Background: s/Aims: Phase angle (PhA), as measured by bioelectrical impedance analysis, provides insights into hydration and nutritional status, making it a prognostic indicator of frailty. While low preoperative PhA has been linked to postoperative complications in cancer patients, its predictive value in individuals undergoing pancreaticoduodenectomy (PD) has not been thoroughly investigated.This study aims to evaluate the clinical utility of preoperative PhA in predicting postoperative complications for patients undergoing PD. Methods: Among 41 patients who underwent PD at Seoul National University Hospital between September and December 2024, 35 were included in the analysis after excluding 6 patients who had concomitant blood vessel or other organ resections. Patients were divided into low (Comprehensive Complication Index [CCI] ≤ 20) and high (CCI > 20) complication groups based on the CCI, derived from the Clavien–Dindo classification. The differences in PhA between the two groups were analyzed, and logistic regression was performed to assess the relationship between PhA and CCI. Results: The mean PhA was significantly lower in the high-CCI group compared to the low-CCI group (5.7° vs. 6.7°, p = 0.025). Multivariate logistic regression analysis indicated that PhA (odds ratio: 0.17; 95% confidence interval: 0.04–0.68; p = 0.012) was an independent predictor of high CCI. A low preoperative PhA was associated with an increased risk of postoperative complications following PD. Conclusions Preoperative PhA may serve as a valuable predictive indicator of postoperative complications after PD, enabling the identification of patients who could benefit from preoperative prehabilitation, including nutritional support.

Objective: To investigate and compare proprioception characteristics in healthy adults using different measurement methods. Methods: Participants engaged in three tasks using a device developed to assess elbow joint proprioception: the ipsilateral matching task (IMT), contralateral matching task (CMT), and pointing task (PT). Each task was performed three times at different angles (30°, 50°, and 70°) in a randomised order for nine trials and tested for both the right and left arms. Activity level was measured using the International Physical Activity Questionnaire-Short Form. Results: Twenty healthy adults (10 males, mean age: 39.80±12.19 years) were enrolled. The absolute error of the IMT was significantly lower than that of the CMT and PT (Bonferroni [Bonf.] p=0.029 and 0.016, respectively). PT showed a higher variable error than that of IMT and CMT (Bonf. p<0.001, and 0.040, respectively). There were no significant differences in errors across tasks based on sex or age. The total International Physical Activity Questionnaire- Short Form score showed statistically significant correlations with the absolute error (r=-.460, p=0.041) and constant error (r=-.469, p=0.037) of the CMT and variable error of the PT (r=-.478, p=0.033). Conclusion This study demonstrated that different proprioceptive tasks can assess the unique characteristics of proprioceptive function. The IMT produced lower error values than those of the CMT and PT, with the PT exhibiting higher variability. These differences may stem from distinct mechanisms that depend on the nature of each task and warrant further investigation.

Purpose: Endoscopic submucosal dissection (ESD) has become a standard minimally invasive treatment for selected patients with early gastric cancer (EGC). This study presents the first nationwide survey of patients with EGC treated with ESD in 2023, conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research. Materials and Methods: Data were retrospectively collected from participating referral centers across Korea using a standardized case report form covering patient characteristics, tumor features, procedural details, histopathological findings, and clinical outcomes.Descriptive and comparative analyses were conducted to summarize nationwide ESD practice patterns and outcomes. Results: Data from 5,460 ESD cases from 5,250 patients across 27 institutions were analyzed. The mean age was 67.4 years, with 74.1% males. Multiple synchronous lesions were identified in 3.7%. Most lesions were located in the lower third of the stomach (64.0%), and differentiated-type adenocarcinomas accounted for 87.8%. The en bloc and complete resection rates were 99.2% and 91.4%, respectively. Curative resection was achieved in 80.5%, whereas local non-curative resection (L-NCR) and surgical non-curative resection (S-NCR) were identified in 2.8% and 16.7%, respectively. Additional surgery was performed more frequently in patients with S-NCR than in those with L-NCR (59.3% vs. 24.7%). The bleeding and perforation rates were 3.6% and 0.9%, respectively, and were mostly managed conservatively or endoscopically. The median length of hospitalization was 4.0 days. Conclusions This first nationwide survey provides a comprehensive overview of the current practice of EGC treatment using ESD in Korea, demonstrating high technical success and safety, and establishing a baseline dataset for future longitudinal research.

