Background/Aims: Esophageal transit scintigraphy is a non-invasive nuclear medicine imaging modality for people with esophageal transit problems. In particular, changes in esophageal motor function can be evaluated non-invasively before and after the treatment in patients undergoing peroral endoscopic myotomy (POEM) for achalasia. This study compared the changes in several parameters of esophageal transit and manometry in patients with achalasia who underwent POEM. Methods: This study retrospectively analyzed prospectively collected data from POEM participants. We included 38 patients with achalasia who underwent high-resolution manometry and esophageal transit scintigraphy before POEM and after POEM from 2016 to 2023. Results: All patients had clinical treatment successfully (Eckardt score < 3). Lower esophageal sphincter (LES) pressures were significantly reduced after POEM, including basal resting LES pressure and integrated relaxation pressure (P < 0.001).Esophageal emptying, as assessed by the residual fraction of retained radioactivity at 10 seconds after isotope ingestion, improved from 54.3% to 27.3% (P < 0.001). Analysis of the change in time-to-peak on the time-radioactivity curve showed that it shortened significantly in the upper and middle portions of the esophagus (P < 0.05) but not in the lower portion.The Eckardt symptom score significantly correlated with pre-POEM integrated relaxation pressure (P < 0.05). Post-POEM, the symptom score significantly correlated with time-to-peak of the upper portion of the esophagus (P < 0.05). Conclusions Patients with achalasia who received POEM showed improved not only manometric LES parameters but also esophageal transit. Analysis of the radiation curve’s time-to-peak showed that improved retention in the upper portion is an indicator of symptoms improvement in patients who underwent POEM.

Objective: To evaluate the performance of supplemental automated breast ultrasound (ABUS) added to mammography-based breast cancer screening for women with nondense breasts. Materials and Methods: A retrospective search of radiology databases at two tertiary institutions identified asymptomatic women with nondense breasts who underwent breast cancer screening using both digital mammography (DM) and supplemental ABUS between January 2020 and December 2023. We excluded women without sufficient follow-up data or those without an established final diagnosis, including histopathologic results. The performance measures of DM alone and ABUS combined with DM (ABUS plus DM) were compared. The primary outcome was the cancer detection rate (CDR), and the secondary outcomes were sensitivity and specificity. Subgroup analyses were performed for women with scattered fibroglandular density and almost entirely fatty breasts. Results: A total of 2,904 pairs of screening examinations were performed in 1,683 women (59 ± 10 years), detecting 26 cancers. In comparison with DM alone, ABUS plus DM showed higher CDR (9.0 vs. 7.9 per 1,000 examinations, P < 0.001), higher sensitivity (100% [26/26] vs. 88.5% [23/26], P < 0.001), and lower specificity (95.0% [2,735/2,878] vs. 97.9% [2,817/2,878], P < 0.001). In women with scattered fibroglandular density, ABUS increased the CDR from 7.4 to 8.5 per 1,000 examinations and improved the sensitivity from 87.0% [20/23] to 100% [23/23] (P < 0.001). In women with almost entirely fatty breasts, ABUS plus DM showed the same CDR (16.4 per 1,000 examinations) and sensitivity (100% [3/3]) as DM alone. Three cancers (11.5% [3/26]), all of which were stage T1N0, were detected only by supplemental ABUS. Conclusion Supplemental ABUS improved cancer detection and sensitivity in women with nondense breasts, with the benefits primarily observed in those with scattered fibroglandular density.

