Background/Aims: Endoscopic anti-reflux therapy is a therapeutic option for gastroesophageal reflux disease (GERD), providing durable effects. However, clinical data from Korea remain limited. This study evaluates the clinical outcomes of endoscopic radiofrequency Stretta therapy in Korean patients. Methods: A retrospective analysis was conducted on 71 patients with GERD who underwent Stretta therapy at 2 tertiary hospitals in Korea between November 2015 and July 2021. Clinical outcomes, including patient satisfaction, medication cessation or reduction, and complications, were evaluated. Pre- and post-procedural esophageal manometry and 24-hour pH monitoring test results were also analyzed. Results: Patient satisfaction rates at 1, 6, and 12 months post-procedure were 54.7% (35/64), 70.0% (28/40), and 75.0% (21/28), respectively. Medication cessation or reduction was achieved in 31.2% (20/64) at 1 month, 70.0% (28/40) at 6 months, and 67.9% (19/28) at 12 months. Esophageal manometry (n = 21) showed no significant changes in mean lower esophageal sphincter pressure (18.7 mmHg [2.5-52.9] vs 17.4 mmHg [0.0-43.0], P = 0.702) or mean integrated relaxation pressure (8.2 mmHg [0.0-28.0] vs 10.1 mmHg [0.0-31.0], P = 0.840). The 24-hour pH monitoring (n = 18) demonstrated a nonsignificant decrease in acid exposure time (pH < 4) from 2.3% (0.0-8.4) to 1.6% (0.0-7.3) (P = 0.182). Similarly, the DeMeester score decreased non-significantly from 8.4 (0.8-27.7) to 6.6 (0.8-21.8) (P = 0.352). No procedure-related complications occurred. Conclusion Endoscopic radiofrequency Stretta therapy appears to be a safe treatment option for GERD and may provide favorable patient satisfaction and medication reduction.

Background/Aims: Nocturnal acid reflux disrupts sleep and impairs quality of life. Proton pump inhibitors provide insufficient suppression of nocturnal acid secretion, whereas fexuprazan offers prolonged acid suppression. We compared the efficacy of fexuprazan and esomeprazole in controlling nocturnal reflux. Methods: In a randomized and crossover study, patients received fexuprazan or esomeprazole daily for 4 weeks, followed by a washout and crossover to the alternate medication for another 4 weeks, with a final washout completing the sequence. Severity (scores 0-10), frequency, sleep disturbance, and medication preferences were evaluated. Results: Thirty-nine patients were enrolled and randomized to receive either fexuprazan (n = 20) or esomeprazole (n = 19) first. After the first treatment, fexuprazan reduced severity from 7.5 ± 1.7 to 1.4 ± 1.7 (81.3% decrease), versus 7.8 ± 1.5 to 2.8 ± 1.9 (64.1% decrease) with esomeprazole (P = 0.012). In patients with severe symptoms (scores ≥ 7), fexuprazan led to significantly greater improvement than esomeprazole (P = 0.008). Following the first washout, the second crossover treatment resulted in greater improvement in symptom severity with fexuprazan (P = 0.001). During the second washout, nocturnal symptoms severity and frequencies were better controlled with fexuprazan than with esomeprazole (P = 0.005 and 0.019). Patients who switched from esomeprazole to fexuprazan preferred fexuprazan (P = 0.018). Conclusions Fexuprazan was more effective than esomeprazole in controlling nocturnal reflux symptom, particularly in patients with severe symptoms. Fexuprazan may offer a therapeutic advantage for patients with severe and persistent nocturnal reflux despite proton pump inhibitor therapy.

Purpose: The aim of this study is to compare the detection ability of quality of life (QoL) changes and responsiveness of the KOrean QUality of life in Stomach cancer patients Study group (KOQUSS)-40 and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ). Materials and Methods: A multicenter prospective observational study was conducted to evaluate QoL changes after various gastrectomies between January 2021 and April 2022. Participants were instructed to complete the KOQUSS-40 and EORTC QLQ-C30/STO22 preoperatively and at 1, 3, 6, and 12 months postoperatively. QoL changes over time and QoL responsiveness were assessed for each questionnaire. Results: Data from 491 patients who underwent curative gastrectomy for gastric cancer at 22 institutions were analyzed. The summary scores of the KOQUSS-40 and EORTC QLQ-STO22 showed significant differences between the total and proximal gastrectomy groups (p=0.044 and p=0.038, respectively), but no difference was observed for the EORTC QLQ-C30. Dysphagia on the KOQUSS-40 was significantly different between the total and proximal gastrectomy groups (p=0.031); however, dysphagia on the EORTC QLQ-STO22 did not differ. The responsiveness of the KOQUSS-40 was similar to that of the EORTC QLQ in patients who experienced ≥ 10% body weight loss, but approximately 10% less in patients receiving adjuvant chemotherapy than the EORTC QLQ. Conclusion KOQUSS-40 has several advantages over EORTC QLQ-C30/STO22 when comparing QoL between the total and proximal gastrectomy groups. The findings provide information for researchers investigating the QoL of patients who have undergone curative gastrectomy for gastric cancer.