Purpose: This study evaluated long-term trends in gastric cancer epidemiology and survival with a focus on conditional relative survival (CRS). Materials and Methods: Using the Korea Central Cancer Registry, we analyzed 665,184 patients who were newly diagnosed with gastric cancer between 1999 and 2022.The study period was divided into four intervals: Period I (1999–2005), Period II (2006–2011), Period III (2012–2017), and Period IV (2018–2022). Temporal trends in the incidence and mortality were assessed using crude and age-standardized rates. Relative survival was estimated using the Ederer II method, and the 5-year CRS was calculated according to the survival duration after diagnosis. Results: The incidence of gastric cancer increased until 2011 and subsequently declined, with a marked decrease observed in 2020. Individuals aged ≥70 years consistently had the highest incidence rates. Mortality rates showed a sustained decline throughout the study period. The overall 5-year relative survival improved from 69.8% in Period II to 78.4% in Period IV. The 5-year CRS increased from 86.1% at 1 year after diagnosis to 96.3% at 5 years.Patients with localized stage maintained a 5-year CRS above 95% at 1 year after diagnosis, whereas those with regional and distant stages showed 5-year CRS that consistently remained below 95%. Conclusions The incidence and mortality rates of gastric cancer in Korea have declined over the past two decades, accompanied by improved survival outcomes. The CRS analysis suggests that long-term follow-up is warranted, with the optimal duration varying according to patient characteristics.

Background/Aims: The International Anorectal Physiology Working Group (IAPWG) has proposed a standardized protocol and the London classification to enhance the consistency and diagnostic accuracy of anorectal manometry (ARM). However, real-world adoption in Asian countries has not been systematically assessed. This study aims to evaluate current ARM practices and adherence to the IAPWG protocol across Asian centers. Methods: A cross-sectional, 50-item web-based survey was distributed to gastroenterologists and motility specialists practicing in Asian countries. Results: Thirty-one centers from 8 countries responded (20 in Korea, 3 in Japan, 2 in Taiwan, 1 in China, and 7 in other countries). High-resolution ARM was used in 80.6% of centers, primarily with solid-state catheters. While all centers performed rest and short squeeze maneuvers, only 58.1% conducted all maneuvers recommended by the IAPWG protocol.Considerable variation was observed in test methodology and interpretation, including definitions of resting pressure, squeeze duration, push maneuver repetition, and rectal balloon volume for rectoanal inhibitory reflex. For balloon expulsion and rectal sensory testing, centers differed in patient positioning, balloon type, inflation methods, and threshold definitions. Only 38.7% of centers reported having institutional normative values for test interpretation, and 64.5% applied the London classification. Conclusions Across Asian centers, ARM practice shows marked regional variation and incomplete implementation of the IAPWG standardized protocol and London classification, highlighting persistent gaps in standardization. Strengthening procedural guidance, regionally appropriate normative data, and interpretation criteria through coordinated education and international collaboration is needed to support more consistent and clinically meaningful use of ARM in routine practice.

New psychoactive substances (NPS) have rapidly emerged in illicit drug markets worldwide and are increasingly encountered in postmortem examinations. However, postmortem data on NPS-related deaths remain limited worldwide. This study describes postmortem findings from forensic autopsy cases in which NPS were detected and explores the characteristics of these deaths through a retrospective review. Six postmortem cases were identified between 2023 and 2024. The cases predominantly involved young adults. Toxicological analysis identified synthetic cannabinoids, dissociatives, and a stimulant, either alone or in combination with alcohol or conventional illicit drugs such as methamphetamine and 3,4-methylenedioxymethamphetamine (MDMA). Drug paraphernalia or a documented history of drug use was identified in only some cases. The causes of death included acute intoxication and traumatic deaths in which drug intoxication may have contributed to abnormal behavior and fatal outcomes. These findings provide preliminary forensic evidence of the emergence of NPS in South Korea. They underscore the importance of postmortem examination with comprehensive toxicological screening and continued surveillance of emerging psychoactive substances in forensic practice. They also suggest the value of reviewing a history of prior substance use even in unexpected sudden deaths not initially suspected to be drugrelated.

