1.Intraoperative Visual Evoked Potential Monitoring in Endoscopic Endonasal Surgery for Nonpituitary Adenoma Suprasellar Tumors
Young Nam KWON ; Hwa Reung LEE ; Myung Jae LEE ; Young Ung KIM ; Seung Woo KIM ; Ha Young SHIN ; Sung-Min KIM ; Ju Hyung MOON ; Jong Hee CHANG ; Eui Hyun KIM
Journal of Clinical Neurology 2026;22(2):221-228
Background:
and Purpose Intraoperative visual evoked potential (VEP) monitoring has been studied mainly in pituitary adenoma, while its role in nonpituitary suprasellar tumors has remained unclear. This study evaluated the predictive usefulness of intraoperative VEP monitoring during endoscopic endonasal surgery (EES) and aimed to identify optimal alarm criteria for visual outcomes.
Methods:
We retrospectively analyzed a cohort of 87 patients who underwent EES with intraoperative VEP monitoring between April 2021 and September 2023. Visual outcomes were evaluated preoperatively and at short-term (≤3 months) and long-term (12 months) followups, with visual deterioration at these time points defined as worsening of either visual acuity or the visual field. Reductions in the VEP amplitude were quantified using both the maximum intraoperative decrease and the final amplitude after recovery. Receiver operating characteristic (ROC) curve analyses were performed to identify the optimal alarm thresholds, and the sensitivity, specificity, positive predictive value, and negative predictive value were calculated for short-term and long-term visual deteriorations.
Results:
Short-term and long-term visual deteriorations were detected in 12 (9.2%) and 5 (3.8%) of the 130 analyzed eyes, respectively. ROC curve analyses identified ≥40% and ≥30% reductions in the N75–P100 amplitude as optimal alarm criteria for short-term and long-term visual deteriorations, respectively. A 30% reduction without intraoperative recovery demonstrated markedly higher sensitivity than the conventional 50% alarm threshold for short-term (58.3% vs. 33.3%) and long-term (80.0% vs. 20.0%) outcomes, while maintaining acceptable specificity (82.2% and 80.8%, respectively).
Conclusions
A 30% reduction in amplitude represents a more-sensitive and clinically relevant alarm threshold than a 50% reduction for intraoperative VEP monitoring during EES for nonpituitary suprasellar tumors. Incorporating both the magnitude and recovery pattern of VEP amplitude changes may improve the accuracy of predictions of long-term visual deterioration. However, the potential for false positives warrants cautious interpretation, and further studies are needed to validate the impact of intraoperative VEP monitoring on visual outcomes.
2.Muscle Loss Driven by Extracellular Signal-Regulated Kinase Suppression via β-Adrenergic Activation in High-Normal Catecholamine Status
Jieun LEE ; Ju Yeon KWAK ; Ho Yeop LEE ; Ji Sun MOON ; Hyo Ju JANG ; Ha Thi NGA ; Thi Linh NGUYEN ; Alfin Mohammad ABDILLAH ; Junglyun KIM ; Sihwan KIM ; Yong Ryoul YANG ; Jeong Eun LEE ; Hyon-Seung YI
Endocrinology and Metabolism 2026;41(2):319-332
Background:
Catecholamines play a crucial role in muscle biogenesis, but their persistent elevation is linked to muscle wasting, which is poorly understood. This study aimed to investigate the association between catecholamine levels and age-related muscle loss.
Methods:
This retrospective study evaluated the plasma levels of two catecholamines, metanephrine and normetanephrine, and the clinical characteristics of 830 patients with adrenal incidentaloma on computed tomography (CT). Cross-sectional CT data at the L3 lumbar vertebrae were used to measure muscle areas. In vitro studies on C2C12 myotubes were conducted to examine β-adrenergic receptor signaling pathways and their role in myogenesis.