Purpose: Neoadjuvant chemotherapy (NAC) significantly revolutionized the management of locally advanced breast cancer, especially in human epidermal growth factor receptor 2 (HER2)-positive and triple-negative subtypes. However, its effectiveness is limited in estrogen receptor (ER)-positive, HER2-negative breast cancer. This study investigates the clinical response and prognosis of ER-positive, HER2-negative breast cancer after NAC. Methods: The clinicopathological characteristics and treatment responses of 149 patients with ER-positive, HER2-negative breast cancer treated with NAC and surgery at The Catholic University of Korea, Seoul St. Mary’s Hospital between 2018 and 2023 were retrospectively analyzed. Pathologic complete response (pCR) was defined as the absence of invasive tumors (ypT0/is, ypN0). Disease-free survival (DFS) and overall survival (OS) were analyzed using Kaplan-Meier methods, stratified by age (≤50 years vs. >50 years). Results: Among 149 patients, 13 (8.7%) achieved pCR, 87 (58.4%) attained partial responses, 40 (26.8%) had stable disease, and 9 (6.0%) experienced progressive disease. RECIST responses differed significantly by age (P = 0.003). DFS (P = 0.011) and OS (P = 0.005) were significantly associated with clinical response in patients aged ≤50 years. Post-NAC Ki-67 was associated with DFS (P = 0.013) but not OS (P = 0.083) in patients aged ≤50 years. Clinical responses and post-NAC Ki-67 were not associated with DFS (P = 0.544) or OS (P = 0.569) in patients aged >50 years. Conclusion In ER-positive, HER2-negative breast cancer, clinical responses and post-NAC Ki-67 were significant prognostic factors in patients aged ≤50 years but not in older patients. These findings highlight the need for tailored therapeutic approaches that consider age-specific prognostic differences.

Background and Objectives: Primary prevention (PP) implantable cardioverter-defibrillator (ICD) therapy for ischemic cardiomyopathy (ICM) is underused in Asian countries, including South Korea. Both clinical and hospital factors may influence appropriate ICD use. We evaluated whether determinants of PP ICD implantation differ by hospital implantation volume. Methods: In this prospective, multicenter observational registry (blinded for review), patients eligible for PP ICD were enrolled. Factors associated with ICD implantation—clinical characteristics and hospital-level systems—were examined across 4 large-volume hospitals (≥ 15 implants during the study) and 12 small-volume hospitals (< 15). Multivariable logistic regression identified independent predictors. Results: Among 3,083 ICM patients (2,403 men; median age 70 years), PP ICD implantation rates were 10.8% in large-volume and 5.7% in small-volume hospitals. Across groups, male sex and chronic kidney disease independently predicted ICD implantation. Regarding hospital factors, non-monetary incentives for referral were the sole independent predictor in large-volume centers (odds ratio [OR], 3.55; 95% confidence interval [CI], 2.07–6.10;P < 0.001). In small-volume centers, heart failure conferences (OR, 12.73; 95% CI, 1.72–94.37;P = 0.013), structured education systems (OR, 11.72; 95% CI, 2.45–56.12; P = 0.02), and pacemaker clinics (OR, 11.4; 95% CI, 2.24–58.39; P = 0.003) were independently associated with implantation. Conclusions Clinical predictors of PP ICD use were consistent across hospital volumes, but hospital-level determinants differed. Referral incentives characterized large-volume centers, whereas conferences, education systems, and pacemaker clinics were key in smallvolume centers. Tailored institutional strategies by hospital volume may help close the PP ICD underuse gap and improve evidence-based implementation.

Objective: This study aimed to investigate the prevalence and characteristics of impacted teeth (ITs) in orthodontic patients at university dental hospitals in Korea. Methods: This study included 14,774 patients who visited the Department of Orthodontics at 10 university dental hospitals in Korea between 2020 and 2022 and underwent orthodontic diagnosis. The prevalence and characteristics of ITs were investigated using orthodontic diagnostic records, radiographs, and diagnostic casts. Results: The prevalence of ITs, excluding third molar impaction, in Korean orthodontic patients was 13.6% (n = 2,014).The prevalence of ITs in pediatric orthodontic patients was 24.5% (n = 1,614).Of these patients, 68.2% had one IT, 27.5% had two ITs, 24.3% had bilateral IT, and 75.7% had unilateral IT. The most frequent IT was the maxillary canine (50.1%), followed by the mandibular second molar (11.7%), and maxillary second premolar (9.6%). An abnormal eruption path (46.5%) was the most frequent etiology. Orthodontic traction after surgical exposure (70.6%) was the most frequent treatment option. Among the patients with ITs, 29.8% had other dental anomalies, such as tooth agenesis (8.7%), microdontia (8.0%), and supernumerary teeth (5.1%). Furthermore, 50.8% had complications such as cystic lesions (18.3%), transposition (17.7%), and root resorption (14.8%).Among the patients with maxillary canine impaction, 62.2% had labial maxillary canine impaction and 21.1% had palatal maxillary canine impaction. Conclusions The prevalence of ITs in Korean orthodontic patients at university dental hospitals was high, particularly in pediatric orthodontic patients.

