Endoscopic surgery has emerged as a viable treatment option for cervical stenotic myelopathy, offering several advantages over conventional approaches. In multilevel cervical myelopathy, traditional microscopic laminoplasty via the posterior approach requires muscle dissection along the spinous process, which serves as the insertion point for stabilizing muscles, thereby disrupting the posterior tension band. Recently, endoscopic laminoplasty techniques have been explored; however, these often involve detaching the spinous tip from the lamina, compromising the cervical fulcrum. In this report, we introduce a novel surgical technique using a unilateral biportal endoscopy (UBE) system that preserves key cervical structures typically damaged by prior open or endoscopic laminoplasty methods. An 82-year-old man presented with bilateral lower-extremity weakness. Imaging revealed stenosis at C3–4–5 with associated cord signal changes. Maintain anatomy laminoplasty was performed using the UBE system, preserving both the posterior tension band and the spinous process fulcrum. Postoperatively, the modified Japanese Orthopaedic Association and Numeric Rating Scale scores improved. The patient was discharged on postoperative day 4. This new unilateral biportal endoscopic cervical laminoplasty is a safe, effective, and minimally invasive technique that achieves complete decompression in multilevel cervical stenotic myelopathy while maintaining critical anatomical structures.

Although venous invasion (VI) is associated with distant metastasis and observed in >50% of pT2–4 colorectal cancers (CRCs), the role of VI in pT1 CRCs is not well-defined. Methods: Thirty-four surgically resected pT1 CRCs were reevaluated for 2-dimensional (2D) VI using hematoxylin and eosin (H&E)–stained slides with additional elastic and desmin immunohistochemical staining (cohort A). Additionally, 27 pT1 CRCs without knowing VI status were selected for 3-dimensional (3D) VI evaluation only (cohort B). All 61 cases (cohorts A and B) were studied in 3D using tissue clearing. Results: VI was detected more commonly in 3D (17/34, 50.0%) than in 2D H&E slide evaluation (9/34, 26.5%, p = .047). When VI was identified in 3D (27/61, 44.3%), the most common phase was that of intraluminal growth (22/27, 81.5%), followed by intravasation (7/27, 25.9%) and extravasation (5/27, 18.5%). E-cadherin expression was characterized in 3D in foci of VI and varied in each phase of invasion. Conclusions: All three phases were observed in VI of pT1 CRCs. The extravasation of neoplastic cells from foci of VI in pT1 CRC suggests that VI could be a route of intratumoral spreading in a subset of pT1 CRCs.

The Pheochromocytoma of the Adrenal Gland Scaled Score (PASS) is widely used for risk stratification in pheochromocytoma and paraganglioma (PPGL), but its clinical utility is limited by inter-observer variability of its parameters and inconsistent predictive performance. Methods: We conducted a multicenter retrospective study of 1,518 patients with PPGL from five tertiary referral centers in Korea. Prognostic utility of PASS system was assessed using logistic regression, Kaplan-Meier analysis, and receiver operating characteristic (ROC) curve analysis. Inter-observer variability was inferred by comparing area under the ROC curve (AUCs) across institutions. Simplified PASS systems were developed based on multivariable analysis of key histopathological parameters. Results: The PASS system was a significant predictor of adverse events and recurrence-free survival. Although the PASS system demonstrated only modest discriminative ability (AUC, 0.673), it showed a high negative predictive value (NPV, 0.885), supporting its usefulness as a screening tool for benign behavior. However, there was significant inter-institutional variability in PASS performance (AUC; range, 0.513 to 0.727; p < .05). The 3-factor Simple PASS, which incorporates necrosis, spindling, and mitotic figures, exhibited less inter-observer variation. The 4-factor Simple PASS, which adds vascular invasion to the 3-factor model, also showed reduced inter-observer variability and improved AUC and NPV compared to the original PASS system. Conclusions: In this multicenter cohort, the PASS system demonstrated high NPV and screening potential, but significant inter-observer variability remains a challenge. Simplification of the PASS system and enhanced pathologist training may improve reproducibility and clinical utility in PPGL risk stratification.