Results:
Men had significantly higher mean metanephrine levels of 0.17 nmol/L and normetanephrine levels of 0.63 nmol/L than women (P<0.05). Total abdominal muscle area was negatively correlated with catecholamine levels in both men and women, with the strongest negative correlation between normetanephrine levels and total abdominal muscle area in men (r=–0.31, P<0.001). Similarly, the strongest negative correlation between visceral fat area and metanephrine was observed in men (r=–0.25, P=0.004). Clenbuterol, a β-adrenergic receptor agonist, inhibited myogenesis, including myotube formation by extracellular signal-regulated kinase (ERK) suppression in C2C12 myoblasts. Conversely, β-blockers increased myogenesis via increasing ERK phosphorylation in C2C12 cells. These findings suggest that β-adrenergic modulation influences skeletal muscle differentiation, with ERK phosphorylation.
Conclusion
Catecholamine levels are associated with age, sex, muscle mass, and fat mass. Monitoring catecholamine levels, particularly in older men and in individuals with reduced muscle mass, may help manage age-related muscle loss and lead to individualized treatment strategies.
3.Interventricular septal hematoma following left bundle branch area pacing: a rare case with atypical arrhythmic presentation
Seongjin PARK ; Juwon KIM ; Seung-Jung PARK ; Kyoung-Min PARK ; Young Keun ON ; Ju Youn KIM
International Journal of Arrhythmia 2026;27(1):e7-
Background:
Left bundle branch area pacing (LBBAP) provides physiologic ventricular activation but requires deep lead penetration into the interventricular septum, which can rarely cause various complications.Case presentation: A 57-year-old woman with high-degree atrioventricular block underwent dual-chamber pacemaker implantation with stylet-driven LBBAP via the left axillary vein. Within hours, she developed nausea, vomiting, and frequent ventricular premature contractions with non-sustained ventricular tachycardia, while remaining hemodynamically stable. Transthoracic echocardiography revealed a well-circumscribed echo lucent mass in the mid interventricular septum (15.6 × 24.7 mm) consistent with hematoma, without pericardial effusion or left ventricular outflow tract obstruction. In the absence of clinical deterioration, a conservative strategy with close rhythm monitoring and serial echocardiography was chosen. The hematoma regressed progressively with near-complete resolution at two weeks, and the patient remained asymptomatic with stable lead function at 6-month follow-up.
Conclusions
Interventricular septal hematoma is a rare complication of LBBAP that may present predominantly with ventricular arrhythmia. In hemodynamically stable patients without mechanical compromise, careful surveillance can allow successful conservative management without surgical intervention.
4.Acute Heart Failure Across the Ejection Fraction Spectrum: Phenotypes, Management, and Outcomes From Nationwide KorHF III Registry
Huijin LEE ; Eung Ju KIM ; Seong Woo HAN ; Seong-Mi PARK ; Hyung-Seop KIM ; Myung-Chan CHO ; Hyo-Suk AHN ; Mi-Seung SHIN ; Seok-Jae HWANG ; Jin-Ok JEONG ; Dong Heon YANG ; Junho HYUN ; Jin Oh CHOI ; Hae-Young LEE ; Byung-Su YOO ; Seok-Min KANG ; Dong-Ju CHOI ; Hyun-Jai CHO ;
International Journal of Heart Failure 2026;8(1):43-55
Background and Objectives:
Clinical characteristics and outcomes in acute heart failure (AHF) vary by phenotype. We assessed phenotype-specific features, treatment patterns, and outcomes in a nationwide Korean cohort.
Methods:
The Korean Heart Failure III registry prospectively enrolled 7,351 AHF admissions at 47 hospitals. Among 6,777 patients with available left ventricular ejection fraction (EF), phenotypes were defined as heart failure with reduced EF (HFrEF, ≤40%), mildly reduced EF (HFmrEF,41–49%), or preserved EF (HFpEF, ≥50%). The primary endpoint was a 12-month composite of all-cause death or heart transplantation, evaluated from index admission and, among hospital survivors, from discharge. We used inverse probability weighting (multinomial generalized boosted models with stabilized, trimmed weights) and weighted Cox proportional-hazards models to estimate hazard ratios (HRs).