Objective: This study aimed to investigate the prevalence and characteristics of impacted teeth (ITs) in orthodontic patients at university dental hospitals in Korea. Methods: This study included 14,774 patients who visited the Department of Orthodontics at 10 university dental hospitals in Korea between 2020 and 2022 and underwent orthodontic diagnosis. The prevalence and characteristics of ITs were investigated using orthodontic diagnostic records, radiographs, and diagnostic casts. Results: The prevalence of ITs, excluding third molar impaction, in Korean orthodontic patients was 13.6% (n = 2,014).The prevalence of ITs in pediatric orthodontic patients was 24.5% (n = 1,614).Of these patients, 68.2% had one IT, 27.5% had two ITs, 24.3% had bilateral IT, and 75.7% had unilateral IT. The most frequent IT was the maxillary canine (50.1%), followed by the mandibular second molar (11.7%), and maxillary second premolar (9.6%). An abnormal eruption path (46.5%) was the most frequent etiology. Orthodontic traction after surgical exposure (70.6%) was the most frequent treatment option. Among the patients with ITs, 29.8% had other dental anomalies, such as tooth agenesis (8.7%), microdontia (8.0%), and supernumerary teeth (5.1%). Furthermore, 50.8% had complications such as cystic lesions (18.3%), transposition (17.7%), and root resorption (14.8%).Among the patients with maxillary canine impaction, 62.2% had labial maxillary canine impaction and 21.1% had palatal maxillary canine impaction. Conclusions The prevalence of ITs in Korean orthodontic patients at university dental hospitals was high, particularly in pediatric orthodontic patients.

Purpose: We assessed human papillomavirus (HPV) genotype-based risk stratification and the efficacy of cytology testing for cervical cancer screening in patients with atypical squamous cells of undetermined significance (ASCUS)/low-grade squamous intraepithelial lesion (LSIL). Materials and Methods: Between 2010 and 2021, we monitored 1,273 HPV-positive women with ASCUS/LSIL every 6 months for up to 60 months. HPV infections were categorized as persistent (HPV positivity consistently observed post-enrollment), negative (HPV negativity consistently observed post-enrollment), or non-persistent (neither consistently positive nor negative). HPV genotypes were grouped into high-risk (Hr) groups 1 (types 16, 18, 31, 33, 45, 52, and 58) and 2 (types 35, 39, 51, 56, 59, 66, and 68) and a low-risk group. Hr1 was subdivided into types (a) 16 and 18; (b) 31, 33, and 45; and (c) 52 and 58. Cox regression and machine learning (ML) algorithms were used to analyze progression rates. Results: Among 1,273 participants, 17.6% with persistent HPV infections experienced disease progression versus no progression in the HPV-negative group (p < 0.001). Cox analysis revealed the highest hazard ratios (HRs) for Hr1-a (11.6, p < 0.001), followed by Hr1-b (9.26, p < 0.001) and Hr1-c (7.21, p < 0.001). HRs peaked at 12-24 months, with Hr1-a maintaining significance at 24-36 months (10.7, p=0.034). ML analysis identified the final cytology change pattern as the most significant factor, with 14-15 months the optimal time for detecting progression from the first examination. Conclusion In ASCUS/LSIL cases, follow-up strategies should be based on HPV risk types. Annual follow-up was the most effective monitoring for detecting progression/regression.

Background: Shortage of organ donors in the Republic of Korea has become a major problem. To address this, it has been questioned whether heart transplant (HTx) allocation should be modified to reduce priority of older patients. We aimed to evaluate post-HTx outcomes according to recipient age and specific pre-HTx conditions using a nationwide prospective cohort. Methods: We analyzed clinical characteristics of 628 patients from the Korean Organ Transplant Registry who received HTx from January 2015 to December 2020. Enrolled recipients were divided into three groups according to age. We also included comorbidities including ambulatory status. Non-ambulatory status was defined as pre-HTx support with either extracorporeal membrane oxygenation, continuous renal replacement therapy, or mechanical ventilation. Results: Of the 628 patients, 195 were < 50 years, 322 were 50–64 years and 111 were ≥ 65years at transplant. Four hundred nine (65.1%) were ambulatory and 219 (34.9%) were nonambulatory. Older recipients tended to have more comorbidities, ischemic cardiomyopathy, and received older donors. Post-HTx survival was significantly lower in older recipients (P = 0.025) and recipients with non-ambulatory status (P < 0.001). However, in contrast to non-ambulatory recipients who showed significant survival differences according to the recipient’s age (P = 0.004), ambulatory recipients showed comparable outcomes (P = 0.465). Conclusion Our results do not support use of age alone as an allocation criterion. Transplant candidate age in combination with some comorbidities such as non-ambulatory status may identify patients at a sufficiently elevated risk at which suitability of HTx should be reconsidered.

