Purpose: The opacity of zirconia sometimes requires a veneering material; thus lithium disilicate, a veneer material with excellent strength, can be used. This study investigated the fracture resistance of zirconia–lithium disilicate (Zr-LS2) bi-layered crowns according to the design of the substructure. Materials and Methods: Five groups of posterior Zr-LS2 restorations (Zirtooth and Amber LiSi-POZ) were fabricated with different zirconia substructure coverage (control group, groups half occlusal zirconia coverage; 1/2OZ, and three-quarter occlusal zirconia coverage; 3/4OZ) and margin designs (control group, groups collar margin; C-M, and collarless margin; Cl-M). All restorations were cemented with self-adhesive resin cement followed by 24-h water storage and thermocycling (10,000 cycles, 5°C and 55°C). The fracture load was measured, and failure mode analysis, fractography, and elemental analysis were performed. The one-way analysis of variance and Fisher’s exact test were performed for statistical analyses (α=.05). Results: A significant difference was found in the fracture load of Zr-LS2 restorations according to the zirconia coverage of the occlusal area and margin design (P<.05). Group 3/4OZ was significantly larger than the control group C and 1/2OZ (P<.05). The C-M group had greater fracture loads based on margin design than the control group C and Cl-M (P<.05). Conclusion The fracture resistance of posterior Zr-LS2 restorations increased with the zirconia coverage, occlusal thickness, and collar margin.

The fundamental principles for treating ankle fractures, as with other intra-articular fractures, are anatomical reduction and stable internal fixation. Despite successful reduction, between 14% and 40% of patients continue to experience persistent pain or unsatisfactory functional outcomes. Furthermore, approximately 1% of patients progress to post-traumatic arthritis, necessitating further surgical intervention. Ankle fractures are frequently accompanied by intra-articular injuries, including osteochondral lesions, ligament tears, and syndesmosis injuries. Arthroscopy is becoming increasingly prevalent in managing acute ankle fractures by assessing intra-articular damage and facilitating accurate reduction. This review examined the role and indications for arthroscopy in ankle fractures, particularly emphasizing its benefits in diagnosing and managing associated injuries, including osteochondral lesions, syndesmosis, and deltoid ligament injuries. Furthermore, arthroscopy facilitates fracture reduction, offering a minimally invasive approach with a shorter recovery period and enhanced visualization. Its use extends to pediatric fractures and complex cases such as Maisonneuve and calcaneal fractures, potentially improving outcomes while minimizing complications. Understanding the evolving indications and benefits of arthroscopy for ankle fractures can lead to improved clinical outcomes and reduced complications.

Background: The diagnosis of tuberculous pleural effusion (TPE) often relies on pleural fluid adenosine deaminase (ADA) levels. The diagnostic utility of ADA, however, is influenced by the prevalence of tuberculosis (TB) in local populations. Malignant pleural effusion (MPE) cases can exhibit moderately elevated ADA levels comparable to those seen in TPE. As population aging potentially impacts ADA levels, global TB incidence is decreasing whereas the burden of malignancy is on the rise. Consequently, epidemiological shifts and temporal changes in ADA distribution complicate the differential diagnosis between TPE and MPE when ADA levels are within the 40–70 IU/L range. Nonetheless, data specific to this subset are scarce. Methods: This retrospective study included consecutive patients aged > 18 years with confirmed TPE and MPE, spanning from 2012 to 2023. ADA levels in pleural fluid were categorized into three groups: < 40 IU/L, 40–70 IU/L, and > 70 IU/L. The study examined annual trends in the frequency of new cases and ADA level distributions over time and identified discriminating factors between TPE and MPE in cases with ADA levels of 40–70 IU/L. Results: In total, 297 TPE and 369 MPE cases were included in this study. Over the study period, the frequency of TPE progressively declined, while that of MPE increased. In the most recent four-year period, new TPE and MPE cases with ADA levels of 40–70 IU/L occurred at comparable numbers. Multivariable analysis identified pleural fluid carcinoembryonic antigen (CEA) levels and the number of focal pleural nodules as independent predictors for MPE. Specifically, the presence of either CEA levels > 15.7 ng/mL or more than eight pleural nodules yielded the highest diagnostic accuracy with a sensitivity of 88%, specificity of 100%, and an area under the curve of 0.95. Conclusion The differential diagnosis between TPE and MPE with pleural ADA levels of 40–70 IU/L has become increasingly critical due to evolving epidemiological patterns and ADA distribution changes over time. Pleural fluid CEA levels and the characteristics of pleural nodules may offer valuable guidance in distinguishing between TPE and MPE within this diagnostic gray zone.