Results:
Phenotype distribution was 58.9% HFrEF, 13.6% HFmrEF, and 27.5% HFpEF. Crude 12-month composite rates from index admission were 13.4% (HFrEF), 12.7% (HFmrEF), and 16.8% (HFpEF). After weighting, from index admission, HFmrEF (HR, 0.892; 95% confidence interval [CI], 0.731–1.088) and HFpEF (HR, 1.101; 95% CI, 0.939–1.291) did not differ from HFrEF; from discharge, HFpEF had modestly higher risk (HR, 1.207; 95% CI, 1.008–1.445) whereas HFmrEF did not (HR, 1.039; 95% CI, 0.844–1.279). Hyponatremia and chronic kidney disease were consistent adverse markers, while angiotensin-converting enzyme inhibitor/ angiotensin II receptor blocker use at discharge was protective.
Conclusions
Across the EF spectrum, phenotypes showed distinct profiles and risk. Postdischarge risk was modestly higher in HFpEF, supporting phenotype-tailored care and systematic discharge optimization in Korean patients with AHF.
5.Management of Abrupt Vessel Closure During Percutaneous Coronary Intervention: A Narrative Review
Yongwhan LIM ; Seok OH ; Joon Ho AHN ; Seung Hun LEE ; Dae Young HYUN ; Kyung Hoon CHO ; Min Chul KIM ; Doo Sun SIM ; Young Joon HONG ; Ju Han KIM ; Youngkeun AHN
Journal of Cardiovascular Intervention 2026;5(1):1-10
Abrupt vessel closure (AVC) is a complication of percutaneous coronary intervention (PCI) and is defined as the sudden cessation of forward coronary blood flow due to a variety of mechanisms. The incidence of AVC has markedly decreased from approximately 3.0% in the early era to about 0.3% today. Nevertheless, cardiovascular interventionists must remain prepared to manage AVC effectively, given its significant impact on clinical outcomes.AVC can arise from several mechanisms, including dissection, intramural hematoma, intracoronary thrombosis, air embolism, vasospasm, and no-reflow. The clinical impact of AVC varies depending on the extent of myocardium affected, ranging from asymptomatic events or transient ischemic chest pain to cardiogenic shock or cardiac arrest. Both a general approach for stabilizing hemodynamic consequences and an etiology-specific management strategy are essential. Hasty decision-making may worsen the situation, whereas a structured approach—focused on hemodynamic stabilization, logical diagnostic processes, and targeted interventions—can improve outcomes. In this narrative review, we describe the mechanisms underlying each etiology, outline mechanism-specific management strategies, and discuss general approaches to managing patients with AVC through logical diagnostic and treatment processes. We hope this review offers valuable insights into this uncommon but significant complication and enhances readers’ skills in managing AVC more effectively during PCI.
6.Comparison of reference management software with new artificial intelligence-based tools
Jae Gyeong JIN ; Seung Gyu LEE ; Jea Hyeun PARK ; Jang Won HAN ; Jae Young KIM ; Jungirl SEOK ; Jeong-Ju YOO
Journal of Educational Evaluation for Health Professions 2026;23(1):2-
Reference management software (RMS) represents a cornerstone of modern academic writing and publishing. For decades, programs such as EndNote, Zotero, and Mendeley have played central roles in facilitating citation organization, bibliography formatting, and collaborative scholarship. Although each platform has introduced unique innovations, persistent limitations remain, particularly with respect to usability, accessibility, and accuracy. In parallel, the rise of generative artificial intelligence has introduced an unprecedented challenge: the inadvertent inclusion of fabricated or incorrect references mistakenly incorporated into manuscripts. This phenomenon has exposed a critical limitation of traditional RMS platforms, namely their inability to verify reference authenticity. Against this backdrop, new solutions have emerged. One such example is CiteWell (https://citewell.org/), an artificial intelligence (AI)-era RMS that introduces several notable innovations, including PubMed-integrated verification, an intuitive interface for new users, customizable journal-specific styles, and multilingual accessibility. This review provides a comprehensive historical overview of RMS, evaluates the strengths and weaknesses of major platforms, and positions emerging AI-based tools as a new paradigm that combines traditional reference management with essential safeguards for contemporary academic challenges.