Genetic variation in the leptin receptor (LEPR) gene has been implicated in metabolic regulation, while the gut microbiome and circulating metabolites are increasingly recognized as mediators of host metabolic phenotype. However, the systems-level interactions among LEPR genotypes, gut microbial composition, and serum metabolomic profiles remain poorly understood, particularly in healthy individuals. We conducted a cross-sectional study involving 37 healthy Korean adults. Three LEPR single nucleotide polymorphisms (rs1137101, rs1173100, rs790419) were genotyped. Untargeted metabolomics of fasting serum was performed using gas chromatography–time-of-flight mass spectrometry, and gut microbiome composition was profiled by 16S rRNA gene sequencing. Statistical analysis included principal component analysis, Mann–Whitney U tests, and Spearman correlations. Network analysis integrating microbiome, metabolomic, and clinical phenotype data was conducted using Cytoscape. A total of 54 serum metabolites were identified. LEPR genotypes, particularly rs1137101 and rs1173100, were associated with differences in metabolites such as pimelic acid, malonic acid, and 2,4-dihydroxybutyric acid. Firmicutes negatively correlated with saturated fatty acids and organic acids, whereas Actinobacteria positively correlated with cholesterol and amino acids. Network analysis revealed indole-3-acetate and cholesterol as central nodes linking microbial taxa with body mass index and leptin levels. However, no direct molecular pathways connecting leptin or its receptor were identified. LEPR genetic variation is associated with distinct serum metabolomic patterns and microbiome–host networks in healthy adults. Although no direct leptin signaling links were found, network-level associations suggest indirect genetic influences on metabolic states through microbiome–metabolome interactions.These findings advance understanding of personalized metabolic regulation and gene–microbiome interplay.

Objectives: . Obstructive sleep apnea (OSA) is a common sleep-related breathing disorder that is strongly influenced by obesity, the most important modifiable risk factor. Effective weight management is therefore essential for optimal OSA care. This guideline provides updated, evidence-based recommendations for the evaluation and management of obesity in adults with OSA, incorporating recent advances in lifestyle, pharmacologic, and surgical interventions. Methods: . The Korean Society of Sleep and Breathing convened a multidisciplinary panel. A systematic literature search was performed across major databases through 2025. Evidence was appraised using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, and recommendations were formulated by consensus using the Evidence-to-Decision framework. Results: . Eight statements were developed. Key recommendations include recognizing obesity as a major risk factor; routinely assessing overweight and obesity; and implementing structured weight reduction through diet, exercise, and behavioral therapy. Glucagon-like peptide-1 receptor agonists are recommended when lifestyle interventions are insufficient, and bariatric/metabolic surgery is advised for severe obesity unresponsive to nonsurgical treatment. Weight loss improves the apnea-hypopnea index, symptoms, and cardiometabolic markers and may reduce positive airway pressure needs. Continued follow-up is recommended even after clinical improvement. Conclusion . Weight management is a core component of OSA treatment. This guideline offers practical, evidence-based strategies to support clinicians in delivering effective, obesity-focused care for adults with OSA.

