLC integrity). Agreement was achieved in 44 for the first and 45 for the second review about injury morphology, as well as in 41 for the first and 38 for the second review of PLC integrity. A positive correlation was detected between injury morphology score and PLC integrity. CONCLUSION: The reliability of MRI for assessing thoracolumbar spinal injuries according to the TLICS was moderate for injury morphology and fair to moderate for PLC integrity, which may not be influenced by radiologist' experience.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Child ; Female ; Humans ; *Injury Severity Score ; Ligamentum Flavum/pathology ; Lumbar Vertebrae/*injuries/pathology ; Magnetic Resonance Imaging/*methods ; Male ; Middle Aged ; Observer Variation ; Reproducibility of Results ; Retrospective Studies ; Spinal Injuries/*classification/*pathology ; Thoracic Vertebrae/*injuries/pathology ; Thoracic Wall/pathology ; Young Adult