7.Expert Consensus Study on the Redesign of the Sexually Transmitted Infection Surveillance System in Korea
Jin Bong CHOI ; Dong-Sook KIM ; Chae Eun SHIN ; Su-Yeon YU ; Kyu Won LEE ; Seung-Ju LEE
Journal of Korean Medical Science 2026;41(1):e18-
Background:
The management of sexually transmitted infections (STIs) at the national level is necessary for the health and well-being of individuals in society. The purpose of this study was to propose a redesign of the STI surveillance system by collecting opinions from experts.
Methods:
After the major STIs were reviewed, 1) gonorrhea, 2) chancroid, 3) Mycoplasma genitalium infection, and 4) trichomoniasis were selected as diseases requiring a redesign of the surveillance system through the Delphi method, a technique for solving problems by collecting opinions from experts. The expert panel was selected from experts on STIs (n = 17) and included members of the Korean Association of Urogenital Tract Infection and Inflammation, the Korean Society of Infectious Diseases, and the 3rd advisory committee on STIs.
Results:
The experts agreed upon the exclusion of surveillance for chancroid on the basis of the low incidence, with an agreement rate of 83%. The experts agreed upon the inclusion of M. genitalium in the surveillance system, with a high agreement rate of 88%. However, there was disagreement among the experts on whether to include trichomoniasis in the surveillance system and whether to switch to a mandatory surveillance system for gonorrhea.
Conclusion
Although a consensus was not reached in some of the surveys in this study, it involved the collection of various expert opinions. Therefore, policies should be promoted with a prioritized focus on items with high agreement, but items for which no consensus was reached need to be reviewed in greater depth through additional research and investigation.
8.Real-Time Assessment of Black Carbon Peaks Among Workers Exposed to Diesel Engine Exhaust Emissions
Ju-Hyun PARK ; Sangjun CHOI ; Kyung Ehi ZOH ; Seung Won KIM ; Dong-Hee KOH ; Won KIM ; Dong-Uk PARK
Safety and Health at Work 2026;17(1):142-150
Background:
Workers are commonly exposed to diesel engine exhaust (DEE) from diesel-powered engines and vehicles (DEVs), which contain harmful particulates such as black carbon (BC). This study aimed to characterize the peak BC exposures of workers operating or working near DEVs.
Methods:
BC levels were recorded every minute from workers driving or working near DEVs using a portable aethalometer and were categorized by job type and activity. Peak BC levels were characterized using the occupational exposure limits for DEE (measured as elemental carbon) of 10 μg/m 3 and 50 μg/ m3 as cut-off values.
Results:
Forklift operators, garbage collectors, and machine operators showed peak BC exposure levels surpassing 20 μg/m 3 , with average levels above 10 μg/m 3 . Despite their short exposure durations (<1 hour), these peaks contributed significantly (>60%) to the daily average BC exposure. The daily contribution rate of peak exposures above 10 μg/m 3 to the average daily BC exposure often exceeded 50%. The ratio of peak levels above 10 μg/m 3 and 50 μg/m 3 to the arithmetic mean was negatively correlated with exposure duration, the proportion of exposure duration, and the daily contribution of peak levels.
Conclusion
Drivers of diesel-engine vehicles often experienced significant spikes in BC exposure, highlighting the need for real-time monitoring, which is recommended as a best-practice approach to identify and mitigate short-term peak exposures.
9.Unique TTR Variants D38A and M13dup Among Korean Patients with Hereditary Transthyretin Amyloidosis:A Retrospective Single-Center Cohort Study
Min-Seung PARK ; Jae Joon LEE ; Darae KIM ; Jin-Oh CHOI ; Seok Jin KIM ; Kihyun KIM ; Ju-Hong MIN ; Hyun-Young KIM ; Hee-Jin KIM
Annals of Laboratory Medicine 2026;46(3):309-318
Background:
Transthyretin amyloidosis, a protein-misfolding disorder characterized by systemic amyloid deposition, can be classified as wild-type transthyretin amyloidosis (ATTRwt) or hereditary transthyretin amyloidosis (ATTRv), depending on the presence of transthyretin (TTR) gene variants. We examined the genetic distribution of TTR variants in Korean patients diagnosed with ATTRv.