Purpose: The male predominance in the incidence of gastric cancer (GC) is established; however, sex differences in the prognosis of GC remain controversial. As such, this study analyzed the prognosis of patients with GC based on age and sex. Materials and Methods: Data from 14,739 patients diagnosed with GC at Seoul National University Bundang Hospital between 2003 and 2023 were analyzed. Baseline characteristics, histological types of GC, overall and GC-specific survival rates (age and stage stratification), and associated risk factors were analyzed. Results: Females were significantly younger (p < 0.001) and exhibited more gastric body cancers (p < 0.001) and tumors with diffuse-type or poorly differentiated histology (p < 0.001) than males. Females exhibited an advantage over males in terms of overall survival (p=0.004), but not in GC-specific survival. However, age stratification revealed significant sex differences, that females < 50 years of age exhibited survival disadvantages (p < 0.001); however, this trend was reversed with age, and females > 60 years exhibited survival advantages (p < 0.001) for both overall and GC-specific survival. This may be explained by the lower ratio of diffuse-type GC as females age. Furthermore, in the analysis according to stage, females with stage IV disease exhibited significant survival disadvantages, with significantly younger age and a higher proportion of diffuse-type GC which exhibits aggressive features, resulting in poorer survival than in males. Conclusion Age and stage stratification revealed significant differences in survival between the sexes, which can be helpful for public health strategies.

Spinal melanocytoma (SMC) is a rare, slow-growing tumor arising from melanocytes in the spinal cord. We report a patient with a cervical intra- and extradural spinal tumor causing progressive weakness and numbness. On magnetic resonance imaging (MRI), the lesion showed intense homogeneous enhancement, similar to that seen in common neurogenic spinal tumors. After complete resection, pathological examination confirmed melanocytoma. A review of previously reported cases identified 26 reports of this tumor in the cervical spine, most of which were treated with complete surgical resection. Gross total resection is the preferred treatment, although radiation therapy may be considered when residual tumor remains. We report a 25-year-old male patient who presented with progressive weakness and numbness in both the upper and lower extremities for 3 months. MRI showed homogeneous enhancement. The mass compressed the spinal cord at C6–7 and extended through the neural foramen. Based on the MRI findings, spinal schwannoma was suspected preoperatively. Surgical resection was performed with laminectomy, durotomy, and right facetectomy. A dark-colored mass with well-demarcated margins was exposed and removed. Postoperative MRI confirmed complete removal of the mass. The patient recovered well, and his preoperative myelopathic symptoms gradually improved. SMC is a rare benign tumor that may be mistaken for schwannoma. The treatment of choice is gross total resection.

Purpose: To compare the anatomical and clinical outcomes based on the distance from the corneal limbus to the scleral tunnel in flanged intrascleral intraocular lens (IOL) fixation. Methods: We retrospectively analyzed the medical records of patients who underwent scleral fixation of flanged IOLs. Group 1 (54 eyes) had a distance of 2.1 mm from the corneal limbus to the scleral tunnel, and Group 2 (48 eyes) had a distance of 2.8 mm. We evaluated the best corrected visual acuity (BCVA), postoperative complications, IOL tilt and decentration, refractive prediction error (RPE), effective lens position, and iris-IOL distance. Results: The BCVA, postoperative complications, IOL tilt, and IOL decentration did not differ between the two groups (p > 0.05). The RPE showed a hyperopic shift in Group 1 and a myopic shift in Group 2 (Group 1: +0.24 ± 0.68 D, Group 2: -0.03 ± 0.43 D, p = 0.03). The iris-IOL distance was statistically longer in Group 1 compared to Group 2 (Group 1: 1.02 ± 0.40 mm, Group 2: 0.57 ± 0.32 mm, p = 0.02). The incidence of pupillary optic capture was significantly higher in Group 2 compared to Group 1 (Group 1; 0%, Group 2; 8.3%, p = 0.03). Conclusions It should be considered that a shorter distance from the corneal limbus to the scleral tunnel results in a postoperative hyperopic shift and reduces the incidence of pupillary optic capture when performing flanged intrascleral IOLs fixation.