Purpose: Obesity refers to a condition in which there is excessive fat in the body and is caused by an imbalanced diet and a decrease in physical activity. Accordingly, regular exercise is reported to help improve and prevent obesity. Therefore, this study investigated the effects of short-term resistance training (RT) on weight loss, lipid profiles, blood pressure, atherogenic indices, and inflammation in middle-aged mice. Methods: Adult mice (7.5-month-old) were randomly divided into three groups comprising 7 mice per group: a normal diet group (NDC); a high-fat diet group (HDC, 45% total calories as fat); and a high-fat diet plus resistance training group (HDRT). The mice in the resistance training group performed climbing exercises using a ladder for the experimental period of 5 days/week for 4 weeks. The indicated intensity load was adjusted by individual % of animal body weight. The load gradually increased every week, and a total of 4 repetitions/set and 3 sets/day with 1 minute of rest provided between sets were performed. After sacrifice, analysis of serum and mRNA expression in the tissues were performed. Results: The HDC group showed a significant increase in systolic blood pressure (SBP) compared to the NDC group, while the HDRT group had a lower SBP relative to the HDC group. RT significantly improved blood lipid levels (triglycerides [TG], low-density lipoprotein [LDL], non-high-density lipoprotein [nonHDL], and very-low-density lipoprotein cholesterol [VLDL-C]). Arteriosclerosis improved through resistance training as observed in the changes in the arteriosclerosis indices (atherogenic index of plasma [AIP], Castelli risk index [CRI]-I, CRI-II, and atherogenic coefficient [AC]). In addition, the HDRT group showed decreased mRNA expression levels of tumor necrosis factor-alpha (Tnfa), interleukin-1 beta (Il-1b), and Il-6 in muscle tissue when compared with the HDC. Conclusion This study confirmed that RT improves blood lipids and inflammation profiles, regulates blood pressure, and improves atherosclerosis in obese mice.

Background and Objectives: Several real-world studies have been done in patients with nonvalvular atrial fibrillation (NVAF); however, information on its safety profile in patients with renal impairment is limited. XARENAL, a real-world study, aimed to prospectively investigate the safety profile of rivaroxaban in patients with NVAF with renal impairment (creatinine clearance [CrCl], 15–49 mL/min). Methods: XARENAL is an observational single-arm cohort study in renal impairment NVAF patients. Patients were followed up approximately every 3 months for 1 year or until 30 days following early discontinuation. The primary endpoint was major bleeding events. All adverse events, symptomatic thromboembolic events, treatment duration, and renal function change from baseline were the secondary endpoints. Results: XARENAL included 888 patients from 29 study sites. Overall, 713 (80.3%) had moderate renal impairment (CrCl, 30–49 mL/min), and 175 (19.7%) had severe renal impairment (CrCl, 15–29 mL/min) with a mean estimated glomerular filtration rate (eGFR) of 45.2±13.0 mL/min/1.73 m 2 . The mean risk scores were 3.3±1.4 and 1.7±0.9 for CHA 2 DS 2 -VASc score and HAS-BLED score, respectively. An incidence proportion of 5.6% (6.2 events per 100 patient-years) developed major bleeding; however, fatal bleeding occurred in 0.5% (0.5 events per 100 patient-years). The mean change in the eGFR was 2.22±26.47 mL/min/1.73 m 2 per year. Conclusions XARENAL observed no meaningful differences in major bleeding events from other previous findings as well as renal function changes in rivaroxaban-treated NVAF patients with renal impairment, which is considered to be acceptable in clinical practice.