Background: To investigate the clinicopathologic pattern of prostate cancer (PCa) in elderly patients compared with their younger counterparts with a prostate-specific antigen (PSA) level below the low-risk threshold (< 10 ng/mL), which is often a deciding factor for biopsy. Methods: A nationwide database of PCa at the time of biopsy from 2010 to 2020 was constructed from 39 hospitals. Patients were categorized into age groups of < 64 years, 65–69 years, 70–74 years, and ≥ 75 years considering guidelines that recommend PSA testing only for those aged 55–69 years during the study period, the average age of Korean PCa registrants of 70.3 years (2010–2020), and the average life expectancy of Korean males of 80.3 years (2020). Results: The mean ± standard deviation age was 70.3 ± 8.2 years, which was normally distributed (kurtosis = 0.095). Among 14,548 subjects, 54.1%, 39.5%, and 6.4% of them had high-risk disease, intermediate-risk disease, and low-risk disease, respectively. Based on three risk parameters, a marked increase in high-risk cancer was observed in the oldest age group (linear combination, P < 0.001). The same pattern was observed among patients with low-risk disease (PSA < 10 ng/mL), who were divided into PSA tiers as follows: 4–5 ng/mL (P < 0.001), 5–6 ng/mL (P < 0.001), 6–7 ng/mL (P < 0.001), 7–8 ng/mL (P < 0.001), 8–9 ng/mL (P = 0.009), and 9–10 ng/mL (P < 0.001). In all PSA tiers between 4 and 10 ng/mL, multivariate analysis demonstrated a significantly higher prevalence of high-risk cancer in the oldest age group than in the youngest age group. In the lowest tier (4–5 ng/mL), 35.2% of those aged over 75 years had high-risk PCa. Conclusion The older the patient, the more aggressive the PCa. Moreover, there was an increase in high-risk PCa in older males compared with younger males even with a PSA level below the low-risk threshold of 10 ng/mL, suggesting the need to strengthen cancer screening policies in the older population.

Background: With growing elderly populations, management of patients with acute stroke is increasingly important. In South Korea, the Acute Stroke Quality Assessment Program (ASQAP) has contributed to improving the quality of stroke care and practice behavior in healthcare institutions. While the mortality of hemorrhagic stroke remains high, there are only a few assessment indices associated with hemorrhagic stroke. Considering the need to develop assessment indices to improve the actual quality of care in the field of acute stroke treatment, this study aims to investigate the current status of human resources and practices related to the treatment of patients with acute stroke through a nationwide survey. Methods: For the healthcare institutions included in the Ninth ASQAP of the Health Insurance Review and Assessment Service (HIRA), data from January 2022 to December 2022 were collected through a survey on the current status and practice of healthcare providers related to the treatment of patients with acute stroke. The questionnaire consisted of 19 items, including six items on healthcare providers involved in stroke care and 10 items on the care of patients with acute stroke. Results: In the treatment of patients with hemorrhagic stroke among patients with acute stroke, neurosurgeons were the most common providers. The contribution of neurosurgeons in the treatment of ischemic stroke has also been found to be equivalent to that of neurologists. However, a number of institutions were found to be devoid of healthcare providers who perform definitive treatments, such as intra-arterial thrombectomy for patients with ischemic stroke or cerebral aneurysm clipping for subarachnoid hemorrhage. The intensity of the workload of healthcare providers involved in the care of patients with acute stroke, especially those involved in definitive treatment, was also found to be quite high. Conclusion Currently, there are almost no assessment indices specific to hemorrhagic stroke in the ASQAP for acute stroke. Furthermore, it does not reflect the reality of the healthcare providers and practices that provide definitive treatment for acute stroke. The findings of this study suggest the need for the development of appropriate assessment indices that reflect the realities of acute stroke care.

Background: The accuracy of Logical Observation Identifiers Names and Codes (LOINC) mappings is reportedly low, and the LOINC codes used for research purposes in Korea have not been validated for accuracy or usability. Our study aimed to evaluate the discrepancies and similarities in interoperability using existing LOINC mappings in actual patient care settings. Methods: We collected data on local test codes and their corresponding LOINC mappings from seven university hospitals. Our analysis focused on laboratory tests that are frequently requested, excluding clinical microbiology and molecular tests. Codes from nationwide proficiency tests served as intermediary benchmarks for comparison. A research team, comprising clinical pathologists and terminology experts, utilized the LOINC manual to reach a consensus on determining the most suitable LOINC codes. Results: A total of 235 LOINC codes were designated as optimal codes for 162 frequent tests.Among these, 51 test items, including 34 urine tests, required multiple optimal LOINC codes, primarily due to unnoted properties such as whether the test was quantitative or qualitative, or differences in measurement units. We analyzed 962 LOINC codes linked to 162 tests across seven institutions, discovering that 792 (82.3%) of these codes were consistent. Inconsistencies were most common in the analyte component (38 inconsistencies, 33.3%), followed by the method (33 inconsistencies, 28.9%), and properties (13 inconsistencies, 11.4%). Conclusion This study reveals a significant inconsistency rate of over 15% in LOINC mappings utilized for research purposes in university hospitals, underlining the necessity for expert verification to enhance interoperability in real patient care.