Arterial pH reflects both metabolic and respiratory distress in cardiac arrest and has prognostic implications. However, it was excluded from the 2024 update of the Utstein out-of-hospital cardiac arrest (OHCA) registry template. We investigated the rationale for including arterial pH into models predicting clinical outcomes. Methods: Data were sourced from the Korean Cardiac Arrest Research Consortium, a nationwide OHCA registry (NCT03222999). Prediction models were constructed using logistic regression, random forest, and eXtreme Gradient Boosting frameworks. Each framework included three model types: pH, low-flow time, and combined models. Then the area under the receiver operating characteristic curve (AUROC) of each predicting model was compared. The primary outcome was 30- day death or neurologically unfavorable status (cerebral performance category ≥3). Results: Among the 15,765 patients analyzed, 92.2% experienced death or unfavorable neurological outcomes. The predicting performance of the models including pH (AUROC, 0.92–0.94) were comparable to the models including low-flow time in all frameworks (0.93–0.94) (all P>0.05). Inclusion of pH into low-flow time models consistently showed higher AUROCs than individual models in all frameworks (AUROC, 0.93–0.95; all P<0.05). Conclusions: The predicting performance of models including arterial pH was comparable to models including low-flow time, and addition of arterial pH into low-flow time models could increase the performance of the models. Key Words: blood pH; hydrogen-ion con

Vancomycin, a vital antibiotic for treating gram-positive bacterial infections, requires therapeutic drug monitoring (TDM) because of its substantial pharmacokinetic variability. While traditional TDM relies on steady-state trough concentrations, recent guidelines advocate the area under the concentration–time curve (AUC) as the target index. However, detailed protocols for AUC estimation are lacking, leading to potential discrepancies among institutions. We surveyed medical institutions in Korea regarding vancomycin TDM, including AUC estimation. Nineteen participants responded to the TDM case challenge under three patient scenarios. For an ordinary patient in Case 1, the overall CV for AUC values was 0.4% when both trough and peak concentrations were included in the AUC calculation and 1.9% when utilizing only the trough concentration. For Case 2, an older patient with obesity, the corresponding CV was 6.6%. For Case 3 with multiple trough concentrations, the CV was 15.6%, reflecting variations in the selective use of data. Although the agreements in Case 1 were good, significant variability in AUC estimation was noted in cases involving atypical patient characteristics or old TDM data. Our study provides insight into the current status of vancomycin TDM in Korea and underscores the need for standardized operational protocols for AUC estimation.

Background: Ensuring reference material (RM) commutability is crucial for evaluating measurement traceability in order to standardize laboratory tests. However, commutability assessment is not routinely performed. We assessed whether RMs prepared following CLSI C37-A guidelines could be used without assessing commutability by evaluating their commutability for four lipid measurements using the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) and CLSI EP14 protocols. Methods: We analyzed total cholesterol (TC), triglycerides (TGs), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) in frozen sera from 20 individuals and 11 RMs, prepared by the Korea Disease Control and Prevention AgencyLaboratory Standardization Project (per CLSI C37-A), using six routine measurement procedures (MPs). Regression equations and 95% prediction intervals derived from single-donor sera were analyzed following CLSI EP14. The IFCC protocol was used to assess differences in inter-MP biases between RM and clinical samples. The effect of the TG concentration on commutability was evaluated by analyzing biases between MP results and reference procedure-assigned values. Results: RMs were commutable for most MP pairs for TC and TG. Commutability for HDL-C and LDL-C varied across RMs, with RM10 and RM11 showing higher TG levels (2.38 and 2.95 mmol/L, respectively) and lower commutability. Increased bias percentages from assigned values were observed for RMs with higher TG levels. Conclusions RMs prepared per CLSI C37-A were commutable with most MP pairs for TC and TG. Elevated TG levels affected HDL-C and LDL-C commutability, highlighting the need to consider TG concentrations during RM preparation and assess commutability to standardize laboratory tests.