Myopia, particularly high myopia, is a significant risk factor for several ocular pathologies including cataract, glaucoma, and retinal detachment. Excessive axial elongation associated with high myopia can induce biomechanical stretching, increasing the risk of serious complications like posterior staphyloma and myopic maculopathy. Global meta-analyses estimate that approximately 10 million people were visually impaired due to myopic maculopathy in 2015, with 3 million being blind. Recent nationwide surveys in South Korea revealed a prevalence of 65.4% for myopia and 6.9% for high myopia in children and adolescents, highlighting the urgent need for effective management. Delaying the onset and slowing the progression of myopia during childhood and adolescence is crucial for reducing the potential lifetime risk of these complications. This consensus statement, prepared by the Korean Myopia Society for the Korean Association for Pediatric Ophthalmology and Strabismus (KAPOS), reviews the current evidence for myopia control interventions and provides management strategies applicable to the South Korean clinical setting. Key interventions covered include lifestyle modifications (outdoor time, near work adjustment), optical methods (myopia-control spectacle lenses, dual-focus soft contact lenses, orthokeratology), and pharmacologic treatment (low-concentration atropine), as well as combination therapies. The statement also addresses patient selection, treatment outcome evaluation using spherical equivalent and axial length changes, and the crucial aspects related to treatment cessation and the rebound effect.

Purpose: Postoperative endophthalmitis is a sight-threatening intraocular infection requiring prompt treatment. This study aimed to compare the clinical outcomes of intravitreal 0.625% povidone-iodine (PI) injection with intravitreal antibiotic injection for the treatment of postoperative endophthalmitis. Methods: A retrospective review of 40 eyes diagnosed with postoperative endophthalmitis was conducted. Patients were divided into two groups: group 1 received intravitreal 0.625% PI injection (0.1 mL), while group 2 received intravitreal antibiotic injection. Clinical data, including best-corrected visual acuity (BCVA), intraocular pressure, the number of intravitreal injections, duration of anterior chamber hypopyon, and the need for pars plana vitrectomy (PPV), were analyzed. Results: Group 1 (24 eyes) showed significant improvements in BCVA posttreatment (mean, 1.04 ± 0.95 logMAR; p < 0.001) compared to group 2 (16 eyes; mean, 1.26 ± 0.99 logMAR; p = 0.092). Severe visual impairment (BCVA < 10 / 100) was significantly less frequent in group 1 (25.0%) than in group 2 (62.5%) (p = 0.025). The mean duration of hypopyon was shorter in group 1 (2.6 ± 2.2 days) compared to group 2 (6.4 ± 7.3 days, p = 0.048). Fewer intravitreal injections (p = 0.002) and PPV (p = 0.002) were required in group 1. Conclusions Intravitreal 0.625% PI injection was associated with fewer intravitreal injections, shorter hypopyon duration, and more favorable visual outcome–related measures, including significant visual improvement from baseline and a lower frequency of severe visual impairment, compared with intravitreal antibiotic treatment. These findings suggest that PI may be considered a safe and effective initial treatment option for postoperative endophthalmitis. Further prospective studies are needed to validate these results.

Recent advancements in artificial intelligence have led to increased interest in predictive modeling across various domains, including medicine. Although numerous metrics have been established for binary classification, the growing adoption of multi-class systems necessitates robust evaluation measures. However, comprehensive simulation studies comparing the performance of existing multi-class metrics under diverse data conditions remain limited. In this study, we first provide a concise overview of commonly used accuracy metrics for multi-class classification. Then, we report a simulation study that systematically evaluates several diagnostic accuracy measures under a wide range of scenarios, including three- and five-class settings, balanced and imbalanced sample sizes, and different distributional assumptions for predictors. We assessed each metric’s performance in terms of bias and 95% confidence interval coverage. Under balanced conditions, most metrics demonstrated stable and unbiased performance, closely approximating the true values. However, under imbalanced conditions, greater bias was observed, with the M-index and polytomous discrimination index exhibiting comparatively more stable performance across various scenarios. The micro-averaged receiver operating characteristic curve area consistently showed higher bias under class imbalance. Finally, we applied these metrics to a glioma tumor grading task using external datasets. This study provides a systematic comparison of commonly used metrics and offers practical guidance for selecting appropriate measures in multi-class classification tasks.