Objective: : To identify sex-specific risk factors for postoperative urinary retention (POUR) in patients undergoing spine surgery with total intravenous anesthesia (TIVA) and explore differences between male and female patients. Methods: : A retrospective chart review was conducted on 446 adult patients (268 males, 178 females) who underwent spine surgery with TIVA from January 1, 2019 to December 31, 2023. Propensity score matching was applied to adjust for confounding variables, resulting in 328 matched patients (164 males and 164 females). Multivariable logistic regression analyses were performed to identify independent risk factors for POUR. Residual urine volume ≥300 mL was used to define POUR. Results: : Male patients had a higher incidence of POUR compared to female patients. Significant risk factors for POUR in males included myelopathy (adjusted odds ratio [aOR], 5.17; 95% confidence interval [CI], 1.11–24.15), benign prostatic hyperplasia (BPH) (aOR, 2.63; 95% CI, 1.02–6.78), and prolonged anesthesia time ≥240 minutes (aOR, 2.54; 95% CI, 1.13–5.72). No significant risk factors were found in female patients. Myelopathy and prolonged anesthesia were associated with an increased risk of POUR across the overall population. Conclusion : Male sex, myelopathy, BPH, and prolonged anesthesia time are significant risk factors for POUR following spine surgery with TIVA. Given these findings, particular attention should be paid to myelopathy, a history of BPH, and anesthesia time in male patients.

Subarachnoid hemorrhage (SAH) is a stroke subtype with high mortality and poor functional outcomes. Prompt occlusion of a ruptured aneurysm at an early stage is crucial to prevent rebleeding, which can result in even higher mortality and more severe disabilities. The most critical initial decision in SAH management is the choice of treatment method with surgical clipping or endovascular coiling. We aimed to develop an evidence-based clinical guideline to select the optimal initial treatment in patients with SAH. We developed this guideline based on evidence from systematic reviews and meta-analyses via a de novo process. A systematic literature review was conducted across four databases (MEDLINE, Embase, Cochrane, and KoreaMed) to answer two population, intervention, comparison, outcome questions comparing clipping and coiling. The risk of bias was assessed using ROB 2.0 and the Newcastle-Ottawa Scale. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagrams and meta-analyses were generated for functional outcome and mortality. We included six randomized control trials (RCTs) and 58 observational studies. Meta-analysis of RCTs showed that coiling improved functional outcomes compared to clipping (odds ratio [OR], 0.91; 95% confidence interval [CI], 0.86–0.97). No significant mortality difference was observed in RCTs (OR, 1.38; 95% CI, 0.91–2.09), but non-RCTs favored clipping for reduced mortality (OR, 0.77; 95% CI, 0.69–0.86). However, it is difficult to generalize these findings to all clinical situations, as patients with SAH have a highly variable clinical course. Final treatment decision should be tailored to the individual patient’s status, including aneurysm location, morphology, and the expertise available at the treatment center. Such decisions are best made by specialists such as a board-certified physician and should be explained to the patient and their caregivers, along with the rationale for selecting the most appropriate treatment at the given hospital. Korea has many certified endovascular neurosurgeons, cerebrovascular surgeons, and certified cerebrovascular centers. Proper selection of the most suitable treatment method by certified physicians and centers would greatly benefit patient outcomes and healthcare professionals.

Accurate and early identification of stroke and large vessel occlusion (LVO) in emergency settings is essential for improving patient outcomes and ensuring the efficient allocation of medical resources. This clinical practice guideline systematically reviews domestic and international literature and conducts meta-analyses to evaluate the utility and diagnostic accuracy of stroke assessment tools used in prehospital emergency medical services (EMS). We developed a guideline based on evidence from systematic reviews and meta-analyses via a de novo process. A systematic literature review was conducted to evaluate the usefulness of diagnostic EMS assessment tools for diagnosing stroke and LVO. Overall, 70 non-randomized control studies were selected for this study. A meta-analysis was conducted with a subgroup analysis to distinguish between patients with stroke and those with LVO. EMS tools demonstrated high sensitivity but low specificity for diagnosing stroke. In the prehospital setting, using validated EMS stroke assessment tools is recommended for the early identification of stroke and LVO. Upon hospital arrival, stroke specialists should conduct further evaluation and triage to confirm the diagnosis and guide appropriate management. Delays in diagnosing LVO are frequently unacceptable. While experts advocate for the use of EMS assessment tools to facilitate early identification of LVO, these tools alone lack adequate sensitivity. Therefore, further diagnostic evaluations and consultation with stroke specialists upon hospital arrival are recommended.