Background: Identifying factors associated with early post-discharge outpatient care is crucial to prevent relapse and suicide in patients with schizophrenia. This study aimed to investigate factors associated with receiving follow-up care within seven days after hospital discharge among patients with schizophrenia. Methods: This nationwide population-based study was conducted using data from the National Health Insurance Claim Database of South Korea. All patients aged ≥ 18 years, newly admitted to the hospital with schizophrenia between January 1, 2017, and December 31, 2018, were included. The outcome of interest was the receipt of outpatient follow-up care within seven days of hospital discharge. Patients’ general characteristics and healthcare services were included as independent variables. A generalized estimating equation model was used to examine factors associated with the outcome. Results: Of 17,565 patients with schizophrenia, 37.6% received outpatient follow-up care within seven days after hospital discharge. Patients who were older and male were less likely to receive follow-up care seven days after discharge. Patients with prior psychiatric outpatient care to their index admission were more likely to receive follow-up care than those without prior outpatient care. A longer hospital stay significantly decreased the likelihood of receiving outpatient follow-up. However, comorbid alcohol use disorder was not associated with receiving follow-up care within seven days of discharge. Conclusion This study highlights the need to ensure continuity of care for patients with schizophrenia during discharge planning, with particular attention to vulnerable patients.

The applicability of the Phoenix criteria and Phoenix Sepsis Score in higher-resource pediatric intensive care units (PICUs) outside the United States requires further validation. A retrospective cohort study analyzed electronic health records of 1,304 PICU admissions under 18 years old with suspected infection between February 2017 and December 2023. The score was calculated using two methods: 24-hour assessment, based on worst sub-scores within 24 hours of admission, and prompt assessment, using values closest to admission within 6 hours before or after. Based on the 24-hour assessment, in-hospital mortality was 8.3% for sepsis and 10.3% for septic shock. The score demonstrated an area under the precision-recall curve of 0.42 (95% confidence interval, 0.31–0.55) for in-hospital mortality. Results were consistent across both assessment methods. The Phoenix criteria and the Phoenix Sepsis Score are reliable predictors of mortality outcomes. Further investigation in diverse clinical settings is warranted.

Background: The heart donor allocation system in South Korea is divided into three regions, with priority given to recipients within the same region over those in other regions of the same tier. It is commonly believed that heart transplantation (HT) within the same region can reduce ischemic time (IT), although its clinical impact remains unclear. The purpose of this study is to compare the characteristics and outcomes of intra-region HT and inter-region HT. Methods: From 2014 to 2022, a total of 115 adult patients underwent isolated HT at a tertiary hospital. Of these, 58 recipients (54.5 ± 10.3 years, female, 36.2%) underwent intra-region HT and 57 recipients (53.9 ± 14.1 years, female, 31.6%) underwent inter-region HT. Extracorporeal membrane oxygenation-bridged HTs accounted for 50.0% and 54.4% of cases, respectively (P = 0.638). There were no differences in preoperative characteristics between the two groups. Results: The median inter-hospital distance (38.0 [32.0–112.0] km vs. 351.0 [300.0–390.5] km, P < 0.001) and total IT (153 [123–170] minute vs. 265 [243–298] minute, P < 0.001) were longer in the inter-region group than intra-region group. Despite these differences, both groups showed similar clinical outcomes. The 30-day mortality rates were 5.2% and 5.3% (P < 0.99), respectively. There were no differences in postoperative cardiac index, early adverse outcomes, or long-term survival between the two groups. The inter-hospital distance and cold IT showed a strong positive correlation (time [minute] = 39.462 + 0.410 × distance [km]). Conclusion Despite the difference in IT, there was no difference in postoperative outcomes between the two groups. Based on these findings, the effect of donor location on the outcomes of HT in South Korea is not considered significant.

Background: Psychological test reports are essential in assessing intellectual functioning, aiding in diagnosing and treating intellectual disability (ID) and attention-deficit/ hyperactivity disorder (ADHD). However, these reports can have several problems because they are diverse, unstructured, subjective, and involve human errors. Additionally, physicians often do not read the entire report, and the number of reports is lower than that of diagnoses. Methods: We developed explainable predictive models for classifying IDs and ADHDs based on written reports to address these issues. The reports of 1,475 patients with IDs and ADHDs who underwent intelligence tests were used for the models. These models were developed by analyzing reports using natural language processing (NLP) and incorporating the physician’s diagnosis for each report. We selected n-gram features from the models’ results by extracting important features using SHapley Additive exPlanations and permutation importance to make the models explainable. Developing the n-gram feature-based original text search system compensated for the lack of human readability caused by NLP and enabled the reconstruction of human-readable texts from the selected n-gram features. Results: The maximum model accuracy was 0.92, and the 80 human-readable texts were restored from four models. Conclusion The results showed that the models could accurately classify IDs and ADHDs, even with a few reports. The models were also able to explain their predictions. The explainability-enhanced model can help physicians understand the classification process of IDs and ADHDs and provide evidence-based insights.