Methods:
We retrospectively reviewed 801 participants who underwent TTR analysis at Samsung Medical Center from 2012 to 2024. The participants were categorized into two groups: in-house probands or relatives, and externally referred probands or relatives.
Results:
Pathogenic or likely pathogenic TTR variants were detected in 36 of 165 in-house probands (21.8%), among which D38A was the most frequent variant (50.0%; 18/36), followed by M13dup and E89K (8.3% each). Among referred probands, D38A was predominant (54.5%; 12/22), followed by M13dup (22.7%; 5/22). Cardiac amyloid involvement was the most common manifestation, observed in 97.2% (35/36) of in-house probands with ATTRv, followed by peripheral nervous system (PNS; 94.4%) and autonomic nervous system (ANS; 88.9%) involvement. In contrast, ANS involvement was most prevalent among in-house relatives who underwent organ evaluation (61.5%; 24/39), followed by cardiac (52.1%; 25/48) and PNS (48.7%; 19/39) involvement. Five of the eight in-house relatives harboring M13dup (62.5%) showed organ involvement, primarily in the ANS, supporting the pathogenicity of this variant.
Conclusions
This study provides the largest single-institution dataset of Korean patients with ATTRv, incorporating systematic organ assessments. The predominance of the unique TTR variants D38A and M13dup delineates a distinct genetic landscape that may facilitate accurate and timely diagnosis of ATTRv in the Korean population.
10.Detection of Fusion Genes Using RNA Sequencing in Acute Leukemia
Hyun-Young KIM ; Boram KIM ; Min-Seung PARK ; Jong-Ho PARK ; Hee Young JU ; Keon Hee YOO ; Jun Ho JANG ; Chul Won JUNG ; Hee-Jin KIM
Annals of Laboratory Medicine 2026;46(3):257-269
Background:
Fusion genes are major drivers of acute leukemia. Conventional diagnostics are limited in detecting the diverse fusions included in recently updated acute leukemia classifications. We evaluated the fusion detection performance of RNA sequencing (RNAseq) compared with that of conventional diagnostics in patients with acute leukemia.
Methods:
We retrospectively obtained the data of 101 patients with acute leukemia who underwent conventional diagnostics (i.e., karyotyping, FISH, or multiplex reverse transcription PCR) at diagnosis at Samsung Medical Center, Seoul, Korea, between September 2022 and September 2023. Whole RNA-seq was performed using the Illumina Stranded mRNA Prep kit (Illumina, San Diego, CA, USA). The concordance, sensitivity, and specificity of RNA-seq for fusion gene detection were compared with those of conventional diagnostics.
Results:
RNA-seq helped identify 52 fusion genes in 51 (50.5%) of 101 patients, with detection rates of 40.7%, 70.3%, 37.5%, and 50% in acute myeloid leukemia, B-cell acute lymphoblastic leukemia, T-cell acute lymphoblastic leukemia, and mixed-phenotype acute leukemia, respectively. RNA-seq showed 83.3% sensitivity and 80.8% concordance with conventional diagnostics; it missed eight fusions, likely because of low transcript abundance or enhancer hijacking. RNA-seq also helped clarify three previously unspecified rearrangements and detected 12 fusions (21.4%) in 56 cases that tested negative with conventional diagnostics, including four novel (KMT2A::THAP12 , RUNX1::PRPF19 , MLLT10::UBE2L6, and FUS::ZNF362) and three rare (HNRNPH1::ERG, RUNX1::USP42, and ETV6::NCOA2) fusions.
Conclusions
This was the first study to evaluate the performance of whole RNA-seq in fusion detection in patients with acute leukemia in Korea. Incorporating RNA-seq into diagnostic workflows may facilitate earlier and more precise therapeutic decisions and improve prognostic assessment in patients with acute leukemia.

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